LuaSettings: Add a method to initialize a setting properly (#7371)

* LuaSettings/DocSettings: Updated readSetting API to allow proper initialization to default.
Use it to initialize tables, e.g., fixing corner-cases in readerFooter that could prevent settings from being saved.
(Fixes an issue reported on Gitter).
* LuaSettings/DocSettings: Add simpler API than the the flip* ones to toggle boolean settings.
* Update LuaSettings/DocSettigns usage throughout the codebase to use the dedicated boolean methods wher appropriate, and clean up some of the more mind-bending uses.
* FileChooser: Implement an extended default exclusion list (fix #2360)
* ScreenSaver: Refactor to avoid the pile of kludges this was threatening to become. Code should be easier to follow and use, and fallbacks now behave as expected (fix #4418).

frontend/apps/cloudstorage/cloudstorage.lua

@@ -32,6 +32,7 @@ local CloudStorage = Menu:extend{
 }
 
 function CloudStorage:init()
+    --- @todo: Probably a good candidate for the new readSetting API
     self.cs_settings = self:readSettings()
     self.show_parent = self
     if self.item then

frontend/apps/filemanager/filemanager.lua

@@ -169,9 +169,13 @@ function FileManager:setupLayout()
         }
     }
 
-    local g_show_hidden = G_reader_settings:readSetting("show_hidden")
-    local show_hidden = g_show_hidden == nil and DSHOWHIDDENFILES or g_show_hidden
-    local show_unsupported = G_reader_settings:readSetting("show_unsupported")
+    local show_hidden
+    if G_reader_settings:has("show_hidden") then
+        show_hidden = G_reader_settings:isTrue("show_hidden")
+    else
+        show_hidden = DSHOWHIDDENFILES
+    end
+    local show_unsupported = G_reader_settings:isTrue("show_unsupported")
     local file_chooser = FileChooser:new{
         -- remember to adjust the height when new item is added to the group
         path = self.root_path,
@@ -760,7 +764,7 @@ end
 
 function FileManager:goHome()
     local home_dir = G_reader_settings:readSetting("home_dir")
-    if not home_dir or lfs.attributes(home_dir, "mode") ~= "directory"  then
+    if not home_dir or lfs.attributes(home_dir, "mode") ~= "directory" then
         -- Try some sane defaults, depending on platform
         home_dir = Device.home_dir
     end

frontend/apps/filemanager/filemanagerbookinfo.lua

@@ -67,7 +67,7 @@ function BookInfo:show(file, book_props)
     table.insert(kv_pairs, { _("Folder:"), BD.dirpath(filemanagerutil.abbreviate(directory)), separator = true })
 
     -- book_props may be provided if caller already has them available
-    -- but it may lack 'pages', that we may get from sidecar file
+    -- but it may lack "pages", that we may get from sidecar file
     if not book_props or not book_props.pages then
         -- check there is actually a sidecar file before calling DocSettings:open()
         -- that would create an empty sidecar directory
@@ -75,24 +75,24 @@ function BookInfo:show(file, book_props)
             local doc_settings = DocSettings:open(file)
             if doc_settings then
                 if not book_props then
-                    -- Files opened after 20170701 have a 'doc_props' setting with
-                    -- complete metadata and 'doc_pages' with accurate nb of pages
-                    book_props = doc_settings:readSetting('doc_props')
+                    -- Files opened after 20170701 have a "doc_props" setting with
+                    -- complete metadata and "doc_pages" with accurate nb of pages
+                    book_props = doc_settings:readSetting("doc_props")
                 end
                 if not book_props then
-                    -- File last opened before 20170701 may have a 'stats' setting
+                    -- File last opened before 20170701 may have a "stats" setting.
                     -- with partial metadata, or empty metadata if statistics plugin
                     -- was not enabled when book was read (we can guess that from
                     -- the fact that stats.page = 0)
-                    local stats = doc_settings:readSetting('stats')
+                    local stats = doc_settings:readSetting("stats")
                     if stats and stats.pages ~= 0 then
                         -- Let's use them as is (which was what was done before), even if
                         -- incomplete, to avoid expensive book opening
                         book_props = stats
                     end
                 end
-                -- Files opened after 20170701 have an accurate 'doc_pages' setting
-                local doc_pages = doc_settings:readSetting('doc_pages')
+                -- Files opened after 20170701 have an accurate "doc_pages" setting.
+                local doc_pages = doc_settings:readSetting("doc_pages")
                 if doc_pages and book_props then
                     book_props.pages = doc_pages
                 end
@@ -100,7 +100,7 @@ function BookInfo:show(file, book_props)
         end
     end
 
-    -- If still no book_props (book never opened or empty 'stats'), open the
+    -- If still no book_props (book never opened or empty "stats"), open the
     -- document to get them
     if not book_props then
         local document = DocumentRegistry:openDocument(file)

frontend/apps/filemanager/filemanagerfilesearcher.lua

@@ -95,10 +95,7 @@ end
 
 function FileSearcher:onShowFileSearch()
     local dummy = self.search_value
-    local enabled_search_home_dir = true
-    if not G_reader_settings:readSetting("home_dir") then
-        enabled_search_home_dir = false
-    end
+    local enabled_search_home_dir = G_reader_settings:has("home_dir")
     self.search_dialog = InputDialog:new{
         title = _("Search for books by filename"),
         input = self.search_value,

frontend/apps/filemanager/filemanagermenu.lua

@@ -236,18 +236,18 @@ function FileManagerMenu:setUpdateItemTable()
                     local current_state = _("Show new files in bold")
                     if G_reader_settings:readSetting("show_file_in_bold") == "opened" then
                         current_state = _("Show opened files in bold")
-                    elseif G_reader_settings:readSetting("show_file_in_bold") == false then
+                    elseif G_reader_settings:isFalse("show_file_in_bold") then
                         current_state = _("Show files in bold") -- with checkmark unchecked
                     end
                     -- Inform that this settings applies only to classic file chooser
                     current_state = T(_("(Classic file browser) %1"), current_state)
                     return current_state
                 end,
-                checked_func = function() return G_reader_settings:readSetting("show_file_in_bold") ~= false end,
+                checked_func = function() return not G_reader_settings:isFalse("show_file_in_bold") end,
                 sub_item_table = {
                     {
                         text = _("Don't show files in bold"),
-                        checked_func = function() return G_reader_settings:readSetting("show_file_in_bold") == false end,
+                        checked_func = function() return G_reader_settings:isFalse("show_file_in_bold") end,
                         callback = function()
                             G_reader_settings:saveSetting("show_file_in_bold", false)
                             self.ui:onRefresh()
@@ -264,7 +264,7 @@ function FileManagerMenu:setUpdateItemTable()
                     {
                         text = _("Show new (not yet opened) files in bold"),
                         checked_func = function()
-                            return G_reader_settings:readSetting("show_file_in_bold") ~= false and G_reader_settings:readSetting("show_file_in_bold") ~= "opened"
+                            return not G_reader_settings:isFalse("show_file_in_bold") and G_reader_settings:readSetting("show_file_in_bold") ~= "opened"
                         end,
                         callback = function()
                             G_reader_settings:delSetting("show_file_in_bold")
@@ -296,12 +296,12 @@ To:
             },
             {
                 text = _("Show filename in Open last/previous menu items"),
-                checked_func = function() return G_reader_settings:readSetting("open_last_menu_show_filename") end,
+                checked_func = function() return G_reader_settings:isTrue("open_last_menu_show_filename") end,
                 callback = function() G_reader_settings:flipNilOrFalse("open_last_menu_show_filename") end,
             },
             {
                 text = _("Auto-remove deleted or purged items from history"),
-                checked_func = function() return G_reader_settings:readSetting("autoremove_deleted_items_from_history") end,
+                checked_func = function() return G_reader_settings:isTrue("autoremove_deleted_items_from_history") end,
                 callback = function() G_reader_settings:flipNilOrFalse("autoremove_deleted_items_from_history") end,
                 separator = true,
             },
@@ -413,7 +413,7 @@ To:
                     else
                         dbg:setVerbose(false)
                         dbg:turnOff()
-                        G_reader_settings:flipFalse("debug_verbose")
+                        G_reader_settings:makeFalse("debug_verbose")
                     end
                 end,
             },
@@ -494,7 +494,7 @@ To:
                 G_reader_settings:saveSetting("dev_no_hw_dither", not Device.screen.hw_dithering)
                 -- Make sure SW dithering gets disabled when we enable HW dithering
                 if Device.screen.hw_dithering and Device.screen.sw_dithering then
-                    G_reader_settings:saveSetting("dev_no_sw_dither", true)
+                    G_reader_settings:makeTrue("dev_no_sw_dither")
                     Device.screen:toggleSWDithering(false)
                 end
                 UIManager:setDirty("all", "full")
@@ -515,7 +515,7 @@ To:
                 G_reader_settings:saveSetting("dev_no_sw_dither", not Device.screen.sw_dithering)
                 -- Make sure HW dithering gets disabled when we enable SW dithering
                 if Device.screen.hw_dithering and Device.screen.sw_dithering then
-                    G_reader_settings:saveSetting("dev_no_hw_dither", true)
+                    G_reader_settings:makeTrue("dev_no_hw_dither")
                     Device.screen:toggleHWDithering(false)
                 end
                 UIManager:setDirty("all", "full")
@@ -621,15 +621,15 @@ To:
     -- main menu tab
     self.menu_items.open_last_document = {
         text_func = function()
-            if not G_reader_settings:isTrue("open_last_menu_show_filename") or not G_reader_settings:readSetting("lastfile") then
+            if not G_reader_settings:isTrue("open_last_menu_show_filename") or G_reader_settings:hasNot("lastfile") then
                 return _("Open last document")
             end
             local last_file = G_reader_settings:readSetting("lastfile")
-            local path, file_name = util.splitFilePathName(last_file); -- luacheck: no unused
+            local path, file_name = util.splitFilePathName(last_file) -- luacheck: no unused
             return T(_("Last: %1"), BD.filename(file_name))
         end,
         enabled_func = function()
-            return G_reader_settings:readSetting("lastfile") ~= nil
+            return G_reader_settings:has("lastfile")
         end,
         callback = function()
             self:onOpenLastDoc()

frontend/apps/filemanager/filemanagershortcuts.lua

@@ -11,12 +11,13 @@ local util = require("ffi/util")
 local _ = require("gettext")
 local T = util.template
 
-local FileManagerShortcuts = InputContainer:extend{}
+local FileManagerShortcuts = InputContainer:extend{
+    folder_shortcuts = G_reader_settings:readSetting("folder_shortcuts", {}),
+}
 
 function FileManagerShortcuts:updateItemTable()
     local item_table = {}
-    local folder_shortcuts = G_reader_settings:readSetting("folder_shortcuts") or {}
-    for _, item in ipairs(folder_shortcuts) do
+    for _, item in ipairs(self.folder_shortcuts) do
         table.insert(item_table, {
             text = string.format("%s (%s)", item.text, item.folder),
             folder = item.folder,
@@ -107,7 +108,7 @@ function FileManagerShortcuts:addNewFolder()
 end
 
 function FileManagerShortcuts:addFolderFromInput(friendly_name, folder)
-    for __, item in ipairs(G_reader_settings:readSetting("folder_shortcuts") or {}) do
+    for __, item in ipairs(self.folder_shortcuts) do
         if item.text == friendly_name and item.folder == folder then
             UIManager:show(InfoMessage:new{
                 text = _("A shortcut to this folder already exists."),
@@ -115,12 +116,10 @@ function FileManagerShortcuts:addFolderFromInput(friendly_name, folder)
             return
         end
     end
-    local folder_shortcuts = G_reader_settings:readSetting("folder_shortcuts") or {}
-    table.insert(folder_shortcuts, {
+    table.insert(self.folder_shortcuts, {
         text = friendly_name,
         folder = folder,
     })
-    G_reader_settings:saveSetting("folder_shortcuts", folder_shortcuts)
     self:updateItemTable()
 end
 
@@ -193,25 +192,21 @@ function FileManagerShortcuts:editFolderShortcut(item)
 end
 
 function FileManagerShortcuts:renameFolderShortcut(item, new_name)
-    local folder_shortcuts = {}
-    for _, element in ipairs(G_reader_settings:readSetting("folder_shortcuts") or {}) do
+    for _, element in ipairs(self.folder_shortcuts) do
         if element.text == item.friendly_name and element.folder == item.folder then
             element.text = new_name
         end
-        table.insert(folder_shortcuts, element)
     end
-    G_reader_settings:saveSetting("folder_shortcuts", folder_shortcuts)
     self:updateItemTable()
 end
 
 function FileManagerShortcuts:deleteFolderShortcut(item)
-    local folder_shortcuts = {}
-    for _, element in ipairs(G_reader_settings:readSetting("folder_shortcuts") or {}) do
-        if element.text ~= item.friendly_name or element.folder ~= item.folder then
-            table.insert(folder_shortcuts, element)
+    for i = #self.folder_shortcuts, 1, -1 do
+        local element = self.folder_shortcuts[i]
+        if element.text == item.friendly_name and element.folder == item.folder then
+            table.remove(self.folder_shortcuts, i)
         end
     end
-    G_reader_settings:saveSetting("folder_shortcuts", folder_shortcuts)
     self:updateItemTable()
 end
 

frontend/apps/reader/modules/readerbookmark.lua

@@ -32,12 +32,12 @@ function ReaderBookmark:init()
         }
     end
 
-    if not G_reader_settings:readSetting("bookmarks_items_per_page") then
+    if G_reader_settings:hasNot("bookmarks_items_per_page") then
         -- The Bookmarks items per page and items' font size can now be
         -- configured. Previously, the ones set for the file browser
         -- were used. Initialize them from these ones.
         local items_per_page = G_reader_settings:readSetting("items_per_page")
-                                or self.bookmarks_items_per_page_default
+                            or self.bookmarks_items_per_page_default
         G_reader_settings:saveSetting("bookmarks_items_per_page", items_per_page)
         local items_font_size = G_reader_settings:readSetting("items_font_size")
         if items_font_size and items_font_size ~= Menu.getItemFontSize(items_per_page) then
@@ -186,7 +186,7 @@ end
 function ReaderBookmark:fixBookmarkSort(config)
     -- for backward compatibility, since previously bookmarks for credocuments
     -- are not well sorted. We need to do a whole sorting for at least once.
-    if not config:readSetting("bookmarks_sorted") then
+    if config:hasNot("bookmarks_sorted") then
         table.sort(self.bookmarks, function(a, b)
             return self:isBookmarkInPageOrder(a, b)
         end)
@@ -197,7 +197,7 @@ function ReaderBookmark:importSavedHighlight(config)
     local textmarks = config:readSetting("highlight") or {}
     -- import saved highlight once, because from now on highlight are added to
     -- bookmarks when they are created.
-    if not config:readSetting("highlights_imported") then
+    if config:hasNot("highlights_imported") then
         for page, marks in pairs(textmarks) do
             for _, mark in ipairs(marks) do
                 page = self.ui.document.info.has_pages and page or mark.pos0
@@ -228,8 +228,8 @@ end
 
 function ReaderBookmark:onSaveSettings()
     self.ui.doc_settings:saveSetting("bookmarks", self.bookmarks)
-    self.ui.doc_settings:saveSetting("bookmarks_sorted", true)
-    self.ui.doc_settings:saveSetting("highlights_imported", true)
+    self.ui.doc_settings:makeTrue("bookmarks_sorted")
+    self.ui.doc_settings:makeTrue("highlights_imported")
 end
 
 function ReaderBookmark:isCurrentPageBookmarked()

frontend/apps/reader/modules/readerconfig.lua

@@ -29,8 +29,9 @@ function ReaderConfig:init()
     if Device:isTouchDevice() then
         self:initGesListener()
     end
-    self.activation_menu = G_reader_settings:readSetting("activate_menu")
-    if self.activation_menu == nil then
+    if G_reader_settings:has("activate_menu") then
+        self.activation_menu = G_reader_settings:readSetting("activate_menu")
+    else
         self.activation_menu = "swipe_tap"
     end
 end

frontend/apps/reader/modules/readercoptlistener.lua

@@ -11,8 +11,9 @@ local _ = require("gettext")
 local ReaderCoptListener = EventListener:new{}
 
 function ReaderCoptListener:onReadSettings(config)
-    local view_mode = config:readSetting("copt_view_mode") or
-           G_reader_settings:readSetting("copt_view_mode") or 0 -- default to "page" mode
+    local view_mode = config:readSetting("copt_view_mode")
+                   or G_reader_settings:readSetting("copt_view_mode")
+                   or 0 -- default to "page" mode
     local view_mode_name = view_mode == 0 and "page" or "scroll"
     -- Let crengine know of the view mode before rendering, as it can
     -- cause a rendering change (2-pages would become 1-page in

frontend/apps/reader/modules/readerdictionary.lua

@@ -58,7 +58,6 @@ end
 local ReaderDictionary = InputContainer:new{
     data_dir = nil,
     dict_window_list = {},
-    disable_lookup_history = G_reader_settings:isTrue("disable_lookup_history"),
     lookup_msg = _("Searching dictionary for:\n%1"),
 }
 
@@ -96,6 +95,10 @@ local function getDictionaryFixHtmlFunc(path)
 end
 
 function ReaderDictionary:init()
+    self.disable_lookup_history = G_reader_settings:isTrue("disable_lookup_history")
+    self.dicts_order = G_reader_settings:readSetting("dicts_order", {})
+    self.dicts_disabled = G_reader_settings:readSetting("dicts_disabled", {})
+
     self.ui.menu:registerToMainMenu(self)
     self.data_dir = STARDICT_DATA_DIR or
         os.getenv("STARDICT_DATA_DIR") or
@@ -140,19 +143,7 @@ function ReaderDictionary:init()
             end
         end
         logger.dbg("found", #available_ifos, "dictionaries")
-
-        if not G_reader_settings:readSetting("dicts_order") then
-            G_reader_settings:saveSetting("dicts_order", {})
-        end
-
         self:sortAvailableIfos()
-
-        if not G_reader_settings:readSetting("dicts_disabled") then
-            -- Create an empty dict for this setting, so that we can
-            -- access and update it directly through G_reader_settings
-            -- and it will automatically be saved.
-            G_reader_settings:saveSetting("dicts_disabled", {})
-        end
     end
     -- Prepare the -u options to give to sdcv the dictionary order and if some are disabled
     self:updateSdcvDictNamesOptions()
@@ -163,11 +154,9 @@ function ReaderDictionary:init()
 end
 
 function ReaderDictionary:sortAvailableIfos()
-    local dicts_order = G_reader_settings:readSetting("dicts_order")
-
     table.sort(available_ifos, function(lifo, rifo)
-        local lord = dicts_order[lifo.file]
-        local rord = dicts_order[rifo.file]
+        local lord = self.dicts_order[lifo.file]
+        local rord = self.dicts_order[rifo.file]
 
         -- Both ifos without an explicit position -> lexical comparison
         if lord == rord then
@@ -468,9 +457,8 @@ function ReaderDictionary:getNumberOfDictionaries()
     local nb_available = #available_ifos
     local nb_enabled = 0
     local nb_disabled = 0
-    local dicts_disabled = G_reader_settings:readSetting("dicts_disabled")
     for _, ifo in pairs(available_ifos) do
-        if dicts_disabled[ifo.file] then
+        if self.dicts_disabled[ifo.file] then
             nb_disabled = nb_disabled + 1
         else
             nb_enabled = nb_enabled + 1
@@ -526,7 +514,7 @@ end
 
 function ReaderDictionary:showDictionariesMenu(changed_callback)
     -- Work on local copy, save to settings only when SortWidget is closed with the accept button
-    local dicts_disabled = util.tableDeepCopy(G_reader_settings:readSetting("dicts_disabled"))
+    local dicts_disabled = util.tableDeepCopy(self.dicts_disabled)
 
     local sort_items = {}
     for _, ifo in pairs(available_ifos) do
@@ -550,15 +538,17 @@ function ReaderDictionary:showDictionariesMenu(changed_callback)
         title = _("Manage installed dictionaries"),
         item_table = sort_items,
         callback = function()
-            -- Save local copy of dicts_disabled
-            G_reader_settings:saveSetting("dicts_disabled", dicts_disabled)
+            -- Update both references to point to that new object
+            self.dicts_disabled = dicts_disabled
+            G_reader_settings:saveSetting("dicts_disabled", self.dicts_disabled)
 
             -- Write back the sorted items to dicts_order
             local dicts_order = {}
             for i, sort_item in pairs(sort_items) do
                 dicts_order[sort_item.ifo.file] = i
             end
-            G_reader_settings:saveSetting("dicts_order", dicts_order)
+            self.dicts_order = dicts_order
+            G_reader_settings:saveSetting("dicts_order", self.dicts_order)
 
             self:sortAvailableIfos()
 
@@ -1058,8 +1048,9 @@ function ReaderDictionary:onReadSettings(config)
     if #self.preferred_dictionaries > 0 then
         self:updateSdcvDictNamesOptions()
     end
-    self.disable_fuzzy_search = config:readSetting("disable_fuzzy_search")
-    if self.disable_fuzzy_search == nil then
+    if config:has("disable_fuzzy_search") then
+        self.disable_fuzzy_search = config:isTrue("disable_fuzzy_search")
+    else
         self.disable_fuzzy_search = G_reader_settings:isTrue("disable_fuzzy_search")
     end
 end
@@ -1118,13 +1109,13 @@ The current default (★) is enabled.]])
             return disable_fuzzy_search and _("Disable (★)") or _("Disable")
         end,
         choice1_callback = function()
-            G_reader_settings:saveSetting("disable_fuzzy_search", true)
+            G_reader_settings:makeTrue("disable_fuzzy_search")
         end,
         choice2_text_func = function()
             return disable_fuzzy_search and _("Enable") or _("Enable (★)")
         end,
         choice2_callback = function()
-            G_reader_settings:saveSetting("disable_fuzzy_search", false)
+            G_reader_settings:makeFalse("disable_fuzzy_search")
         end,
     })
 end

frontend/apps/reader/modules/readerdogear.lua

@@ -56,15 +56,15 @@ end
 function ReaderDogear:onReadSettings(config)
     if not self.ui.document.info.has_pages then
         -- Adjust to CreDocument margins (as done in ReaderTypeset)
-        local h_margins = config:readSetting("copt_h_page_margins") or
-            G_reader_settings:readSetting("copt_h_page_margins") or
-            DCREREADER_CONFIG_H_MARGIN_SIZES_MEDIUM
-        local t_margin = config:readSetting("copt_t_page_margin") or
-            G_reader_settings:readSetting("copt_t_page_margin") or
-            DCREREADER_CONFIG_T_MARGIN_SIZES_LARGE
-        local b_margin = config:readSetting("copt_b_page_margin") or
-            G_reader_settings:readSetting("copt_b_page_margin") or
-            DCREREADER_CONFIG_B_MARGIN_SIZES_LARGE
+        local h_margins = config:readSetting("copt_h_page_margins")
+                       or G_reader_settings:readSetting("copt_h_page_margins")
+                       or DCREREADER_CONFIG_H_MARGIN_SIZES_MEDIUM
+        local t_margin = config:readSetting("copt_t_page_margin")
+                      or G_reader_settings:readSetting("copt_t_page_margin")
+                      or DCREREADER_CONFIG_T_MARGIN_SIZES_LARGE
+        local b_margin = config:readSetting("copt_b_page_margin")
+                      or G_reader_settings:readSetting("copt_b_page_margin")
+                      or DCREREADER_CONFIG_B_MARGIN_SIZES_LARGE
         local margins = { h_margins[1], t_margin, h_margins[2], b_margin }
         self:onSetPageMargins(margins)
     end

frontend/apps/reader/modules/readerfont.lua

@@ -108,48 +108,55 @@ end
 
 function ReaderFont:onReadSettings(config)
     self.font_face = config:readSetting("font_face")
-            or G_reader_settings:readSetting("cre_font")
-            or self.ui.document.default_font
+                  or G_reader_settings:readSetting("cre_font")
+                  or self.ui.document.default_font
     self.ui.document:setFontFace(self.font_face)
 
     self.header_font_face = config:readSetting("header_font_face")
-            or G_reader_settings:readSetting("header_font")
-            or self.ui.document.header_font
+                         or G_reader_settings:readSetting("header_font")
+                         or self.ui.document.header_font
     self.ui.document:setHeaderFont(self.header_font_face)
 
     self.font_size = config:readSetting("font_size")
-            or G_reader_settings:readSetting("copt_font_size")
-            or DCREREADER_CONFIG_DEFAULT_FONT_SIZE or 22
+                  or G_reader_settings:readSetting("copt_font_size")
+                  or DCREREADER_CONFIG_DEFAULT_FONT_SIZE
+                  or 22
     self.ui.document:setFontSize(Screen:scaleBySize(self.font_size))
 
     self.font_embolden = config:readSetting("font_embolden")
-            or G_reader_settings:readSetting("copt_font_weight") or 0
+                      or G_reader_settings:readSetting("copt_font_weight")
+                      or 0
     self.ui.document:toggleFontBolder(self.font_embolden)
 
     self.font_hinting = config:readSetting("font_hinting")
-            or G_reader_settings:readSetting("copt_font_hinting") or 2 -- auto (default in cre.cpp)
+                     or G_reader_settings:readSetting("copt_font_hinting")
+                     or 2 -- auto (default in cre.cpp)
     self.ui.document:setFontHinting(self.font_hinting)
 
     self.font_kerning = config:readSetting("font_kerning")
-            or G_reader_settings:readSetting("copt_font_kerning") or 3 -- harfbuzz (slower, but needed for proper arabic)
+                     or G_reader_settings:readSetting("copt_font_kerning")
+                     or 3 -- harfbuzz (slower, but needed for proper arabic)
     self.ui.document:setFontKerning(self.font_kerning)
 
     self.word_spacing = config:readSetting("word_spacing")
-        or G_reader_settings:readSetting("copt_word_spacing") or {95, 75}
+                     or G_reader_settings:readSetting("copt_word_spacing")
+                     or {95, 75}
     self.ui.document:setWordSpacing(self.word_spacing)
 
     self.word_expansion = config:readSetting("word_expansion")
-        or G_reader_settings:readSetting("copt_word_expansion") or 0
+                       or G_reader_settings:readSetting("copt_word_expansion")
+                       or 0
     self.ui.document:setWordExpansion(self.word_expansion)
 
     self.line_space_percent = config:readSetting("line_space_percent")
-            or G_reader_settings:readSetting("copt_line_spacing")
-            or DCREREADER_CONFIG_LINE_SPACE_PERCENT_MEDIUM
+                           or G_reader_settings:readSetting("copt_line_spacing")
+                           or DCREREADER_CONFIG_LINE_SPACE_PERCENT_MEDIUM
     self.ui.document:setInterlineSpacePercent(self.line_space_percent)
 
     self.gamma_index = config:readSetting("gamma_index")
-            or G_reader_settings:readSetting("copt_font_gamma")
-            or DCREREADER_CONFIG_DEFAULT_FONT_GAMMA or 15 -- gamma = 1.0
+                    or G_reader_settings:readSetting("copt_font_gamma")
+                    or DCREREADER_CONFIG_DEFAULT_FONT_GAMMA
+                    or 15 -- gamma = 1.0
     self.ui.document:setGammaIndex(self.gamma_index)
 
     -- Dirty hack: we have to add following call in order to set
@@ -439,8 +446,8 @@ function ReaderFont:buildFontsTestDocument()
         f:close()
     end
     local dir = G_reader_settings:readSetting("home_dir")
-    if not dir then dir = require("apps/filemanager/filemanagerutil").getDefaultDir() end
-    if not dir then dir = "." end
+             or require("apps/filemanager/filemanagerutil").getDefaultDir()
+             or "."
     local font_test_final_path = dir .. "/" .. FONT_TEST_FINAL_FILENAME
     f = io.open(font_test_final_path, "w")
     if not f then return end

frontend/apps/reader/modules/readerfooter.lua

@@ -387,7 +387,7 @@ local ReaderFooter = WidgetContainer:extend{
 }
 
 function ReaderFooter:init()
-    self.settings = G_reader_settings:readSetting("footer") or {
+    self.settings = G_reader_settings:readSetting("footer", {
         -- enable progress bar by default
         -- disable_progress_bar = true,
         disabled = false,
@@ -414,7 +414,7 @@ function ReaderFooter:init()
         text_font_bold = false,
         container_height = DMINIBAR_CONTAINER_HEIGHT,
         container_bottom_padding = 1, -- unscaled_size_check: ignore
-    }
+    })
 
     -- Remove items not supported by the current device
     if not Device:hasFastWifiStatusQuery() then
@@ -889,7 +889,6 @@ function ReaderFooter:addToMainMenu(menu_items)
             end,
             callback = function()
                 self.settings[option] = not self.settings[option]
-                G_reader_settings:saveSetting("footer", self.settings)
                 -- We only need to send a SetPageBottomMargin event when we truly affect the margin
                 local should_signal = false
                 -- only case that we don't need a UI update is enable/disable
@@ -976,7 +975,6 @@ function ReaderFooter:addToMainMenu(menu_items)
                                 self.mode_index[i] = sort_item.item_table[i].label
                             end
                             self.settings.order = self.mode_index
-                            G_reader_settings:saveSetting("footer", self.settings)
                             self:updateFooterTextGenerator()
                             self:onUpdateFooter()
                             UIManager:setDirty(nil, "ui")
@@ -994,7 +992,6 @@ function ReaderFooter:addToMainMenu(menu_items)
                 end,
                 callback = function()
                     self.settings.auto_refresh_time = not self.settings.auto_refresh_time
-                    G_reader_settings:saveSetting("footer", self.settings)
                     self:rescheduleFooterAutoRefreshIfNeeded()
                 end
             },
@@ -1035,7 +1032,6 @@ function ReaderFooter:addToMainMenu(menu_items)
                 end,
                 callback = function()
                     self.settings.skim_widget_on_hold = not self.settings.skim_widget_on_hold
-                    G_reader_settings:saveSetting("footer", self.settings)
                 end,
             },
             {
@@ -1857,7 +1853,7 @@ function ReaderFooter:getAvgTimePerPage()
 end
 
 function ReaderFooter:getDataFromStatistics(title, pages)
-    local sec = "N/A"
+    local sec = _("N/A")
     local average_time_per_page = self:getAvgTimePerPage()
     if average_time_per_page then
         if self.settings.duration_format == "classic" then
@@ -2065,9 +2061,9 @@ end
 
 function ReaderFooter:onReadSettings(config)
     if not self.ui.document.info.has_pages then
-        local h_margins = config:readSetting("copt_h_page_margins") or
-            G_reader_settings:readSetting("copt_h_page_margins") or
-            DCREREADER_CONFIG_H_MARGIN_SIZES_MEDIUM
+        local h_margins = config:readSetting("copt_h_page_margins")
+                       or G_reader_settings:readSetting("copt_h_page_margins")
+                       or DCREREADER_CONFIG_H_MARGIN_SIZES_MEDIUM
         self.book_margins_footer_width = math.floor((h_margins[1] + h_margins[2])/2)
     end
 end

frontend/apps/reader/modules/readerhighlight.lua

@@ -1175,13 +1175,13 @@ function ReaderHighlight:onCycleHighlightAction()
         dictionary = "search",
         search = nil,
     }
-    local current_action = G_reader_settings:readSetting("default_highlight_action")
-    if not current_action then
+    if G_reader_settings:hasNot("default_highlight_action") then
         G_reader_settings:saveSetting("default_highlight_action", "highlight")
         UIManager:show(Notification:new{
             text = _("Default highlight action changed to 'highlight'."),
         })
     else
+        local current_action = G_reader_settings:readSetting("default_highlight_action")
         local next_action = next_actions[current_action]
         G_reader_settings:saveSetting("default_highlight_action", next_action)
         UIManager:show(Notification:new{
@@ -1446,23 +1446,25 @@ end
 
 function ReaderHighlight:onReadSettings(config)
     self.view.highlight.saved_drawer = config:readSetting("highlight_drawer") or self.view.highlight.saved_drawer
-    local disable_highlight = config:readSetting("highlight_disabled")
-    if disable_highlight == nil then
-        disable_highlight = G_reader_settings:readSetting("highlight_disabled") or false
+    if config:has("highlight_disabled") then
+        self.view.highlight.disabled = config:isTrue("highlight_disabled")
+    else
+        self.view.highlight.disabled = G_reader_settings:isTrue("highlight_disabled")
     end
-    self.view.highlight.disabled = disable_highlight
 
     -- panel zoom settings isn't supported in EPUB
     if self.document.info.has_pages then
         local ext = util.getFileNameSuffix(self.ui.document.file)
         G_reader_settings:initializeExtSettings("panel_zoom_enabled", {cbz = true, cbt = true})
         G_reader_settings:initializeExtSettings("panel_zoom_fallback_to_text_selection", {pdf = true})
-        self.panel_zoom_enabled = config:readSetting("panel_zoom_enabled")
-        if self.panel_zoom_enabled == nil then
+        if config:has("panel_zoom_enabled") then
+            self.panel_zoom_enabled = config:isTrue("panel_zoom_enabled")
+        else
             self.panel_zoom_enabled = G_reader_settings:getSettingForExt("panel_zoom_enabled", ext) or false
         end
-        self.panel_zoom_fallback_to_text_selection = config:readSetting("panel_zoom_fallback_to_text_selection")
-        if self.panel_zoom_fallback_to_text_selection == nil then
+        if config:has("panel_zoom_fallback_to_text_selection") then
+            self.panel_zoom_fallback_to_text_selection = config:isTrue("panel_zoom_fallback_to_text_selection")
+        else
             self.panel_zoom_fallback_to_text_selection = G_reader_settings:getSettingForExt("panel_zoom_fallback_to_text_selection", ext) or false
         end
     end
@@ -1493,13 +1495,13 @@ function ReaderHighlight:toggleDefault()
             return highlight_disabled and _("Disable (★)") or _("Disable")
         end,
         choice1_callback = function()
-            G_reader_settings:saveSetting("highlight_disabled", true)
+            G_reader_settings:makeTrue("highlight_disabled")
         end,
         choice2_text_func = function()
             return highlight_disabled and _("Enable") or _("Enable (★)")
         end,
         choice2_callback = function()
-            G_reader_settings:saveSetting("highlight_disabled", false)
+            G_reader_settings:makeFalse("highlight_disabled")
         end,
     })
 end

frontend/apps/reader/modules/readerkoptlistener.lua

@@ -16,15 +16,17 @@ end
 
 function ReaderKoptListener:onReadSettings(config)
     -- normal zoom mode is zoom mode used in non-reflow mode.
-    local normal_zoom_mode = config:readSetting("normal_zoom_mode") or
-                    G_reader_settings:readSetting("zoom_mode") or "page"
+    local normal_zoom_mode = config:readSetting("normal_zoom_mode")
+                          or G_reader_settings:readSetting("zoom_mode")
+                          or "page"
     normal_zoom_mode = util.arrayContains(ReaderZooming.available_zoom_modes, normal_zoom_mode)
-                    and normal_zoom_mode
+                   and normal_zoom_mode
                     or "page"
     self.normal_zoom_mode = normal_zoom_mode
     self:setZoomMode(normal_zoom_mode)
-    self.document.configurable.contrast = config:readSetting("kopt_contrast") or
-                    G_reader_settings:readSetting("kopt_contrast") or 1.0
+    self.document.configurable.contrast = config:readSetting("kopt_contrast")
+                                       or G_reader_settings:readSetting("kopt_contrast")
+                                       or 1.0
     self.ui:handleEvent(Event:new("GammaUpdate", 1/self.document.configurable.contrast))
     -- since K2pdfopt v2.21 negative value of word spacing is also used, for config
     -- compatability we should manually change previous -1 to a more reasonable -0.2

frontend/apps/reader/modules/readerlink.lua

@@ -326,7 +326,7 @@ The recommended value is -2.]]),
                     end
                     return spin_widget
                 end
-                local show_absolute_font_size_widget = G_reader_settings:readSetting("footnote_popup_absolute_font_size") ~= nil
+                local show_absolute_font_size_widget = G_reader_settings:has("footnote_popup_absolute_font_size")
                 spin_widget = get_font_size_widget(show_absolute_font_size_widget)
                 UIManager:show(spin_widget)
             end,

frontend/apps/reader/modules/readermenu.lua

@@ -71,8 +71,9 @@ function ReaderMenu:init()
             end
         end
     end
-    self.activation_menu = G_reader_settings:readSetting("activate_menu")
-    if self.activation_menu == nil then
+    if G_reader_settings:has("activate_menu") then
+        self.activation_menu = G_reader_settings:readSetting("activate_menu")
+    else
         self.activation_menu = "swipe_tap"
     end
 end
@@ -190,16 +191,16 @@ function ReaderMenu:setUpdateItemTable()
             text = _("Exclude this book's cover from screensaver"),
             enabled_func = function()
                 return not (self.ui == nil or self.ui.document == nil)
-                    and G_reader_settings:readSetting('screensaver_type') == "cover"
+                    and G_reader_settings:readSetting("screensaver_type") == "cover"
             end,
             checked_func = function()
-                return self.ui and self.ui.doc_settings and self.ui.doc_settings:readSetting("exclude_screensaver") == true
+                return self.ui and self.ui.doc_settings and self.ui.doc_settings:isTrue("exclude_screensaver")
             end,
             callback = function()
-                if Screensaver:excluded() then
-                    self.ui.doc_settings:saveSetting("exclude_screensaver", false)
+                if Screensaver:isExcluded() then
+                    self.ui.doc_settings:makeFalse("exclude_screensaver")
                 else
-                    self.ui.doc_settings:saveSetting("exclude_screensaver", true)
+                    self.ui.doc_settings:makeTrue("exclude_screensaver")
                 end
                 self.ui:saveSettings()
             end,

frontend/apps/reader/modules/readerpagemap.lua

@@ -88,18 +88,20 @@ function ReaderPageMap:resetLayout()
 end
 
 function ReaderPageMap:onReadSettings(config)
-    local h_margins = config:readSetting("copt_h_page_margins") or
-        G_reader_settings:readSetting("copt_h_page_margins") or
-        DCREREADER_CONFIG_H_MARGIN_SIZES_MEDIUM
+    local h_margins = config:readSetting("copt_h_page_margins")
+                   or G_reader_settings:readSetting("copt_h_page_margins")
+                   or DCREREADER_CONFIG_H_MARGIN_SIZES_MEDIUM
     self.max_left_label_width = Screen:scaleBySize(h_margins[1])
     self.max_right_label_width = Screen:scaleBySize(h_margins[2])
 
-    self.show_page_labels = config:readSetting("pagemap_show_page_labels")
-    if self.show_page_labels == nil then
+    if config:has("pagemap_show_page_labels") then
+        self.show_page_labels = config:isTrue("pagemap_show_page_labels")
+    else
         self.show_page_labels = G_reader_settings:nilOrTrue("pagemap_show_page_labels")
     end
-    self.use_page_labels = config:readSetting("pagemap_use_page_labels")
-    if self.use_page_labels == nil then
+    if config:has("pagemap_use_page_labels") then
+        self.use_page_labels = config:isTrue("pagemap_use_page_labels")
+    else
         self.use_page_labels = G_reader_settings:isTrue("pagemap_use_page_labels")
     end
 end
@@ -352,14 +354,14 @@ function ReaderPageMap:addToMainMenu(menu_items)
                             return use_page_labels and _("Renderer") or _("Renderer (★)")
                         end,
                         choice1_callback = function()
-                             G_reader_settings:saveSetting("pagemap_use_page_labels", false)
+                             G_reader_settings:makeFalse("pagemap_use_page_labels")
                              if touchmenu_instance then touchmenu_instance:updateItems() end
                         end,
                         choice2_text_func = function()
                             return use_page_labels and _("Reference (★)") or _("Reference")
                         end,
                         choice2_callback = function()
-                            G_reader_settings:saveSetting("pagemap_use_page_labels", true)
+                            G_reader_settings:makeTrue("pagemap_use_page_labels")
                             if touchmenu_instance then touchmenu_instance:updateItems() end
                         end,
                     })
@@ -385,14 +387,14 @@ function ReaderPageMap:addToMainMenu(menu_items)
                             return show_page_labels and _("Hide") or _("Hide (★)")
                         end,
                         choice1_callback = function()
-                             G_reader_settings:saveSetting("pagemap_show_page_labels", false)
+                             G_reader_settings:makeFalse("pagemap_show_page_labels")
                              if touchmenu_instance then touchmenu_instance:updateItems() end
                         end,
                         choice2_text_func = function()
                             return show_page_labels and _("Show (★)") or _("Show")
                         end,
                         choice2_callback = function()
-                            G_reader_settings:saveSetting("pagemap_show_page_labels", true)
+                            G_reader_settings:makeTrue("pagemap_show_page_labels")
                             if touchmenu_instance then touchmenu_instance:updateItems() end
                         end,
                     })

frontend/apps/reader/modules/readerpaging.lua

@@ -184,14 +184,16 @@ end
 function ReaderPaging:onReadSettings(config)
     self.page_positions = config:readSetting("page_positions") or {}
     self:_gotoPage(config:readSetting("last_page") or 1)
-    self.show_overlap_enable = config:readSetting("show_overlap_enable")
-    if self.show_overlap_enable == nil then
+    if config:has("show_overlap_enable") then
+        self.show_overlap_enable = config:isTrue("show_overlap_enable")
+    else
         self.show_overlap_enable = DSHOWOVERLAP
     end
     self.flipping_zoom_mode = config:readSetting("flipping_zoom_mode") or "page"
-    self.flipping_scroll_mode = config:readSetting("flipping_scroll_mode") or false
-    self.inverse_reading_order = config:readSetting("inverse_reading_order")
-    if self.inverse_reading_order == nil then
+    self.flipping_scroll_mode = config:isTrue("flipping_scroll_mode")
+    if config:has("inverse_reading_order") then
+        self.inverse_reading_order = config:isTrue("inverse_reading_order")
+    else
         self.inverse_reading_order = G_reader_settings:isTrue("inverse_reading_order")
     end
     for _, v in ipairs(ReaderZooming.zoom_pan_settings) do
@@ -266,14 +268,14 @@ function ReaderPaging:addToMainMenu(menu_items)
                     return inverse_reading_order and _("LTR") or _("LTR (★)")
                 end,
                 choice1_callback = function()
-                     G_reader_settings:saveSetting("inverse_reading_order", false)
+                     G_reader_settings:makeFalse("inverse_reading_order")
                      if touchmenu_instance then touchmenu_instance:updateItems() end
                 end,
                 choice2_text_func = function()
                     return inverse_reading_order and _("RTL (★)") or _("RTL")
                 end,
                 choice2_callback = function()
-                    G_reader_settings:saveSetting("inverse_reading_order", true)
+                    G_reader_settings:makeTrue("inverse_reading_order")
                     if touchmenu_instance then touchmenu_instance:updateItems() end
                 end,
             })

frontend/apps/reader/modules/readerrolling.lua

@@ -139,9 +139,9 @@ function ReaderRolling:onReadSettings(config)
     -- and highlights with old XPATHs.
     -- (EPUB will use the same correct DOM code no matter what DOM version
     -- we request here.)
-    if not config:readSetting("cre_dom_version") then
+    if config:hasNot("cre_dom_version") then
         -- Not previously set, guess which DOM version to use
-        if config:readSetting("last_xpointer") then
+        if config:has("last_xpointer") then
             -- We have a last_xpointer: this book was previously opened
             -- with possibly a very old version: request the oldest
             config:saveSetting("cre_dom_version", self.ui.document:getOldestDomVersion())
@@ -166,7 +166,7 @@ function ReaderRolling:onReadSettings(config)
         self.ui.typeset:ensureSanerBlockRenderingFlags()
         -- And check if we can migrate to a newest DOM version after
         -- the book is loaded (unless the user told us not to).
-        if not config:readSetting("cre_keep_old_dom_version") then
+        if config:nilOrFalse("cre_keep_old_dom_version") then
             self.ui:registerPostReadyCallback(function()
                 self:checkXPointersAndProposeDOMVersionUpgrade()
             end)
@@ -209,13 +209,15 @@ function ReaderRolling:onReadSettings(config)
             end
         end
     end
-    self.show_overlap_enable = config:readSetting("show_overlap_enable")
-    if self.show_overlap_enable == nil then
+    if config:has("show_overlap_enable") then
+        self.show_overlap_enable = config:isTrue("show_overlap_enable")
+    else
         self.show_overlap_enable = DSHOWOVERLAP
     end
 
-    self.inverse_reading_order = config:readSetting("inverse_reading_order")
-    if self.inverse_reading_order == nil then
+    if config:has("inverse_reading_order") then
+        self.inverse_reading_order = config:isTrue("inverse_reading_order")
+    else
         self.inverse_reading_order = G_reader_settings:isTrue("inverse_reading_order")
     end
 
@@ -229,8 +231,9 @@ function ReaderRolling:onReadSettings(config)
         G_reader_settings:readSetting("copt_visible_pages") or 1
     self.ui.document:setVisiblePageCount(self.visible_pages)
 
-    self.hide_nonlinear_flows = config:readSetting("hide_nonlinear_flows")
-    if self.hide_nonlinear_flows == nil then
+    if config:has("hide_nonlinear_flows") then
+        self.hide_nonlinear_flows = config:isTrue("hide_nonlinear_flows")
+    else
         self.hide_nonlinear_flows = G_reader_settings:isTrue("hide_nonlinear_flows")
     end
     self.ui.document:setHideNonlinearFlows(self.hide_nonlinear_flows)
@@ -296,7 +299,7 @@ end
 
 function ReaderRolling:onSaveSettings()
     -- remove last_percent config since its deprecated
-    self.ui.doc_settings:saveSetting("last_percent", nil)
+    self.ui.doc_settings:delSetting("last_percent")
     self.ui.doc_settings:saveSetting("last_xpointer", self.xpointer)
     -- in scrolling mode, the document may already be closed,
     -- so we have to check the condition to avoid crash function self:getLastPercent()
@@ -395,14 +398,14 @@ function ReaderRolling:addToMainMenu(menu_items)
                     return inverse_reading_order and _("LTR") or _("LTR (★)")
                 end,
                 choice1_callback = function()
-                     G_reader_settings:saveSetting("inverse_reading_order", false)
+                     G_reader_settings:makeFalse("inverse_reading_order")
                      if touchmenu_instance then touchmenu_instance:updateItems() end
                 end,
                 choice2_text_func = function()
                     return inverse_reading_order and _("RTL (★)") or _("RTL")
                 end,
                 choice2_callback = function()
-                    G_reader_settings:saveSetting("inverse_reading_order", true)
+                    G_reader_settings:makeTrue("inverse_reading_order")
                     if touchmenu_instance then touchmenu_instance:updateItems() end
                 end,
             })
@@ -644,8 +647,10 @@ function ReaderRolling:onGotoXPointer(xp, marker_xp)
     --   followed_link_marker = true: maker shown and not auto removed
     --   followed_link_marker = <number>: removed after <number> seconds
     -- (no real need for a menu item, the default is the finest)
-    local marker_setting = G_reader_settings:readSetting("followed_link_marker")
-    if marker_setting == nil then
+    local marker_setting
+    if G_reader_settings:has("followed_link_marker") then
+        marker_setting = G_reader_settings:readSetting("followed_link_marker")
+    else
         marker_setting = 1 -- default is: shown and removed after 1 second
     end
 
@@ -1279,11 +1284,14 @@ function ReaderRolling:checkXPointersAndProposeDOMVersionUpgrade()
         -- Switch to default block rendering mode if this book has it set to "legacy",
         -- unless the user had set the global mode to be "legacy".
         -- (see ReaderTypeset:onReadSettings() for the logic of block_rendering_mode)
-        local g_block_rendering_mode = G_reader_settings:readSetting("copt_block_rendering_mode")
+        local g_block_rendering_mode
+        if G_reader_settings:has("copt_block_rendering_mode") then
+            g_block_rendering_mode = G_reader_settings:readSetting("copt_block_rendering_mode")
+        else
+            -- nil means: use default
+            g_block_rendering_mode = 3 -- default in ReaderTypeset:onReadSettings()
+        end
         if g_block_rendering_mode ~= 0 then -- default is not "legacy"
-            if not g_block_rendering_mode then -- nil means: use default
-                g_block_rendering_mode = 3 -- default in ReaderTypeset:onReadSettings()
-            end
             -- This setting is actually saved by self.ui.document.configurable
             local block_rendering_mode = self.ui.document.configurable.block_rendering_mode
             if block_rendering_mode == 0 then
@@ -1343,7 +1351,7 @@ Note that %1 (out of %2) xpaths from your bookmarks and highlights have been nor
         }},
         cancel_text = _("Not for this book"),
         cancel_callback = function()
-            self.ui.doc_settings:saveSetting("cre_keep_old_dom_version", true)
+            self.ui.doc_settings:makeTrue("cre_keep_old_dom_version")
         end,
         ok_text = _("Upgrade now"),
         ok_callback = function()

frontend/apps/reader/modules/readerstyletweak.lua

@@ -327,7 +327,7 @@ function ReaderStyleTweak:updateCssText(apply)
 end
 
 function ReaderStyleTweak:onReadSettings(config)
-    self.enabled = not (config:readSetting("style_tweaks_enabled") == false)
+    self.enabled = config:nilOrTrue("style_tweaks_enabled")
     self.doc_tweaks = config:readSetting("style_tweaks") or {}
     -- Default globally enabled style tweaks (for new installations)
     -- are defined in css_tweaks.lua
@@ -342,7 +342,7 @@ function ReaderStyleTweak:onSaveSettings()
     if self.enabled then
         self.ui.doc_settings:delSetting("style_tweaks_enabled")
     else
-        self.ui.doc_settings:saveSetting("style_tweaks_enabled", false)
+        self.ui.doc_settings:makeFalse("style_tweaks_enabled")
     end
     self.ui.doc_settings:saveSetting("style_tweaks", util.tableSize(self.doc_tweaks) > 0 and self.doc_tweaks or nil)
     G_reader_settings:saveSetting("style_tweaks", self.global_tweaks)

frontend/apps/reader/modules/readertoc.lua

@@ -41,12 +41,12 @@ function ReaderToc:init()
         }
     end
 
-    if not G_reader_settings:readSetting("toc_items_per_page") then
+    if G_reader_settings:hasNot("toc_items_per_page") then
         -- The TOC items per page and items' font size can now be
         -- configured. Previously, the ones set for the file browser
         -- were used. Initialize them from these ones.
         local items_per_page = G_reader_settings:readSetting("items_per_page")
-                                or self.toc_items_per_page_default
+                            or self.toc_items_per_page_default
         G_reader_settings:saveSetting("toc_items_per_page", items_per_page)
         local items_font_size = G_reader_settings:readSetting("items_font_size")
         if items_font_size and items_font_size ~= Menu.getItemFontSize(items_per_page) then
@@ -137,7 +137,7 @@ end
 function ReaderToc:fillToc()
     if self.toc then return end
     if self.ui.document:canHaveAlternativeToc() then
-        if self.ui.doc_settings:readSetting("alternative_toc") then
+        if self.ui.doc_settings:isTrue("alternative_toc") then
             -- (if the document has a cache, the previously built alternative
             -- TOC was saved and has been reloaded, and this will be avoided)
             if not self.ui.document:isTocAlternativeToc() then
@@ -900,7 +900,7 @@ See Style tweaks → Miscellaneous → Alternative ToC hints.]]),
                             self:resetToc()
                             self.toc_ticks_ignored_levels = {} -- reset this
                             self.ui.document:buildAlternativeToc()
-                            self.ui.doc_settings:saveSetting("alternative_toc", true)
+                            self.ui.doc_settings:makeTrue("alternative_toc")
                             self:onShowToc()
                             self.view.footer:setTocMarkers(true)
                             self.view.footer:onUpdateFooter()

frontend/apps/reader/modules/readertypeset.lua

@@ -22,13 +22,15 @@ function ReaderTypeset:init()
 end
 
 function ReaderTypeset:onReadSettings(config)
-    self.css = config:readSetting("css") or G_reader_settings:readSetting("copt_css")
-                or self.ui.document.default_css
+    self.css = config:readSetting("css")
+            or G_reader_settings:readSetting("copt_css")
+            or self.ui.document.default_css
     local tweaks_css = self.ui.styletweak:getCssText()
     self.ui.document:setStyleSheet(self.css, tweaks_css)
 
-    self.embedded_fonts = config:readSetting("embedded_fonts")
-    if self.embedded_fonts == nil then
+    if config:has("embedded_fonts") then
+        self.embedded_fonts = config:isTrue("embedded_fonts")
+    else
         -- default to enable embedded fonts
         -- note that it's a bit confusing here:
         -- global settins store 0/1, while document settings store false/true
@@ -42,11 +44,12 @@ function ReaderTypeset:onReadSettings(config)
         self.ui.document:setEmbeddedFonts(0)
     end
 
-    self.embedded_css = config:readSetting("embedded_css")
-    if self.embedded_css == nil then
+    if config:has("embedded_css") then
+        self.embedded_css = config:isTrue("embedded_css")
+    else
         -- default to enable embedded CSS
         -- note that it's a bit confusing here:
-        -- global settins store 0/1, while document settings store false/true
+        -- global settings store 0/1, while document settings store false/true
         -- we leave it that way for now to maintain backwards compatibility
         local global = G_reader_settings:readSetting("copt_embedded_css")
         self.embedded_css = (global == nil or global == 1) and true or false
@@ -56,15 +59,15 @@ function ReaderTypeset:onReadSettings(config)
     -- Block rendering mode: stay with legacy rendering for books
     -- previously opened so bookmarks and highlights stay valid.
     -- For new books, use 'web' mode below in BLOCK_RENDERING_FLAGS
-    local block_rendering_default_mode = 3
-    self.block_rendering_mode = config:readSetting("copt_block_rendering_mode")
-    if not self.block_rendering_mode then
-        if config:readSetting("last_xpointer") then
+    if config:has("copt_block_rendering_mode") then
+        self.block_rendering_mode = config:readSetting("copt_block_rendering_mode")
+    else
+        if config:has("last_xpointer") then
             -- We have a last_xpointer: this book was previously opened
             self.block_rendering_mode = 0
         else
             self.block_rendering_mode = G_reader_settings:readSetting("copt_block_rendering_mode")
-                                            or block_rendering_default_mode
+                                     or 3 -- default to 'web' mode
         end
         -- Let ConfigDialog know so it can update it on screen and have it saved on quit
         self.ui.document.configurable.block_rendering_mode = self.block_rendering_mode
@@ -72,47 +75,52 @@ function ReaderTypeset:onReadSettings(config)
     self:setBlockRenderingMode(self.block_rendering_mode)
 
     -- set render DPI
-    self.render_dpi = config:readSetting("render_dpi") or
-        G_reader_settings:readSetting("copt_render_dpi") or 96
+    self.render_dpi = config:readSetting("render_dpi")
+                   or G_reader_settings:readSetting("copt_render_dpi")
+                   or 96
     self:setRenderDPI(self.render_dpi)
 
     -- uncomment if we want font size to follow DPI changes
     -- self.ui.document:setRenderScaleFontWithDPI(1)
 
     -- set page margins
-    local h_margins = config:readSetting("copt_h_page_margins") or
-        G_reader_settings:readSetting("copt_h_page_margins") or
-        DCREREADER_CONFIG_H_MARGIN_SIZES_MEDIUM
-    local t_margin = config:readSetting("copt_t_page_margin") or
-        G_reader_settings:readSetting("copt_t_page_margin") or
-        DCREREADER_CONFIG_T_MARGIN_SIZES_LARGE
-    local b_margin = config:readSetting("copt_b_page_margin") or
-        G_reader_settings:readSetting("copt_b_page_margin") or
-        DCREREADER_CONFIG_B_MARGIN_SIZES_LARGE
+    local h_margins = config:readSetting("copt_h_page_margins")
+                   or G_reader_settings:readSetting("copt_h_page_margins")
+                   or DCREREADER_CONFIG_H_MARGIN_SIZES_MEDIUM
+    local t_margin = config:readSetting("copt_t_page_margin")
+                  or G_reader_settings:readSetting("copt_t_page_margin")
+                  or DCREREADER_CONFIG_T_MARGIN_SIZES_LARGE
+    local b_margin = config:readSetting("copt_b_page_margin")
+                  or G_reader_settings:readSetting("copt_b_page_margin")
+                  or DCREREADER_CONFIG_B_MARGIN_SIZES_LARGE
     self.unscaled_margins = { h_margins[1], t_margin, h_margins[2], b_margin }
     self:onSetPageMargins(self.unscaled_margins)
-    self.sync_t_b_page_margins = config:readSetting("copt_sync_t_b_page_margins") or
-        G_reader_settings:readSetting("copt_sync_t_b_page_margins") or 0
+    self.sync_t_b_page_margins = config:readSetting("copt_sync_t_b_page_margins")
+                              or G_reader_settings:readSetting("copt_sync_t_b_page_margins")
+                              or 0
     self.sync_t_b_page_margins = self.sync_t_b_page_margins == 1 and true or false
 
     -- default to disable TXT formatting as it does more harm than good
-    self.txt_preformatted = config:readSetting("txt_preformatted") or
-        G_reader_settings:readSetting("txt_preformatted") or 1
+    self.txt_preformatted = config:readSetting("txt_preformatted")
+                         or G_reader_settings:readSetting("txt_preformatted")
+                         or 1
     self:toggleTxtPreFormatted(self.txt_preformatted)
 
     -- default to disable smooth scaling for now.
-    self.smooth_scaling = config:readSetting("smooth_scaling")
-    if self.smooth_scaling == nil then
+    if config:has("smooth_scaling") then
+        self.smooth_scaling = config:isTrue("smooth_scaling")
+    else
         local global = G_reader_settings:readSetting("copt_smooth_scaling")
-        self.smooth_scaling = (global == nil or global == 0) and 0 or 1
+        self.smooth_scaling = (global == nil or global == 0) and false or true
     end
     self:toggleImageScaling(self.smooth_scaling)
 
     -- default to automagic nightmode-friendly handling of images
-    self.nightmode_images = config:readSetting("nightmode_images")
-    if self.nightmode_images == nil then
+    if config:has("nightmode_images") then
+        self.nightmode_images = config:isTrue("nightmode_images")
+    else
         local global = G_reader_settings:readSetting("copt_nightmode_images")
-        self.nightmode_images = (global == nil or global == 1) and 1 or 0
+        self.nightmode_images = (global == nil or global == 1) and true or false
     end
     self:toggleNightmodeImages(self.nightmode_images)
 end

frontend/apps/reader/modules/readertypography.lua

@@ -126,7 +126,7 @@ function ReaderTypography:init()
 
     -- Migrate old readerhyphenation settings (but keep them in case one
     -- go back to a previous version)
-    if not G_reader_settings:readSetting("text_lang_default") and not G_reader_settings:readSetting("text_lang_fallback") then
+    if G_reader_settings:hasNot("text_lang_default") and G_reader_settings:hasNot("text_lang_fallback") then
         local g_text_lang_set = false
         local hyph_alg_default = G_reader_settings:readSetting("hyph_alg_default")
         if hyph_alg_default then
@@ -137,11 +137,11 @@ function ReaderTypography:init()
                 -- Tweak the other settings if the default hyph algo happens
                 -- to be one of these:
                 if hyph_alg_default == "@none" then
-                    G_reader_settings:saveSetting("hyphenation", false)
+                    G_reader_settings:makeFalse("hyphenation")
                 elseif hyph_alg_default == "@softhyphens" then
-                    G_reader_settings:saveSetting("hyph_soft_hyphens_only", true)
+                    G_reader_settings:makeTrue("hyph_soft_hyphens_only")
                 elseif hyph_alg_default == "@algorithm" then
-                    G_reader_settings:saveSetting("hyph_force_algorithmic", true)
+                    G_reader_settings:makeTrue("hyph_force_algorithmic")
                 end
             end
         end
@@ -328,13 +328,13 @@ When the book's language tag is not among our presets, no specific features will
                     return text_lang_embedded_langs and _("Ignore") or _("Ignore (★)")
                 end,
                 choice1_callback = function()
-                    G_reader_settings:saveSetting("text_lang_embedded_langs", false)
+                    G_reader_settings:makeFalse("text_lang_embedded_langs")
                 end,
                 choice2_text_func = function()
                     return text_lang_embedded_langs and _("Respect (★)") or _("Respect")
                 end,
                 choice2_callback = function()
-                    G_reader_settings:saveSetting("text_lang_embedded_langs", true)
+                    G_reader_settings:makeTrue("text_lang_embedded_langs")
                 end,
             })
         end,
@@ -361,13 +361,13 @@ When the book's language tag is not among our presets, no specific features will
                     return hyphenation and _("Disable") or _("Disable (★)")
                 end,
                 choice1_callback = function()
-                    G_reader_settings:saveSetting("hyphenation", false)
+                    G_reader_settings:makeFalse("hyphenation")
                 end,
                 choice2_text_func = function()
                     return hyphenation and _("Enable (★)") or _("Enable")
                 end,
                 choice2_callback = function()
-                    G_reader_settings:saveSetting("hyphenation", true)
+                    G_reader_settings:makeTrue("hyphenation")
                 end,
             })
         end,
@@ -379,8 +379,8 @@ When the book's language tag is not among our presets, no specific features will
         text_func = function()
             -- Note: with our callback, we either get hyph_left_hyphen_min and
             -- hyph_right_hyphen_min both nil, or both defined.
-            if G_reader_settings:readSetting("hyph_left_hyphen_min") or
-                        G_reader_settings:readSetting("hyph_right_hyphen_min") then
+            if G_reader_settings:has("hyph_left_hyphen_min") or
+                        G_reader_settings:has("hyph_right_hyphen_min") then
                 -- @translators to RTL language translators: %1/left is the min length of the start of a hyphenated word, %2/right is the min length of the end of a hyphenated word (note that there is yet no support for hyphenation with RTL languages, so this will mostly apply to LTR documents)
                 return T(_("Left/right minimal sizes: %1 - %2"),
                     G_reader_settings:readSetting("hyph_left_hyphen_min"),
@@ -447,13 +447,13 @@ These settings will apply to all books with any hyphenation dictionary.
                     return hyph_trust_soft_hyphens and _("Disable") or _("Disable (★)")
                 end,
                 choice1_callback = function()
-                    G_reader_settings:saveSetting("hyph_trust_soft_hyphens", false)
+                    G_reader_settings:makeFalse("hyph_trust_soft_hyphens")
                 end,
                 choice2_text_func = function()
                     return hyph_trust_soft_hyphens and _("Enable (★)") or _("Enable")
                 end,
                 choice2_callback = function()
-                    G_reader_settings:saveSetting("hyph_trust_soft_hyphens", true)
+                    G_reader_settings:makeTrue("hyph_trust_soft_hyphens")
                 end,
             })
         end,
@@ -504,13 +504,13 @@ These settings will apply to all books with any hyphenation dictionary.
                     return hyph_force_algorithmic and _("Disable") or _("Disable (★)")
                 end,
                 choice1_callback = function()
-                    G_reader_settings:saveSetting("hyph_force_algorithmic", false)
+                    G_reader_settings:makeFalse("hyph_force_algorithmic")
                 end,
                 choice2_text_func = function()
                     return hyph_force_algorithmic and _("Enable (★)") or _("Enable")
                 end,
                 choice2_callback = function()
-                    G_reader_settings:saveSetting("hyph_force_algorithmic", true)
+                    G_reader_settings:makeTrue("hyph_force_algorithmic")
                 end,
             })
         end,
@@ -541,13 +541,13 @@ These settings will apply to all books with any hyphenation dictionary.
                     return hyph_soft_hyphens_only and _("Disable") or _("Disable (★)")
                 end,
                 choice1_callback = function()
-                    G_reader_settings:saveSetting("hyph_soft_hyphens_only", false)
+                    G_reader_settings:makeFalse("hyph_soft_hyphens_only")
                 end,
                 choice2_text_func = function()
                     return hyph_soft_hyphens_only and _("Enable (★)") or _("Enable")
                 end,
                 choice2_callback = function()
-                    G_reader_settings:saveSetting("hyph_soft_hyphens_only", true)
+                    G_reader_settings:makeTrue("hyph_soft_hyphens_only")
                 end,
             })
         end,
@@ -625,13 +625,13 @@ function ReaderTypography:makeDefaultFloatingPunctuation()
             return floating_punctuation and _("Disable") or _("Disable (★)")
         end,
         choice1_callback = function()
-            G_reader_settings:saveSetting("floating_punctuation", false)
+            G_reader_settings:makeFalse("floating_punctuation")
         end,
         choice2_text_func = function()
             return floating_punctuation and _("Enable (★)") or _("Enable")
         end,
         choice2_callback = function()
-            G_reader_settings:saveSetting("floating_punctuation", true)
+            G_reader_settings:makeTrue("floating_punctuation")
         end,
     })
 end
@@ -701,7 +701,7 @@ end
 -- in book settings, no default lang, and book has some language defined.
 function ReaderTypography:onReadSettings(config)
     -- Migrate old readerhyphenation setting, if one was set
-    if not config:readSetting("text_lang") and config:readSetting("hyph_alg") then
+    if config:hasNot("text_lang") and config:has("hyph_alg") then
         local hyph_alg = config:readSetting("hyph_alg")
         local dict_info = HYPH_DICT_NAME_TO_LANG_NAME_TAG[hyph_alg]
         if dict_info then
@@ -709,46 +709,51 @@ function ReaderTypography:onReadSettings(config)
             -- Set the other settings if the default hyph algo happens
             -- to be one of these:
             if hyph_alg == "@none" then
-                config:saveSetting("hyphenation", false)
+                config:makeFalse("hyphenation")
             elseif hyph_alg == "@softhyphens" then
-                config:saveSetting("hyph_soft_hyphens_only", true)
+                config:makeTrue("hyph_soft_hyphens_only")
             elseif hyph_alg == "@algorithm" then
-                config:saveSetting("hyph_force_algorithmic", true)
+                config:makeTrue("hyph_force_algorithmic")
             end
         end
     end
 
     -- Enable text lang tags attributes by default
-    self.text_lang_embedded_langs = config:readSetting("text_lang_embedded_langs")
-    if self.text_lang_embedded_langs == nil then
+    if config:has("text_lang_embedded_langs") then
+        self.text_lang_embedded_langs = config:isTrue("text_lang_embedded_langs")
+    else
         self.text_lang_embedded_langs = G_reader_settings:nilOrTrue("text_lang_embedded_langs")
     end
     self.ui.document:setTextEmbeddedLangs(self.text_lang_embedded_langs)
 
     -- Enable hyphenation by default
-    self.hyphenation = config:readSetting("hyphenation")
-    if self.hyphenation == nil then
+    if config:has("hyphenation") then
+        self.hyphenation = config:isTrue("hyphenation")
+    else
         self.hyphenation = G_reader_settings:nilOrTrue("hyphenation")
     end
     self.ui.document:setTextHyphenation(self.hyphenation)
 
     -- Checking for soft-hyphens adds a bit of overhead, so have it disabled by default
-    self.hyph_trust_soft_hyphens = config:readSetting("hyph_trust_soft_hyphens")
-    if self.hyph_trust_soft_hyphens == nil then
+    if config:has("hyph_trust_soft_hyphens") then
+        self.hyph_trust_soft_hyphens = config:isTrue("hyph_trust_soft_hyphens")
+    else
         self.hyph_trust_soft_hyphens = G_reader_settings:isTrue("hyph_trust_soft_hyphens")
     end
     self.ui.document:setTrustSoftHyphens(self.hyph_trust_soft_hyphens)
 
     -- Alternative hyphenation method (available with all dicts) to use soft hyphens only
-    self.hyph_soft_hyphens_only = config:readSetting("hyph_soft_hyphens_only")
-    if self.hyph_soft_hyphens_only == nil then
+    if config:has("hyph_soft_hyphens_only") then
+        self.hyph_soft_hyphens_only = config:isTrue("hyph_soft_hyphens_only")
+    else
         self.hyph_soft_hyphens_only = G_reader_settings:isTrue("hyph_soft_hyphens_only")
     end
     self.ui.document:setTextHyphenationSoftHyphensOnly(self.hyph_soft_hyphens_only)
 
     -- Alternative hyphenation method (available with all dicts) to use algorithmic hyphenation
-    self.hyph_force_algorithmic = config:readSetting("hyph_force_algorithmic")
-    if self.hyph_force_algorithmic == nil then
+    if config:has("hyph_force_algorithmic") then
+        self.hyph_force_algorithmic = config:isTrue("hyph_force_algorithmic")
+    else
         self.hyph_force_algorithmic = G_reader_settings:isTrue("hyph_force_algorithmic")
     end
     self.ui.document:setTextHyphenationForceAlgorithmic(self.hyph_force_algorithmic)
@@ -760,40 +765,36 @@ function ReaderTypography:onReadSettings(config)
     -- Default to disable hanging/floating punctuation
     -- (Stored as 0/1 in docsetting for historical reasons, but as true/false
     -- in global settings.)
-    self.floating_punctuation = config:readSetting("floating_punctuation")
-    if self.floating_punctuation == nil then
+    if config:has("floating_punctuation") then
+        self.floating_punctuation = config:readSetting("floating_punctuation")
+    else
         self.floating_punctuation = G_reader_settings:isTrue("floating_punctuation") and 1 or 0
     end
     self:onToggleFloatingPunctuation(self.floating_punctuation)
 
     -- Decide and set the text main lang tag according to settings
-    self.allow_doc_lang_tag_override = false
-    -- Use the one manually set for this document
-    self.text_lang_tag = config:readSetting("text_lang")
-    if self.text_lang_tag then
+    if config:has("text_lang") then
+        self.allow_doc_lang_tag_override = false
+        -- Use the one manually set for this document
+        self.text_lang_tag = config:readSetting("text_lang")
         logger.dbg("Typography lang: using", self.text_lang_tag, "from doc settings")
-        self.ui.document:setTextMainLang(self.text_lang_tag)
-        return
-    end
-    -- Use the one manually set as default (with Hold)
-    self.text_lang_tag = G_reader_settings:readSetting("text_lang_default")
-    if self.text_lang_tag then
+    elseif G_reader_settings:has("text_lang_default") then
+        self.allow_doc_lang_tag_override = false
+        -- Use the one manually set as default (with Hold)
+        self.text_lang_tag = G_reader_settings:readSetting("text_lang_default")
         logger.dbg("Typography lang: using default ", self.text_lang_tag)
-        self.ui.document:setTextMainLang(self.text_lang_tag)
-        return
-    end
-    -- Document language will be allowed to override the one we set from now on
-    self.allow_doc_lang_tag_override = true
-    -- Use the one manually set as fallback (with Hold)
-    self.text_lang_tag = G_reader_settings:readSetting("text_lang_fallback")
-    if self.text_lang_tag then
+    elseif G_reader_settings:has("text_lang_fallback") then
+        -- Document language will be allowed to override the one we set from now on
+        self.allow_doc_lang_tag_override = true
+        -- Use the one manually set as fallback (with Hold)
+        self.text_lang_tag = G_reader_settings:readSetting("text_lang_fallback")
         logger.dbg("Typography lang: using fallback ", self.text_lang_tag, ", might be overriden by doc language")
-        self.ui.document:setTextMainLang(self.text_lang_tag)
-        return
+    else
+        self.allow_doc_lang_tag_override = true
+        -- None decided, use default (shouldn't be reached)
+        self.text_lang_tag = DEFAULT_LANG_TAG
+        logger.dbg("Typography lang: no lang set, using", self.text_lang_tag)
     end
-    -- None decided, use default (shouldn't be reached)
-    self.text_lang_tag = DEFAULT_LANG_TAG
-    logger.dbg("Typography lang: no lang set, using", self.text_lang_tag)
     self.ui.document:setTextMainLang(self.text_lang_tag)
 end
 

frontend/apps/reader/modules/readerview.lua

@@ -33,7 +33,7 @@ local ReaderView = OverlapGroup:extend{
         offset = nil,
         bbox = nil,
     },
-    outer_page_color = Blitbuffer.gray(DOUTER_PAGE_COLOR/15),
+    outer_page_color = Blitbuffer.gray(DOUTER_PAGE_COLOR / 15),
     -- highlight with "lighten" or "underscore" or "invert"
     highlight = {
         lighten_factor = 0.2,
@@ -45,12 +45,12 @@ local ReaderView = OverlapGroup:extend{
     highlight_visible = true,
     -- PDF/DjVu continuous paging
     page_scroll = nil,
-    page_bgcolor = Blitbuffer.gray(DBACKGROUND_COLOR/15),
+    page_bgcolor = Blitbuffer.gray(DBACKGROUND_COLOR / 15),
     page_states = {},
     -- properties of the gap drawn between each page in scroll mode:
     page_gap = {
         -- color (0 = white, 8 = gray, 15 = black)
-        color = Blitbuffer.gray((G_reader_settings:readSetting("page_gap_color") or 8)/15),
+        color = Blitbuffer.gray((G_reader_settings:readSetting("page_gap_color") or 8) / 15),
     },
     -- DjVu page rendering mode (used in djvu.c:drawPage())
     render_mode = DRENDER_MODE, -- default to COLOR
@@ -758,8 +758,9 @@ function ReaderView:onReadSettings(config)
     -- Keep current rotation by doing nothing when sticky rota is enabled.
     if not locked then
         -- Honor docsettings's rotation
-        rotation_mode = config:readSetting("rotation_mode") -- Doc's
-        if not rotation_mode then
+        if config:has("rotation_mode") then
+            rotation_mode = config:readSetting("rotation_mode") -- Doc's
+        else
             -- No doc specific rotation, pickup global defaults for the doc type
             if self.ui.document.info.has_pages then
                 rotation_mode = G_reader_settings:readSetting("kopt_rotation_mode") or Screen.ORIENTATION_PORTRAIT
@@ -781,8 +782,9 @@ function ReaderView:onReadSettings(config)
     self.page_scroll = page_scroll == 1 and true or false
     self.highlight.saved = config:readSetting("highlight") or {}
     self.page_overlap_style = config:readSetting("page_overlap_style") or G_reader_settings:readSetting("page_overlap_style") or "dim"
-    self.page_gap.height = Screen:scaleBySize(config:readSetting("kopt_page_gap_height") or
-        G_reader_settings:readSetting("kopt_page_gap_height") or 8)
+    self.page_gap.height = Screen:scaleBySize(config:readSetting("kopt_page_gap_height")
+                                              or G_reader_settings:readSetting("kopt_page_gap_height")
+                                              or 8)
 end
 
 function ReaderView:onPageUpdate(new_page_no)
@@ -965,11 +967,12 @@ function ReaderView:checkAutoSaveSettings()
     if not self.settings_last_save_ts then -- reader not yet ready
         return
     end
-    local interval = G_reader_settings:readSetting("auto_save_settings_interval_minutes")
-    if not interval then -- no auto save
+    if G_reader_settings:nilOrFalse("auto_save_settings_interval_minutes") then
+        -- no auto save
         return
     end
 
+    local interval = G_reader_settings:readSetting("auto_save_settings_interval_minutes")
     local now_ts = os.time()
     if now_ts - self.settings_last_save_ts >= interval*60 then
         self.settings_last_save_ts = now_ts

frontend/apps/reader/modules/readerwikipedia.lua

@@ -175,8 +175,8 @@ function ReaderWikipedia:addToMainMenu(menu_items)
                     local choose_directory = function()
                         -- Default directory as chosen by DictQuickLookup
                         local default_dir = G_reader_settings:readSetting("wikipedia_save_dir")
-                        if not default_dir then default_dir = G_reader_settings:readSetting("home_dir") end
-                        if not default_dir then default_dir = require("apps/filemanager/filemanagerutil").getDefaultDir() end
+                                         or G_reader_settings:readSetting("home_dir")
+                                         or require("apps/filemanager/filemanagerutil").getDefaultDir()
                         local dialog
                         dialog = ButtonDialogTitle:new{
                             title = T(_("Current Wikipedia 'Save as EPUB' folder:\n\n%1\n"), BD.dirpath(default_dir)),
@@ -198,9 +198,9 @@ function ReaderWikipedia:addToMainMenu(menu_items)
                                         -- so a user reading a wikipedia article can quickly select
                                         -- it to save related new articles in the same directory
                                         local dir = G_reader_settings:readSetting("wikipedia_save_dir")
-                                        if not dir then dir = G_reader_settings:readSetting("home_dir") end
-                                        if not dir then dir = require("apps/filemanager/filemanagerutil").getDefaultDir() end
-                                        if not dir then dir = "/" end
+                                                 or G_reader_settings:readSetting("home_dir")
+                                                 or require("apps/filemanager/filemanagerutil").getDefaultDir()
+                                                 or "/"
                                         -- If this directory has no subdirectory, we would be displaying
                                         -- a single "..", so use parent directory in that case.
                                         local has_subdirectory = false

frontend/apps/reader/modules/readerzooming.lua

@@ -114,13 +114,13 @@ function ReaderZooming:onReadSettings(config)
                     or G_reader_settings:readSetting("zoom_mode")
                     or self.DEFAULT_ZOOM_MODE
     zoom_mode = util.arrayContains(self.available_zoom_modes, zoom_mode)
-                                and zoom_mode
-                                or self.DEFAULT_ZOOM_MODE
+            and zoom_mode
+             or self.DEFAULT_ZOOM_MODE
     self:setZoomMode(zoom_mode, true) -- avoid informative message on load
     for _, setting in ipairs(self.zoom_pan_settings) do
-        self[setting] = config:readSetting(setting) or
-                    G_reader_settings:readSetting(setting) or
-                    self[setting]
+        self[setting] = config:readSetting(setting)
+                     or G_reader_settings:readSetting(setting)
+                     or self[setting]
     end
 end
 
@@ -433,8 +433,8 @@ function ReaderZooming:getZoom(pageno)
         zoom = self.zoom
     else
         local zoom_factor = self.ui.doc_settings:readSetting("zoom_factor")
-                            or G_reader_settings:readSetting("zoom_factor")
-                            or self.zoom_factor
+                         or G_reader_settings:readSetting("zoom_factor")
+                         or self.zoom_factor
         zoom = zoom_w * zoom_factor
     end
     if zoom and zoom > 10 and not Cache:willAccept(zoom * (self.dimen.w * self.dimen.h + 64)) then

frontend/apps/reader/readerui.lua

@@ -332,7 +332,7 @@ function ReaderUI:init()
             ui = self
         })
     end
-    self.disable_double_tap = G_reader_settings:readSetting("disable_double_tap") ~= false
+    self.disable_double_tap = G_reader_settings:nilOrTrue("disable_double_tap")
     -- back location stack
     self:registerModule("back", ReaderBack:new{
         ui = self,

frontend/device/cervantes/device.lua

@@ -204,6 +204,7 @@ end
 function Cervantes:intoScreenSaver()
     local Screensaver = require("ui/screensaver")
     if self.screen_saver_mode == false then
+        Screensaver:setup()
         Screensaver:show()
     end
     self.powerd:beforeSuspend()

frontend/device/devicelistener.lua

@@ -12,7 +12,7 @@ local T = require("ffi/util").template
 local DeviceListener = InputContainer:new{}
 
 local function _setSetting(name)
-    G_reader_settings:saveSetting(name, true)
+    G_reader_settings:makeTrue(name)
 end
 
 local function _unsetSetting(name)

frontend/device/generic/device.lua

@@ -168,9 +168,8 @@ function Device:init()
 
     self.screen.isBGRFrameBuffer = self.hasBGRFrameBuffer
 
-    local low_pan_rate = G_reader_settings:readSetting("low_pan_rate")
-    if low_pan_rate ~= nil then
-        self.screen.low_pan_rate = low_pan_rate
+    if G_reader_settings:has("low_pan_rate") then
+        self.screen.low_pan_rate = G_reader_settings:readSetting("low_pan_rate")
     else
         self.screen.low_pan_rate = self.hasEinkScreen()
     end
@@ -226,6 +225,7 @@ end
 
 -- Only used on platforms where we handle suspend ourselves.
 function Device:onPowerEvent(ev)
+    local Screensaver = require("ui/screensaver")
     if self.screen_saver_mode then
         if ev == "Power" or ev == "Resume" then
             if self.is_cover_closed then
@@ -247,7 +247,7 @@ function Device:onPowerEvent(ev)
                 if self.orig_rotation_mode then
                     self.screen:setRotationMode(self.orig_rotation_mode)
                 end
-                require("ui/screensaver"):close()
+                Screensaver:close()
                 if self:needsScreenRefreshAfterResume() then
                     UIManager:scheduleIn(1, function() self.screen:refreshFull() end)
                 end
@@ -266,14 +266,14 @@ function Device:onPowerEvent(ev)
         self.powerd:beforeSuspend()
         local UIManager = require("ui/uimanager")
         logger.dbg("Suspending...")
+        -- Let Screensaver set its widget up, so we get accurate info down the line in case fallbacks kick in...
+        Screensaver:setup()
         -- Mostly always suspend in Portrait/Inverted Portrait mode...
         -- ... except when we just show an InfoMessage or when the screensaver
         -- is disabled, as it plays badly with Landscape mode (c.f., #4098 and #5290).
         -- We also exclude full-screen widgets that work fine in Landscape mode,
         -- like ReadingProgress and BookStatus (c.f., #5724)
-        local screensaver_type = G_reader_settings:readSetting("screensaver_type")
-        if screensaver_type ~= "message" and screensaver_type ~= "disable" and
-           screensaver_type ~= "readingprogress" and screensaver_type ~= "bookstatus" then
+        if Screensaver:modeExpectsPortrait() then
             self.orig_rotation_mode = self.screen:getRotationMode()
             -- Leave Portrait & Inverted Portrait alone, that works just fine.
             if bit.band(self.orig_rotation_mode, 1) == 1 then
@@ -285,10 +285,8 @@ function Device:onPowerEvent(ev)
 
             -- On eInk, if we're using a screensaver mode that shows an image,
             -- flash the screen to white first, to eliminate ghosting.
-            if self:hasEinkScreen() and
-               screensaver_type == "cover" or screensaver_type == "random_image" or
-               screensaver_type == "image_file" then
-                if not G_reader_settings:isTrue("screensaver_no_background") then
+            if self:hasEinkScreen() and Screensaver:modeIsImage() then
+                if Screensaver:withBackground() then
                     self.screen:clear()
                 end
                 self.screen:refreshFull()
@@ -297,7 +295,7 @@ function Device:onPowerEvent(ev)
             -- nil it, in case user switched ScreenSaver modes during our lifetime.
             self.orig_rotation_mode = nil
         end
-        require("ui/screensaver"):show()
+        Screensaver:show()
         -- NOTE: show() will return well before the refresh ioctl is even *sent*:
         --       the only thing it's done is *enqueued* the refresh in UIManager's stack.
         --       Which is why the actual suspension needs to be delayed by suspend_wait_timeout,

frontend/device/kindle/device.lua

@@ -178,14 +178,14 @@ function Kindle:intoScreenSaver()
             -- NOTE: Meaning this is not a SO device ;)
             local Screensaver = require("ui/screensaver")
             -- NOTE: Pilefered from Device:onPowerEvent @ frontend/device/generic/device.lua
+            -- Let Screensaver set its widget up, so we get accurate info down the line in case fallbacks kick in...
+            Screensaver:setup()
             -- Mostly always suspend in Portrait/Inverted Portrait mode...
             -- ... except when we just show an InfoMessage or when the screensaver
             -- is disabled, as it plays badly with Landscape mode (c.f., #4098 and #5290).
             -- We also exclude full-screen widgets that work fine in Landscape mode,
             -- like ReadingProgress and BookStatus (c.f., #5724)
-            local screensaver_type = G_reader_settings:readSetting("screensaver_type")
-            if screensaver_type ~= "message" and screensaver_type ~= "disable" and
-               screensaver_type ~= "readingprogress" and screensaver_type ~= "bookstatus" then
+            if Screensaver:modeExpectsPortrait() then
                 self.orig_rotation_mode = self.screen:getRotationMode()
                 -- Leave Portrait & Inverted Portrait alone, that works just fine.
                 if bit.band(self.orig_rotation_mode, 1) == 1 then
@@ -197,10 +197,8 @@ function Kindle:intoScreenSaver()
 
                 -- On eInk, if we're using a screensaver mode that shows an image,
                 -- flash the screen to white first, to eliminate ghosting.
-                if self:hasEinkScreen() and
-                   screensaver_type == "cover" or screensaver_type == "random_image" or
-                   screensaver_type == "image_file" then
-                    if not G_reader_settings:isTrue("screensaver_no_background") then
+                if self:hasEinkScreen() and Screensaver:modeIsImage() then
+                    if Screensaver:withBackground() then
                         self.screen:clear()
                     end
                     self.screen:refreshFull()

frontend/device/kobo/device.lua

@@ -340,17 +340,15 @@ function Kobo:init()
         self.touchScreenProbe = function()
             -- if user has not set KOBO_TOUCH_MIRRORED yet
             if KOBO_TOUCH_MIRRORED == nil then
-                local switch_xy = G_reader_settings:readSetting("kobo_touch_switch_xy")
                 -- and has no probe before
-                if switch_xy == nil then
+                if G_reader_settings:hasNot("kobo_touch_switch_xy") then
                     local TouchProbe = require("tools/kobo_touch_probe")
                     local UIManager = require("ui/uimanager")
                     UIManager:show(TouchProbe:new{})
                     UIManager:run()
                     -- assuming TouchProbe sets kobo_touch_switch_xy config
-                    switch_xy = G_reader_settings:readSetting("kobo_touch_switch_xy")
                 end
-                self.touch_switch_xy = switch_xy
+                self.touch_switch_xy = G_reader_settings:readSetting("kobo_touch_switch_xy")
             end
             self:initEventAdjustHooks()
         end

frontend/device/sdl/device.lua

@@ -90,7 +90,7 @@ local Device = Generic:new{
             external.when_back_callback = nil
         end
     end,
-    window = G_reader_settings:readSetting("sdl_window") or {},
+    window = G_reader_settings:readSetting("sdl_window", {}),
 }
 
 local AppImage = Device:new{
@@ -323,12 +323,6 @@ function Device:setDateTime(year, month, day, hour, min, sec)
     end
 end
 
-function Device:exit()
-    G_reader_settings:saveSetting("sdl_window", self.window)
-    G_reader_settings:flush()
-    Generic.exit(self)
-end
-
 function Emulator:simulateSuspend()
     local InfoMessage = require("ui/widget/infomessage")
     local UIManager = require("ui/uimanager")

frontend/device/sony-prstux/device.lua

@@ -94,6 +94,7 @@ end
 function SonyPRSTUX:intoScreenSaver()
     local Screensaver = require("ui/screensaver")
     if self.screen_saver_mode == false then
+        Screensaver:setup()
         Screensaver:show()
     end
     self.powerd:beforeSuspend()

frontend/docsettings.lua

@@ -165,19 +165,136 @@ function DocSettings:open(docfile)
     return setmetatable(new, {__index = DocSettings})
 end
 
---- Reads a setting.
-function DocSettings:readSetting(key)
+--[[-- Reads a setting, optionally initializing it to a default.
+
+If default is provided, and the key doesn't exist yet, it is initialized to default first.
+This ensures both that the defaults are actually set if necessary,
+and that the returned reference actually belongs to the DocSettings object straight away,
+without requiring further interaction (e.g., saveSetting) from the caller.
+
+This is mainly useful if the data type you want to retrieve/store is assigned/returned/passed by reference (e.g., a table),
+and you never actually break that reference by assigning another one to the same variable, (by e.g., assigning it a new object).
+c.f., https://www.lua.org/manual/5.1/manual.html#2.2
+
+@param key The setting's key
+@param default Initialization data (Optional)
+]]
+function DocSettings:readSetting(key, default)
+    -- No initialization data: legacy behavior
+    if not default then
+        return self.data[key]
+    end
+
+    if not self:has(key) then
+        self.data[key] = default
+    end
     return self.data[key]
 end
 
 --- Saves a setting.
 function DocSettings:saveSetting(key, value)
     self.data[key] = value
+    return self
 end
 
 --- Deletes a setting.
 function DocSettings:delSetting(key)
     self.data[key] = nil
+    return self
+end
+
+--- Checks if setting exists.
+function DocSettings:has(key)
+    return self.data[key] ~= nil
+end
+
+--- Checks if setting does not exist.
+function DocSettings:hasNot(key)
+    return self.data[key] == nil
+end
+
+--- Checks if setting is `true` (boolean).
+function DocSettings:isTrue(key)
+    return self.data[key] == true
+end
+
+--- Checks if setting is `false` (boolean).
+function DocSettings:isFalse(key)
+    return self.data[key] == false
+end
+
+--- Checks if setting is `nil` or `true`.
+function DocSettings:nilOrTrue(key)
+    return self:hasNot(key) or self:isTrue(key)
+end
+
+--- Checks if setting is `nil` or `false`.
+function DocSettings:nilOrFalse(key)
+    return self:hasNot(key) or self:isFalse(key)
+end
+
+--- Flips `nil` or `true` to `false`, and `false` to `nil`.
+--- e.g., a setting that defaults to true.
+function DocSettings:flipNilOrTrue(key)
+    if self:nilOrTrue(key) then
+        self:saveSetting(key, false)
+    else
+        self:delSetting(key)
+    end
+    return self
+end
+
+--- Flips `nil` or `false` to `true`, and `true` to `nil`.
+--- e.g., a setting that defaults to false.
+function DocSettings:flipNilOrFalse(key)
+    if self:nilOrFalse(key) then
+        self:saveSetting(key, true)
+    else
+        self:delSetting(key)
+    end
+    return self
+end
+
+--- Flips a setting between `true` and `nil`.
+function DocSettings:flipTrue(key)
+    if self:isTrue(key) then
+        self:delSetting(key)
+    else
+        self:saveSetting(key, true)
+    end
+    return self
+end
+
+--- Flips a setting between `false` and `nil`.
+function DocSettings:flipFalse(key)
+    if self:isFalse(key) then
+        self:delSetting(key)
+    else
+        self:saveSetting(key, false)
+    end
+    return self
+end
+
+-- Unconditionally makes a boolean setting `true`.
+function DocSettings:makeTrue(key)
+    self:saveSetting(key, true)
+    return self
+end
+
+-- Unconditionally makes a boolean setting `false`.
+function DocSettings:makeFalse(key)
+    self:saveSetting(key, false)
+    return self
+end
+
+--- Toggles a boolean setting
+function DocSettings:toggle(key)
+    if self:nilOrFalse(key) then
+        self:saveSetting(key, true)
+    else
+        self:saveSetting(key, false)
+    end
+    return self
 end
 
 --- Serializes settings and writes them to `metadata.lua`.
@@ -220,8 +337,7 @@ function DocSettings:flush()
             f_out:close()
 
             if self.candidates ~= nil
-            and not G_reader_settings:readSetting(
-                        "preserve_legacy_docsetting") then
+            and G_reader_settings:nilOrFalse("preserve_legacy_docsetting") then
                 for _, k in pairs(self.candidates) do
                     if k[1] ~= f and k[1] ~= f .. ".old" then
                         logger.dbg("Remove legacy file ", k[1])

frontend/document/credocument.lua

@@ -228,16 +228,16 @@ function CreDocument:setupDefaultView()
     self._document:adjustFontSizes(CanvasContext:getDPI())
 
     -- set top status bar font size
-    if G_reader_settings:readSetting("cre_header_status_font_size") then
+    if G_reader_settings:has("cre_header_status_font_size") then
         self._document:setIntProperty("crengine.page.header.font.size",
             G_reader_settings:readSetting("cre_header_status_font_size"))
     end
 
     -- One can set these to change from white background
-    if G_reader_settings:readSetting("cre_background_color") then
+    if G_reader_settings:has("cre_background_color") then
         self:setBackgroundColor(G_reader_settings:readSetting("cre_background_color"))
     end
-    if G_reader_settings:readSetting("cre_background_image") then
+    if G_reader_settings:has("cre_background_image") then
         self:setBackgroundImage(G_reader_settings:readSetting("cre_background_image"))
     end
 end

frontend/document/documentregistry.lua

@@ -72,10 +72,7 @@ function DocumentRegistry:hasProvider(file, mimetype)
     end
     local DocSettings = require("docsettings")
     if DocSettings:hasSidecarFile(file) then
-        local doc_settings_provider = DocSettings:open(file):readSetting("provider")
-        if doc_settings_provider then
-            return true
-        end
+        return DocSettings:open(file):has("provider")
     end
     return false
 end
@@ -134,7 +131,8 @@ function DocumentRegistry:getProviders(file)
         local added = false
         local suffix = string.sub(file, -string.len(provider.extension) - 1)
         if string.lower(suffix) == "."..provider.extension then
-            for i, prov_prev in ipairs(providers) do
+            for i = #providers, 1, -1 do
+                local prov_prev = providers[i]
                 if prov_prev.provider == provider.provider then
                     if prov_prev.weight >= provider.weight then
                         added = true
@@ -143,7 +141,7 @@ function DocumentRegistry:getProviders(file)
                     end
                 end
             end
-        -- if extension == provider.extension then
+            -- if extension == provider.extension then
             -- stick highest weighted provider at the front
             if not added and #providers >= 1 and provider.weight > providers[1].weight then
                 table.insert(providers, 1, provider)

frontend/luasettings.lua

@@ -56,7 +56,7 @@ end
 
     Settings:saveSetting("key", {
         a = "b",
-        c = "true",
+        c = true,
         d = false,
     })
 
@@ -69,8 +69,29 @@ function LuaSettings:child(key)
     return LuaSettings:wrap(self:readSetting(key))
 end
 
---- Reads a setting.
-function LuaSettings:readSetting(key)
+--[[-- Reads a setting, optionally initializing it to a default.
+
+If default is provided, and the key doesn't exist yet, it is initialized to default first.
+This ensures both that the defaults are actually set if necessary,
+and that the returned reference actually belongs to the LuaSettings object straight away,
+without requiring further interaction (e.g., saveSetting) from the caller.
+
+This is mainly useful if the data type you want to retrieve/store is assigned/returned/passed by reference (e.g., a table),
+and you never actually break that reference by assigning another one to the same variable, (by e.g., assigning it a new object).
+c.f., <https://www.lua.org/manual/5.1/manual.html#2.2>.
+
+@param key The setting's key
+@param default Initialization data (Optional)
+]]
+function LuaSettings:readSetting(key, default)
+    -- No initialization data: legacy behavior
+    if not default then
+        return self.data[key]
+    end
+
+    if not self:has(key) then
+        self.data[key] = default
+    end
     return self.data[key]
 end
 
@@ -88,22 +109,22 @@ end
 
 --- Checks if setting exists.
 function LuaSettings:has(key)
-    return self:readSetting(key) ~= nil
+    return self.data[key] ~= nil
 end
 
 --- Checks if setting does not exist.
 function LuaSettings:hasNot(key)
-    return self:readSetting(key) == nil
+    return self.data[key] == nil
 end
 
---- Checks if setting is `true`.
+--- Checks if setting is `true` (boolean).
 function LuaSettings:isTrue(key)
-    return string.lower(tostring(self:readSetting(key))) == "true"
+    return self.data[key] == true
 end
 
---- Checks if setting is `false`.
+--- Checks if setting is `false` (boolean).
 function LuaSettings:isFalse(key)
-    return string.lower(tostring(self:readSetting(key))) == "false"
+    return self.data[key] == false
 end
 
 --- Checks if setting is `nil` or `true`.
@@ -116,7 +137,8 @@ function LuaSettings:nilOrFalse(key)
     return self:hasNot(key) or self:isFalse(key)
 end
 
---- Flips `nil` or `true` to `false`.
+--- Flips `nil` or `true` to `false`, and `false` to `nil`.
+--- e.g., a setting that defaults to true.
 function LuaSettings:flipNilOrTrue(key)
     if self:nilOrTrue(key) then
         self:saveSetting(key, false)
@@ -126,7 +148,8 @@ function LuaSettings:flipNilOrTrue(key)
     return self
 end
 
---- Flips `nil` or `false` to `true`.
+--- Flips `nil` or `false` to `true`, and `true` to `nil`.
+--- e.g., a setting that defaults to false.
 function LuaSettings:flipNilOrFalse(key)
     if self:nilOrFalse(key) then
         self:saveSetting(key, true)
@@ -136,7 +159,7 @@ function LuaSettings:flipNilOrFalse(key)
     return self
 end
 
---- Flips setting to `true`.
+--- Flips a setting between `true` and `nil`.
 function LuaSettings:flipTrue(key)
     if self:isTrue(key) then
         self:delSetting(key)
@@ -146,7 +169,7 @@ function LuaSettings:flipTrue(key)
     return self
 end
 
---- Flips setting to `false`.
+--- Flips a setting between `false` and `nil`.
 function LuaSettings:flipFalse(key)
     if self:isFalse(key) then
         self:delSetting(key)
@@ -156,6 +179,28 @@ function LuaSettings:flipFalse(key)
     return self
 end
 
+-- Unconditionally makes a boolean setting `true`.
+function LuaSettings:makeTrue(key)
+    self:saveSetting(key, true)
+    return self
+end
+
+-- Unconditionally makes a boolean setting `false`.
+function LuaSettings:makeFalse(key)
+    self:saveSetting(key, false)
+    return self
+end
+
+--- Toggles a boolean setting
+function LuaSettings:toggle(key)
+    if self:nilOrFalse(key) then
+        self:saveSetting(key, true)
+    else
+        self:saveSetting(key, false)
+    end
+    return self
+end
+
 -- Initializes settings per extension with default values
 function LuaSettings:initializeExtSettings(key, defaults, force_init)
     local curr = self:readSetting(key)

frontend/readhistory.lua

@@ -195,7 +195,7 @@ function ReadHistory:getPreviousFile(current_file)
 end
 
 function ReadHistory:fileDeleted(path)
-    if G_reader_settings:readSetting("autoremove_deleted_items_from_history") then
+    if G_reader_settings:isTrue("autoremove_deleted_items_from_history") then
         self:removeItemByPath(path)
     else
         -- Make it dimed
@@ -210,7 +210,7 @@ function ReadHistory:fileDeleted(path)
 end
 
 function ReadHistory:fileSettingsPurged(path)
-    if G_reader_settings:readSetting("autoremove_deleted_items_from_history") then
+    if G_reader_settings:isTrue("autoremove_deleted_items_from_history") then
         -- Also remove it from history on purge when that setting is enabled
         self:removeItemByPath(path)
     end

frontend/ui/data/settings_migration.lua

@@ -25,8 +25,8 @@ function SettingsMigration:migrateSettings(config)
     end
 
     -- Fine-grained CRe margins (#4945)
-    local old_margins = config:readSetting("copt_page_margins")
-    if old_margins then
+    if config:has("copt_page_margins") then
+        local old_margins = config:readSetting("copt_page_margins")
         logger.info("Migrating old", cfg_class, "CRe margin settings: L", old_margins[1], "T", old_margins[2], "R", old_margins[3], "B", old_margins[4])
         -- Format was: {left, top, right, bottom}
         config:saveSetting("copt_h_page_margins", {old_margins[1], old_margins[3]})
@@ -39,7 +39,7 @@ function SettingsMigration:migrateSettings(config)
     -- Space condensing to Word spacing
     -- From a single number (space condensing) to a table of 2 numbers ({space width scale, space condensing}).
     -- Be conservative and don't change space width scale: use 100%
-    if not config:readSetting("copt_word_spacing") and config:readSetting("copt_space_condensing") then
+    if config:hasNot("copt_word_spacing") and config:has("copt_space_condensing") then
         local space_condensing = config:readSetting("copt_space_condensing")
         logger.info("Migrating old", cfg_class, "CRe space condensing:", space_condensing)
         config:saveSetting("copt_word_spacing", { 100, space_condensing })

frontend/ui/elements/common_settings_menu_table.lua

@@ -157,8 +157,8 @@ if Device:isKobo() then
             return G_reader_settings:isTrue("ignore_power_sleepcover")
         end,
         callback = function()
-            G_reader_settings:flipNilOrFalse("ignore_power_sleepcover")
-            G_reader_settings:flipFalse("ignore_open_sleepcover")
+            G_reader_settings:toggle("ignore_power_sleepcover")
+            G_reader_settings:makeFalse("ignore_open_sleepcover")
             UIManager:show(InfoMessage:new{
                 text = _("This will take effect on next restart."),
             })
@@ -171,8 +171,8 @@ if Device:isKobo() then
             return G_reader_settings:isTrue("ignore_open_sleepcover")
         end,
         callback = function()
-            G_reader_settings:flipNilOrFalse("ignore_open_sleepcover")
-            G_reader_settings:flipFalse("ignore_power_sleepcover")
+            G_reader_settings:toggle("ignore_open_sleepcover")
+            G_reader_settings:makeFalse("ignore_power_sleepcover")
             UIManager:show(InfoMessage:new{
                 text = _("This will take effect on next restart."),
             })
@@ -436,7 +436,7 @@ if Device:hasKeys() then
 end
 
 -- Auto-save settings: default value, info text and warning, and menu items
-if G_reader_settings:readSetting("auto_save_settings_interval_minutes") == nil then
+if G_reader_settings:hasNot("auto_save_settings_interval_minutes") then
     -- Default to auto save every 15 mn
     G_reader_settings:saveSetting("auto_save_settings_interval_minutes", 15)
 end
@@ -593,8 +593,7 @@ common_settings.document = {
                 {
                     text = _("Open next file"),
                     enabled_func = function()
-                        return G_reader_settings:readSetting("collate")
-                            ~= "access"
+                        return G_reader_settings:readSetting("collate") ~= "access"
                     end,
                     checked_func = function()
                         return G_reader_settings:readSetting("end_document_action") == "next_file"

frontend/ui/elements/flash_keyboard.lua

@@ -3,10 +3,10 @@ local _ = require("gettext")
 return {
     text = _("Flash keyboard"),
     checked_func = function()
-        return G_reader_settings:readSetting("flash_keyboard") ~= false
+        return G_reader_settings:nilOrTrue("flash_keyboard")
     end,
     callback = function()
-        local disabled = G_reader_settings:readSetting("flash_keyboard") ~= false
+        local disabled = G_reader_settings:nilOrTrue("flash_keyboard")
         G_reader_settings:saveSetting("flash_keyboard", not disabled)
     end,
 }

frontend/ui/elements/screen_disable_double_tap_table.lua

@@ -5,10 +5,10 @@ local _ = require("gettext")
 return {
     text = _("Disable double tap"),
     checked_func = function()
-        return G_reader_settings:readSetting("disable_double_tap") ~= false
+        return G_reader_settings:nilOrTrue("disable_double_tap")
     end,
     callback = function()
-        local disabled = G_reader_settings:readSetting("disable_double_tap") ~= false
+        local disabled = G_reader_settings:nilOrTrue("disable_double_tap")
         G_reader_settings:saveSetting("disable_double_tap", not disabled)
         UIManager:show(InfoMessage:new{
             text = _("This will take effect on next restart."),

frontend/ui/elements/screensaver_menu.lua

@@ -1,31 +1,22 @@
 local Screensaver = require("ui/screensaver")
 local _ = require("gettext")
 
-local function screensaverType() return G_reader_settings:readSetting("screensaver_type") end
-local function screensaverDelay() return G_reader_settings:readSetting("screensaver_delay") end
-local function lastFile()
+local function hasLastFile()
+    if G_reader_settings:hasNot("lastfile") then
+        return false
+    end
+
     local lfs = require("libs/libkoreader-lfs")
     local last_file = G_reader_settings:readSetting("lastfile")
-    if last_file and lfs.attributes(last_file, "mode") == "file" then
-        return last_file
-    end
+    return last_file and lfs.attributes(last_file, "mode") == "file"
 end
-local function whiteBackground() return G_reader_settings:isTrue("screensaver_white_background") end
-local function noBackground() return G_reader_settings:isTrue("screensaver_no_background") end
-local function stretchImages() return G_reader_settings:isTrue("screensaver_stretch_images") end
-local function messagePosition() return G_reader_settings:readSetting("screensaver_message_position") end
-local function showMessage() return G_reader_settings:isTrue("screensaver_show_message") end
 
 return {
     {
         text = _("Use last book's cover as screensaver"),
-        enabled_func = function() return lastFile() ~= nil end,
+        enabled_func = hasLastFile,
         checked_func = function()
-            if screensaverType() == "cover" then
-                return true
-            else
-                return false
-            end
+            return G_reader_settings:readSetting("screensaver_type") == "cover"
         end,
         callback = function()
             G_reader_settings:saveSetting("screensaver_type", "cover")
@@ -33,13 +24,9 @@ return {
     },
     {
         text = _("Use book status as screensaver"),
-        enabled_func = function() return lastFile() ~= nil end,
+        enabled_func = hasLastFile,
         checked_func = function()
-            if screensaverType() == "bookstatus" then
-                return true
-            else
-                return false
-            end
+            return G_reader_settings:readSetting("screensaver_type") == "bookstatus"
         end,
         callback = function()
             G_reader_settings:saveSetting("screensaver_type", "bookstatus")
@@ -48,11 +35,7 @@ return {
     {
         text = _("Use random image from folder as screensaver"),
         checked_func = function()
-            if screensaverType() == "random_image" then
-                return true
-            else
-                return false
-            end
+            return G_reader_settings:readSetting("screensaver_type") == "random_image"
         end,
         callback = function()
             G_reader_settings:saveSetting("screensaver_type", "random_image")
@@ -61,11 +44,7 @@ return {
     {
         text = _("Use document cover as screensaver"),
         checked_func = function()
-            if screensaverType() == "document_cover" then
-                return true
-            else
-                return false
-            end
+            return G_reader_settings:readSetting("screensaver_type") == "document_cover"
         end,
         callback = function()
             G_reader_settings:saveSetting("screensaver_type", "document_cover")
@@ -74,11 +53,7 @@ return {
     {
         text = _("Use image as screensaver"),
         checked_func = function()
-            if screensaverType() == "image_file" then
-                return true
-            else
-                return false
-            end
+            return G_reader_settings:readSetting("screensaver_type") == "image_file"
         end,
         callback = function()
             G_reader_settings:saveSetting("screensaver_type", "image_file")
@@ -86,13 +61,9 @@ return {
     },
     {
         text = _("Use reading progress as screensaver"),
-        enabled_func = function() return Screensaver.getReaderProgress ~= nil and lastFile() ~= nil end,
+        enabled_func = function() return Screensaver.getReaderProgress ~= nil and hasLastFile() end,
         checked_func = function()
-            if screensaverType() == "readingprogress" then
-                return true
-            else
-                return false
-            end
+            return G_reader_settings:readSetting("screensaver_type") == "readingprogress"
         end,
         callback = function()
             G_reader_settings:saveSetting("screensaver_type", "readingprogress")
@@ -101,11 +72,7 @@ return {
     {
         text = _("Leave screen as it is"),
         checked_func = function()
-            if screensaverType() == "disable" then
-                return true
-            else
-                return false
-            end
+            return G_reader_settings:readSetting("screensaver_type") == "disable" or G_reader_settings:hasNot("screensaver_type")
         end,
         callback = function()
             G_reader_settings:saveSetting("screensaver_type", "disable")
@@ -114,9 +81,11 @@ return {
     },
     {
         text = _("Add message to screensaver"),
-        checked_func = showMessage,
+        checked_func = function()
+            return G_reader_settings:isTrue("screensaver_show_message") or G_reader_settings:hasNot("screensaver_type")
+        end,
         callback = function()
-            G_reader_settings:saveSetting("screensaver_show_message", not showMessage())
+            G_reader_settings:toggle("screensaver_show_message")
         end,
         separator = true,
     },
@@ -152,26 +121,39 @@ return {
                 end,
             },
             {
-                text = _("White background behind message and images"),
-                checked_func = whiteBackground,
+                text = _("Black background behind images"),
+                checked_func = function()
+                    return G_reader_settings:readSetting("screensaver_background") == "black" or G_reader_settings:hasNot("screensaver_background")
+                end,
                 callback = function()
-                    G_reader_settings:saveSetting("screensaver_white_background", not whiteBackground())
-                    G_reader_settings:flipFalse("screensaver_no_background")
+                    G_reader_settings:saveSetting("screensaver_background", "black")
+                end,
+            },
+            {
+                text = _("White background behind message and images"),
+                checked_func = function()
+                    return G_reader_settings:readSetting("screensaver_background") == "white"
+                end,
+                callback = function()
+                    G_reader_settings:saveSetting("screensaver_background", "white")
                 end,
             },
             {
                 text = _("Leave background as-is behind message and images"),
-                checked_func = noBackground,
+                checked_func = function()
+                    return G_reader_settings:readSetting("screensaver_background") == "none"
+                end,
                 callback = function()
-                    G_reader_settings:saveSetting("screensaver_no_background", not noBackground())
-                    G_reader_settings:flipFalse("screensaver_white_background")
+                    G_reader_settings:saveSetting("screensaver_background", "none")
                 end,
             },
             {
                 text = _("Stretch covers and images to fit screen"),
-                checked_func = stretchImages,
+                checked_func = function()
+                    return G_reader_settings:isTrue("screensaver_stretch_images")
+                end,
                 callback = function()
-                    G_reader_settings:saveSetting("screensaver_stretch_images", not stretchImages())
+                    G_reader_settings:toggle("screensaver_stretch_images")
                 end,
                 separator = true,
             },
@@ -181,7 +163,7 @@ return {
                     {
                         text = _("Top"),
                         checked_func = function()
-                            return messagePosition() == "top"
+                            return G_reader_settings:readSetting("screensaver_message_position") == "top"
                         end,
                         callback = function()
                             G_reader_settings:saveSetting("screensaver_message_position", "top")
@@ -190,7 +172,7 @@ return {
                     {
                         text = _("Middle"),
                         checked_func = function()
-                            return messagePosition() == "middle" or messagePosition() == nil
+                            return G_reader_settings:readSetting("screensaver_message_position") == "middle" or G_reader_settings:hasNot("screensaver_message_position")
                         end,
                         callback = function()
                             G_reader_settings:saveSetting("screensaver_message_position", "middle")
@@ -199,7 +181,7 @@ return {
                     {
                         text = _("Bottom"),
                         checked_func = function()
-                            return messagePosition() == "bottom"
+                            return G_reader_settings:readSetting("screensaver_message_position") == "bottom"
                         end,
                         callback = function()
                             G_reader_settings:saveSetting("screensaver_message_position", "bottom")
@@ -213,11 +195,7 @@ return {
                     {
                         text = _("Disable"),
                         checked_func = function()
-                            if screensaverDelay() == nil or screensaverDelay() == "disable" then
-                                return true
-                            else
-                                return false
-                            end
+                            return G_reader_settings:readSetting("screensaver_delay") == "disable" or G_reader_settings:hasNot("screensaver_delay")
                         end,
                         callback = function()
                             G_reader_settings:saveSetting("screensaver_delay", "disable")
@@ -226,11 +204,7 @@ return {
                     {
                         text = _("For 1 second"),
                         checked_func = function()
-                            if screensaverDelay() == "1" then
-                                return true
-                            else
-                                return false
-                            end
+                            return G_reader_settings:readSetting("screensaver_delay") == "1"
                         end,
                         callback = function()
                             G_reader_settings:saveSetting("screensaver_delay", "1")
@@ -239,11 +213,7 @@ return {
                     {
                         text = _("For 3 seconds"),
                         checked_func = function()
-                            if screensaverDelay() == "3" then
-                                return true
-                            else
-                                return false
-                            end
+                            return G_reader_settings:readSetting("screensaver_delay") == "3"
                         end,
                         callback = function()
                             G_reader_settings:saveSetting("screensaver_delay", "3")
@@ -252,11 +222,7 @@ return {
                     {
                         text = _("For 5 seconds"),
                         checked_func = function()
-                            if screensaverDelay() == "5" then
-                                return true
-                            else
-                                return false
-                            end
+                            return G_reader_settings:readSetting("screensaver_delay") == "5"
                         end,
                         callback = function()
                             G_reader_settings:saveSetting("screensaver_delay", "5")
@@ -265,11 +231,7 @@ return {
                     {
                         text = _("Until a tap"),
                         checked_func = function()
-                            if screensaverDelay() == "tap" then
-                                return true
-                            else
-                                return false
-                            end
+                            return G_reader_settings:readSetting("screensaver_delay") == "tap"
                         end,
                         callback = function()
                             G_reader_settings:saveSetting("screensaver_delay", "tap")

frontend/ui/network/manager.lua

@@ -25,7 +25,7 @@ function NetworkMgr:connectivityCheck(iter, callback, widget)
     if iter > 25 then
         logger.info("Failed to restore Wi-Fi (after", iter, "iterations)!")
         self.wifi_was_on = false
-        G_reader_settings:saveSetting("wifi_was_on", false)
+        G_reader_settings:makeFalse("wifi_was_on")
         -- If we abort, murder Wi-Fi and the async script first...
         if Device:hasWifiManager() and not Device:isEmulator() then
             os.execute("pkill -TERM restore-wifi-async.sh 2>/dev/null")
@@ -42,7 +42,7 @@ function NetworkMgr:connectivityCheck(iter, callback, widget)
 
     if NetworkMgr:isWifiOn() and NetworkMgr:isConnected() then
         self.wifi_was_on = true
-        G_reader_settings:saveSetting("wifi_was_on", true)
+        G_reader_settings:makeTrue("wifi_was_on")
         UIManager:broadcastEvent(Event:new("NetworkConnected"))
         logger.info("Wi-Fi successfully restored (after", iter, "iterations)!")
 
@@ -118,7 +118,7 @@ function NetworkMgr:promptWifiOn(complete_callback)
         ok_text = _("Turn on"),
         ok_callback = function()
             self.wifi_was_on = true
-            G_reader_settings:saveSetting("wifi_was_on", true)
+            G_reader_settings:makeTrue("wifi_was_on")
             self:turnOnWifi(complete_callback)
         end,
     })
@@ -130,7 +130,7 @@ function NetworkMgr:promptWifiOff(complete_callback)
         ok_text = _("Turn off"),
         ok_callback = function()
             self.wifi_was_on = false
-            G_reader_settings:saveSetting("wifi_was_on", false)
+            G_reader_settings:makeFalse("wifi_was_on")
             self:turnOffWifi(complete_callback)
         end,
     })
@@ -142,13 +142,13 @@ function NetworkMgr:promptWifi(complete_callback)
         choice1_text = _("Turn Wi-Fi off"),
         choice1_callback = function()
             self.wifi_was_on = false
-            G_reader_settings:saveSetting("wifi_was_on", false)
+            G_reader_settings:makeFalse("wifi_was_on")
             self:turnOffWifi(complete_callback)
         end,
         choice2_text = _("Connect"),
         choice2_callback = function()
             self.wifi_was_on = true
-            G_reader_settings:saveSetting("wifi_was_on", true)
+            G_reader_settings:makeTrue("wifi_was_on")
             self:turnOnWifi(complete_callback)
         end,
     })
@@ -268,9 +268,9 @@ function NetworkMgr:setHTTPProxy(proxy)
     http.PROXY = proxy
     if proxy then
         G_reader_settings:saveSetting("http_proxy", proxy)
-        G_reader_settings:saveSetting("http_proxy_enabled", true)
+        G_reader_settings:makeTrue("http_proxy_enabled")
     else
-        G_reader_settings:saveSetting("http_proxy_enabled", false)
+        G_reader_settings:makeFalse("http_proxy_enabled")
     end
 end
 
@@ -376,7 +376,7 @@ function NetworkMgr:getWifiToggleMenuTable()
                             --       (It's called connect_callback there).
                             --       This makes this branch somewhat hard to reach, which is why it gets a dedicated prompt below...
                             self.wifi_was_on = false
-                            G_reader_settings:saveSetting("wifi_was_on", false)
+                            G_reader_settings:makeFalse("wifi_was_on")
                             -- NOTE: We're limiting this to only a few platforms, as it might be actually harmful on some devices.
                             --       The intent being to unload kernel modules, and make a subsequent turnOnWifi behave sanely.
                             --       PB: Relies on netagent, no idea what it does, but it's not using this codepath anyway (!hasWifiToggle)

frontend/ui/translator.lua

@@ -201,7 +201,7 @@ function Translator:genSettingsMenu()
                     return T("%1 (%2)", lang_name, lang_key)
                 end,
                 checked_func = function()
-                    if G_reader_settings:readSetting(setting_name) then
+                    if G_reader_settings:has(setting_name) then
                         return lang_key == G_reader_settings:readSetting(setting_name)
                     else
                         return lang_key == default_checked_item
@@ -252,7 +252,7 @@ end
 
 function Translator:getSourceLanguage()
     if G_reader_settings:isFalse("translator_from_auto_detect") and
-            G_reader_settings:readSetting("translator_from_language") then
+            G_reader_settings:has("translator_from_language") then
         return G_reader_settings:readSetting("translator_from_language")
     end
     return AUTODETECT_LANGUAGE -- "auto"

frontend/ui/uimanager.lua

@@ -61,7 +61,9 @@ function UIManager:init()
         self._entered_poweroff_stage = true
         Device.orig_rotation_mode = Device.screen:getRotationMode()
         Screen:setRotationMode(Screen.ORIENTATION_PORTRAIT)
-        require("ui/screensaver"):show("poweroff", _("Powered off"))
+        local Screensaver = require("ui/screensaver")
+        Screensaver:setup("poweroff", _("Powered off"))
+        Screensaver:show()
         if Device:needsScreenRefreshAfterResume() then
             Screen:refreshFull()
         end
@@ -78,7 +80,9 @@ function UIManager:init()
         self._entered_poweroff_stage = true
         Device.orig_rotation_mode = Device.screen:getRotationMode()
         Screen:setRotationMode(Screen.ORIENTATION_PORTRAIT)
-        require("ui/screensaver"):show("reboot", _("Rebooting…"))
+        local Screensaver = require("ui/screensaver")
+        Screensaver:setup("reboot", _("Rebooting…"))
+        Screensaver:show()
         if Device:needsScreenRefreshAfterResume() then
             Screen:refreshFull()
         end
@@ -137,12 +141,12 @@ function UIManager:init()
             end
         end
         -- Sleep Cover handling
-        if G_reader_settings:readSetting("ignore_power_sleepcover") then
+        if G_reader_settings:isTrue("ignore_power_sleepcover") then
             -- NOTE: The hardware event itself will wake the kernel up if it's in suspend (:/).
             --       Let the unexpected wakeup guard handle that.
             self.event_handlers["SleepCoverClosed"] = nil
             self.event_handlers["SleepCoverOpened"] = nil
-        elseif G_reader_settings:readSetting("ignore_open_sleepcover") then
+        elseif G_reader_settings:isTrue("ignore_open_sleepcover") then
             -- Just ignore wakeup events, and do NOT set is_cover_closed,
             -- so device/generic/device will let us use the power button to wake ;).
             self.event_handlers["SleepCoverClosed"] = function()

frontend/ui/widget/configdialog.lua

@@ -189,7 +189,7 @@ function ConfigOption:init()
     local padding_button = Size.padding.button -- padding for underline below letters and icons
 
     --- @todo Restore setting when there are more advanced settings.
-    --local show_advanced = G_reader_settings:readSetting("show_advanced") or false
+    --local show_advanced = G_reader_settings:isTrue("show_advanced")
     local show_advanced = true
 
     -- Get the width needed by the longest option name shown on the left

frontend/ui/widget/dictquicklookup.lua

@@ -342,9 +342,9 @@ function DictQuickLookup:init()
                                 dir = last_file:match("(.*)/")
                             end
                         end
-                        if not dir then dir = G_reader_settings:readSetting("wikipedia_save_dir") end
-                        if not dir then dir = G_reader_settings:readSetting("home_dir") end
-                        if not dir then dir = require("apps/filemanager/filemanagerutil").getDefaultDir() end
+                        if not dir then dir = G_reader_settings:readSetting("wikipedia_save_dir")
+                                           or G_reader_settings:readSetting("home_dir")
+                                           or require("apps/filemanager/filemanagerutil").getDefaultDir() end
                         if not dir or not util.pathExists(dir) then
                             UIManager:show(InfoMessage:new{
                                 text = _("No directory to save article to could be found."),

frontend/ui/widget/filechooser.lua

@@ -25,10 +25,47 @@ local FileChooser = Menu:extend{
     show_path = true,
     parent = nil,
     show_hidden = nil,
-    exclude_dirs = {"%.sdr$"},
+    -- NOTE: Input is *always* a relative entry name
+    exclude_dirs = {
+        -- KOReader / Kindle
+        "%.sdr$",
+        -- Kobo
+        "^%.adobe%-digital%-editions$",
+        "^%.kobo$",
+        "^%.kobo%-images$",
+        -- macOS
+        "^%.fseventsd$",
+        "^%.Trashes$",
+        "^%.Spotlight%-V100$",
+        -- *nix
+        "^%.Trash$",
+        "^%.Trash%-%d+$",
+        -- Windows
+        "^RECYCLED$",
+        "^RECYCLER$",
+        "^%$Recycle%.Bin$",
+        "^System Volume Information$",
+        -- Plato
+        "^%.thumbnail%-previews$",
+        "^%.reading%-states$",
+    },
+    exclude_files = {
+        -- macOS
+        "^%.DS_Store$",
+        -- *nix
+        "^%.directory$",
+        -- Windows
+        "^Thumbs%.db$",
+        -- Calibre
+        "^driveinfo%.calibre$",
+        "^metadata%.calibre$",
+        -- Plato
+        "^%.fat32%-epoch$",
+        "^%.metadata%.json$",
+    },
     collate = "strcoll", -- or collate = "access",
     reverse_collate = false,
-    path_items = {}, -- store last browsed location(item index) for each path
+    path_items = {}, -- store last browsed location (item index) for each path
     goto_letter = true,
 }
 
@@ -39,13 +76,20 @@ local unreadable_dir_content = {}
 
 function FileChooser:init()
     self.width = Screen:getWidth()
-    -- common dir filter
-    self.dir_filter = function(dirname)
+    -- Standard dir exclusion list
+    self.show_dir = function(dirname)
         for _, pattern in ipairs(self.exclude_dirs) do
             if dirname:match(pattern) then return false end
         end
         return true
     end
+    -- Standard file exclusion list
+    self.show_file = function(filename)
+        for _, pattern in ipairs(self.exclude_files) do
+            if filename:match(pattern) then return false end
+        end
+        return true
+    end
     self.list = function(path, dirs, files, count_only)
         -- lfs.dir directory without permission will give error
         local ok, iter, dir_obj = pcall(lfs.dir, path)
@@ -53,17 +97,19 @@ function FileChooser:init()
             unreadable_dir_content[path] = nil
             for f in iter, dir_obj do
                 if count_only then
-                    if self.dir_filter(f) and ((not self.show_hidden and not util.stringStartsWith(f, "."))
-                        or (self.show_hidden and f ~= "." and f ~= ".." and not util.stringStartsWith(f, "._")))
+                    if ((not self.show_hidden and not util.stringStartsWith(f, "."))
+                         or (self.show_hidden and f ~= "." and f ~= ".." and not util.stringStartsWith(f, "._")))
+                         and self.show_dir(f)
+                         and self.show_file(f)
                     then
                         table.insert(dirs, true)
                     end
-                elseif self.show_hidden or not string.match(f, "^%.[^.]") then
+                elseif self.show_hidden or not util.stringStartsWith(f, ".") then
                     local filename = path.."/"..f
                     local attributes = lfs.attributes(filename)
                     if attributes ~= nil then
                         if attributes.mode == "directory" and f ~= "." and f ~= ".." then
-                            if self.dir_filter(filename) then
+                            if self.show_dir(f) then
                                 table.insert(dirs, {name = f,
                                                     suffix = getFileNameSuffix(f),
                                                     fullpath = filename,
@@ -71,22 +117,24 @@ function FileChooser:init()
                             end
                         -- Always ignore macOS resource forks.
                         elseif attributes.mode == "file" and not util.stringStartsWith(f, "._") then
-                            if self.file_filter == nil or self.file_filter(filename) or self.show_unsupported then
-                                local percent_finished = 0
-                                if self.collate == "percent_unopened_first" or self.collate == "percent_unopened_last" then
-                                    if DocSettings:hasSidecarFile(filename) then
-                                        local docinfo = DocSettings:open(filename)
-                                        percent_finished = docinfo.data.percent_finished
-                                        if percent_finished == nil then
-                                            percent_finished = 0
+                            if self.show_file(f) then
+                                if self.file_filter == nil or self.file_filter(filename) or self.show_unsupported then
+                                    local percent_finished = 0
+                                    if self.collate == "percent_unopened_first" or self.collate == "percent_unopened_last" then
+                                        if DocSettings:hasSidecarFile(filename) then
+                                            local docinfo = DocSettings:open(filename)
+                                            percent_finished = docinfo.data.percent_finished
+                                            if percent_finished == nil then
+                                                percent_finished = 0
+                                            end
                                         end
                                     end
+                                    table.insert(files, {name = f,
+                                                        suffix = getFileNameSuffix(f),
+                                                        fullpath = filename,
+                                                        attr = attributes,
+                                                        percent_finished = percent_finished })
                                 end
-                                table.insert(files, {name = f,
-                                                     suffix = getFileNameSuffix(f),
-                                                     fullpath = filename,
-                                                     attr = attributes,
-                                                     percent_finished = percent_finished })
                             end
                         end
                     end

frontend/ui/widget/pathchooser.lua

@@ -37,7 +37,7 @@ function PathChooser:init()
             self.title = _("Long-press to select")
         end
     end
-    self.show_hidden = G_reader_settings:readSetting("show_hidden")
+    self.show_hidden = G_reader_settings:isTrue("show_hidden")
     if not self.show_files then
         self.file_filter = function() return false end -- filter out regular files
     end

frontend/ui/widget/virtualkeyboard.lua

@@ -218,7 +218,7 @@ function VirtualKey:init()
     (self.keyboard.umlautmode_keys[self.label] ~= nil and self.keyboard.umlautmode) then
         self[1].background = Blitbuffer.COLOR_LIGHT_GRAY
     end
-    self.flash_keyboard = G_reader_settings:readSetting("flash_keyboard") ~= false
+    self.flash_keyboard = G_reader_settings:nilOrTrue("flash_keyboard")
 end
 
 function VirtualKey:genkeyboardLayoutKeyChars()

frontend/util.lua

@@ -373,6 +373,44 @@ function util.arrayAppend(t1, t2)
     end
 end
 
+--[[--
+Remove elements from an array, fast.
+
+Swap & pop, like <http://lua-users.org/lists/lua-l/2013-11/msg00027.html> / <https://stackoverflow.com/a/28942022>, but preserving order.
+c.f., <https://stackoverflow.com/a/53038524>
+
+@table t Lua array to filter
+@func keep_cb Filtering callback. Takes three arguments: table, index, new index. Returns true to *keep* the item. See link above for potential uses of the third argument.
+
+@usage
+
+local foo = { "a", "b", "c", "b", "d", "e" }
+local function drop_b(t, i, j)
+    -- Discard any item with value "b"
+    return t[i] ~= "b"
+end
+util.arrayRemove(foo, drop_b)
+]]
+function util.arrayRemove(t, keep_cb)
+    local j, n = 1, #t
+
+    for i = 1, n do
+        if keep_cb(t, i, j) then
+            -- Move i's kept value to j's position, if it's not already there.
+            if i ~= j then
+                t[j] = t[i]
+                t[i] = nil
+            end
+            -- Increment position of where we'll place the next kept value.
+            j = j + 1
+        else
+            t[i] = nil
+        end
+    end
+
+    return t
+end
+
 --- Reverse array elements in-place in table t
 ---- @param t Lua table
 function util.arrayReverse(t)
@@ -389,7 +427,7 @@ end
 --- and if so, return the index.
 ---- @param t Lua table
 ---- @param v
----- @function callback(v1, v2)
+---- @func callback(v1, v2)
 function util.arrayContains(t, v, cb)
     cb = cb or function(v1, v2) return v1 == v2 end
     for _k, _v in ipairs(t) do
@@ -654,7 +692,7 @@ end
 
 --- Recursively scan directory for files inside
 -- @string path
--- @function callback(fullpath, name, attr)
+-- @func callback(fullpath, name, attr)
 function util.findFiles(dir, cb)
     local function scan(current)
         local ok, iter, dir_obj = pcall(lfs.dir, current)

plugins/autosuspend.koplugin/main.lua

@@ -9,8 +9,6 @@ if not Device:isCervantes() and
     return { disabled = true, }
 end
 
-local DataStorage = require("datastorage")
-local LuaSettings = require("luasettings")
 local PluginShare = require("pluginshare")
 local UIManager = require("ui/uimanager")
 local WidgetContainer = require("ui/widget/container/widgetcontainer")
@@ -19,39 +17,19 @@ local _ = require("gettext")
 local T = require("ffi/util").template
 
 local default_autoshutdown_timeout_seconds = 3*24*60*60
+local default_auto_suspend_timeout_seconds = 60*60
 
 local AutoSuspend = WidgetContainer:new{
     name = "autosuspend",
     is_doc_only = false,
     autoshutdown_timeout_seconds = G_reader_settings:readSetting("autoshutdown_timeout_seconds") or default_autoshutdown_timeout_seconds,
-    settings = LuaSettings:open(DataStorage:getSettingsDir() .. "/koboautosuspend.lua"),
+    auto_suspend_timeout_seconds = G_reader_settings:readSetting("auto_suspend_timeout_seconds") or default_auto_suspend_timeout_seconds,
     last_action_sec = os.time(),
     standby_prevented = false,
 }
 
-function AutoSuspend:_readTimeoutSecFrom(settings)
-    local sec = settings:readSetting("auto_suspend_timeout_seconds")
-    if type(sec) == "number" then
-        return sec
-    end
-    return -1
-end
-
-function AutoSuspend:_readTimeoutSec()
-    local candidates = { self.settings, G_reader_settings }
-    for _, candidate in ipairs(candidates) do
-        local sec = self:_readTimeoutSecFrom(candidate)
-        if sec ~= -1 then
-            return sec
-        end
-    end
-
-    -- default setting is 60 minutes
-    return 60 * 60
-end
-
 function AutoSuspend:_enabled()
-    return self.auto_suspend_sec > 0
+    return self.auto_suspend_timeout_seconds > 0
 end
 
 function AutoSuspend:_enabledShutdown()
@@ -67,11 +45,11 @@ function AutoSuspend:_schedule()
     local delay_suspend, delay_shutdown
 
     if PluginShare.pause_auto_suspend or Device.standby_prevented or Device.powerd:isCharging() then
-        delay_suspend = self.auto_suspend_sec
+        delay_suspend = self.auto_suspend_timeout_seconds
         delay_shutdown = self.autoshutdown_timeout_seconds
     else
         local now_ts = os.time()
-        delay_suspend = self.last_action_sec + self.auto_suspend_sec - now_ts
+        delay_suspend = self.last_action_sec + self.auto_suspend_timeout_seconds - now_ts
         delay_shutdown = self.last_action_sec + self.autoshutdown_timeout_seconds - now_ts
     end
 
@@ -111,7 +89,6 @@ end
 function AutoSuspend:init()
     if Device:isPocketBook() and not Device:canSuspend() then return end
     UIManager.event_hook:registerWidget("InputEvent", self)
-    self.auto_suspend_sec = self:_readTimeoutSec()
     self:_unschedule()
     self:_start()
     -- self.ui is nil in the testsuite
@@ -158,22 +135,20 @@ function AutoSuspend:addToMainMenu(menu_items)
             local InfoMessage = require("ui/widget/infomessage")
             local Screen = Device.screen
             local SpinWidget = require("ui/widget/spinwidget")
-            local curr_items = G_reader_settings:readSetting("auto_suspend_timeout_seconds") or 60*60
             local autosuspend_spin = SpinWidget:new {
                 width = math.floor(Screen:getWidth() * 0.6),
-                value = curr_items / 60,
+                value = self.auto_suspend_timeout_seconds / 60,
                 value_min = 5,
                 value_max = 240,
                 value_hold_step = 15,
                 ok_text = _("Set timeout"),
                 title_text = _("Timeout in minutes"),
                 callback = function(autosuspend_spin)
-                    local autosuspend_timeout_seconds = autosuspend_spin.value * 60
-                    self.auto_suspend_sec = autosuspend_timeout_seconds
-                    G_reader_settings:saveSetting("auto_suspend_timeout_seconds", autosuspend_timeout_seconds)
+                    self.auto_suspend_timeout_seconds = autosuspend_spin.value * 60
+                    G_reader_settings:saveSetting("auto_suspend_timeout_seconds", self.auto_suspend_timeout_seconds)
                     UIManager:show(InfoMessage:new{
                         text = T(_("The system will automatically suspend after %1 minutes of inactivity."),
-                            string.format("%.2f", autosuspend_timeout_seconds/60)),
+                            string.format("%.2f", self.auto_suspend_timeout_seconds / 60)),
                         timeout = 3,
                     })
                     self:_unschedule()
@@ -191,10 +166,9 @@ function AutoSuspend:addToMainMenu(menu_items)
             local InfoMessage = require("ui/widget/infomessage")
             local Screen = Device.screen
             local SpinWidget = require("ui/widget/spinwidget")
-            local curr_items = self.autoshutdown_timeout_seconds
             local autosuspend_spin = SpinWidget:new {
                 width = math.floor(Screen:getWidth() * 0.6),
-                value = curr_items / 60 / 60,
+                value = self.autoshutdown_timeout_seconds / 60 / 60,
                 -- About a minute, good for testing and battery life fanatics.
                 -- Just high enough to avoid an instant shutdown death scenario.
                 value_min = 0.017,
@@ -206,12 +180,11 @@ function AutoSuspend:addToMainMenu(menu_items)
                 ok_text = _("Set timeout"),
                 title_text = _("Timeout in hours"),
                 callback = function(autosuspend_spin)
-                    local autoshutdown_timeout_seconds = math.floor(autosuspend_spin.value * 60*60)
-                    self.autoshutdown_timeout_seconds = autoshutdown_timeout_seconds
-                    G_reader_settings:saveSetting("autoshutdown_timeout_seconds", autoshutdown_timeout_seconds)
+                    self.autoshutdown_timeout_seconds = math.floor(autosuspend_spin.value * 60 * 60)
+                    G_reader_settings:saveSetting("autoshutdown_timeout_seconds", self.autoshutdown_timeout_seconds)
                     UIManager:show(InfoMessage:new{
                         text = T(_("The system will automatically shut down after %1 hours of inactivity."),
-                            string.format("%.2f", autoshutdown_timeout_seconds/60/60)),
+                            string.format("%.2f", self.autoshutdown_timeout_seconds / 60 / 60)),
                         timeout = 3,
                     })
                     self:_unschedule()

plugins/autoturn.koplugin/main.lua

@@ -132,7 +132,7 @@ function AutoTurn:addToMainMenu(menu_items)
                 title_text = _("Timeout in seconds"),
                 cancel_callback = function()
                     self.enabled = false
-                    G_reader_settings:flipFalse("autoturn_enabled")
+                    G_reader_settings:makeFalse("autoturn_enabled")
                     self:_deprecateLastTask()
                     menu:updateItems()
                 end,
@@ -140,7 +140,7 @@ function AutoTurn:addToMainMenu(menu_items)
                     self.autoturn_sec = autoturn_spin.value
                     G_reader_settings:saveSetting("autoturn_timeout_seconds", autoturn_spin.value)
                     self.enabled = true
-                    G_reader_settings:flipTrue("autoturn_enabled")
+                    G_reader_settings:makeTrue("autoturn_enabled")
                     self:_deprecateLastTask()
                     self:_start()
                     menu:updateItems()

plugins/calibre.koplugin/main.lua

@@ -133,10 +133,10 @@ function Calibre:getSearchMenuTable()
                         text = path,
                         keep_menu_open = true,
                         checked_func = function()
-                            return cache:readSetting(path)
+                            return cache:isTrue(path)
                         end,
                         callback = function()
-                            cache:saveSetting(path, not cache:readSetting(path))
+                            cache:toggle(path)
                             cache:flush()
                             CalibreSearch:invalidateCache()
                         end,
@@ -165,8 +165,7 @@ function Calibre:getSearchMenuTable()
                 return G_reader_settings:isTrue("calibre_search_from_reader")
             end,
             callback = function()
-                local current = G_reader_settings:isTrue("calibre_search_from_reader")
-                G_reader_settings:saveSetting("calibre_search_from_reader", not current)
+                G_reader_settings:toggle("calibre_search_from_reader")
                 UIManager:show(InfoMessage:new{
                     text = _("This will take effect on next restart."),
                 })

plugins/calibre.koplugin/metadata.lua

@@ -49,7 +49,7 @@ local function findCalibreFiles(dir)
     local function existOrLast(file)
         local fullname
         local options = { file, "." .. file }
-        for _, option in pairs(options) do
+        for _, option in ipairs(options) do
             fullname = dir .. "/" .. option
             if util.fileExists(fullname) then
                 return true, fullname
@@ -144,11 +144,10 @@ end
 
 -- remove a book from our books table
 function CalibreMetadata:removeBook(lpath)
-    for index, book in ipairs(self.books) do
-        if book.lpath == lpath then
-            table.remove(self.books, index)
-        end
+    local function drop_lpath(t, i, j)
+        return t[i].lpath ~= lpath
     end
+    util.arrayRemove(self.books, drop_lpath)
 end
 
 -- gets the uuid and index of a book from its path
@@ -165,7 +164,7 @@ end
 function CalibreMetadata:getBookId(index)
     local book = {}
     book.priKey = index
-    for _, key in pairs({ "uuid", "lpath", "last_modified"}) do
+    for _, key in ipairs({"uuid", "lpath", "last_modified"}) do
         book[key] = self.books[index][key]
     end
     return book

plugins/calibre.koplugin/search.lua

@@ -297,7 +297,7 @@ end
 
 -- find books, series or tags
 function CalibreSearch:find(option)
-    for _, opt in pairs(self.search_options) do
+    for _, opt in ipairs(self.search_options) do
         self[opt] = G_reader_settings:nilOrTrue("calibre_search_"..opt)
     end
 

plugins/calibre.koplugin/wireless.lua

@@ -26,7 +26,7 @@ require("ffi/zeromq_h")
 local extensions = require("extensions")
 local function getExtensionPathLengths()
     local t = {}
-    for _, v in pairs(extensions) do
+    for _, v in ipairs(extensions) do
         -- magic number from calibre, see
         -- https://github.com/koreader/koreader/pull/6177#discussion_r430753964
         t[v] = 37

plugins/coverbrowser.koplugin/main.lua

@@ -66,7 +66,7 @@ function CoverBrowser:init()
             BookInfoManager:saveSetting("filemanager_display_mode", "list_image_meta")
             BookInfoManager:saveSetting("history_display_mode", "mosaic_image")
         end
-        G_reader_settings:saveSetting("coverbrowser_initial_default_setup_done", true)
+        G_reader_settings:makeTrue("coverbrowser_initial_default_setup_done")
     end
 
     self:setupFileManagerDisplayMode(BookInfoManager:getSetting("filemanager_display_mode"))

plugins/coverimage.koplugin/main.lua

@@ -81,7 +81,7 @@ function CoverImage:cleanUpImage()
 end
 
 function CoverImage:createCoverImage(doc_settings)
-   if self.enabled and not doc_settings:readSetting("exclude_cover_image") == true then
+    if self.enabled and doc_settings:nilOrFalse("exclude_cover_image") then
         local cover_image = self.ui.document:getCoverPageImage()
         if cover_image then
             local s_w, s_h = Device.screen:getWidth(), Device.screen:getHeight()
@@ -426,14 +426,14 @@ function CoverImage:addToMainMenu(menu_items)
             {
                 text = _("Exclude this book cover"),
                 checked_func = function()
-                    return self.ui and self.ui.doc_settings and self.ui.doc_settings:readSetting("exclude_cover_image") == true
+                    return self.ui and self.ui.doc_settings and self.ui.doc_settings:isTrue("exclude_cover_image")
                 end,
                 callback = function()
-                    if self.ui.doc_settings:readSetting("exclude_cover_image") == true then
-                        self.ui.doc_settings:saveSetting("exclude_cover_image", false)
+                    if self.ui.doc_settings:isTrue("exclude_cover_image") then
+                        self.ui.doc_settings:makeFalse("exclude_cover_image")
                         self:createCoverImage(self.ui.doc_settings)
                     else
-                        self.ui.doc_settings:saveSetting("exclude_cover_image", true)
+                        self.ui.doc_settings:makeTrue("exclude_cover_image")
                         self:cleanUpImage()
                     end
                     self.ui:saveSettings()

plugins/gestures.koplugin/main.lua

@@ -118,8 +118,8 @@ function Gestures:init()
     if not lfs.attributes(gestures_path, "mode") then
         FFIUtil.copyFile(defaults_path, gestures_path)
     end
-    self.ignore_hold_corners = G_reader_settings:readSetting("ignore_hold_corners")
-    self.multiswipes_enabled = G_reader_settings:readSetting("multiswipes_enabled")
+    self.ignore_hold_corners = G_reader_settings:isTrue("ignore_hold_corners")
+    self.multiswipes_enabled = G_reader_settings:isTrue("multiswipes_enabled")
     self.is_docless = self.ui == nil or self.ui.document == nil
     self.ges_mode = self.is_docless and "gesture_fm" or "gesture_reader"
     self.defaults = LuaSettings:open(defaults_path).data[self.ges_mode]
@@ -682,7 +682,7 @@ function Gestures:addToMainMenu(menu_items)
                 text = _("Turn on multiswipes"),
                 checked_func = function() return self.multiswipes_enabled end,
                 callback = function()
-                    G_reader_settings:saveSetting("multiswipes_enabled", not self.multiswipes_enabled)
+                    G_reader_settings:toggle("multiswipes_enabled")
                     self.multiswipes_enabled = G_reader_settings:isTrue("multiswipes_enabled")
                 end,
                 help_text = multiswipes_info_text,
@@ -1118,12 +1118,12 @@ function Gestures:multiswipeAction(multiswipe_directions, ges)
             text = _("You have just performed your first multiswipe gesture.") .."\n\n".. multiswipes_info_text,
             ok_text = _("Turn on"),
             ok_callback = function()
-                G_reader_settings:saveSetting("multiswipes_enabled", true)
+                G_reader_settings:makeTrue("multiswipes_enabled")
                 self.multiswipes_enabled = true
             end,
             cancel_text = _("Turn off"),
             cancel_callback = function()
-                G_reader_settings:saveSetting("multiswipes_enabled", false)
+                G_reader_settings:makeFalse("multiswipes_enabled")
                 self.multiswipes_enabled = false
             end,
         })

plugins/gestures.koplugin/migration.lua

@@ -193,7 +193,7 @@ function Migration:migrateGestures(caller)
         end
     end
     caller.settings_data:flush()
-    G_reader_settings:saveSetting("gestures_migrated", true)
+    G_reader_settings:makeTrue("gestures_migrated")
 end
 
 return Migration

plugins/kosync.koplugin/main.lua

@@ -15,7 +15,7 @@ local random = require("random")
 local T = require("ffi/util").template
 local _ = require("gettext")
 
-if not G_reader_settings:readSetting("device_id") then
+if G_reader_settings:hasNot("device_id") then
     G_reader_settings:saveSetting("device_id", random.uuid())
 end
 
@@ -104,6 +104,7 @@ function KOSync:onDispatcherRegisterActions()
 end
 
 function KOSync:onReaderReady()
+    --- @todo: Viable candidate for a port to the new readSetting API
     local settings = G_reader_settings:readSetting("kosync") or {}
     self.kosync_custom_server = settings.custom_server
     self.kosync_username = settings.username

plugins/newsdownloader.koplugin/main.lua

@@ -97,12 +97,10 @@ function NewsDownloader:addToMainMenu(menu_items)
                 text = _("Never download images"),
                 keep_menu_open = true,
                 checked_func = function()
-                    return news_downloader_settings:readSetting("never_download_images")
+                    return news_downloader_settings:isTrue("never_download_images")
                 end,
                 callback = function()
-                    local never_download_images = news_downloader_settings:readSetting("never_download_images") or false
-                    logger.info("NewsDownloader: previous never_download_images: ", never_download_images)
-                    news_downloader_settings:saveSetting("never_download_images", not never_download_images)
+                    news_downloader_settings:toggle("never_download_images")
                     news_downloader_settings:flush()
                 end,
             },
@@ -176,11 +174,11 @@ function NewsDownloader:loadConfigAndProcessFeeds()
         return
     end
 
-    local never_download_images = news_downloader_settings:readSetting("never_download_images") or false
+    local never_download_images = news_downloader_settings:isTrue("never_download_images")
 
     local unsupported_feeds_urls = {}
 
-    local total_feed_entries = table.getn(feed_config)
+    local total_feed_entries = #feed_config
     for idx, feed in ipairs(feed_config) do
         local url = feed[1]
         local limit = feed.limit

plugins/opds.koplugin/opdsbrowser.lua

@@ -36,8 +36,34 @@ local CatalogCache = Cache:new{
 }
 
 local OPDSBrowser = Menu:extend{
-    opds_servers = {},
+    opds_servers = G_reader_settings:readSetting("opds_servers", {
+        {
+            title = "Project Gutenberg",
+            url = "https://m.gutenberg.org/ebooks.opds/?format=opds",
+        },
+        {
+            title = "Feedbooks",
+            url = "https://catalog.feedbooks.com/catalog/public_domain.atom",
+        },
+        {
+            title = "ManyBooks",
+            url = "http://manybooks.net/opds/index.php",
+        },
+        {
+            title = "Internet Archive",
+            url = "https://bookserver.archive.org/",
+        },
+        {
+            title = "textos.info (Spanish)",
+            url = "https://www.textos.info/catalogo.atom",
+        },
+        {
+            title = "Gallica (French)",
+            url = "https://gallica.bnf.fr/opds",
+        },
+    }),
     calibre_name = _("Local calibre library"),
+    calibre_opds = G_reader_settings:readSetting("calibre_opds", {}),
 
     catalog_type = "application/atom%+xml",
     search_type = "application/opensearchdescription%+xml",
@@ -53,38 +79,13 @@ local OPDSBrowser = Menu:extend{
 }
 
 function OPDSBrowser:init()
-    local servers = G_reader_settings:readSetting("opds_servers")
-    if not servers then -- If there are no saved servers, add some defaults
-        servers = {
-          {
-            title = "Project Gutenberg",
-            url = "https://m.gutenberg.org/ebooks.opds/?format=opds",
-          },
-          {
-             title = "Feedbooks",
-             url = "https://catalog.feedbooks.com/catalog/public_domain.atom",
-          },
-          {
-             title = "ManyBooks",
-             url = "http://manybooks.net/opds/index.php",
-          },
-          {
-             title = "Internet Archive",
-             url = "https://bookserver.archive.org/",
-          },
-          {
-             title = "textos.info (Spanish)",
-             url = "https://www.textos.info/catalogo.atom",
-          },
-          {
-             title = "Gallica (French)",
-             url = "https://gallica.bnf.fr/opds",
-          },
-        }
-        G_reader_settings:saveSetting("opds_servers", servers)
-    elseif servers[4] and servers[4].title == "Internet Archive" and servers[4].url == "http://bookserver.archive.org/catalog/"  then
-        servers[4].url = "https://bookserver.archive.org"
+    -- Update deprecated URLs
+    for _, server in ipairs(self.opds_servers) do
+        if server.url == "http://bookserver.archive.org/catalog/" then
+            server.url = "https://bookserver.archive.org"
+        end
     end
+
     self.item_table = self:genItemTableFromRoot()
     self.catalog_title = nil
     Menu.init(self) -- call parent's init()
@@ -92,7 +93,6 @@ end
 
 function OPDSBrowser:addServerFromInput(fields)
     logger.info("New OPDS catalog input:", fields)
-    local servers = G_reader_settings:readSetting("opds_servers") or {}
     local new_server = {
         title = fields[1],
         url = (fields[2]:match("^%a+://") and fields[2] or "http://" .. fields[2]),
@@ -101,31 +101,28 @@ function OPDSBrowser:addServerFromInput(fields)
         -- Allow empty passwords
         password = fields[4],
     }
-    table.insert(servers, new_server)
-    G_reader_settings:saveSetting("opds_servers", servers)
+    table.insert(self.opds_servers, new_server)
     self:init()
 end
 
 function OPDSBrowser:editCalibreFromInput(fields)
     logger.dbg("Edit calibre server input:", fields)
-    local calibre = G_reader_settings:readSetting("calibre_opds") or {}
     if fields[1] then
-        calibre.host = fields[1]
+        self.calibre_opds.host = fields[1]
     end
     if tonumber(fields[2]) then
-        calibre.port = fields[2]
+        self.calibre_opds.port = fields[2]
     end
     if fields[3] and fields[3] ~= "" then
-        calibre.username = fields[3]
+        self.calibre_opds.username = fields[3]
     else
-        calibre.username = nil
+        self.calibre_opds.username = nil
     end
     if fields[4] then
-        calibre.password = fields[4]
+        self.calibre_opds.password = fields[4]
     else
-        calibre.password = nil
+        self.calibre_opds.password = nil
     end
-    G_reader_settings:saveSetting("calibre_opds", calibre)
     self:init()
 end
 
@@ -178,25 +175,24 @@ function OPDSBrowser:addNewCatalog()
 end
 
 function OPDSBrowser:editCalibreServer()
-    local calibre = G_reader_settings:readSetting("calibre_opds") or {}
     self.add_server_dialog = MultiInputDialog:new{
         title = _("Edit local calibre host and port"),
         fields = {
             {
                 --- @todo get IP address of current device
-                text = calibre.host or "192.168.1.1",
+                text = self.calibre_opds.host or "192.168.1.1",
                 hint = _("calibre host"),
             },
             {
-                text = calibre.port and tostring(calibre.port) or "8080",
+                text = self.calibre_opds.port and tostring(self.calibre_opds.port) or "8080",
                 hint = _("calibre port"),
             },
             {
-                text = calibre.username or "",
+                text = self.calibre_opds.username or "",
                 hint = _("Username (optional)"),
             },
             {
-                text = calibre.password or "",
+                text = self.calibre_opds.password or "",
                 hint = _("Password (optional)"),
                 text_type = "password",
             },
@@ -229,8 +225,7 @@ end
 
 function OPDSBrowser:genItemTableFromRoot()
     local item_table = {}
-    local added_servers = G_reader_settings:readSetting("opds_servers") or {}
-    for _, server in ipairs(added_servers) do
+    for _, server in ipairs(self.opds_servers) do
         table.insert(item_table, {
             text = server.title,
             content = server.subtitle,
@@ -242,8 +237,7 @@ function OPDSBrowser:genItemTableFromRoot()
             searchable = server.searchable,
         })
     end
-    local calibre_opds = G_reader_settings:readSetting("calibre_opds") or {}
-    if not calibre_opds.host or not calibre_opds.port then
+    if not self.calibre_opds.host or not self.calibre_opds.port then
         table.insert(item_table, {
             text = self.calibre_name,
             callback = function()
@@ -255,9 +249,9 @@ function OPDSBrowser:genItemTableFromRoot()
         table.insert(item_table, {
             text = self.calibre_name,
             url = string.format("http://%s:%d/opds",
-                calibre_opds.host, calibre_opds.port),
-            username = calibre_opds.username,
-            password = calibre_opds.password,
+                self.calibre_opds.host, self.calibre_opds.port),
+            username = self.calibre_opds.username,
+            password = self.calibre_opds.password,
             editable = true,
             deletable = false,
             searchable = false,
@@ -772,8 +766,7 @@ end
 
 function OPDSBrowser:editServerFromInput(item, fields)
     logger.info("Edit OPDS catalog input:", fields)
-    local servers = {}
-    for _, server in ipairs(G_reader_settings:readSetting("opds_servers") or {}) do
+    for _, server in ipairs(self.opds_servers) do
         if server.title == item.text or server.url == item.url then
             server.title = fields[1]
             server.url = (fields[2]:match("^%a+://") and fields[2] or "http://" .. fields[2])
@@ -781,9 +774,7 @@ function OPDSBrowser:editServerFromInput(item, fields)
             server.username = fields[3] ~= "" and fields[3] or nil
             server.password = fields[4]
         end
-        table.insert(servers, server)
     end
-    G_reader_settings:saveSetting("opds_servers", servers)
     self:init()
 end
 
@@ -838,13 +829,12 @@ end
 
 function OPDSBrowser:deleteOPDSServer(item)
     logger.info("Delete OPDS server:", item)
-    local servers = {}
-    for _, server in ipairs(G_reader_settings:readSetting("opds_servers") or {}) do
-        if server.title ~= item.text or server.url ~= item.url then
-            table.insert(servers, server)
+    for i = #self.opds_servers, 1, -1 do
+        local server = self.opds_servers[i]
+        if server.title == item.text and server.url == item.url then
+            table.remove(self.opds_servers, i)
         end
     end
-    G_reader_settings:saveSetting("opds_servers", servers)
     self:init()
 end
 

plugins/perceptionexpander.koplugin/main.lua

@@ -30,7 +30,7 @@ local PerceptionExpander = Widget:extend{
 function PerceptionExpander:init()
     if not self.settings then self:readSettingsFile() end
 
-    self.is_enabled = self.settings:readSetting("is_enabled") or false
+    self.is_enabled = self.settings:isTrue("is_enabled")
     if not self.is_enabled then
         return
     end

plugins/statistics.koplugin/main.lua

@@ -35,7 +35,7 @@ local DEFAULT_CALENDAR_NB_BOOK_SPANS = 3
 local DB_SCHEMA_VERSION = 20201022
 
 -- This is the query used to compute the total time spent reading distinct pages of the book,
--- capped at self.page_max_read_sec per distinct page.
+-- capped at self.settings.max_sec per distinct page.
 -- c.f., comments in insertDB
 local STATISTICS_SQL_BOOK_CAPPED_TOTALS_QUERY = [[
     SELECT count(*),
@@ -137,22 +137,15 @@ function ReaderStatistics:init()
     end
     self.start_current_period = os.time()
     self:resetVolatileStats()
-    local settings = G_reader_settings:readSetting("statistics") or {}
-    self.page_min_read_sec = tonumber(settings.min_sec)
-    self.page_max_read_sec = tonumber(settings.max_sec)
-    self.calendar_start_day_of_week = settings.calendar_start_day_of_week
-    self.calendar_nb_book_spans = settings.calendar_nb_book_spans
-    self.calendar_show_histogram = settings.calendar_show_histogram
-    self.calendar_browse_future_months = settings.calendar_browse_future_months
-    self.is_enabled = not (settings.is_enabled == false)
-    self.convert_to_db = settings.convert_to_db
+    self.settings = G_reader_settings:readSetting("statistics", {})
+    self.settings.is_enabled = not (self.settings.is_enabled == false)
     self.ui.menu:registerToMainMenu(self)
     self:checkInitDatabase()
     BookStatusWidget.getStats = function()
-        return self:getStatsBookStatus(self.id_curr_book, self.is_enabled)
+        return self:getStatsBookStatus(self.id_curr_book, self.settings.is_enabled)
     end
     ReaderFooter.getAvgTimePerPage = function()
-        if self.is_enabled then
+        if self.settings.is_enabled then
             return self.avg_time
         end
     end
@@ -177,7 +170,7 @@ function ReaderStatistics:init()
 end
 
 function ReaderStatistics:initData()
-    if self:isDocless() or not self.is_enabled then
+    if self:isDocless() or not self.settings.is_enabled then
         return
     end
     -- first execution
@@ -206,7 +199,7 @@ function ReaderStatistics:initData()
         self.avg_time = self.book_read_time / self.book_read_pages
     else
         -- NOTE: Possibly less weird-looking than initializing this to 0?
-        self.avg_time = math.floor(0.50 * self.page_max_read_sec)
+        self.avg_time = math.floor(0.50 * self.settings.max_sec)
         logger.dbg("ReaderStatistics: Initializing average time per page at 50% of the max value, i.e.,", self.avg_time)
     end
 end
@@ -276,7 +269,7 @@ end
 
 function ReaderStatistics:checkInitDatabase()
     local conn = SQ3.open(db_location)
-    if self.convert_to_db then      -- if conversion to sqlite DB has already been done
+    if self.settings.convert_to_db then      -- if conversion to sqlite DB has already been done
         if not conn:exec("PRAGMA table_info('book');") then
             UIManager:show(ConfirmBox:new{
                 text = T(_([[
@@ -352,7 +345,7 @@ Do you want to create an empty database?
             conn = SQ3.open(db_location)
         end
     else  -- Migrate stats for books in history from metadata.lua to sqlite database
-        self.convert_to_db = true
+        self.settings.convert_to_db = true
         if not conn:exec("PRAGMA table_info('book');") then
             local filename_first_history, quickstart_filename, __
             if #ReadHistory.hist == 1 then
@@ -379,7 +372,6 @@ Please wait…
                 self:createDB(conn)
             end
         end
-        self:saveSettings()
     end
     conn:close()
 end
@@ -593,8 +585,8 @@ function ReaderStatistics:addBookStatToDB(book_stats, conn)
         conn:exec('BEGIN;')
         stmt = conn:prepare("INSERT OR IGNORE INTO page_stat VALUES(?, ?, ?, ?);")
         local avg_time = math.ceil(book_stats.total_time_in_sec / read_pages)
-        if avg_time > self.page_max_read_sec then
-            avg_time = self.page_max_read_sec
+        if avg_time > self.settings.max_sec then
+            avg_time = self.settings.max_sec
         end
         local first_read_page = book_stats.performance_in_pages[sorted_performance[1]]
         if first_read_page > 1 then
@@ -606,10 +598,10 @@ function ReaderStatistics:addBookStatToDB(book_stats, conn)
         for i=2, #sorted_performance do
             start_open_page = sorted_performance[i-1]
             local diff_time = sorted_performance[i] - sorted_performance[i-1]
-            if diff_time <= self.page_max_read_sec then
+            if diff_time <= self.settings.max_sec then
                 stmt:reset():bind(id_book, book_stats.performance_in_pages[sorted_performance[i-1]],
                     start_open_page, diff_time):step()
-            elseif diff_time > self.page_max_read_sec then --and diff_time <= 2 * avg_time then
+            elseif diff_time > self.settings.max_sec then --and diff_time <= 2 * avg_time then
                 stmt:reset():bind(id_book, book_stats.performance_in_pages[sorted_performance[i-1]],
                     start_open_page, avg_time):step()
             end
@@ -640,7 +632,7 @@ function ReaderStatistics:migrateToDB(conn)
     local nr_of_conv_books = 0
     local exclude_titles = {}
     for _, v in pairs(ReadHistory.hist) do
-        local book_stats = DocSettings:open(v.file):readSetting('stats')
+        local book_stats = DocSettings:open(v.file):readSetting("stats")
         if book_stats and book_stats.title == "" then
             book_stats.title = v.file:match("^.+/(.+)$")
         end
@@ -767,9 +759,9 @@ function ReaderStatistics:insertDB(id_book, updated_pagecount)
 
     -- NOTE: See the tail end of the discussions in #6761 for more context on the choice of this heuristic.
     --       Basically, we're counting distinct pages,
-    --       while making sure the sum of durations per distinct page is clamped to self.page_max_read_sec
+    --       while making sure the sum of durations per distinct page is clamped to self.settings.max_sec
     --       This is expressly tailored to a fairer computation of self.avg_time ;).
-    local book_read_pages, book_read_time = conn:rowexec(string.format(STATISTICS_SQL_BOOK_CAPPED_TOTALS_QUERY, self.page_max_read_sec, id_book))
+    local book_read_pages, book_read_time = conn:rowexec(string.format(STATISTICS_SQL_BOOK_CAPPED_TOTALS_QUERY, self.settings.max_sec, id_book))
     -- NOTE: What we cache in the book table is the plain uncapped sum (mainly for deleteBooksByTotalDuration's benefit)...
     local total_read_pages, total_read_time = conn:rowexec(string.format(STATISTICS_SQL_BOOK_TOTALS_QUERY, id_book))
 
@@ -810,7 +802,7 @@ function ReaderStatistics:getPageTimeTotalStats(id_book)
     end
     local conn = SQ3.open(db_location)
     -- NOTE: Similarly, this one is used for time-based estimates and averages, so, use the capped variant
-    local total_pages, total_time = conn:rowexec(string.format(STATISTICS_SQL_BOOK_CAPPED_TOTALS_QUERY, self.page_max_read_sec, id_book))
+    local total_pages, total_time = conn:rowexec(string.format(STATISTICS_SQL_BOOK_CAPPED_TOTALS_QUERY, self.settings.max_sec, id_book))
     conn:close()
 
     if total_pages then
@@ -838,23 +830,22 @@ end
 function ReaderStatistics:getStatisticEnabledMenuItem()
     return {
         text = _("Enabled"),
-        checked_func = function() return self.is_enabled end,
+        checked_func = function() return self.settings.is_enabled end,
         callback = function()
             -- if was enabled, have to save data to file
-            if self.is_enabled and not self:isDocless() then
+            if self.settings.is_enabled and not self:isDocless() then
                 self:insertDB(self.id_curr_book)
                 self.ui.doc_settings:saveSetting("stats", self.data)
             end
 
-            self.is_enabled = not self.is_enabled
+            self.settings.is_enabled = not self.settings.is_enabled
             -- if was disabled have to get data from db
-            if self.is_enabled and not self:isDocless() then
+            if self.settings.is_enabled and not self:isDocless() then
                 self:initData()
                 self.start_current_period = os.time()
                 self.curr_page = self.ui:getCurrentPage()
                 self:resetVolatileStats(self.start_current_period)
             end
-            self:saveSettings()
             if not self:isDocless() then
                 self.view.footer:onUpdateFooter()
             end
@@ -873,21 +864,21 @@ function ReaderStatistics:addToMainMenu(menu_items)
                     {
                         text_func = function()
                             return T(_("Read page duration limits: %1 s / %2 s"),
-                                self.page_min_read_sec, self.page_max_read_sec)
+                                self.settings.min_sec, self.settings.max_sec)
                         end,
                         callback = function(touchmenu_instance)
                             local DoubleSpinWidget = require("/ui/widget/doublespinwidget")
                             local durations_widget
                             durations_widget = DoubleSpinWidget:new{
                                 left_text = _("Min"),
-                                left_value = self.page_min_read_sec,
+                                left_value = self.settings.min_sec,
                                 left_default = DEFAULT_MIN_READ_SEC,
                                 left_min = 3,
                                 left_max = 120,
                                 left_step = 1,
                                 left_hold_step = 10,
                                 right_text = _("Max"),
-                                right_value = self.page_max_read_sec,
+                                right_value = self.settings.max_sec,
                                 right_default = DEFAULT_MAX_READ_SEC,
                                 right_min = 10,
                                 right_max = 7200,
@@ -906,9 +897,8 @@ The max value ensures a page you stay on for a long time (because you fell aslee
                                     if min > max then
                                         min, max = max, min
                                     end
-                                    self.page_min_read_sec = min
-                                    self.page_max_read_sec = max
-                                    self:saveSettings()
+                                    self.settings.min_sec = min
+                                    self.settings.max_sec = max
                                     UIManager:close(durations_widget)
                                     touchmenu_instance:updateItems()
                                 end,
@@ -921,52 +911,52 @@ The max value ensures a page you stay on for a long time (because you fell aslee
                     {
                         text_func = function()
                             return T(_("Calendar weeks start on %1"),
-                                longDayOfWeekTranslation[weekDays[self.calendar_start_day_of_week]])
+                                longDayOfWeekTranslation[weekDays[self.settings.calendar_start_day_of_week]])
                         end,
                         sub_item_table = {
                             { -- Friday (Bangladesh and Maldives)
                                 text = longDayOfWeekTranslation[weekDays[6]],
-                                checked_func = function() return self.calendar_start_day_of_week == 6 end,
-                                callback = function() self.calendar_start_day_of_week = 6 end
+                                checked_func = function() return self.settings.calendar_start_day_of_week == 6 end,
+                                callback = function() self.settings.calendar_start_day_of_week = 6 end
                             },
                             { -- Saturday (some Middle East countries)
                                 text = longDayOfWeekTranslation[weekDays[7]],
-                                checked_func = function() return self.calendar_start_day_of_week == 7 end,
-                                callback = function() self.calendar_start_day_of_week = 7 end
+                                checked_func = function() return self.settings.calendar_start_day_of_week == 7 end,
+                                callback = function() self.settings.calendar_start_day_of_week = 7 end
                             },
                             { -- Sunday
                                 text = longDayOfWeekTranslation[weekDays[1]],
-                                checked_func = function() return self.calendar_start_day_of_week == 1 end,
-                                callback = function() self.calendar_start_day_of_week = 1 end
+                                checked_func = function() return self.settings.calendar_start_day_of_week == 1 end,
+                                callback = function() self.settings.calendar_start_day_of_week = 1 end
                             },
                             { -- Monday
                                 text = longDayOfWeekTranslation[weekDays[2]],
-                                checked_func = function() return self.calendar_start_day_of_week == 2 end,
-                                callback = function() self.calendar_start_day_of_week = 2 end
+                                checked_func = function() return self.settings.calendar_start_day_of_week == 2 end,
+                                callback = function() self.settings.calendar_start_day_of_week = 2 end
                             },
                         },
                     },
                     {
                         text_func = function()
-                            return T(_("Books per calendar day: %1"), self.calendar_nb_book_spans)
+                            return T(_("Books per calendar day: %1"), self.settings.calendar_nb_book_spans)
                         end,
                         callback = function(touchmenu_instance)
                             local SpinWidget = require("ui/widget/spinwidget")
                             UIManager:show(SpinWidget:new{
                                 width = math.floor(Screen:getWidth() * 0.6),
-                                value = self.calendar_nb_book_spans,
+                                value = self.settings.calendar_nb_book_spans,
                                 value_min = 1,
                                 value_max = 5,
                                 ok_text = _("Set"),
                                 title_text =  _("Books per calendar day"),
                                 info_text = _("Set the max number of book spans to show for a day"),
                                 callback = function(spin)
-                                    self.calendar_nb_book_spans = spin.value
+                                    self.settings.calendar_nb_book_spans = spin.value
                                     touchmenu_instance:updateItems()
                                 end,
                                 extra_text = _("Use default"),
                                 extra_callback = function()
-                                    self.calendar_nb_book_spans = DEFAULT_CALENDAR_NB_BOOK_SPANS
+                                    self.settings.calendar_nb_book_spans = DEFAULT_CALENDAR_NB_BOOK_SPANS
                                     touchmenu_instance:updateItems()
                                 end
                             })
@@ -975,16 +965,16 @@ The max value ensures a page you stay on for a long time (because you fell aslee
                     },
                     {
                         text = _("Show hourly histogram in calendar days"),
-                        checked_func = function() return self.calendar_show_histogram end,
+                        checked_func = function() return self.settings.calendar_show_histogram end,
                         callback = function()
-                            self.calendar_show_histogram = not self.calendar_show_histogram
+                            self.settings.calendar_show_histogram = not self.settings.calendar_show_histogram
                         end,
                     },
                     {
                         text = _("Allow browsing coming months"),
-                        checked_func = function() return self.calendar_browse_future_months end,
+                        checked_func = function() return self.settings.calendar_browse_future_months end,
                         callback = function()
-                            self.calendar_browse_future_months = not self.calendar_browse_future_months
+                            self.settings.calendar_browse_future_months = not self.settings.calendar_browse_future_months
                         end,
                     },
                 },
@@ -1003,7 +993,7 @@ The max value ensures a page you stay on for a long time (because you fell aslee
                         kv_pairs = self:getCurrentStat(self.id_curr_book),
                     })
                 end,
-                enabled_func = function() return not self:isDocless() and self.is_enabled end,
+                enabled_func = function() return not self:isDocless() and self.settings.is_enabled end,
             },
             {
                 text = _("Reading progress"),
@@ -1307,7 +1297,7 @@ function ReaderStatistics:getCurrentStat(id_book)
         -- Current book statistics
         -- Includes re-reads
         { _("Total time spent on this book"), util.secondsToClock(total_time_book, false) },
-        -- Capped to self.page_max_read_sec per distinct page
+        -- Capped to self.settings.max_sec per distinct page
         { _("Time spent reading this book"), util.secondsToClock(book_read_time, false) },
         -- per days
         { _("Reading started"), os.date("%Y-%m-%d (%H:%M)", tonumber(first_open))},
@@ -1922,7 +1912,7 @@ function ReaderStatistics:genResetBookSubItemTable()
         callback = function()
             self:resetCurrentBook()
         end,
-        enabled_func = function() return not self:isDocless() and self.is_enabled and self.id_curr_book end,
+        enabled_func = function() return not self:isDocless() and self.settings.is_enabled and self.id_curr_book end,
         separator = true,
     })
     table.insert(sub_item_table, {
@@ -2052,7 +2042,7 @@ function ReaderStatistics:resetCurrentBook()
             -- We also need to reset the time/page/avg tracking
             self.book_read_pages = 0
             self.book_read_time = 0
-            self.avg_time = math.floor(0.50 * self.page_max_read_sec)
+            self.avg_time = math.floor(0.50 * self.settings.max_sec)
             logger.dbg("ReaderStatistics: Initializing average time per page at 50% of the max value, i.e.,", self.avg_time)
 
             -- And the current volatile stats
@@ -2143,7 +2133,7 @@ function ReaderStatistics:onPosUpdate(pos, pageno)
 end
 
 function ReaderStatistics:onPageUpdate(pageno)
-    if self:isDocless() or not self.is_enabled then
+    if self:isDocless() or not self.settings.is_enabled then
         return
     end
 
@@ -2174,7 +2164,7 @@ function ReaderStatistics:onPageUpdate(pageno)
     -- NOTE: If all goes well, given the earlier curr_page != pageno check, curr_duration should always be 0 here.
     -- Compute the difference between now and the previous page's last timestamp
     local diff_time = now_ts - then_ts
-    if diff_time >= self.page_min_read_sec and diff_time <= self.page_max_read_sec then
+    if diff_time >= self.settings.min_sec and diff_time <= self.settings.max_sec then
         self.mem_read_time = self.mem_read_time + diff_time
         -- If it's the first time we're computing a duration for this page, count it as read
         if #page_data == 1 and curr_duration == 0 then
@@ -2182,13 +2172,13 @@ function ReaderStatistics:onPageUpdate(pageno)
         end
         -- Update the tuple with the computed duration
         data_tuple[2] = curr_duration + diff_time
-    elseif diff_time > self.page_max_read_sec then
-        self.mem_read_time = self.mem_read_time + self.page_max_read_sec
+    elseif diff_time > self.settings.max_sec then
+        self.mem_read_time = self.mem_read_time + self.settings.max_sec
         if #page_data == 1 and curr_duration == 0 then
             self.mem_read_pages = self.mem_read_pages + 1
         end
         -- Update the tuple with the computed duration
-        data_tuple[2] = curr_duration + self.page_max_read_sec
+        data_tuple[2] = curr_duration + self.settings.max_sec
     end
 
     -- We want a flush to db every 50 page turns
@@ -2238,20 +2228,20 @@ function ReaderStatistics:importFromFile(base_path, item)
 end
 
 function ReaderStatistics:onCloseDocument()
-    if not self:isDocless() and self.is_enabled then
+    if not self:isDocless() and self.settings.is_enabled then
         self.ui.doc_settings:saveSetting("stats", self.data)
         self:insertDB(self.id_curr_book)
     end
 end
 
 function ReaderStatistics:onAddHighlight()
-    if self.is_enabled then
+    if self.settings.is_enabled then
         self.data.highlights = self.data.highlights + 1
     end
 end
 
 function ReaderStatistics:onDelHighlight()
-    if self.is_enabled then
+    if self.settings.is_enabled then
         if self.data.highlights > 0 then
             self.data.highlights = self.data.highlights - 1
         end
@@ -2259,14 +2249,13 @@ function ReaderStatistics:onDelHighlight()
 end
 
 function ReaderStatistics:onAddNote()
-    if self.is_enabled then
+    if self.settings.is_enabled then
         self.data.notes = self.data.notes + 1
     end
 end
 
 -- Triggered by auto_save_settings_interval_minutes
 function ReaderStatistics:onSaveSettings()
-    self:saveSettings()
     if not self:isDocless() then
         self.ui.doc_settings:saveSetting("stats", self.data)
         self:insertDB(self.id_curr_book)
@@ -2287,20 +2276,6 @@ function ReaderStatistics:onResume()
     self:resetVolatileStats(self.start_current_period)
 end
 
-function ReaderStatistics:saveSettings()
-    local settings = {
-        min_sec = self.page_min_read_sec,
-        max_sec = self.page_max_read_sec,
-        is_enabled = self.is_enabled,
-        convert_to_db = self.convert_to_db,
-        calendar_start_day_of_week = self.calendar_start_day_of_week,
-        calendar_nb_book_spans = self.calendar_nb_book_spans,
-        calendar_show_histogram = self.calendar_show_histogram,
-        calendar_browse_future_months = self.calendar_browse_future_months,
-    }
-    G_reader_settings:saveSetting("statistics", settings)
-end
-
 function ReaderStatistics:onReadSettings(config)
     self.data = config.data.stats or {}
 end
@@ -2319,10 +2294,10 @@ function ReaderStatistics:getCalendarView()
         monthTranslation = monthTranslation,
         shortDayOfWeekTranslation = shortDayOfWeekTranslation,
         longDayOfWeekTranslation = longDayOfWeekTranslation,
-        start_day_of_week = self.calendar_start_day_of_week,
-        nb_book_spans = self.calendar_nb_book_spans,
-        show_hourly_histogram = self.calendar_show_histogram,
-        browse_future_months = self.calendar_browse_future_months,
+        start_day_of_week = self.settings.calendar_start_day_of_week,
+        nb_book_spans = self.settings.calendar_nb_book_spans,
+        show_hourly_histogram = self.settings.calendar_show_histogram,
+        browse_future_months = self.settings.calendar_browse_future_months,
     }
 end
 
@@ -2433,7 +2408,7 @@ function ReaderStatistics:onShowReaderProgress()
 end
 
 function ReaderStatistics:onShowBookStats()
-    if self:isDocless() or not self.is_enabled then return end
+    if self:isDocless() or not self.settings.is_enabled then return end
     local stats = KeyValuePage:new{
         title = _("Current statistics"),
         kv_pairs = self:getCurrentStat(self.id_curr_book),

plugins/terminal.koplugin/main.lua

@@ -38,11 +38,10 @@ end
 function Terminal:init()
     self:onDispatcherRegisterActions()
     self.ui.menu:registerToMainMenu(self)
-    self.shortcuts = self.settings:readSetting("shortcuts") or {}
+    self.shortcuts = self.settings:readSetting("shortcuts", {})
 end
 
 function Terminal:saveShortcuts()
-    self.settings:saveSetting("shortcuts", self.shortcuts)
     self.settings:flush()
     UIManager:show(InfoMessage:new{
         text = _("Shortcuts saved"),
@@ -294,13 +293,12 @@ function Terminal:editName(item)
 end
 
 function Terminal:deleteShortcut(item)
-    local shortcuts = {}
-    for _, element in ipairs(self.shortcuts) do
-        if element.text ~= item.text and element.commands ~= item.commands then
-            table.insert(shortcuts, element)
+    for i = #self.shortcuts, 1, -1 do
+        local element = self.shortcuts[i]
+        if element.text == item.text and element.commands == item.commands then
+            table.remove(self.shortcuts, i)
         end
     end
-    self.shortcuts = shortcuts
     self:saveShortcuts()
     self:manageShortcuts()
 end

plugins/texteditor.koplugin/main.lua

@@ -45,6 +45,7 @@ function TextEditor:loadSettings()
         return
     end
     self.settings = LuaSettings:open(self.settings_file)
+    -- NOTE: addToHistory assigns a new object
     self.history = self.settings:readSetting("history") or {}
     self.last_view_pos = self.settings:readSetting("last_view_pos") or {}
     self.last_path = self.settings:readSetting("last_path") or ffiutil.realpath(DataStorage:getDataDir())
@@ -56,10 +57,10 @@ function TextEditor:loadSettings()
     --
     -- Allow users to set their prefered font manually in text_editor.lua
     -- (sadly, not via TextEditor itself, as they would be overriden on close)
-    if self.settings:readSetting("normal_font") then
+    if self.settings:has("normal_font") then
         self.normal_font = self.settings:readSetting("normal_font")
     end
-    if self.settings:readSetting("monospace_font") then
+    if self.settings:has("monospace_font") then
         self.monospace_font = self.settings:readSetting("monospace_font")
     end
     self.auto_para_direction = self.settings:nilOrTrue("auto_para_direction")
@@ -254,7 +255,7 @@ function TextEditor:execWhenDoneFunc()
 end
 
 function TextEditor:removeFromHistory(file_path)
-    for i=#self.history, 1, -1 do
+    for i = #self.history, 1, -1 do
         if self.history[i] == file_path then
             table.remove(self.history, i)
         end

plugins/zsync.koplugin/main.lua

@@ -233,7 +233,7 @@ function ZSync:subscribe()
     self.received = {}
     local zsync = self
     require("ui/downloadmgr"):new{
-        show_hidden = G_reader_settings:readSetting("show_hidden"),
+        show_hidden = G_reader_settings:isTrue("show_hidden"),
         onConfirm = function(inbox)
             G_reader_settings:saveSetting("inbox_dir", inbox)
             zsync:onChooseInbox(inbox)

reader.lua

@@ -212,7 +212,7 @@ local UIManager = require("ui/uimanager")
 -- and we are not (yet?) able to guess that fact)
 if Device:hasColorScreen() and not G_reader_settings:has("color_rendering") then
     -- enable it to prevent further display of this message
-    G_reader_settings:saveSetting("color_rendering", true)
+    G_reader_settings:makeTrue("color_rendering")
     local InfoMessage = require("ui/widget/infomessage")
     UIManager:show(InfoMessage:new{
         text = _("Documents will be rendered in color on this device.\nIf your device is grayscale, you can disable color rendering in the screen sub-menu for reduced memory usage."),

spec/unit/autofrontlight_spec.lua

@@ -41,7 +41,7 @@ describe("AutoFrontlight widget tests", function()
         Device.input.waitEvent = function() end
         require("luasettings"):
             open(require("datastorage"):getSettingsDir() .. "/autofrontlight.lua"):
-            saveSetting("enable", "true"):
+            saveSetting("enable", true):
             close()
 
         UIManager = require("ui/uimanager")

spec/unit/luadata_spec.lua

@@ -45,7 +45,7 @@ describe("luadata module", function()
 
         Settings:saveSetting("key", {
             a = "b",
-            c = "true",
+            c = "True",
             d = false,
         })
 
@@ -55,7 +55,7 @@ describe("luadata module", function()
         assert.True(child:has("a"))
         assert.are.equal(child:readSetting("a"), "b")
         assert.True(child:has("c"))
-        assert.True(child:isTrue("c"))
+        assert.False(child:isTrue("c")) -- It's a string, not a bool!
         assert.True(child:has("d"))
         assert.True(child:isFalse("d"))
         assert.False(child:isTrue("e"))

spec/unit/luasettings_spec.lua

@@ -45,7 +45,7 @@ describe("luasettings module", function()
 
         Settings:saveSetting("key", {
             a = "b",
-            c = "true",
+            c = "True",
             d = false,
         })
 
@@ -55,7 +55,7 @@ describe("luasettings module", function()
         assert.True(child:has("a"))
         assert.are.equal(child:readSetting("a"), "b")
         assert.True(child:has("c"))
-        assert.True(child:isTrue("c"))
+        assert.False(child:isTrue("c")) -- It's a string, not a bool!
         assert.True(child:has("d"))
         assert.True(child:isFalse("d"))
         assert.False(child:isTrue("e"))

spec/unit/readhistory_spec.lua

@@ -367,7 +367,7 @@ describe("ReadHistory module", function()
 
     it("should automatically remove deleted items from history if setting has been set",
        function()
-           G_reader_settings:saveSetting("autoremove_deleted_items_from_history", "true")
+           G_reader_settings:saveSetting("autoremove_deleted_items_from_history", true)
            testAutoRemoveDeletedItems()
            G_reader_settings:delSetting("autoremove_deleted_items_from_history")
        end)
@@ -380,7 +380,7 @@ describe("ReadHistory module", function()
 
     it("should not automatically remove deleted items from history if setting has been set to false",
        function()
-           G_reader_settings:saveSetting("autoremove_deleted_items_from_history", "false")
+           G_reader_settings:saveSetting("autoremove_deleted_items_from_history", false)
            testDoNotAutoRemoveDeletedItems()
            G_reader_settings:delSetting("autoremove_deleted_items_from_history")
        end)