PDF written highlights: fix boxes, trash cached tiles

TileCacheItem: add created_ts property.
Document: manage a tile_cache_validity_ts and ignore
older cached tiles.
This timestamps is updated when highlights are written
as annotations in, or deleted from, the PDF, so we can
get the most current rendered bitmap from MuPDF and
avoid highlight ghosts on old tiles.
Save this timestamp in doc settings so older cached to
disk tiles will also be ignored across re-openings.
Bump base for: mupdf.lua: update frontend pboxes with
MuPDF adjusted ones.

frontend/apps/reader/modules/readerview.lua

@@ -760,6 +760,7 @@ In combination with zoom to fit page, page height, content height, content or co
 end
 
 function ReaderView:onReadSettings(config)
+    self.document:setTileCacheValidity(config:readSetting("tile_cache_validity_ts"))
     self.render_mode = config:readSetting("render_mode") or 0
     local rotation_mode = nil
     local locked = G_reader_settings:isTrue("lock_rotation")
@@ -888,6 +889,7 @@ function ReaderView:onPageGapUpdate(page_gap)
 end
 
 function ReaderView:onSaveSettings()
+    self.ui.doc_settings:saveSetting("tile_cache_validity_ts", self.document:getTileCacheValidity())
     self.ui.doc_settings:saveSetting("render_mode", self.render_mode)
     -- Don't etch the current rotation in stone when sticky rotation is enabled
     local locked = G_reader_settings:isTrue("lock_rotation")

frontend/document/document.lua

@@ -372,6 +372,18 @@ function Document:postRenderPage()
     return nil
 end
 
+function Document:getTileCacheValidity()
+    return self.tile_cache_validity_ts
+end
+
+function Document:setTileCacheValidity(ts)
+    self.tile_cache_validity_ts = ts
+end
+
+function Document:resetTileCacheValidity()
+    self.tile_cache_validity_ts = os.time()
+end
+
 function Document:getFullPageHash(pageno, zoom, rotation, gamma, render_mode, color)
     return "renderpg|"..self.file.."|"..self.mod_time.."|"..pageno.."|"
                     ..zoom.."|"..rotation.."|"..gamma.."|"..render_mode..(color and "|color" or "")
@@ -386,7 +398,16 @@ function Document:renderPage(pageno, rect, zoom, rotation, gamma, render_mode)
         hash_excerpt = hash.."|"..tostring(rect)
         tile = DocCache:check(hash_excerpt)
     end
-    if tile then return tile end
+    if tile then
+        if self.tile_cache_validity_ts then
+            if tile.created_ts and tile.created_ts >= self.tile_cache_validity_ts then
+                return tile
+            end
+            logger.dbg("discarding stale cached tile")
+        else
+            return tile
+        end
+    end
 
     self:preRenderPage()
 
@@ -411,6 +432,7 @@ function Document:renderPage(pageno, rect, zoom, rotation, gamma, render_mode)
     -- prepare cache item with contained blitbuffer
     tile = TileCacheItem:new{
         persistent = true,
+        created_ts = os.time(),
         excerpt = size,
         pageno = pageno,
         bb = Blitbuffer.new(size.w, size.h, self.render_color and self.color_bb_type or nil)

frontend/document/pdfdocument.lua

@@ -208,6 +208,20 @@ local function _quadpointsFromPboxes(pboxes)
     return quadpoints, n
 end
 
+local function _quadpointsToPboxes(quadpoints, n)
+    -- reverse of previous function
+    local pboxes = {}
+    for i=1, n do
+        table.insert(pboxes, {
+            x = quadpoints[8*i-4],
+            y = quadpoints[8*i-3],
+            w = quadpoints[8*i-6] - quadpoints[8*i-4],
+            h = quadpoints[8*i-5] - quadpoints[8*i-3],
+        })
+    end
+    return pboxes
+end
+
 function PdfDocument:saveHighlight(pageno, item)
     local can_write = self:_checkIfWritable()
     if can_write ~= true then return can_write end
@@ -223,8 +237,12 @@ function PdfDocument:saveHighlight(pageno, item)
     elseif item.drawer == "strikeout" then
         annot_type = C.PDF_ANNOT_STRIKEOUT
     end
-    page:addMarkupAnnotation(quadpoints, n, annot_type)
+    page:addMarkupAnnotation(quadpoints, n, annot_type) -- may update/adjust quadpoints
+    -- Update pboxes with the possibly adjusted coordinates (this will have it updated
+    -- in self.view.highlight.saved[page])
+    item.pboxes = _quadpointsToPboxes(quadpoints, n)
     page:close()
+    self:resetTileCacheValidity()
 end
 
 function PdfDocument:deleteHighlight(pageno, item)
@@ -237,6 +255,7 @@ function PdfDocument:deleteHighlight(pageno, item)
     local annot = page:getMarkupAnnotation(quadpoints, n)
     if annot ~= nil then
         page:deleteMarkupAnnotation(annot)
+        self:resetTileCacheValidity()
     end
     page:close()
 end
@@ -251,6 +270,7 @@ function PdfDocument:updateHighlightContents(pageno, item, contents)
     local annot = page:getMarkupAnnotation(quadpoints, n)
     if annot ~= nil then
         page:updateMarkupAnnotation(annot, contents)
+        self:resetTileCacheValidity()
     end
     page:close()
 end

frontend/document/tilecacheitem.lua

@@ -17,6 +17,7 @@ function TileCacheItem:totable()
         size = self.size,
         pageno = self.pageno,
         excerpt = self.excerpt,
+        created_ts = self.created_ts,
         persistent = self.persistent,
         bb = {
             w = self.bb.w,
@@ -51,6 +52,7 @@ function TileCacheItem:fromtable(t)
     self.size = t.size
     self.pageno = t.pageno
     self.excerpt = t.excerpt
+    self.created_ts = t.created_ts
     self.persistent = t.persistent
     self.bb = Blitbuffer.fromstring(t.bb.w, t.bb.h, t.bb.fmt, t.bb.data, t.bb.stride)
 end