implement 'current article' property of the application

Also, fix the unique-id based accessors (the four byte code  for id was
wrong in the sdef)
Add valueIn<Key>WithUniqueID accessors
Add a few protocols and protocol implementations for the AppDelegate
and MainWindowControllor so as to expose needed functionality for
scriptability

Evergreen/Scriptability/Account+Scriptability.swift

@@ -54,12 +54,29 @@ class ScriptableAccount: NSObject, UniqueIdScriptingObject, ScriptingObjectConta
         return feeds.map { ScriptableFeed($0, container:self) } as NSArray
     }
     
+    @objc(valueInFeedsWithUniqueID:)
+    func valueInFeeds(withUniqueID id:String) -> ScriptableFeed? {
+        let feeds = account.children.compactMap { $0 as? Feed }
+        guard let feed = feeds.first(where:{$0.feedID == id}) else { return nil }
+        return ScriptableFeed(feed, container:self)
+    }
+    
+
     @objc(folders)
     var folders:NSArray  {
         let folders = account.children.compactMap { $0 as? Folder }
         return folders.map { ScriptableFolder($0, container:self) } as NSArray
     }
     
+    @objc(valueInFoldersWithUniqueID:)
+    func valueInFolders(withUniqueID id:NSNumber) -> ScriptableFolder? {
+        let folderId = id.intValue
+        let folders = account.children.compactMap { $0 as? Folder }
+        guard let folder = folders.first(where:{$0.folderID == folderId}) else { return nil }
+        return ScriptableFolder(folder, container:self)
+    }
+    
+
     // MARK: --- Scriptable properties ---
 
     @objc(contents)

Evergreen/Scriptability/AppDelegate+Scriptability.swift

@@ -0,0 +1,28 @@
+//
+//  AppDelegate+Scriptability.swift
+//  Evergreen
+//
+//  Created by Olof Hellman on 2/7/18.
+//  Copyright © 2018 Ranchero Software. All rights reserved.
+//
+
+/*
+    Note:  strictly, the AppDelegate doesn't appear as part of the scripting model,
+    so this file is rather unlike the other Object+Scriptability.swift files.
+    However, the AppDelegate object is the de facto scripting accessor for some
+    application elements and properties.  For, example, the main window is accessed
+    via the AppDelegate's MainWindowController, and the main window itself has
+    selected feeds, selected articles and a current article.  This file supplies the glue to access
+    these scriptable objects, while being completely separate from the core AppDelegate code,
+*/
+
+import Foundation
+import Data
+
+protocol ScriptingAppDelegate {
+    var  scriptingCurrentArticle: Article?  {get}
+    var  scriptingSelectedArticles: [Article]  {get}
+    var  scriptingMainWindowController:ScriptingMainWindowController? {get}
+}
+
+

Evergreen/Scriptability/Feed+Scriptability.swift

@@ -85,11 +85,19 @@ class ScriptableFeed: NSObject, UniqueIdScriptingObject, ScriptingObjectContaine
         return self.feed.OPMLString(indentLevel:0)
     }
     
+    // MARK: --- scriptable elements ---
+
     @objc(authors)
     var authors:NSArray {
         let feedAuthors = feed.authors ?? []
         return feedAuthors.map { ScriptableAuthor($0, container:self) } as NSArray
     }
+     
+    @objc(valueInAuthorsWithUniqueID:)
+    func valueInAuthors(withUniqueID id:String) -> ScriptableAuthor? {
+        guard let author = feed.authors?.first(where:{$0.authorID == id}) else { return nil }
+        return ScriptableAuthor(author, container:self)
+    }
     
     @objc(articles)
     var articles:NSArray {
@@ -100,5 +108,12 @@ class ScriptableFeed: NSObject, UniqueIdScriptingObject, ScriptingObjectContaine
         })
         return sortedArticles.map { ScriptableArticle($0, container:self) } as NSArray
     }
+    
+    @objc(valueInArticlesWithUniqueID:)
+    func valueInArticles(withUniqueID id:String) -> ScriptableArticle? {
+        let articles = feed.fetchArticles()
+        guard let article = articles.first(where:{$0.uniqueID == id}) else { return nil }
+        return ScriptableArticle(article, container:self)
+    }
 
 }

Evergreen/Scriptability/MainWindowController+Scriptability.swift

@@ -0,0 +1,16 @@
+//
+//  MainWindowController+Scriptability.swift
+//  Evergreen
+//
+//  Created by Olof Hellman on 2/7/18.
+//  Copyright © 2018 Ranchero Software. All rights reserved.
+//
+
+import Foundation
+import Data
+
+protocol ScriptingMainWindowController {
+    var scriptingCurrentArticle: Article? { get }
+    var scriptingSelectedArticles: [Article] { get }
+}
+

Evergreen/Scriptability/NSApplication+Scriptability.swift

@@ -20,27 +20,74 @@ extension NSApplication : ScriptingObjectContainer {
         return "application"
     }
     
+    @objc(currentArticle)
+    func currentArticle() -> ScriptableArticle? {
+        var scriptableArticle: ScriptableArticle?
+        if let currentArticle = appDelegate.scriptingCurrentArticle {
+            if let feed = currentArticle.feed {
+                let scriptableFeed = ScriptableFeed(feed, container:self)
+                scriptableArticle = ScriptableArticle(currentArticle, container:scriptableFeed)
+            }
+        }
+        return scriptableArticle
+    }
+
+    @objc(selectedArticles)
+    func selectedArticles() -> NSArray {
+        let articles = appDelegate.scriptingSelectedArticles
+        let scriptableArticles:[ScriptableArticle] = articles.compactMap { article in
+            if let feed = article.feed  {
+                let scriptableFeed = ScriptableFeed(feed, container:self)
+                return ScriptableArticle(article, container:scriptableFeed)
+            } else {
+                return nil
+            }
+        }
+        return scriptableArticles as NSArray
+    }
+
+    // MARK: --- scriptable elements ---
+
     @objc(accounts)
     func accounts() -> NSArray {
         let accounts = AccountManager.shared.accounts
         return accounts.map { ScriptableAccount($0) } as NSArray
     }
     
+    @objc(valueInAccountsWithUniqueID:)
+    func valueInAccounts(withUniqueID id:String) -> ScriptableAccount? {
+        let accounts = AccountManager.shared.accounts
+        guard let account = accounts.first(where:{$0.accountID == id}) else { return nil }
+        return ScriptableAccount(account)
+    }
+
     /*
         accessing feeds from the application object skips the 'account' containment hierarchy
         this allows a script like 'articles of feed "The Shape of Everything"' as a shorthand
         for  'articles of feed "The Shape of Everything" of account "On My Mac"'
-    */
-    @objc(feeds)
-    func feeds() -> NSArray {
+    */  
+      
+    func allFeeds() -> [Feed] {
         let accounts = AccountManager.shared.accounts
         let emptyFeeds:[Feed] = []
-        let feeds = accounts.reduce(emptyFeeds) { (result, nthAccount) -> [Feed] in
+        return accounts.reduce(emptyFeeds) { (result, nthAccount) -> [Feed] in
               let accountFeeds = nthAccount.children.compactMap { $0 as? Feed }
               return result + accountFeeds
         }
+    }
+
+    @objc(feeds)
+    func feeds() -> NSArray {
+        let feeds = self.allFeeds()
         return feeds.map { ScriptableFeed($0, container:self) } as NSArray
     }
+
+    @objc(valueInFeedsWithUniqueID:)
+    func valueInFeeds(withUniqueID id:String) -> ScriptableFeed? {
+        let feeds = self.allFeeds()
+        guard let feed = feeds.first(where:{$0.feedID == id}) else { return nil }
+        return ScriptableFeed(feed, container:self)
+    }
 }