[geary: 10/11] Update monitoring for new mail when folder special type changes.

[Michael Gratton <mjog src gnome org>]

commit de0618e6062e9ed904601b551c97f23641feeda9
Author: Michael James Gratton <mike vee net>
Date:   Sat Jan 27 16:22:45 2018 +1030

    Update monitoring for new mail when folder special type changes.
    
    Followup to commit 9727d41 for Bug 713227.
    
    * src/client/application/geary-controller.vala (Controller): Break out
      the check to determine if a folder is a child of the inbox, simplify
      and make more robust. Use that to check both available folders and
      folders whose special type has changed.
    
    * src/engine/api/geary-folder-path.vala (FolderPath): Add new
      is_descendent method.

 src/client/application/geary-controller.vala |   87 +++++++++++++++++---------
 src/engine/api/geary-folder-path.vala        |   16 +++++
 2 files changed, 73 insertions(+), 30 deletions(-)
---
diff --git a/src/client/application/geary-controller.vala b/src/client/application/geary-controller.vala
index 1ba87c1..0fc0a35 100644
--- a/src/client/application/geary-controller.vala
+++ b/src/client/application/geary-controller.vala
@@ -1,6 +1,6 @@
 /*
  * Copyright 2016 Software Freedom Conservancy Inc.
- * Copyright 2016, 2017 Michael Gratton <mike vee net>
+ * Copyright 2016-2018 Michael Gratton <mike vee net>
  *
  * This software is licensed under the GNU Lesser General Public License
  * (version 2.1 or later). See the COPYING file in this distribution.
@@ -1227,6 +1227,23 @@ public class GearyController : Geary.BaseObject {
         return num;
     }
 
+    private bool is_inbox_descendant(Geary.Folder target) {
+        bool is_descendent = false;
+
+        Geary.Account account = target.account;
+        Geary.Folder? inbox = null;
+        try {
+            inbox = account.get_special_folder(Geary.SpecialFolderType.INBOX);
+        } catch (Error err) {
+            debug("Failed to get inbox for account %s", account.information.id);
+        }
+
+        if (inbox != null) {
+            is_descendent = inbox.path.is_descendant(target.path);
+        }
+        return is_descendent;
+    }
+
     // Update widgets and such to match capabilities of the current folder ... sensitivity is handled
     // by other utility methods
     private void update_ui() {
@@ -1506,12 +1523,23 @@ public class GearyController : Geary.BaseObject {
         );
     }
 
-    private void on_special_folder_type_changed(Geary.Folder folder, Geary.SpecialFolderType old_type,
-        Geary.SpecialFolderType new_type) {
-        main_window.folder_list.remove_folder(folder);
-        main_window.folder_list.add_folder(folder);
+    private void on_special_folder_type_changed(Geary.Folder folder,
+                                                Geary.SpecialFolderType old_type,
+                                                Geary.SpecialFolderType new_type) {
+        // Update the main window
+        this.main_window.folder_list.remove_folder(folder);
+        this.main_window.folder_list.add_folder(folder);
+
+        // Update notifications
+        this.new_messages_monitor.remove_folder(folder);
+        if (folder.special_folder_type == Geary.SpecialFolderType.INBOX ||
+            (folder.special_folder_type == Geary.SpecialFolderType.NONE &&
+             is_inbox_descendant(folder))) {
+            GLib.Cancellable cancellable = this.inbox_cancellables.get(folder.account);
+            this.new_messages_monitor.add_folder(folder, cancellable);
+        }
     }
-    
+
     private void on_engine_opened() {
         // Locate the first account so we can select its inbox when available.
         try {
@@ -1555,35 +1583,34 @@ public class GearyController : Geary.BaseObject {
                     if (!main_window.main_toolbar.move_folder_menu.has_folder(folder))
                         main_window.main_toolbar.move_folder_menu.add_folder(folder);
                 }
-                
-                // monitor the Inbox for notifications
-                if (folder.special_folder_type == Geary.SpecialFolderType.INBOX &&
-                    !inboxes.has_key(folder.account)) {
-                    inboxes.set(folder.account, folder);
-                    Geary.Folder? select_folder = get_initial_selection_folder(folder);
-                    
-                    if (select_folder != null) {
-                        // First we try to select the Inboxes branch inbox if
-                        // it's there, falling back to the main folder list.
-                        if (!main_window.folder_list.select_inbox(select_folder.account))
-                            main_window.folder_list.select_folder(select_folder);
-                    }
 
-                    GLib.Cancellable cancellable = inbox_cancellables.get(folder.account);
-                    folder.open_async.begin(Geary.Folder.OpenFlags.NO_DELAY, cancellable);
+                GLib.Cancellable cancellable = this.inbox_cancellables.get(folder.account);
 
-                    new_messages_monitor.add_folder(folder, cancellable);
+                switch (folder.special_folder_type) {
+                case Geary.SpecialFolderType.INBOX:
+                    // Special case handling of inboxes
+                    if (!inboxes.has_key(folder.account)) {
+                        inboxes.set(folder.account, folder);
 
-                    // also monitor Inbox's children for notifications
-                    try {
-                        foreach (Geary.Folder children in account.list_matching_folders(folder.path)) {
-                            if (children.special_folder_type == Geary.SpecialFolderType.NONE) {
-                                new_messages_monitor.add_folder(children, cancellable);
-                            }
+                        Geary.Folder? select_folder = get_initial_selection_folder(folder);
+                        if (select_folder != null) {
+                            // First we try to select the Inboxes branch inbox if
+                            // it's there, falling back to the main folder list.
+                            if (!main_window.folder_list.select_inbox(select_folder.account))
+                                main_window.folder_list.select_folder(select_folder);
                         }
-                    } catch (Error e) {
-                        debug("Could not retrieve Inbox children: %s", e.message);
                     }
+
+                    folder.open_async.begin(Geary.Folder.OpenFlags.NO_DELAY, cancellable);
+
+                    // Always notify for new messages in the Inbox
+                    break;
+                    
+                case Geary.SpecialFolderType.NONE:
+                    if (is_inbox_descendant(folder)) {
+                        this.new_messages_monitor.add_folder(folder, cancellable);
+                    }
+                    break;
                 }
                 
                 folder.special_folder_type_changed.connect(on_special_folder_type_changed);
diff --git a/src/engine/api/geary-folder-path.vala b/src/engine/api/geary-folder-path.vala
index b118be2..5193a63 100644
--- a/src/engine/api/geary-folder-path.vala
+++ b/src/engine/api/geary-folder-path.vala
@@ -164,6 +164,22 @@ public class Geary.FolderPath : BaseObject, Gee.Hashable<Geary.FolderPath>,
         return false;
     }
 
+    /**
+     * Determines if this path is a strict ancestor of another.
+     */
+    public bool is_descendant(FolderPath target) {
+        bool is_descendent = false;
+        Geary.FolderPath? path = target.get_parent();
+        while (path != null) {
+            if (path.equal_to(this)) {
+                is_descendent = true;
+                break;
+            }
+            path = path.get_parent();
+        }
+        return is_descendent;
+    }
+
     private uint get_basename_hash() {
         return case_sensitive ? str_hash(basename) : str_hash(basename.down());
     }