[geary/mjog/email-plugins: 60/61] Plugin.FolderStore: Add new list_containing_folders method

[Michael Gratton <mjog src gnome org>]

commit d81393458a21d3a89957bd6f9e39befcd39b07f3
Author: Michael Gratton <mike vee net>
Date:   Mon Mar 23 00:05:53 2020 +1100

    Plugin.FolderStore: Add new list_containing_folders method
    
    Adds new abstract method and implementation.

 .../application-email-store-factory.vala           | 11 ++++----
 .../application-folder-store-factory.vala          | 31 ++++++++++++++++++++--
 src/client/plugin/plugin-folder-store.vala         |  6 +++++
 3 files changed, 41 insertions(+), 7 deletions(-)
---
diff --git a/src/client/application/application-email-store-factory.vala 
b/src/client/application/application-email-store-factory.vala
index 7d7c94f1..fe391320 100644
--- a/src/client/application/application-email-store-factory.vala
+++ b/src/client/application/application-email-store-factory.vala
@@ -88,7 +88,8 @@ internal class Application.EmailStoreFactory : Geary.BaseObject {
     }
 
 
-    private class EmailImpl : Geary.BaseObject, Plugin.Email {
+    /** Implementation of the plugin email interface. */
+    internal class EmailImpl : Geary.BaseObject, Plugin.Email {
 
 
         public Plugin.EmailIdentifier identifier {
@@ -116,7 +117,7 @@ internal class Application.EmailStoreFactory : Geary.BaseObject {
         internal Geary.AccountInformation account { get; private set; }
 
 
-        public EmailImpl(Geary.Email backing,
+        internal EmailImpl(Geary.Email backing,
                          Geary.AccountInformation account) {
             this.backing = backing;
             this.account = account;
@@ -131,7 +132,7 @@ internal class Application.EmailStoreFactory : Geary.BaseObject {
     }
 
 
-    private class IdImpl : Geary.BaseObject,
+    internal class IdImpl : Geary.BaseObject,
         Gee.Hashable<Plugin.EmailIdentifier>, Plugin.EmailIdentifier {
 
 
@@ -141,8 +142,8 @@ internal class Application.EmailStoreFactory : Geary.BaseObject {
         internal Geary.AccountInformation account { get; private set; }
 
 
-        public IdImpl(Geary.EmailIdentifier backing,
-                      Geary.AccountInformation account) {
+        internal IdImpl(Geary.EmailIdentifier backing,
+                        Geary.AccountInformation account) {
             this.backing = backing;
             this.account = account;
         }
diff --git a/src/client/application/application-folder-store-factory.vala 
b/src/client/application/application-folder-store-factory.vala
index a419eaee..f69d91fd 100644
--- a/src/client/application/application-folder-store-factory.vala
+++ b/src/client/application/application-folder-store-factory.vala
@@ -24,10 +24,13 @@ internal class Application.FolderStoreFactory : Geary.BaseObject {
             "(sv)"
         );
 
+        private Client application;
         private Gee.Map<Geary.Folder,FolderImpl> folders;
 
 
-        public FolderStoreImpl(Gee.Map<Geary.Folder,FolderImpl> folders) {
+        public FolderStoreImpl(Client application,
+                               Gee.Map<Geary.Folder,FolderImpl> folders) {
+            this.application = application;
             this.folders = folders;
         }
 
@@ -35,6 +38,30 @@ internal class Application.FolderStoreFactory : Geary.BaseObject {
             return this.folders.values.read_only_view;
         }
 
+        public async Gee.Collection<Plugin.Folder> list_containing_folders(
+            Plugin.EmailIdentifier target,
+            GLib.Cancellable? cancellable
+        ) throws GLib.Error {
+            var id = target as EmailStoreFactory.IdImpl;
+            var folders = new Gee.LinkedList<Plugin.Folder>();
+            AccountContext context =
+                this.application.controller.get_context_for_account(id.account);
+            if (id != null && context != null) {
+                Gee.MultiMap<Geary.EmailIdentifier,Geary.FolderPath>? multi_folders =
+                    yield context.account.get_containing_folders_async(
+                        Geary.Collection.single(id.backing),
+                        cancellable
+                    );
+                if (multi_folders != null) {
+                    foreach (var path in multi_folders.get(id.backing)) {
+                        var folder = context.account.get_folder(path);
+                        folders.add(this.folders.get(folder));
+                    }
+                }
+            }
+            return folders;
+        }
+
         public Plugin.Folder? get_folder_from_variant(GLib.Variant variant) {
             Plugin.Folder? found = null;
             // XXX this is pretty inefficient
@@ -176,7 +203,7 @@ internal class Application.FolderStoreFactory : Geary.BaseObject {
 
     /** Constructs a new folder store for use by plugin contexts. */
     public Plugin.FolderStore new_folder_store() {
-        var store = new FolderStoreImpl(this.folders);
+        var store = new FolderStoreImpl(this.application, this.folders);
         this.stores.add(store);
         return store;
     }
diff --git a/src/client/plugin/plugin-folder-store.vala b/src/client/plugin/plugin-folder-store.vala
index 3cc8b977..08a05c5f 100644
--- a/src/client/plugin/plugin-folder-store.vala
+++ b/src/client/plugin/plugin-folder-store.vala
@@ -39,6 +39,12 @@ public interface Plugin.FolderStore : Geary.BaseObject {
     /** Returns a read-only set of all known folders. */
     public abstract Gee.Collection<Folder> get_folders();
 
+    /** Returns the set of folders that contains the given email. */
+    public abstract async Gee.Collection<Folder> list_containing_folders(
+        EmailIdentifier target,
+        GLib.Cancellable? cancellable
+    ) throws GLib.Error;
+
     /**
      * Returns the folder specified by the given identifier, if any.
      *