/*
 * DependentListStore.cs
 *
 * Author(s)
 *   Gabriel Burt  <gabriel.burt@gmail.com>
 *
 * This is free software. See COPYING for details.
 */

using Gtk;
using Gdk;
using System;

public class DependentListStore : ListStore {
        private TreeModel parent = null;

        public TreeModel Parent {
                get { return parent; }
                set {
                        if (parent != null) {
                                parent.RowInserted -= HandleInserted;
                                parent.RowDeleted -= HandleDeleted;
                                parent.RowChanged -= HandleChanged;
                        }

                        parent = value;

                        GLib.GType [] types = new GLib.GType[parent.NColumns];
                        for(int i = 0; i < parent.NColumns; i++) {
                                types[i] = parent.GetColumnType(i);
                        }

                        this.ColumnTypes = types;

                        Copy(parent, this);

                        // Listen to the parent to mimick its changes
                        parent.RowInserted += HandleInserted;
                        parent.RowDeleted += HandleDeleted;
                        parent.RowChanged += HandleChanged;
                }
        }

        public DependentListStore(TreeModel tree_model) {
                Parent = tree_model;
        }

        /* FIXME: triggering a recopy of the parent doesn't seem to be enough to
         * get the updated values from it -- at least in the particular case of F-Spot's tag selection widget's model */
        private void HandleInserted(object sender, RowInsertedArgs args)
        {
                QueueUpdate();
        }

        private void HandleDeleted(object sender, RowDeletedArgs args)
        {
                QueueUpdate();
        }

        private void HandleChanged(object sender, RowChangedArgs args)
        {
                QueueUpdate();
        }

        private uint timeout_id = 0;
        private void QueueUpdate()
        {
                if (timeout_id != 0)
                        GLib.Source.Remove(timeout_id);

                timeout_id = GLib.Timeout.Add(1000, OnUpdateTimer);
        }

        private bool OnUpdateTimer()
        {
                timeout_id = 0;
                Copy(Parent, this);
                return false;
        }

        public static void Copy(TreeModel tree, ListStore list)
        {
                list.Clear();

                TreeIter tree_iter;
                if (tree.IterChildren(out tree_iter)) {
                        Copy(tree, tree_iter, list, true);
                }
        }

        public static void Copy(TreeModel tree, TreeIter tree_iter, ListStore list, bool first)
        {
                // Copy this iter's values to the list
                TreeIter list_iter = list.Append();
                for (int i = 0; i < list.NColumns; i++) {
                        list.SetValue(list_iter, i, tree.GetValue(tree_iter, i));
                        if (i == 1) {
                                //Console.WriteLine("Copying {0}", list.GetValue(list_iter, i));
                        }
                }

                // Copy the first child, which will trigger the copy if its siblings (and their children)
                TreeIter child_iter;
                if (tree.IterChildren(out child_iter, tree_iter)) {
                        Copy(tree, child_iter, list, true);
                }

                // Add siblings and their children if we are the first child, otherwise doing so would repeat
                if (first) {
                        while (tree.IterNext(ref tree_iter)) {
                                Copy(tree, tree_iter, list, false);
                        }
                }
        }
}