/* -*- Mode: C; coding: utf-8; indent-tabs-mode: nil; tab-width: 2 -*-

A dialog for setting time and date preferences.

Copyright 2011 Canonical Ltd.

Authors:
    Michael Terry <michael.terry@canonical.com>

This program is free software: you can redistribute it and/or modify it 
under the terms of the GNU General Public License version 3, as published 
by the Free Software Foundation.

This program is distributed in the hope that it will be useful, but 
WITHOUT ANY WARRANTY; without even the implied warranties of 
MERCHANTABILITY, SATISFACTORY QUALITY, or FITNESS FOR A PARTICULAR 
PURPOSE.  See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along 
with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdlib.h>
#include <glib/gi18n-lib.h>
#include <gtk/gtk.h>

#include "datetime-prefs-locations.h"
#include "settings-shared.h"
#include "utils.h"
#include "timezone-completion.h"

#define DATETIME_DIALOG_UI_FILE PKGDATADIR "/datetime-dialog.ui"

#define COL_NAME         0
#define COL_TIME         1
#define COL_ZONE         2
#define COL_VISIBLE_NAME 3
#define COL_ICON         4

static gboolean update_times (GtkWidget * dlg);
static void save_when_idle (GtkWidget * dlg);

static void
handle_add (GtkWidget * button, GtkTreeView * tree)
{
  GtkListStore * store = GTK_LIST_STORE (gtk_tree_view_get_model (tree));

  GtkTreeIter iter;
  gtk_list_store_append (store, &iter);

  GtkTreePath * path = gtk_tree_model_get_path (GTK_TREE_MODEL (store), &iter);
  gtk_tree_view_set_cursor (tree, path, gtk_tree_view_get_column (tree, 0), TRUE);
  gtk_tree_path_free (path);
}

static void
handle_remove (GtkWidget * button, GtkTreeView * tree)
{
  GtkListStore * store = GTK_LIST_STORE (gtk_tree_view_get_model (tree));
  GtkTreeSelection * selection = gtk_tree_view_get_selection (tree);

  GList * paths = gtk_tree_selection_get_selected_rows (selection, NULL);

  /* Convert all paths to iters so we can safely delete multiple paths.  For a
     GtkListStore, iters persist past model changes. */
  GList * tree_iters = NULL;
  GList * iter;
  for (iter = paths; iter; iter = iter->next) {
    GtkTreeIter * tree_iter = g_new(GtkTreeIter, 1);
    if (gtk_tree_model_get_iter (GTK_TREE_MODEL (store), tree_iter, (GtkTreePath *)iter->data)) {
      tree_iters = g_list_prepend (tree_iters, tree_iter);
    }
    gtk_tree_path_free (iter->data);
  }
  g_list_free (paths);
  
  // Find the next item to select
  GtkTreeIter *last_selected = g_list_nth_data(tree_iters, 0);
  GtkTreePath *path = gtk_tree_model_get_path(GTK_TREE_MODEL (store), last_selected);
  GtkTreeIter titer;
  if (!gtk_tree_model_get_iter(GTK_TREE_MODEL (store), &titer, path)) {
    g_debug("Failed to get last selected iter from path");
  	last_selected = NULL;
  } else {
	  if (!gtk_tree_model_iter_next(GTK_TREE_MODEL (store), &titer)) {
	  	if (gtk_tree_path_prev(path)) {
	  	  	if (!gtk_tree_model_get_iter(GTK_TREE_MODEL (store), &titer, path)) {
	  			g_debug("Failed to get iter from path");
	  			last_selected = NULL;
	  		} else {
		  		last_selected = &titer;
		  	}
	  	} else {
	  		g_debug("handle_remove: Failed to find another location to select (assume single selected)");
	  		last_selected = NULL;
	  	}
	  } else {
	  	g_debug("Got next item in model");
		last_selected = &titer;
	  }
  }
 
  if (last_selected) {
	  gboolean clear = TRUE;
	  path = gtk_tree_model_get_path(GTK_TREE_MODEL (store), last_selected);
	  
      // Step over the path to find an item which isn't in the delete list
	  if (g_list_length(tree_iters) > 1) {
		  for (iter = tree_iters; iter; iter = iter->next) {
		  	GtkTreePath *ipath = gtk_tree_model_get_path(GTK_TREE_MODEL (store), (GtkTreeIter *)iter->data);
		  	if (gtk_tree_path_compare(path, ipath) == 0) {
		  		clear = FALSE;
		  		break;
		  	}
		  }
	  	  while (clear == FALSE) {
			if (gtk_tree_path_prev(path)) {
				clear = TRUE;
		  	  	for (iter = tree_iters; iter; iter = iter->next) {
		  			GtkTreePath *ipath = gtk_tree_model_get_path(GTK_TREE_MODEL (store), (GtkTreeIter *)iter->data);
		  			if (gtk_tree_path_compare(path, ipath) == 0) {
		  				clear = FALSE;
		  				break;
		  			}
		  		}
		  		if (clear) {
			  		if (!gtk_tree_model_get_iter(GTK_TREE_MODEL (store), &titer, path)) {
			  			g_debug("Failed to get iter from path");
			  			last_selected = NULL;
			  		} else {
				  		last_selected = &titer;
				  	}
				}
		  	} else {
		  		last_selected = NULL;
		  		break;
		  	}
		  }
	  }
  }
  
  /* Now delete each iterator */
  for (iter = tree_iters; iter; iter = iter->next) {
    gtk_list_store_remove (store, (GtkTreeIter *)iter->data);
    g_free (iter->data);
  }
  g_list_free (tree_iters);
  
  if (last_selected)
	  gtk_tree_selection_select_iter(selection, last_selected);
}

static void
handle_edit (GtkCellRendererText * renderer, gchar * path, gchar * new_text,
             GtkListStore * store)
{
  GtkTreeIter iter;

  // Manual user edits are always wrong (unless they are undoing a previous
  // edit), so we set the error icon here if needed.  Common way to get to
  // this code path is to lose entry focus.
  if (gtk_tree_model_get_iter_from_string (GTK_TREE_MODEL (store), &iter, path)) {
    const gchar * name;
    gtk_tree_model_get (GTK_TREE_MODEL (store), &iter, COL_NAME, &name, -1);
    gboolean correct = g_strcmp0 (name, new_text) == 0;

    gtk_list_store_set (store, &iter,
                        COL_VISIBLE_NAME, new_text,
                        COL_ICON, correct ? NULL : GTK_STOCK_DIALOG_ERROR,
                        -1);
  }
}

static gboolean
timezone_selected (GtkEntryCompletion * widget, GtkTreeModel * model,
                   GtkTreeIter * iter, GtkWidget * dlg)
{
  const gchar * zone, * name;

  gtk_tree_model_get (model, iter,
                      TIMEZONE_COMPLETION_ZONE, &zone,
                      TIMEZONE_COMPLETION_NAME, &name,
                      -1);

  if (zone == NULL || zone[0] == 0) {
    const gchar * strlon, * strlat;
    gdouble lon = 0.0, lat = 0.0;

    gtk_tree_model_get (model, iter,
                        TIMEZONE_COMPLETION_LONGITUDE, &strlon,
                        TIMEZONE_COMPLETION_LATITUDE, &strlat,
                        -1);

    if (strlon != NULL && strlon[0] != 0) {
      lon = strtod(strlon, NULL);
    }

    if (strlat != NULL && strlat[0] != 0) {
      lat = strtod(strlat, NULL);
    }

    CcTimezoneMap * tzmap = CC_TIMEZONE_MAP (g_object_get_data (G_OBJECT (widget), "tzmap"));
    zone = cc_timezone_map_get_timezone_at_coords (tzmap, lon, lat);
  }

  GtkListStore * store = GTK_LIST_STORE (g_object_get_data (G_OBJECT (widget), "store"));
  GtkTreeIter * store_iter = (GtkTreeIter *)g_object_get_data (G_OBJECT (widget), "store_iter");
  if (store != NULL && store_iter != NULL) {
    gtk_list_store_set (store, store_iter,
                        COL_VISIBLE_NAME, name,
                        COL_ICON, NULL,
                        COL_NAME, name,
                        COL_ZONE, zone, -1);
  }

  update_times (dlg);

  return FALSE; // Do normal action too
}

static gboolean
query_tooltip (GtkTreeView * tree, gint x, gint y, gboolean keyboard_mode,
               GtkTooltip * tooltip, GtkCellRenderer * cell)
{
  GtkTreeModel * model;
  GtkTreeIter iter;
  if (!gtk_tree_view_get_tooltip_context (tree, &x, &y, keyboard_mode,
                                          &model, NULL, &iter))
    return FALSE;

  const gchar * icon;
  gtk_tree_model_get (model, &iter, COL_ICON, &icon, -1);
  if (icon == NULL)
    return FALSE;

  GtkTreeViewColumn * col = gtk_tree_view_get_column (tree, 0);
  gtk_tree_view_set_tooltip_cell (tree, tooltip, NULL, col, cell);
  gtk_tooltip_set_text (tooltip, _("You need to complete this location for it to appear in the menu."));
  return TRUE;
}

static void
handle_edit_started (GtkCellRendererText * renderer, GtkCellEditable * editable,
                     gchar * path, TimezoneCompletion * completion)
{
  if (GTK_IS_ENTRY (editable)) {
    GtkEntry *entry = GTK_ENTRY (editable);
    timezone_completion_watch_entry (completion, entry);

    GtkListStore * store = GTK_LIST_STORE (g_object_get_data (G_OBJECT (completion), "store"));
    GtkTreeIter * store_iter = g_new(GtkTreeIter, 1);
    if (gtk_tree_model_get_iter_from_string (GTK_TREE_MODEL (store), store_iter, path)) {
      g_object_set_data_full (G_OBJECT (completion), "store_iter", store_iter, g_free);
    }
  }
}

static gboolean
update_times (GtkWidget * dlg)
{
  /* For each entry, check zone in column 2 and set column 1 to it's time */
  TimezoneCompletion * completion = TIMEZONE_COMPLETION (g_object_get_data (G_OBJECT (dlg), "completion"));
  GtkListStore * store = GTK_LIST_STORE (g_object_get_data (G_OBJECT (completion), "store"));
  GObject * cell = G_OBJECT (g_object_get_data (G_OBJECT (completion), "name-cell"));

  gboolean editing;
  g_object_get (cell, "editing", &editing, NULL);
  if (editing) { /* No updates while editing, it cancels the edit */
    return TRUE;
  }

  g_signal_handlers_block_by_func (store, save_when_idle, dlg);

  GDateTime * now = g_date_time_new_now_local ();

  GtkTreeIter iter;
  if (gtk_tree_model_get_iter_first (GTK_TREE_MODEL (store), &iter)) {
    do {
      const gchar * strzone;

      gtk_tree_model_get (GTK_TREE_MODEL (store), &iter, COL_ZONE, &strzone, -1);

      if (strzone != NULL && strzone[0] != 0) {
        GTimeZone * tz = g_time_zone_new (strzone);
        GDateTime * now_tz = g_date_time_to_timezone (now, tz);
        gchar * format = generate_format_string_at_time (now_tz);
        gchar * time_str = g_date_time_format (now_tz, format);

        gtk_list_store_set (store, &iter, COL_TIME, time_str, -1);

        g_free (time_str);
        g_free (format);
        g_date_time_unref (now_tz);
        g_time_zone_unref (tz);
      }
    } while (gtk_tree_model_iter_next (GTK_TREE_MODEL (store), &iter));
  }

  g_date_time_unref (now);

  g_signal_handlers_unblock_by_func (store, save_when_idle, dlg);

  return TRUE;
}

static void
fill_from_settings (GObject * store, GSettings * conf)
{
  gchar ** locations = g_settings_get_strv (conf, SETTINGS_LOCATIONS_S);

  gtk_list_store_clear (GTK_LIST_STORE (store));

  gchar ** striter;
  GtkTreeIter iter;
  for (striter = locations; *striter; ++striter) {
    gchar * zone, * name;
    split_settings_location (*striter, &zone, &name);

    gtk_list_store_append (GTK_LIST_STORE (store), &iter);
    gtk_list_store_set (GTK_LIST_STORE (store), &iter,
                        COL_VISIBLE_NAME, name,
                        COL_ICON, NULL,
                        COL_NAME, name,
                        COL_ZONE, zone, -1);

    g_free (zone);
    g_free (name);
  }

  g_strfreev (locations);
}

static void
save_to_settings (GObject * store, GSettings * conf)
{
  gboolean empty = TRUE;
  GVariantBuilder builder;
  g_variant_builder_init (&builder, G_VARIANT_TYPE_ARRAY);

  GtkTreeIter iter;
  if (gtk_tree_model_get_iter_first (GTK_TREE_MODEL (store), &iter)) {
    do {
      const gchar * strzone, * strname;

      gtk_tree_model_get (GTK_TREE_MODEL (store), &iter,
                          COL_NAME, &strname,
                          COL_ZONE, &strzone,
                          -1);

      if (strzone != NULL && strzone[0] != 0 && strname != NULL && strname[0] != 0) {
        gchar * settings_string = g_strdup_printf("%s %s", strzone, strname);
        g_variant_builder_add (&builder, "s", settings_string);
        g_free (settings_string);
        empty = FALSE;
      }
    } while (gtk_tree_model_iter_next (GTK_TREE_MODEL (store), &iter));
  }

  if (empty) {
    /* Empty list */
    g_variant_builder_clear (&builder);
    g_settings_set_strv (conf, SETTINGS_LOCATIONS_S, NULL);
  }
  else {
    GVariant * locations = g_variant_builder_end (&builder);
    g_settings_set_strv (conf, SETTINGS_LOCATIONS_S, g_variant_get_strv (locations, NULL));
    g_variant_unref (locations);
  }
}

static gboolean
save_now (GtkWidget *dlg)
{
  GSettings * conf = G_SETTINGS (g_object_get_data (G_OBJECT (dlg), "conf"));
  GObject * completion = G_OBJECT (g_object_get_data (G_OBJECT (dlg), "completion"));
  GObject * store = G_OBJECT (g_object_get_data (completion, "store"));

  save_to_settings (store, conf);

  g_object_set_data (G_OBJECT (dlg), "save-id", GINT_TO_POINTER(0));

  return FALSE;
}

static void
save_when_idle (GtkWidget *dlg)
{
  guint save_id = GPOINTER_TO_INT (g_object_get_data (G_OBJECT (dlg), "save-id"));

  if (save_id == 0) {
    save_id = g_idle_add ((GSourceFunc)save_now, dlg);
    g_object_set_data (G_OBJECT (dlg), "save-id", GINT_TO_POINTER(save_id));
  }
}

static void
dialog_closed (GtkWidget * dlg, GObject * store)
{
  /* Cleanup a tad */
  guint time_id = GPOINTER_TO_INT (g_object_get_data (G_OBJECT (dlg), "time-id"));
  g_source_remove (time_id);

  guint save_id = GPOINTER_TO_INT (g_object_get_data (G_OBJECT (dlg), "save-id"));
  if (save_id > 0)
    g_source_remove (save_id);
}

static void
selection_changed (GtkTreeSelection * selection, GtkWidget * remove_button)
{
  gint count = gtk_tree_selection_count_selected_rows (selection);
  gtk_widget_set_sensitive (remove_button, count > 0);
}

GtkWidget *
datetime_setup_locations_dialog (CcTimezoneMap * map)
{
  GError * error = NULL;
  GtkBuilder * builder = gtk_builder_new ();
  gtk_builder_add_from_file (builder, DATETIME_DIALOG_UI_FILE, &error);
  if (error != NULL) {
    /* We have to abort, we can't continue without the ui file */
    g_error ("Could not load ui file %s: %s", DATETIME_DIALOG_UI_FILE, error->message);
    g_error_free (error);
    return NULL;
  }

  gtk_builder_set_translation_domain (builder, GETTEXT_PACKAGE);

  GSettings * conf = g_settings_new (SETTINGS_INTERFACE);

#define WIG(name) GTK_WIDGET (gtk_builder_get_object (builder, name))

  GtkWidget * dlg = WIG ("locationsDialog");
  GtkWidget * tree = WIG ("locationsView");
  GObject * store = gtk_builder_get_object (builder, "locationsStore");

  /* Configure tree */
  TimezoneCompletion * completion = timezone_completion_new ();
  g_object_set_data (G_OBJECT (completion), "tzmap", map);
  g_object_set_data (G_OBJECT (completion), "store", store);
  g_signal_connect (completion, "match-selected", G_CALLBACK (timezone_selected), dlg);

  GtkCellRenderer * cell = gtk_cell_renderer_text_new ();
  g_object_set (cell, "editable", TRUE, NULL);
  g_signal_connect (cell, "editing-started", G_CALLBACK (handle_edit_started), completion);
  g_signal_connect (cell, "edited", G_CALLBACK (handle_edit), store);
  gtk_tree_view_insert_column_with_attributes (GTK_TREE_VIEW (tree), -1,
                                               _("Location"), cell,
                                               "text", COL_VISIBLE_NAME, NULL);
  GtkTreeViewColumn * loc_col = gtk_tree_view_get_column (GTK_TREE_VIEW (tree), 0);
  gtk_tree_view_column_set_expand (loc_col, TRUE);
  g_object_set_data (G_OBJECT (completion), "name-cell", cell);

  cell = gtk_cell_renderer_pixbuf_new ();
  gtk_tree_view_column_pack_start (loc_col, cell, FALSE);
  gtk_tree_view_column_add_attribute (loc_col, cell, "icon-name", COL_ICON);

  gtk_widget_set_has_tooltip (tree, TRUE);
  g_signal_connect (tree, "query-tooltip", G_CALLBACK (query_tooltip), cell);

  cell = gtk_cell_renderer_text_new ();
  gtk_tree_view_insert_column_with_attributes (GTK_TREE_VIEW (tree), -1,
                                               _("Time"), cell,
                                               "text", COL_TIME, NULL);

  GtkTreeSelection * selection = gtk_tree_view_get_selection (GTK_TREE_VIEW (tree));
  gtk_tree_selection_set_mode (selection, GTK_SELECTION_MULTIPLE);
  g_signal_connect (selection, "changed", G_CALLBACK (selection_changed), WIG ("removeButton"));
  selection_changed (selection, WIG ("removeButton"));

  g_signal_connect (WIG ("addButton"), "clicked", G_CALLBACK (handle_add), tree);
  g_signal_connect (WIG ("removeButton"), "clicked", G_CALLBACK (handle_remove), tree);

  fill_from_settings (store, conf);
  g_signal_connect_swapped (store, "row-deleted", G_CALLBACK (save_when_idle), dlg);
  g_signal_connect_swapped (store, "row-inserted", G_CALLBACK (save_when_idle), dlg);
  g_signal_connect_swapped (store, "row-changed", G_CALLBACK (save_when_idle), dlg);
  g_signal_connect_swapped (store, "rows-reordered", G_CALLBACK (save_when_idle), dlg);

  g_object_set_data_full (G_OBJECT (dlg), "conf", g_object_ref (conf), g_object_unref);
  g_object_set_data_full (G_OBJECT (dlg), "completion", completion, g_object_unref);
  g_signal_connect (dlg, "destroy", G_CALLBACK (dialog_closed), store);

  guint time_id = g_timeout_add_seconds (2, (GSourceFunc)update_times, dlg);
  g_object_set_data (G_OBJECT (dlg), "time-id", GINT_TO_POINTER(time_id));
  update_times (dlg);

#undef WIG

  g_object_unref (conf);
  g_object_unref (builder);

  return dlg;
}