/*
 * Copyright (C) 2004 Red Hat, Inc.
 * Copyright (C) 2007 The Free Software Foundation
 * Copyright (C) 2008 Marco Barisione <marco@barisione.org>
 *
 * Based on evince code (shell/ev-sidebar.c) by: 
 * 	- Jonathan Blandford <jrb@alum.mit.edu>
 *
 * Base on eog code (src/eog-sidebar.c) by:
 *      - Lucas Rocha <lucasr@gnome.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

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

#include <string.h>
#include <gtk/gtk.h>
#include <gdk/gdkkeysyms.h>

#include "sidebar.h"

enum
{
    PROP_0,
    PROP_CURRENT_PAGE
};

enum
{
    PAGE_COLUMN_TITLE,
    PAGE_COLUMN_MENU_ITEM,
    PAGE_COLUMN_MAIN_WIDGET,
    PAGE_COLUMN_NOTEBOOK_INDEX,
    PAGE_COLUMN_NUM_COLS
};

enum
{
    SIGNAL_PAGE_ADDED,
    SIGNAL_PAGE_REMOVED,
    SIGNAL_LAST
};

static gint signals[SIGNAL_LAST];

struct _EmerillonSidebarPrivate
{
    GtkWidget *notebook;
    GtkWidget *select_button;
    GtkWidget *menu;
    GtkWidget *hbox;
    GtkWidget *label;

    GtkTreeModel *page_model;
};

G_DEFINE_TYPE (EmerillonSidebar, emerillon_sidebar, GTK_TYPE_BOX)

#define EMERILLON_SIDEBAR_GET_PRIVATE(object) \
    (G_TYPE_INSTANCE_GET_PRIVATE ((object), EMERILLON_TYPE_SIDEBAR, EmerillonSidebarPrivate))

static void
emerillon_sidebar_dispose (GObject *object)
{
  EmerillonSidebar *sidebar = EMERILLON_SIDEBAR (object);

  if (sidebar->priv->menu)
    {
      gtk_menu_detach (GTK_MENU (sidebar->priv->menu));
      sidebar->priv->menu = NULL;
    }

  if (sidebar->priv->page_model)
    {
      g_object_unref (sidebar->priv->page_model);
      sidebar->priv->page_model = NULL;
    }

  (* G_OBJECT_CLASS (emerillon_sidebar_parent_class)->dispose) (object);
}

static void
emerillon_sidebar_select_page (EmerillonSidebar *sidebar,
                                GtkTreeIter *iter)
{
  gchar *title;
  gint index;

  gtk_tree_model_get (sidebar->priv->page_model, iter,
      PAGE_COLUMN_TITLE, &title, 
      PAGE_COLUMN_NOTEBOOK_INDEX, &index,
      -1);

  gtk_notebook_set_current_page (GTK_NOTEBOOK (sidebar->priv->notebook), index);
  gtk_label_set_text (GTK_LABEL (sidebar->priv->label), title);

  g_free (title);
}

void
emerillon_sidebar_set_page (EmerillonSidebar *sidebar,
                             GtkWidget *main_widget)
{
  GtkTreeIter iter;
  gboolean valid;

  valid = gtk_tree_model_get_iter_first (sidebar->priv->page_model, &iter);

  while (valid)
    {
      GtkWidget *widget;

      gtk_tree_model_get (sidebar->priv->page_model, &iter,
          PAGE_COLUMN_MAIN_WIDGET, &widget,
          -1);

      if (widget == main_widget)
        {
          emerillon_sidebar_select_page (sidebar, &iter);
          valid = FALSE;
        }
      else
        {
          valid = gtk_tree_model_iter_next (sidebar->priv->page_model, &iter);
        }

      g_object_unref (widget);
  }

  g_object_notify (G_OBJECT (sidebar), "current-page");
}

static GtkWidget *
emerillon_sidebar_get_current_page (EmerillonSidebar *sidebar)
{
  GtkNotebook *notebook = GTK_NOTEBOOK (sidebar->priv->notebook);

  return gtk_notebook_get_nth_page (
    notebook, gtk_notebook_get_current_page (notebook));
}

static void
emerillon_sidebar_set_property (GObject *object,
                                 guint prop_id,
                                 const GValue *value,
                                 GParamSpec *pspec)
{
  EmerillonSidebar *sidebar = EMERILLON_SIDEBAR (object);

  switch (prop_id)
    {
      case PROP_CURRENT_PAGE:
        emerillon_sidebar_set_page (sidebar, g_value_get_object (value));	
        break;
      default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
    }
}

static void
emerillon_sidebar_get_property (GObject *object,
                                 guint prop_id,
                                 GValue *value,
                                 GParamSpec *pspec)
{
  EmerillonSidebar *sidebar = EMERILLON_SIDEBAR (object);

  switch (prop_id)
    {
      case PROP_CURRENT_PAGE:
        g_value_set_object (value,
            emerillon_sidebar_get_current_page (sidebar));
        break;
      default:
        G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
    }
}

static void
emerillon_sidebar_class_init (EmerillonSidebarClass *emerillon_sidebar_class)
{
  GObjectClass *g_object_class;

  g_object_class = G_OBJECT_CLASS (emerillon_sidebar_class);

  g_type_class_add_private (g_object_class, sizeof (EmerillonSidebarPrivate));

  g_object_class->dispose = emerillon_sidebar_dispose;
  g_object_class->get_property = emerillon_sidebar_get_property;
  g_object_class->set_property = emerillon_sidebar_set_property;

  g_object_class_install_property (g_object_class,
      PROP_CURRENT_PAGE,
      g_param_spec_object ("current-page",
          "Current page",
          "The currently visible page",
          GTK_TYPE_WIDGET,
          G_PARAM_READWRITE));

  signals[SIGNAL_PAGE_ADDED] = g_signal_new ("page-added",
      EMERILLON_TYPE_SIDEBAR, G_SIGNAL_RUN_FIRST,
      G_STRUCT_OFFSET (EmerillonSidebarClass, page_added),
      NULL, NULL, g_cclosure_marshal_VOID__OBJECT,
      G_TYPE_NONE, 1, GTK_TYPE_WIDGET);

  signals[SIGNAL_PAGE_REMOVED] = g_signal_new ("page-removed",
      EMERILLON_TYPE_SIDEBAR, G_SIGNAL_RUN_FIRST,
      G_STRUCT_OFFSET (EmerillonSidebarClass, page_removed),
      NULL, NULL, g_cclosure_marshal_VOID__OBJECT,
      G_TYPE_NONE, 1, GTK_TYPE_WIDGET);
}

static void
emerillon_sidebar_menu_position_under (GtkMenu *menu,
                                         gint *x,
                                         gint *y,
                                         gboolean *push_in,
                                         gpointer user_data)
{
  GtkWidget *widget;

  g_return_if_fail (GTK_IS_BUTTON (user_data));
  g_return_if_fail (!gtk_widget_get_has_window (GTK_WIDGET (user_data)));
  
  widget = GTK_WIDGET (user_data);

  gdk_window_get_origin (gtk_widget_get_window (widget), x, y);

  GtkAllocation allocation;
  gtk_widget_get_allocation (widget, &allocation);
  *x += allocation.x;
  *y += allocation.y + allocation.height;

  *push_in = FALSE;
}

static gboolean
emerillon_sidebar_select_button_press_cb (GtkWidget *widget,
                                           GdkEventButton *event,
                                           gpointer user_data)
{
  EmerillonSidebar *sidebar = EMERILLON_SIDEBAR (user_data);

  if (event->button == 1)
    {
      gint preferred_width;
      gint width;

      GtkAllocation allocation;
      gtk_widget_get_allocation (widget, &allocation);
      width = allocation.width;

      gtk_widget_set_size_request (sidebar->priv->menu, -1, -1);
      gtk_widget_get_preferred_width(sidebar->priv->menu, NULL, 
          &preferred_width);
      gtk_widget_set_size_request (sidebar->priv->menu,
          MAX (width, preferred_width), -1);

      gtk_widget_grab_focus (widget);

      gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (widget), TRUE);

      gtk_menu_popup (GTK_MENU (sidebar->priv->menu),
          NULL, NULL, emerillon_sidebar_menu_position_under, widget,
          event->button, event->time);

      return TRUE;
    }

  return FALSE;
}

static gboolean
emerillon_sidebar_select_button_key_press_cb (GtkWidget *widget,
                                               GdkEventKey *event,
                                               gpointer user_data)
{
  EmerillonSidebar *sidebar = EMERILLON_SIDEBAR (user_data);

  if (event->keyval == GDK_KEY_space ||
      event->keyval == GDK_KEY_KP_Space ||
      event->keyval == GDK_KEY_Return ||
      event->keyval == GDK_KEY_KP_Enter)
    {
      gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (widget), TRUE);

      gtk_menu_popup (GTK_MENU (sidebar->priv->menu),
          NULL, NULL, emerillon_sidebar_menu_position_under, widget,
          1, event->time);

      return TRUE;
    }

  return FALSE;
}

static void
emerillon_sidebar_close_clicked_cb (GtkWidget *widget,
                                     gpointer user_data)
{
  EmerillonSidebar *sidebar = EMERILLON_SIDEBAR (user_data);

  gtk_widget_hide (GTK_WIDGET (sidebar));
}

static void
emerillon_sidebar_menu_deactivate_cb (GtkWidget *widget,
                                       gpointer user_data)
{
  GtkWidget *menu_button;

  menu_button = GTK_WIDGET (user_data);

  gtk_toggle_button_set_active (GTK_TOGGLE_BUTTON (menu_button), FALSE);
}

static void
emerillon_sidebar_menu_detach_cb (GtkWidget *widget,
                                   GtkMenu *menu)
{
  EmerillonSidebar *sidebar = EMERILLON_SIDEBAR (widget);

  sidebar->priv->menu = NULL;
}

static void
emerillon_sidebar_menu_item_activate_cb (GtkWidget *widget,
                                          gpointer user_data)
{
  EmerillonSidebar *sidebar = EMERILLON_SIDEBAR (user_data);
  GtkTreeIter iter;
  GtkWidget *menu_item, *item;
  gboolean valid;

  menu_item = gtk_menu_get_active (GTK_MENU (sidebar->priv->menu));
  valid = gtk_tree_model_get_iter_first (sidebar->priv->page_model, &iter);

  while (valid)
    {
      gtk_tree_model_get (sidebar->priv->page_model, &iter,
          PAGE_COLUMN_MENU_ITEM, &item,
          -1);

      if (item == menu_item)
        {
          emerillon_sidebar_select_page (sidebar, &iter);
          valid = FALSE;
        }
      else
        {
          valid = gtk_tree_model_iter_next (sidebar->priv->page_model, &iter);
        }

      g_object_unref (item);
    }

  g_object_notify (G_OBJECT (sidebar), "current-page");
}

static void
emerillon_sidebar_init (EmerillonSidebar *sidebar)
{
  GtkWidget *hbox;
  GtkWidget *close_button;
  GtkWidget *select_hbox;
  GtkWidget *arrow;
  GtkWidget *image;

  sidebar->priv = EMERILLON_SIDEBAR_GET_PRIVATE (sidebar);

  gtk_orientable_set_orientation (GTK_ORIENTABLE (sidebar),
      GTK_ORIENTATION_VERTICAL);

  /* data model */
  sidebar->priv->page_model = (GtkTreeModel *) gtk_list_store_new (
      PAGE_COLUMN_NUM_COLS,
      G_TYPE_STRING,
      GTK_TYPE_WIDGET,
      GTK_TYPE_WIDGET,
      G_TYPE_INT);

  /* top option menu */
  hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0);
  sidebar->priv->hbox = hbox;
  gtk_box_pack_start (GTK_BOX (sidebar), hbox, FALSE, FALSE, 0);
  gtk_widget_show (hbox);

  sidebar->priv->select_button = gtk_toggle_button_new ();
  gtk_button_set_relief (GTK_BUTTON (sidebar->priv->select_button), 
      GTK_RELIEF_NONE);
  gtk_widget_set_sensitive (sidebar->priv->select_button, FALSE);

  g_signal_connect (sidebar->priv->select_button, "button_press_event",
      G_CALLBACK (emerillon_sidebar_select_button_press_cb),
      sidebar);

  g_signal_connect (sidebar->priv->select_button, "key_press_event",
      G_CALLBACK (emerillon_sidebar_select_button_key_press_cb),
      sidebar);

  select_hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0);

  sidebar->priv->label = gtk_label_new ("");
  gtk_label_set_ellipsize (GTK_LABEL (sidebar->priv->label),
                           PANGO_ELLIPSIZE_END);
  gtk_misc_set_alignment (GTK_MISC (sidebar->priv->label),
                          0, 0.5);

  gtk_box_pack_start (GTK_BOX (select_hbox),
      sidebar->priv->label,
      TRUE, TRUE, 0);

  gtk_widget_show (sidebar->priv->label);

  arrow = gtk_arrow_new (GTK_ARROW_DOWN, GTK_SHADOW_NONE);
  gtk_box_pack_end (GTK_BOX (select_hbox), arrow, FALSE, FALSE, 0);
  gtk_widget_show (arrow);

  gtk_container_add (GTK_CONTAINER (sidebar->priv->select_button), select_hbox);
  gtk_widget_show (select_hbox);

  gtk_box_pack_start (GTK_BOX (hbox), sidebar->priv->select_button, TRUE, TRUE, 0);
  gtk_widget_show (sidebar->priv->select_button);

  close_button = gtk_button_new ();

  gtk_button_set_relief (GTK_BUTTON (close_button), GTK_RELIEF_NONE);

  g_signal_connect (close_button, "clicked",
      G_CALLBACK (emerillon_sidebar_close_clicked_cb),
      sidebar);

  image = gtk_image_new_from_stock (GTK_STOCK_CLOSE,
      GTK_ICON_SIZE_MENU);
  gtk_container_add (GTK_CONTAINER (close_button), image);
  gtk_widget_show (image);

  gtk_box_pack_end (GTK_BOX (hbox), close_button, FALSE, FALSE, 0);
  gtk_widget_show (close_button);

  sidebar->priv->menu = gtk_menu_new ();

  g_signal_connect (sidebar->priv->menu, "deactivate",
      G_CALLBACK (emerillon_sidebar_menu_deactivate_cb),
      sidebar->priv->select_button);

  gtk_menu_attach_to_widget (GTK_MENU (sidebar->priv->menu),
      GTK_WIDGET (sidebar),
      emerillon_sidebar_menu_detach_cb);

  gtk_widget_show (sidebar->priv->menu);

  sidebar->priv->notebook = gtk_notebook_new ();

  gtk_notebook_set_show_border (GTK_NOTEBOOK (sidebar->priv->notebook), FALSE);
  gtk_notebook_set_show_tabs (GTK_NOTEBOOK (sidebar->priv->notebook), FALSE);

  gtk_box_pack_start (GTK_BOX (sidebar), sidebar->priv->notebook,
      TRUE, TRUE, 0);

  gtk_widget_show (sidebar->priv->notebook);
}

GtkWidget *
emerillon_sidebar_new (void)
{
  GtkWidget *sidebar;

  sidebar = g_object_new (EMERILLON_TYPE_SIDEBAR, NULL);

  return sidebar;
}

/**
 * emerillon_sidebar_add_page:
 * @sidebar: (in): An #EmerillonSidebar instance
 * @title: (in): Sidebar title
 * @main_widget: (in): A #GtkWidget which should be embedded in the sidebar
 *
 * Adds a new page to the sidebar
 *
 * See: emerillon_window_get_sidebar()
 */
void
emerillon_sidebar_add_page (EmerillonSidebar *sidebar,
                             const gchar *title,
                             GtkWidget *main_widget)
{
  GtkTreeIter iter;
  GtkWidget *menu_item;
  gchar *label_title;
  gint index;

  g_return_if_fail (EMERILLON_IS_SIDEBAR (sidebar));
  g_return_if_fail (GTK_IS_WIDGET (main_widget));

  index = gtk_notebook_append_page (GTK_NOTEBOOK (sidebar->priv->notebook),
      main_widget, NULL);

  menu_item = gtk_image_menu_item_new_with_label (title);

  g_signal_connect (menu_item, "activate",
      G_CALLBACK (emerillon_sidebar_menu_item_activate_cb),
      sidebar);

  gtk_widget_show (menu_item);

  gtk_menu_shell_append (GTK_MENU_SHELL (sidebar->priv->menu),
      menu_item);

  /* Insert and move to end */
  gtk_list_store_insert_with_values (GTK_LIST_STORE (sidebar->priv->page_model),
      &iter, 0,
      PAGE_COLUMN_TITLE, title,
      PAGE_COLUMN_MENU_ITEM, menu_item,
      PAGE_COLUMN_MAIN_WIDGET, main_widget,
      PAGE_COLUMN_NOTEBOOK_INDEX, index,
      -1);

  gtk_list_store_move_before (GTK_LIST_STORE(sidebar->priv->page_model),
      &iter, 
      NULL);

  /* Set the first item added as active */
  gtk_tree_model_get_iter_first (sidebar->priv->page_model, &iter);
  gtk_tree_model_get (sidebar->priv->page_model,
      &iter,
      PAGE_COLUMN_TITLE, &label_title,
      PAGE_COLUMN_NOTEBOOK_INDEX, &index,
      -1);

  gtk_menu_set_active (GTK_MENU (sidebar->priv->menu), index);

  gtk_label_set_text (GTK_LABEL (sidebar->priv->label), label_title);

  gtk_notebook_set_current_page (GTK_NOTEBOOK (sidebar->priv->notebook),
      index);

  g_free (label_title);

  if (gtk_notebook_get_n_pages (GTK_NOTEBOOK (sidebar->priv->notebook)) > 1)
    gtk_widget_set_sensitive (sidebar->priv->select_button, TRUE);

  g_signal_emit (G_OBJECT (sidebar), signals[SIGNAL_PAGE_ADDED],
      0, main_widget);
}

void
emerillon_sidebar_remove_page (EmerillonSidebar *sidebar,
                                GtkWidget *main_widget)
{
  GtkTreeIter iter;
  GtkWidget *widget, *menu_item;
  gboolean valid;
  gboolean visible;
  gint index;

  g_return_if_fail (EMERILLON_IS_SIDEBAR (sidebar));
  g_return_if_fail (GTK_IS_WIDGET (main_widget));

  valid = gtk_tree_model_get_iter_first (sidebar->priv->page_model, &iter);

  while (valid)
    {
      gtk_tree_model_get (sidebar->priv->page_model, &iter,
          PAGE_COLUMN_NOTEBOOK_INDEX, &index,
          PAGE_COLUMN_MENU_ITEM, &menu_item,
          PAGE_COLUMN_MAIN_WIDGET, &widget,
          -1);

      if (widget == main_widget)
          break;
      else
          valid = gtk_tree_model_iter_next (sidebar->priv->page_model, &iter);

      g_object_unref (menu_item);
      g_object_unref (widget);
    }

  if (valid)
    {
      visible = (index == gtk_notebook_get_current_page (
          GTK_NOTEBOOK (sidebar->priv->notebook)));

      gtk_notebook_remove_page (GTK_NOTEBOOK (sidebar->priv->notebook), 
          index);

      gtk_container_remove (GTK_CONTAINER (sidebar->priv->menu), menu_item);

      gtk_list_store_remove (GTK_LIST_STORE (sidebar->priv->page_model), 
          &iter);

      /* If we removed the visible tab, we select the first page or remove
       * the text in the dropdown menu if no page is left */
      if (visible)
        {
          if (!emerillon_sidebar_is_empty(sidebar))
            {
              valid = gtk_tree_model_get_iter_first (sidebar->priv->page_model, &iter);
              emerillon_sidebar_select_page (sidebar, &iter);
            }
          else
            gtk_label_set_text (GTK_LABEL (sidebar->priv->label), "");
        }

      if (gtk_notebook_get_n_pages (GTK_NOTEBOOK (sidebar->priv->notebook)) <= 1)
        gtk_widget_set_sensitive (sidebar->priv->select_button, FALSE);

      g_signal_emit (G_OBJECT (sidebar),
          signals[SIGNAL_PAGE_REMOVED], 0, main_widget);
    }
}

/**
 * emerillon_sidebar_get_n_pages:
 * @sidebar: (in): An #EmerillonSidebar instance
 *
 * Returns the number of pages @sidebar has.
 *
 * Return value: The number of pages @sidebar has. If @sidebar isn't
 * an #EmerillonSidebar instance this function returns #TRUE.
 */
gint
emerillon_sidebar_get_n_pages (EmerillonSidebar *sidebar)
{
  g_return_val_if_fail (EMERILLON_IS_SIDEBAR (sidebar), TRUE);

  return gtk_tree_model_iter_n_children (
      GTK_TREE_MODEL (sidebar->priv->page_model), NULL);
}

/**
 * emerillon_sidebar_is_empty:
 * @sidebar: (in): An #EmerillonSidebar instance
 *
 * Checks if the @sidebar is empty
 *
 * Return value: #TRUE if @sidebar has no pages or isn't
 * an #EmerillonSidebar instance
 */
gboolean
emerillon_sidebar_is_empty (EmerillonSidebar *sidebar)
{
  g_return_val_if_fail (EMERILLON_IS_SIDEBAR (sidebar), TRUE);

  return gtk_tree_model_iter_n_children (
      GTK_TREE_MODEL (sidebar->priv->page_model), NULL) == 0;
}
