/*
 * @file gtkscrollbook.c GTK+ Scrolling notebook widget
 * @ingroup pidgin
 */

/* pidgin
 *
 * Pidgin is the legal property of its developers, whose names are too numerous
 * to list here.  Please refer to the COPYRIGHT file distributed with this
 * source distribution.
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02111-1301  USA
 */

#include "gtkscrollbook.h"


static void pidgin_scroll_book_init (PidginScrollBook *scroll_book);
static void pidgin_scroll_book_class_init (PidginScrollBookClass *klass);
static void pidgin_scroll_book_forall (GtkContainer *c,
					 gboolean include_internals,
					 GtkCallback callback,
					 gpointer user_data);

GType
pidgin_scroll_book_get_type (void)
{
	static GType scroll_book_type = 0;

	if (!scroll_book_type)
	{
		static const GTypeInfo scroll_book_info =
		{
			sizeof (PidginScrollBookClass),
			NULL, /* base_init */
			NULL, /* base_finalize */
			(GClassInitFunc) pidgin_scroll_book_class_init,
			NULL, /* class_finalize */
			NULL, /* class_data */
			sizeof (PidginScrollBook),
			0,
			(GInstanceInitFunc) pidgin_scroll_book_init,
			NULL  /* value_table */
		};

		scroll_book_type = g_type_register_static(GTK_TYPE_VBOX,
							 "PidginScrollBook",
							 &scroll_book_info,
							 0);
	}

	return scroll_book_type;
}

static gboolean
scroll_left_cb(PidginScrollBook *scroll_book)
{
	int index;
	index = gtk_notebook_get_current_page(GTK_NOTEBOOK(scroll_book->notebook));

	if (index > 0)
		gtk_notebook_set_current_page(GTK_NOTEBOOK(scroll_book->notebook), index - 1);
	return TRUE;
}

static gboolean
scroll_right_cb(PidginScrollBook *scroll_book)
{
	int index, count;
	index = gtk_notebook_get_current_page(GTK_NOTEBOOK(scroll_book->notebook));
#if GTK_CHECK_VERSION(2,2,0)
	count = gtk_notebook_get_n_pages(GTK_NOTEBOOK(scroll_book->notebook));
#else
	count = g_list_length(GTK_NOTEBOOK(scroll_book->notebook)->children);
#endif

	if (index + 1 < count)
		gtk_notebook_set_current_page(GTK_NOTEBOOK(scroll_book->notebook), index + 1);
	return TRUE;
}

static void
refresh_scroll_box(PidginScrollBook *scroll_book, int index, int count)
{
	char *label;

	gtk_widget_show_all(GTK_WIDGET(scroll_book));
	if (count < 1)
		gtk_widget_hide_all(scroll_book->hbox);
	else {
		gtk_widget_show_all(scroll_book->hbox);
		if (count == 1) {
			gtk_widget_hide(scroll_book->label);
			gtk_widget_hide(scroll_book->left_arrow);
			gtk_widget_hide(scroll_book->right_arrow);
		}
	}

	label = g_strdup_printf("<span size='smaller' weight='bold'>(%d/%d)</span>", index+1, count);
	gtk_label_set_markup(GTK_LABEL(scroll_book->label), label);
	g_free(label);

	if (index == 0)
		gtk_widget_set_sensitive(scroll_book->left_arrow, FALSE);
	else
		gtk_widget_set_sensitive(scroll_book->left_arrow, TRUE);


	if (index + 1 == count)
		gtk_widget_set_sensitive(scroll_book->right_arrow, FALSE);
	else
		gtk_widget_set_sensitive(scroll_book->right_arrow, TRUE);
}


static void
page_count_change_cb(PidginScrollBook *scroll_book)
{
	int count;
	int index = gtk_notebook_get_current_page(GTK_NOTEBOOK(scroll_book->notebook));
#if GTK_CHECK_VERSION(2,2,0)
	count = gtk_notebook_get_n_pages(GTK_NOTEBOOK(scroll_book->notebook));
#else
	count = g_list_length(GTK_NOTEBOOK(scroll_book->notebook)->children);
#endif
	refresh_scroll_box(scroll_book, index, count);
}

static gboolean
scroll_close_cb(PidginScrollBook *scroll_book)
{
	gtk_widget_destroy(gtk_notebook_get_nth_page(GTK_NOTEBOOK(scroll_book->notebook), gtk_notebook_get_current_page(GTK_NOTEBOOK(scroll_book->notebook))));
	return FALSE;
}

static void
switch_page_cb(GtkNotebook *notebook, GtkNotebookPage *page, guint page_num, PidginScrollBook *scroll_book)
{
	int count;
#if GTK_CHECK_VERSION(2,2,0)
	count = gtk_notebook_get_n_pages(GTK_NOTEBOOK(scroll_book->notebook));
#else
	count = g_list_length(GTK_NOTEBOOK(scroll_book->notebook)->children);
#endif
	refresh_scroll_box(scroll_book, page_num, count);
}

static void
pidgin_scroll_book_add(GtkContainer *container, GtkWidget *widget)
{
	PidginScrollBook *scroll_book;

	g_return_if_fail(GTK_IS_WIDGET (widget));
	g_return_if_fail (widget->parent == NULL);

	scroll_book = PIDGIN_SCROLL_BOOK(container);
	scroll_book->children = g_list_append(scroll_book->children, widget);
	gtk_widget_show(widget);
	gtk_notebook_append_page(GTK_NOTEBOOK(scroll_book->notebook), widget, NULL);
	page_count_change_cb(PIDGIN_SCROLL_BOOK(container));
}

static void
pidgin_scroll_book_remove(GtkContainer *container, GtkWidget *widget)
{
	int page;
	PidginScrollBook *scroll_book;
	g_return_if_fail(GTK_IS_WIDGET(widget));

	scroll_book = PIDGIN_SCROLL_BOOK(container);
	scroll_book->children = g_list_remove(scroll_book->children, widget);
	/* gtk_widget_unparent(widget); */

	page = gtk_notebook_page_num(GTK_NOTEBOOK(PIDGIN_SCROLL_BOOK(container)->notebook), widget);
	if (page >= 0) {
		gtk_notebook_remove_page(GTK_NOTEBOOK(PIDGIN_SCROLL_BOOK(container)->notebook), page);
	}
}

static void
pidgin_scroll_book_forall(GtkContainer *container,
			   gboolean include_internals,
			   GtkCallback callback,
			   gpointer callback_data)
{
#if 0
	GList *children;
#endif
	PidginScrollBook *scroll_book;

	g_return_if_fail(GTK_IS_CONTAINER(container));

	scroll_book = PIDGIN_SCROLL_BOOK(container);

	if (include_internals) {
		(*callback)(scroll_book->hbox, callback_data);
		(*callback)(scroll_book->notebook, callback_data);
	}

#if 0
	children = scroll_book->children;

	while (children) {
		GtkWidget *child;
		child = children->data;
		children = children->next;
		(*callback)(child, callback_data);
	}
#endif
}

static void
pidgin_scroll_book_class_init (PidginScrollBookClass *klass)
{
	GtkContainerClass *container_class = (GtkContainerClass*)klass;

	container_class->add = pidgin_scroll_book_add;
	container_class->remove = pidgin_scroll_book_remove;
	container_class->forall = pidgin_scroll_book_forall;
}

static gboolean
close_button_left_cb(GtkWidget *widget, GdkEventCrossing *event, GtkLabel *label)
{
	static GdkCursor *ptr = NULL;
	if (ptr == NULL) {
		ptr = gdk_cursor_new(GDK_LEFT_PTR);
	}

	gtk_label_set_markup(label, "×");
	gdk_window_set_cursor(event->window, ptr);
	return FALSE;
}

static gboolean
close_button_entered_cb(GtkWidget *widget, GdkEventCrossing *event, GtkLabel *label)
{
	static GdkCursor *hand = NULL;
	if (hand == NULL) {
		hand = gdk_cursor_new(GDK_HAND2);
	}

	gtk_label_set_markup(label, "<u>×</u>");
	gdk_window_set_cursor(event->window, hand);
	return FALSE;
}

static void
pidgin_scroll_book_init (PidginScrollBook *scroll_book)
{
	GtkWidget *eb;
	GtkWidget *close_button;

	scroll_book->hbox = gtk_hbox_new(FALSE, 0);

	/* Close */
	eb = gtk_event_box_new();
	gtk_box_pack_end(GTK_BOX(scroll_book->hbox), eb, FALSE, FALSE, 0);
#if GTK_CHECK_VERSION(2,4,0)
	gtk_event_box_set_visible_window(GTK_EVENT_BOX(eb), FALSE);
#endif
	gtk_widget_set_events(eb, GDK_ENTER_NOTIFY_MASK | GDK_LEAVE_NOTIFY_MASK);
	close_button = gtk_label_new("×");
	g_signal_connect(G_OBJECT(eb), "enter-notify-event", G_CALLBACK(close_button_entered_cb), close_button);
	g_signal_connect(G_OBJECT(eb), "leave-notify-event", G_CALLBACK(close_button_left_cb), close_button);
	gtk_container_add(GTK_CONTAINER(eb), close_button);
	g_signal_connect_swapped(G_OBJECT(eb), "button-press-event", G_CALLBACK(scroll_close_cb), scroll_book);

	/* Right arrow */
	eb = gtk_event_box_new();
	gtk_box_pack_end(GTK_BOX(scroll_book->hbox), eb, FALSE, FALSE, 0);
	scroll_book->right_arrow = gtk_arrow_new(GTK_ARROW_RIGHT, GTK_SHADOW_NONE);
	gtk_container_add(GTK_CONTAINER(eb), scroll_book->right_arrow);
	g_signal_connect_swapped(G_OBJECT(eb), "button-press-event", G_CALLBACK(scroll_right_cb), scroll_book);

	/* Count */
	scroll_book->label = gtk_label_new(NULL);
	gtk_box_pack_end(GTK_BOX(scroll_book->hbox), scroll_book->label, FALSE, FALSE, 0);

	/* Left arrow */
	eb = gtk_event_box_new();
	gtk_box_pack_end(GTK_BOX(scroll_book->hbox), eb, FALSE, FALSE, 0);
	scroll_book->left_arrow = gtk_arrow_new(GTK_ARROW_LEFT, GTK_SHADOW_NONE);
	gtk_container_add(GTK_CONTAINER(eb), scroll_book->left_arrow);
	g_signal_connect_swapped(G_OBJECT(eb), "button-press-event", G_CALLBACK(scroll_left_cb), scroll_book);

	gtk_box_pack_start(GTK_BOX(scroll_book), scroll_book->hbox, FALSE, FALSE, 0);

	scroll_book->notebook = gtk_notebook_new();
	gtk_notebook_set_show_tabs(GTK_NOTEBOOK(scroll_book->notebook), FALSE);
	gtk_notebook_set_show_border(GTK_NOTEBOOK(scroll_book->notebook), FALSE);

	gtk_box_pack_start(GTK_BOX(scroll_book), scroll_book->notebook, TRUE, TRUE, 0);

	g_signal_connect_swapped(G_OBJECT(scroll_book->notebook), "remove", G_CALLBACK(page_count_change_cb), scroll_book);
	g_signal_connect(G_OBJECT(scroll_book->notebook), "switch-page", G_CALLBACK(switch_page_cb), scroll_book);
	gtk_widget_show_all(scroll_book->notebook);
}

GtkWidget *
pidgin_scroll_book_new()
{
	return g_object_new(PIDGIN_TYPE_SCROLL_BOOK, NULL);
}