/* draftpaper.c    draft paper
 * Copyright (c) 2004 by SmartLu <smartlu@eyou.com> All Rights Reserved
 * Distributed under the terms of the GNU General Public License (GPL)
 * See the GNU Library General Public License for more details.
 */

#include "srecite.h"

static GtkWidget *draft_win;
static GtkWidget *drawing_area;

static GtkWidget *quit_button,*reset_button;

/* 绘制区的后端位图 */
static GdkPixmap *pixmap = NULL;

/* 创建一个适当大小的后端位图 */
static gint configure_event( GtkWidget         *widget,
                             GdkEventConfigure *event )
{
	if (pixmap)
		g_object_unref (pixmap);

	pixmap = gdk_pixmap_new (widget->window,
			widget->allocation.width,
			widget->allocation.height,
			-1);
	
	gdk_draw_rectangle (pixmap,
			widget->style->white_gc,
			TRUE,
			0, 0,
			widget->allocation.width,
			widget->allocation.height);

	return TRUE;
}

/*  从后端位图重新绘制屏幕 */
static gint expose_event( GtkWidget      *widget,
                          GdkEventExpose *event )
{
	gdk_draw_drawable (widget->window,
			widget->style->fg_gc[GTK_WIDGET_STATE (widget)],
			pixmap,
			event->area.x, event->area.y,
			event->area.x, event->area.y,
			event->area.width, event->area.height);

	return FALSE;
}

/* 在屏幕上绘制一个矩形 */
static void draw_brush( GtkWidget *widget,
                        gdouble    x,
                        gdouble    y)
{
	GdkRectangle update_rect;

	update_rect.x = x - 3;
	update_rect.y = y - 3;
	update_rect.width = 6;
	update_rect.height = 6;
	
	gdk_draw_rectangle (pixmap,
			widget->style->black_gc,
			TRUE,
			update_rect.x, update_rect.y,
			update_rect.width, update_rect.height);

	gtk_widget_queue_draw_area (widget,
			update_rect.x, update_rect.y,
			update_rect.width, update_rect.height);
}

/* erase big rectangle */
static void erase_brush( GtkWidget *widget,
                        gdouble    x,
                        gdouble    y)
{
	GdkRectangle update_rect;

	update_rect.x = x - 10;
	update_rect.y = y - 10;
	update_rect.width = 20;
	update_rect.height = 20;
	
	gdk_draw_rectangle (pixmap,
			widget->style->white_gc,
			TRUE,
			update_rect.x, update_rect.y,
			update_rect.width, update_rect.height);

	gtk_widget_queue_draw_area (widget,
			update_rect.x, update_rect.y,
			update_rect.width, update_rect.height);
}

static gint button_press_event( GtkWidget      *widget,
                                GdkEventButton *event )
{
	if (event->button == 1 && pixmap != NULL)
		draw_brush (widget, event->x, event->y);
	//erase
	if (event->button == 3 && pixmap != NULL)
		erase_brush (widget, event->x, event->y);

	return TRUE;
}

static gint motion_notify_event( GtkWidget *widget,
                                 GdkEventMotion *event )
{
	int x, y;
	GdkModifierType state;

	if (event->is_hint)
		gdk_window_get_pointer (event->window, &x, &y, &state);
	else
	{
		x = event->x;
		y = event->y;
		state = event->state;
	}

	if (state & GDK_BUTTON1_MASK && pixmap != NULL)
		draw_brush (widget, x, y);
	//erase
	if (state & GDK_BUTTON3_MASK && pixmap != NULL)
		erase_brush (widget, x, y);

	return TRUE;
}

void draft_quit()
{
	gtk_grab_remove(draft_win);
	gtk_widget_destroy(draft_win);
}

void draft_reset()
{

	gtk_widget_set_size_request (GTK_WIDGET(drawing_area), 500, 400);
}
/* window of draftpaer */
void draftpaper_window()
{
	GtkWidget *vbox,*hbox,*h_line;

	draft_win = gtk_window_new (GTK_WINDOW_TOPLEVEL);
	gtk_widget_set_name (draft_win, "Draft Paper");
	gtk_window_set_title(GTK_WINDOW(draft_win),
			"Draft Paper - left draw,right erase");
	
	vbox = gtk_vbox_new (FALSE, 0);
	gtk_container_add (GTK_CONTAINER (draft_win), vbox);
	gtk_widget_show (vbox);

	g_signal_connect (G_OBJECT (draft_win), "destroy",
			G_CALLBACK (draft_quit), NULL);

/* 创建绘图区 */
	drawing_area = gtk_drawing_area_new ();
	gtk_widget_set_size_request (GTK_WIDGET(drawing_area), 500, 400);
	gtk_box_pack_start (GTK_BOX (vbox), drawing_area, TRUE, TRUE, 0);

	gtk_widget_show (drawing_area);

/* 用于处理后端位图的信号 */
	g_signal_connect (G_OBJECT (drawing_area), "expose_event",
			G_CALLBACK (expose_event), NULL);
	g_signal_connect (G_OBJECT (drawing_area),"configure_event",
			G_CALLBACK (configure_event), NULL);

/* 事件信号 */
	g_signal_connect (G_OBJECT (drawing_area), "motion_notify_event",
			G_CALLBACK (motion_notify_event), NULL);
	g_signal_connect (G_OBJECT (drawing_area), "button_press_event",
			G_CALLBACK (button_press_event), NULL);

	gtk_widget_set_events (drawing_area, GDK_EXPOSURE_MASK
			| GDK_LEAVE_NOTIFY_MASK
			| GDK_BUTTON_PRESS_MASK
			| GDK_POINTER_MOTION_MASK
			| GDK_POINTER_MOTION_HINT_MASK);

/* h_line */
	h_line = gtk_hseparator_new();
	gtk_box_pack_start(GTK_BOX(vbox),h_line,FALSE,FALSE,0);
	gtk_widget_show(h_line);

/* 退出按钮 */
/* hbox */
	hbox = gtk_hbox_new(TRUE,0);
	gtk_box_pack_start(GTK_BOX(vbox),hbox,FALSE,FALSE,0);
	gtk_widget_show(hbox);
	
	//reset button
	reset_button = create_img_button(PRE_DIR"icon/reset.png","Reset","Reset",
				draft_reset,
				reset_button);
	gtk_box_pack_start (GTK_BOX (hbox), reset_button, FALSE, FALSE, 0);
	gtk_widget_show (reset_button);

	//quit button
	quit_button = create_img_button(PRE_DIR"icon/exit.png","Quit","Quit",
				draft_quit,
				quit_button);
	gtk_box_pack_start (GTK_BOX (hbox), quit_button, FALSE, FALSE, 0);
	gtk_widget_show (quit_button);

	gtk_widget_show (draft_win);

}