/*
 * GdiffOverview widget module
 *
 * Copyright INOUE Seiichiro <inoue@ainet.or.jp>, licensed under the GPL.
 */
#include <gtk/gtksignal.h>
#include "gdiffoverview.h"
#include "style.h"


/* Keys for gtk_object_[get|set]_data() for drawing area */
#define OV_DAREA_KEY		"n"

/* Private function declarations */
static void gdiff_overview_class_init(GdiffOverviewClass *klass);
static void gdiff_overview_init(GdiffOverview *overview);

static void gdiff_overview_draw_lines(GtkWidget *darea, GdkEventExpose *event, gpointer data);


static GtkHBoxClass *parent_class = NULL;

GtkType
gdiff_overview_get_type(void)
{
  static GtkType overview_type = 0;

  if (!overview_type) {
      static const GtkTypeInfo overview_info = {
		  "GdiffOverview",
		  sizeof(GdiffOverview),
		  sizeof(GdiffOverviewClass),
		  (GtkClassInitFunc)gdiff_overview_class_init,
		  (GtkObjectInitFunc)gdiff_overview_init,
		  /* reserved_1 */ NULL,
		  /* reserved_2 */ NULL,
		  (GtkClassInitFunc)NULL,
      };
      overview_type = gtk_type_unique(GTK_TYPE_HBOX, &overview_info);
  }
  
  return overview_type;
}

static void
gdiff_overview_class_init(GdiffOverviewClass *klass)
{
	parent_class = gtk_type_class(GTK_TYPE_HBOX);
}

static void
gdiff_overview_init(GdiffOverview *overview)
{
	overview->num_ranges = 0;
	overview->ranges = NULL;
	overview->dareas = NULL;
}

GtkWidget*
gdiff_overview_new(int num_ranges, GtkAdjustment **adj_array)
{
	GdiffOverview *overview;
	GtkHBox *hbox;
	GtkWidget *range;
	GtkWidget *darea;
	int n;

	overview = gtk_type_new(GDIFF_TYPE_OVERVIEW);

	overview->num_ranges = num_ranges;
	overview->ranges = g_new(GdiffRange*, num_ranges);
	overview->dareas = g_new(GtkDrawingArea*, num_ranges-1);

	hbox = GTK_HBOX(overview);

	for (n = 0; n < overview->num_ranges; n++) {
		char *style_name;
		
		range = gdiff_range_new(NULL);
		overview->ranges[n] = GDIFF_RANGE(range);

		style_name = g_strdup_printf("file%d overview", n+1);
		gtk_widget_set_name(range, style_name);
		g_free(style_name);

		style_set_gdiff_range(range, n);

		gdiff_range_size(GDIFF_RANGE(range), WIDTH_OVERVIEW, 0);
		gtk_box_pack_start(GTK_BOX(hbox), range, FALSE, FALSE, 0);
		gtk_widget_show(range);

		if (n != overview->num_ranges-1) {
			darea = gtk_drawing_area_new();
			overview->dareas[n] = GTK_DRAWING_AREA(darea);
			gtk_widget_set_name(darea, "drawing overview");

			style_set_drawingarea(darea);
			gtk_drawing_area_size(GTK_DRAWING_AREA(darea), WIDTH_OVERVIEW, 0);
			gtk_object_set_data(GTK_OBJECT(darea),
								OV_DAREA_KEY, GINT_TO_POINTER(n));
			gtk_signal_connect(GTK_OBJECT(darea), "expose_event",
							   GTK_SIGNAL_FUNC(gdiff_overview_draw_lines), overview);
			gtk_box_pack_start(GTK_BOX(hbox), darea, FALSE, FALSE, 0);
			gtk_widget_show(darea);
		}
	}
	
	gdiff_overview_set_adjustment(overview, adj_array);
	
	return GTK_WIDGET(overview);
}


/** Interfaces **/
void
gdiff_overview_set_adjustment(GdiffOverview *overview, GtkAdjustment **adj_array)
{
	int n;
	
	g_return_if_fail(overview != NULL);
	g_return_if_fail(GDIFF_IS_OVERVIEW(overview));

	for (n = 0; n < overview->num_ranges; n++) {
		gdiff_range_set_adjustment(overview->ranges[n], adj_array[n]);
	}
}

/**
 * gdiff_overview_insert_paintrange:
 * Internally, set it for GdiffRange widgets.
 **/
void
gdiff_overview_insert_paintrange(GdiffOverview *overview, const gdouble *begin_array, const gdouble *end_array)
{
	int n;
	
	g_return_if_fail(overview != NULL);
	g_return_if_fail(GDIFF_IS_OVERVIEW(overview));

	for (n = 0; n < overview->num_ranges; n++) {
		gdiff_range_insert_paintrange(overview->ranges[n],
									  begin_array[n], end_array[n]);
	}
}

/**
 * gdiff_overview_set_color:
 **/
void
gdiff_overview_set_color(GdiffOverview *overview, GdkColor **fg_array, GdkColor **bg_array)
{
	int n;
	
	g_return_if_fail(overview != NULL);
	g_return_if_fail(GDIFF_IS_OVERVIEW(overview));

	for (n = 0; n < overview->num_ranges; n++) {
		if (fg_array[n])
			gdiff_range_set_foreground(overview->ranges[n], fg_array[n]);
		if (bg_array[n])
			gdiff_range_set_background(overview->ranges[n], bg_array[n]);
	}
}


/** Internal functions **/
#define lines_intersect(y1, y2, top, bottom) \
	((y1 >= top && y1 <= bottom) || (y2 >= top && y2 <= bottom))

/**
 * gdiff_overview_draw_lines:
 * Using range values, which are kept in GdiffRange widgets,
 * draw lines on drawingarea widget.
 **/
static void
gdiff_overview_draw_lines(GtkWidget *darea, GdkEventExpose *event, gpointer data)
{
	GdiffOverview *overview = data;
	int num = GPOINTER_TO_INT(gtk_object_get_data(GTK_OBJECT(darea), OV_DAREA_KEY));
	GdkWindow *w = darea->window;
	GdkGC *gc = darea->style->fg_gc[GTK_STATE_NORMAL];
	int darea_width;
	int darea_height;
	const GSList *list1 = overview->ranges[num]->range_list;/* left GdiffRange */
	const GSList *list2 = overview->ranges[num+1]->range_list;/* right GdiffRange */
	
	gdk_window_get_size(w, &darea_width, &darea_height);
	
	while (list1 && list2) {
		const PaintRange *pr1 = list1->data;
		const PaintRange *pr2 = list2->data;
		int y1, y2;
		
		y1 = darea_height * (pr1->begin + pr1->end) / 2;
		y2 = darea_height * (pr2->begin + pr2->end) / 2.0;
		
		if (lines_intersect(y1, y2,
							event->area.y, event->area.y+event->area.height)) {
			gdk_draw_line(w, gc, 0, y1, darea_width, y2);
		}
		list1 = g_slist_next(list1);
		list2 = g_slist_next(list2);
	}
}