#include <stdio.h>
#include "aspectbin.h"

static void aspect_bin_size_request(GtkWidget *, GtkRequisition *);
static void aspect_bin_size_allocate(GtkWidget *, GtkAllocation *);
static void aspect_bin_remove(GtkContainer *, GtkWidget *);
static void aspect_bin_forall(GtkContainer *, gboolean, GtkCallback, gpointer);

G_DEFINE_TYPE(AspectBin, aspect_bin, GTK_TYPE_BIN)

static void aspect_bin_init(AspectBin *ab)
{
	ab->child     = NULL;
	ab->ratio     = 1;
	ab->constrain = FALSE;
	ab->align     = 0;
}

static void aspect_bin_class_init(AspectBinClass *abc)
{
	GtkWidgetClass    *widget_class    = GTK_WIDGET_CLASS(abc);
	GtkContainerClass *container_class = GTK_CONTAINER_CLASS(abc);

	widget_class->size_request  = aspect_bin_size_request;
	widget_class->size_allocate = aspect_bin_size_allocate;

	container_class->remove = aspect_bin_remove;
	container_class->forall = aspect_bin_forall;
}

GtkWidget *aspect_bin_new(void)
{
	return GTK_WIDGET(g_object_new(ASPECT_BIN_TYPE, NULL));
}

static void aspect_bin_remove(GtkContainer *container, GtkWidget *child)
{
	AspectBin *abin = ASPECT_BIN(container);

	if (abin->child == child) {
		aspect_bin_set_body_widget(abin, NULL, 1);
	} else {
		GTK_CONTAINER_CLASS(aspect_bin_parent_class)->remove
			(container, child);
	}
}

static void aspect_bin_forall(GtkContainer *container,
                              gboolean      include_internals,
                              GtkCallback   callback,
                              gpointer      callback_data)
{
	AspectBin *abin = ASPECT_BIN(container);
	GtkBin     *bin = GTK_BIN(container);

	if (bin->child)
		callback(bin->child, callback_data);
	
	if (abin->child)
		callback(abin->child, callback_data);
}

static void
aspect_bin_size_request(GtkWidget *widget, GtkRequisition *requisition)
{
	AspectBin *abin = ASPECT_BIN(widget);
	GtkBin    *bin  = GTK_BIN(widget);
	GtkRequisition creq = {0}, areq = {0};

	if (bin->child && GTK_WIDGET_VISIBLE(bin->child)) {
		gtk_widget_size_request(bin->child, &creq);
	}

	if (abin->child && GTK_WIDGET_VISIBLE(abin->child)) {
		int wtmp, htmp;
		gtk_widget_size_request(abin->child, &areq);
		wtmp = areq.height * abin->ratio + 0.5;
		htmp = areq.width  / abin->ratio + 0.5;

		if (wtmp > areq.width) {
			areq.width  = wtmp;
		} else {
			areq.height = htmp;
		}
	}

	requisition->width  = areq.width + creq.width;
	requisition->height = MAX(areq.height, creq.height);
}

static void
aspect_bin_size_allocate(GtkWidget *widget, GtkAllocation *allocation)
{
	AspectBin *abin = ASPECT_BIN(widget);
	GtkBin    *bin  = GTK_BIN(widget);
	GtkRequisition creq = {0};
	GtkAllocation csize = {0}, asize = {0};
	
	/* First find the best fit for the constrained child. */
	if (abin->child && GTK_WIDGET_VISIBLE(abin->child)) {
		asize.height = allocation->height;
		asize.width  = asize.height * abin->ratio + 0.5;

		if (asize.width > allocation->width) {
			asize.width  = allocation->width;
			asize.height = asize.width / abin->ratio + 0.5;
		}
	}

	/* Now try to fit the other child. */
	if (bin->child && GTK_WIDGET_VISIBLE(bin->child)) {
		gtk_widget_get_child_requisition(bin->child, &creq);

		if (allocation->width - asize.width < creq.width) {
			/* It didn't fit, squish the constrained guy. */
			asize.width  = allocation->width - creq.width;
			asize.height = asize.width / abin->ratio + 0.5;
		}

		csize.width  = allocation->width - asize.width;
		csize.height = MIN(allocation->height, creq.height);
		if (abin->constrain) {
			csize.height = MAX(csize.height, asize.height);
		}
		csize.x = asize.width;
	}

	csize.y = (allocation->height - csize.height) * abin->align + 0.5;
	asize.y = (allocation->height - asize.height) * abin->align + 0.5;

	if (bin->child)
		gtk_widget_size_allocate(bin->child, &csize);
	if (abin->child)
		gtk_widget_size_allocate(abin->child, &asize);
}

void
aspect_bin_set_body_widget(AspectBin *ab, GtkWidget *widget, gfloat ratio)
{
	gboolean need_resize = FALSE;

	g_return_if_fail(IS_ASPECT_BIN(ab));
	g_return_if_fail(widget == NULL || GTK_IS_WIDGET(widget));
	g_return_if_fail(widget == NULL || widget->parent == NULL);

	if (ab->child == widget)
		return;
	
	if (ab->child) {
		need_resize |= GTK_WIDGET_VISIBLE(ab->child);
		gtk_widget_unparent(ab->child);
	}

	ab->child = widget;
	if (widget) {
		gtk_widget_set_parent(widget, GTK_WIDGET(ab));
		need_resize |= GTK_WIDGET_VISIBLE(widget);
	}

	if (GTK_WIDGET_VISIBLE(ab) && need_resize)
		gtk_widget_queue_resize(GTK_WIDGET(ab));
}