#include <string.h>
#include <stdio.h>

#include "wayland.h"
#include "drw.h"
#include "xdg-shell-client-protocol.h"

/* macro definitions */
#define match_then_bind(obj, inter, ver) \
	if (strcmp(interface, inter.name) == 0) { \
		obj = wl_registry_bind(registry, name, &inter, ver);

#define end_match }
#define or_match } else

/* struct definitions */
typedef struct {
	unsigned width;
	unsigned height;
	struct {
		struct wl_surface *wl;
		struct xdg_surface *xdg;
		struct xdg_toplevel *toplevel;
	} surface;
	Canvas *canvas;
	Font *font;
} Window;


static void buffer_release(void *data, struct wl_buffer *buffer);
static void draw_frame();
static void surface_configure(void *data, struct xdg_surface *surface, uint32_t serial);
static void toplevel_configure(void *data, struct xdg_toplevel *toplevel, int32_t width, int32_t height, struct wl_array *states);
static void toplevel_close(void *data, struct xdg_toplevel *toplevel);
static void wm_base_ping(void *data, struct xdg_wm_base *wm_base, uint32_t serial);
static void registry_global(void *data, struct wl_registry *registry, uint32_t name, const char *interface, uint32_t version);
static void registry_global_remove(void *data, struct wl_registry *registry, uint32_t name);


/* global variables */
static const struct wl_registry_listener registry_listener = {
	.global = registry_global,
	.global_remove = registry_global_remove
};

static const struct wl_buffer_listener buffer_listener = {
	.release = buffer_release
};

static const struct xdg_surface_listener surface_listener = {
	.configure = surface_configure,
};

static const struct xdg_toplevel_listener toplevel_listener = {
	.configure = toplevel_configure,
	.close = toplevel_close
};

static const struct xdg_wm_base_listener wm_base_listener = {
	.ping = wm_base_ping
};

struct client_state state = { 0 };
Window win = { 0 };
int running = 1;

#include "config.h"

/* function implementation */
void
buffer_release(void *data, struct wl_buffer *buffer)
{
	wl_buffer_destroy(buffer);
}


void
draw_frame()
{
	draw_rect(win.canvas, 0, 0, win.width, win.height, 0xff00ff00);
}


void
surface_configure(void *data, struct xdg_surface *surface, uint32_t serial)
{
	xdg_surface_ack_configure(surface, serial);

	fprintf(stderr, "configure\n");

	if (win.canvas != 0) {
		free_drw(win.canvas);
	}
	win.canvas = create_drw(state.shm, win.width, win.height);

	draw_frame();
	wl_surface_attach(win.surface.wl, win.canvas->buffer, 0, 0);
	wl_surface_damage_buffer(win.surface.wl, 0, 0, win.width, win.height);
	wl_surface_commit(win.surface.wl);
}


void
toplevel_configure(void *data, struct xdg_toplevel *toplevel, int32_t width, int32_t height, struct wl_array *states)
{
	if (width == 0 || height == 0) {
		win.width = 800;
		win.height = 600;
	} else {
		win.width = width;
		win.height = height;
	}
}


void
toplevel_close(void *data, struct xdg_toplevel *toplevel)
{
	running = 0;
}


void
wm_base_ping(void *data, struct xdg_wm_base *wm_base, uint32_t serial)
{
	xdg_wm_base_pong(wm_base, serial);
}


void
registry_global(void *data, struct wl_registry *registry, uint32_t name, const char *interface, uint32_t version)
{
	match_then_bind(state.shm, wl_shm_interface, 1)
	or_match match_then_bind(state.compositor, wl_compositor_interface, 4)
	or_match match_then_bind(state.wm_base, xdg_wm_base_interface, 1)
	/* TODO: or_match match_then_bind(state.seat, wl_seat_interface, 7)
		wl_seat_add_listener(state.seat, &seat_listener, &state);*/
	end_match
}


void
registry_global_remove(void *data, struct wl_registry *registry, uint32_t name)
{
	/* TODO */
}


int main()
{
	state.display = wl_display_connect(0);
	state.registry = wl_display_get_registry(state.display);
	wl_registry_add_listener(state.registry, &registry_listener, &state);
	wl_display_roundtrip(state.display);

	xdg_wm_base_add_listener(state.wm_base, &wm_base_listener, &state);
	wl_display_roundtrip(state.display);

	win.surface.wl = wl_compositor_create_surface(state.compositor);
	win.surface.xdg = xdg_wm_base_get_xdg_surface(state.wm_base, win.surface.wl);
	xdg_surface_add_listener(win.surface.xdg, &surface_listener, &win);
	win.surface.toplevel = xdg_surface_get_toplevel(win.surface.xdg);
	xdg_toplevel_add_listener(win.surface.toplevel, &toplevel_listener, &win);
	xdg_toplevel_set_title(win.surface.toplevel, "swt");
	wl_surface_commit(win.surface.wl);

	while (wl_display_dispatch(state.display) && running) {
	}

	wl_display_disconnect(state.display);

	return 0;
}