const coral = @import("coral");

const kym = @import("kym");

const ona = @import("ona");

const transform2d_typename = @typeName(ona.gfx.Transform2D);

fn bind_canvas(environment: *kym.vm.Environment, canvas: *ona.gfx.Canvas) !void {
	const object = try environment.new(.{});

	defer environment.release(object);

	const sprite_creator = try environment.new(.{
		.userinfo = @ptrToInt(canvas),

		.behavior = &.{
			.caller = struct {
				fn call(context: kym.vm.Object.CallContext) kym.vm.RuntimeError!kym.vm.Value {
					try context.check(context.arguments.len == 2, "2 arguments expected");

					const transform = context.arguments[0].object;

					try context.check(transform.userinfo == @ptrToInt(transform2d_typename), "`transform2d` expected");

					_ = try @intToPtr(*ona.gfx.Canvas, context.object.userinfo).create_sprite(
						coral.io.bytes_to(ona.gfx.Transform2D, transform.userdata).?);

					return .nil;
				}
			}.call,
		},
	});

	defer environment.release(sprite_creator);

	try environment.raw_set(object, "create_sprite", sprite_creator.as_value());
	try environment.global_set("canvas", object.as_value());
}

// fn bind_transform_2d(environment: *kym.Environment) !*kym.Object {
// 	const allocator = environment.allocator();
// 	const transform_2d = try allocator.allocate_one(ona.gfx.Transform2D);

// 	errdefer allocator.deallocate(transform_2d);

// 	const object = try environment.new(@ptrToInt(transform_2d), .{
// 		.destructor = struct {
// 			fn destruct() void {
// 				allocator.deallocate(transform_2d);
// 			}
// 		}.destruct,
// 	});

// 	defer environment.release(object);

// 	try environment.set_field(environment.globals(), object);
// }

pub fn main() anyerror!void {
	return ona.App.run(anyerror, start);
}

fn start(app: *ona.App) anyerror!void {
	var kym_env = try kym.vm.Environment.init(ona.allocator, .{
		.stack_max = 256,
		.calls_max = 256,
	});

	defer kym_env.deinit();

	try bind_canvas(&kym_env, app.canvas());

	{
		const index_path = "index.kym";
		const index_file = try app.data_fs().open_readable(index_path);

		defer if (!index_file.close()) ona.log_error(&.{.{.string = "failed to close "}, .{.string = index_path}});

		const index_size = (try app.data_fs().query(index_path)).size;
		const index_allocation = try coral.io.allocate_many(u8, index_size, ona.allocator);

		defer coral.io.deallocate(ona.allocator, index_allocation);

		var index_buffer = coral.buffer.Fixed{.data = index_allocation[0 .. index_size]};

		{
			var stream_buffer = [_]u8{0} ** 1024;

			if ((try coral.io.stream(index_buffer.as_writer(), index_file.as_reader(), &stream_buffer)) != index_size)
				return error.IoUnavailable;
		}

		{
			const index_script = try kym_env.new_script(.{
				.name = index_path,
				.data = index_buffer.data
			});

			defer kym_env.release(index_script);

			_ = try kym_env.call(index_script, &.{});
		}
	}

	while (app.poll()) {
		app.present();
	}
}