/* A complete CPU-rendered window. Build instructions: docs/getting-started.md. */
#include <yasl/yasl.h>

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

struct app {
    bool running;
    bool failed;
    bool smoke_test;
};

static void quit(void *ud)
{
    ((struct app *)ud)->running = false;
}

static void lost(void *ud)
{
    struct app *app = ud;
    app->failed = true;
    app->running = false;
}

static void close_window(struct yasl_surface *surface, void *ud)
{
    (void)surface;
    quit(ud);
}

static void configure(struct yasl_surface *surface, struct yasl_geometry geometry, void *ud)
{
    (void)geometry;
    (void)ud;
    yasl_surface_schedule_redraw(surface);
}

static void draw(struct yasl_surface *surface, struct yasl_frame *frame, void *ud)
{
    struct app *app = ud;
    size_t count = (size_t)frame->target.size.x * frame->target.size.y;
    for (size_t i = 0; i < count; i++)
        frame->target.pixels[i] = 0xff306090; /* Opaque premultiplied ARGB. */

    struct yasl_damage_list damage = {.n = -1};
    if (!yasl_surface_present(surface, &frame->target, &damage)) {
        fprintf(stderr, "Could not present the draw target\n");
        app->failed = true;
        app->running = false;
    }
    if (app->smoke_test) app->running = false;
}

int main(int argc, char **argv)
{
    struct app app = {.running = true};
    if (argc == 2 && strcmp(argv[1], "--smoke-test") == 0)
        app.smoke_test = true;
    else if (argc != 1) {
        fprintf(stderr, "Usage: %s [--smoke-test]\n", argv[0]);
        return 1;
    }

    struct yasl_display_cbs display_callbacks = {.quit = quit, .lost = lost};
    struct yasl_display_spec display_spec = {
        .app_id = "org.example.hello",
        .cbs = &display_callbacks,
        .ud = &app,
    };
    struct yasl_display *display = yasl_display_open(NULL, &display_spec);
    if (!display) {
        perror("yasl_display_open");
        return 1;
    }
    struct yasl_window_cbs callbacks = {
        .draw = draw, .configure = configure, .close = close_window,
    };
    struct yasl_window_spec spec = {
        .title = "Hello YASL", .size = {640, 480},
        .cbs = &callbacks, .ud = &app,
    };
    struct yasl_surface *surface = yasl_surface_create_toplevel(display, &spec);
    if (!surface) {
        perror("yasl_surface_create_toplevel");
        yasl_display_close(display);
        return 1;
    }
    yasl_surface_schedule_redraw(surface);

    while (app.running) {
        if (yasl_display_dispatch(display, -1) < 0) {
            perror("yasl_display_dispatch");
            app.failed = true;
            break;
        }
        /* Drain even unused input so queued events do not cause a busy loop. */
        struct yasl_input_event event;
        while (yasl_surface_input_poll(surface, &event)) {}
        if (app.running) yasl_display_flush(display);
    }
    yasl_surface_destroy(surface);
    yasl_display_close(display);
    return app.failed ? 1 : 0;
}