#import "modules/std.sx";
#import "modules/sdl3.sx";
#import "modules/opengl.sx";
#import "modules/math";
#import "modules/stb.sx";
#import "ui";

WIDTH  :f32: 800;
HEIGHT :f32: 600;

save_snapshot :: (path: [:0]u8, w: s32, h: s32) {
    stride : s64 = w * 4;
    buf_size : s64 = stride * h;
    pixels : [*]u8 = xx context.allocator.alloc(buf_size);
    glReadPixels(0, 0, w, h, GL_RGBA, GL_UNSIGNED_BYTE, pixels);

    // Flip vertically (GL reads bottom-up, PNG expects top-down)
    row_buf : [*]u8 = xx context.allocator.alloc(stride);
    i : s32 = 0;
    while i < h / 2 {
        top : s64 = xx i * stride;
        bot : s64 = xx (h - 1 - i) * stride;
        memcpy(row_buf, @pixels[top], stride);
        memcpy(@pixels[top], @pixels[bot], stride);
        memcpy(@pixels[bot], row_buf, stride);
        i += 1;
    }

    stbi_write_png(path, w, h, 4, pixels, xx stride);
    out("Saved ");
    out(path);
    out("\n");
}

main :: () -> void {
    SDL_Init(SDL_INIT_VIDEO);

    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
    SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, SDL_GL_CONTEXT_FORWARD_COMPATIBLE_FLAG);
    SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
    SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);

    window := SDL_CreateWindow("SX UI Demo", xx WIDTH, xx HEIGHT, SDL_WINDOW_OPENGL);
    gl_ctx := SDL_GL_CreateContext(window);
    SDL_GL_MakeCurrent(window, gl_ctx);
    SDL_GL_SetSwapInterval(1);

    load_gl(SDL_GL_GetProcAddress);
    load_gl_ui(SDL_GL_GetProcAddress);

    // --- Build UI ---
    pipeline : UIPipeline = ---;
    pipeline.init(WIDTH, HEIGHT);

    // Create a simple layout: VStack with colored rects and a button
    root := VStack.{ spacing = 10.0, alignment = .center };

    header := RectView.{ color = COLOR_YELLOW, preferred_height = 80.0, corner_radius = 8.0 };
    root.add(xx header);

    btn := Button.{ label = "Click Me", font_size = 14.0, style = ButtonStyle.default(), on_tap = null };
    root.add(xx btn);

    body := HStack.{ spacing = 10.0, alignment = .center };

    left := RectView.{ color = COLOR_RED, preferred_width = 200.0, preferred_height = 300.0, corner_radius = 4.0 };
    body.add(xx left);

    right := RectView.{ color = COLOR_GREEN, preferred_width = 200.0, preferred_height = 300.0, corner_radius = 4.0 };
    body.add(xx right);

    root.add(xx body);

    footer := RectView.{ color = COLOR_DARK_GRAY, preferred_height = 60.0 };
    root.add(xx footer);

    pipeline.set_root(xx root);

    // --- Main loop ---
    running := true;
    sdl_event : SDL_Event = .none;

    while running {
        while SDL_PollEvent(sdl_event) {
            if sdl_event == {
                case .quit: running = false;
                case .key_up: (e) {
                    if e.key == {
                        case .escape: running = false;
                    }
                }
            }

            // Forward to UI
            ui_event := translate_sdl_event(@sdl_event);
            if ui_event.type != .none {
                pipeline.dispatch_event(@ui_event);
            }
        }

        glClearColor(0.12, 0.12, 0.15, 1.0);
        glClear(GL_COLOR_BUFFER_BIT);

        pipeline.tick();

        SDL_GL_SwapWindow(window);
    }

    // Re-render one frame for snapshot (back buffer is stale after swap)
    glClearColor(0.12, 0.12, 0.15, 1.0);
    glClear(GL_COLOR_BUFFER_BIT);
    pipeline.tick();
    save_snapshot("goldens/last_frame.png", xx WIDTH, xx HEIGHT);

    SDL_GL_DestroyContext(gl_ctx);
    SDL_DestroyWindow(window);
    SDL_Quit();
}