#include "sokol/sokol_app.h"
#include "sokol/sokol_gfx.h"
#include "sokol/sokol_log.h"
#include "sokol/sokol_glue.h"
#include "flecs.h"
#include "app.h"
#include "scene_manager.h"
#include "scenes/menu_scene.h"
#include "scenes/game_scene.h"
#include "shaders/triangle-sapp.glsl.h"
#include "ecs_core.h"

static struct {
    sg_pipeline pipeline;
    sg_bindings bind;
    sg_pass_action pass_action;
} state;

static ecs_world_t* ecs_world;
static app_context_t app_ctx;

static void draw_square(float x, float y, float size, float r, float g, float b, float a) {
    const float s = size;
    float z = 0.5f;
    // Two triangles (6 vertices), each vertex: pos xyz + color rgba
    float v[6 * 7] = {
        // tri 1
        x - s, y - s, z,  r, g, b, a,
        x + s, y - s, z,  r, g, b, a,
        x + s, y + s, z,  r, g, b, a,
        // tri 2
        x - s, y - s, z,  r, g, b, a,
        x + s, y + s, z,  r, g, b, a,
        x - s, y + s, z,  r, g, b, a,
    };
    sg_range rng = { .ptr = v, .size = sizeof(v) };
    sg_update_buffer(state.bind.vertex_buffers[0], &rng);
    sg_apply_pipeline(state.pipeline);
    sg_apply_bindings(&state.bind);
    sg_draw(0, 6, 1);
}

static void init(void) {
    ecs_world = ecs_init();
    sg_setup(&(sg_desc){
        .environment = sglue_environment(),
        .logger.func = slog_func,
    });

    // Create a dynamic vertex buffer large enough for one quad (6 vertices)
    state.bind.vertex_buffers[0] = sg_make_buffer(&(sg_buffer_desc){
        .usage = { .vertex_buffer = true, .stream_update = true },
        .size = (size_t)(sizeof(float) * 6 * 7),
    });

    state.pipeline = sg_make_pipeline(&(sg_pipeline_desc){
        .shader = sg_make_shader(triangle_shader_desc(sg_query_backend())),
        .layout = {
            .attrs = {
                [ATTR_triangle_position].format = SG_VERTEXFORMAT_FLOAT3,
                [ATTR_triangle_color0].format = SG_VERTEXFORMAT_FLOAT4
            }
        },
    });

    state.pass_action = (sg_pass_action) {
        .colors[0] = { .load_action=SG_LOADACTION_CLEAR, .clear_value={0.0f, 0.0f, 0.0f, 1.0f } }
    };

    app_ctx.world = ecs_world;
    app_ctx.pass_action = &state.pass_action;
    ecs_core_set_draw_api(draw_square);

    scene_manager_init(&app_ctx);
    scene_manager_set(&MenuScene);
}

void frame(void) {
    float dt = (float)sapp_frame_duration();
    sg_begin_pass(&(sg_pass){ .action = state.pass_action, .swapchain = sglue_swapchain() });
    scene_manager_update(dt);
    scene_manager_render();
    sg_end_pass();
    sg_commit();
}

void cleanup(void) {
    scene_manager_shutdown();
    sg_shutdown();
    ecs_fini(ecs_world);
}

void event(const sapp_event* ev) {
    scene_manager_event(ev);
}

sapp_desc sokol_main(int argc, char* argv[]) {
    (void)argc; (void)argv;
    return (sapp_desc){
        .init_cb = init,
        .frame_cb = frame,
        .cleanup_cb = cleanup,
        .event_cb = event,
        .width = 640,
        .height = 480,
        .window_title = "Triangle",
        .high_dpi = true,
        .html5 = {
            .canvas_resize = false, // track CSS size; sokol scales to devicePixelRatio
        },
        .icon.sokol_default = true,
        .logger.func = slog_func,
    };
}