#include <sokol/sokol_app.h>
#include <sokol/sokol_gfx.h>
#include <sokol/sokol_log.h>
#include <sokol/sokol_glue.h>
#include <math.h>

#include <shaders/shader.glsl.h>

static struct {
    sg_pipeline pip;
    sg_bindings bind;
    sg_pass_action pass_action;
    vs_params_t vs_params;
    int index;
} state;

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

    state.vs_params.rotation = 0.0f;
    state.index = 0;

    float vertices[] = {
         0.0f,  0.5f, 0.5f,     1.0f, 0.0f, 0.0f, 1.0f,
        -0.5f, -0.5f, 0.5f,     0.0f, 1.0f, 0.0f, 1.0f,
         0.5f, -0.5f, 0.5f,     0.0f, 0.0f, 1.0f, 1.0f,
    };
    state.bind.vertex_buffers[0] = sg_make_buffer(&(sg_buffer_desc){
        .data = SG_RANGE(vertices),
        .label = "triangle-vertices"
    });

    sg_shader shd = sg_make_shader(triangle_shader_desc(sg_query_backend()));

    state.pip = sg_make_pipeline(&(sg_pipeline_desc){
        .shader = shd,
        .layout = {
            .attrs = {
                [ATTR_vs_position].format = SG_VERTEXFORMAT_FLOAT3,
                [ATTR_vs_color0].format = SG_VERTEXFORMAT_FLOAT4
            }
        },
        .label = "triangle-pipeline",
        .cull_mode = SG_CULLMODE_BACK,
        .face_winding = SG_FACEWINDING_CCW,
        .sample_count = 1,
    });

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

void frame(void) {
    sg_begin_pass(&(sg_pass){ .action = state.pass_action, .swapchain = sglue_swapchain() });
    sg_apply_pipeline(state.pip);
    sg_apply_bindings(&state.bind);
    state.vs_params.rotation = sin(++state.index * 0.05);
    sg_apply_uniforms(SG_SHADERSTAGE_VS, 0, &SG_RANGE(state.vs_params));
    sg_draw(0, 3, 1);
    sg_end_pass();
    sg_commit();
}

void cleanup(void) {
    sg_shutdown();
}

sapp_desc sokol_main(int argc, char* argv[]) {
    (void)argc; (void)argv;
    return (sapp_desc){
        .init_cb = init,
        .frame_cb = frame,
        .cleanup_cb = cleanup,
        .width = 640,
        .height = 480,
        #ifdef SOKOL_GLCORE
        .window_title = "Gear (GLCORE)",
        #elif SOKOL_D3D11
        .window_title = "Gear (D3D11)",
        #elif SOKOL_METAL
        .window_title = "Gear (Metal)",
        #endif
        .icon.sokol_default = true,
        .logger.func = slog_func,
    };
}