#include "v4k.h"

int SKY_DIR = 0;
const char *SKY_DIRS[] = {
    "cubemaps/bridge3/",
    "cubemaps/colors/",
    "cubemaps/colors2/",
    "hdr/Tokyo_BigSight_1k.hdr",
};

int OBJ_MDL = 0;
const char *OBJ_MDLS[] = {
    "meshes/ShadowsTest.obj",
    "meshes/sphere.obj",
    "meshes/suzanne.obj",
    "meshes/gazebo.obj",
};

int main(int argc, char** argv) {
    window_create(85, WINDOW_MSAA8);
    // window_fps_unlock();

    camera_t cam = camera(); {
        cam.position = vec3(0, 7.5, 15);
        cam.pitch = -15;
        cam.yaw = -90;
        camera_fps(&cam, 0, 0);
    }
    skybox_t sky = {0};
    model_t mdl = {0};
    shadowmap_t sm = {0};
    light_t lit = light(); {
        lit.type = LIGHT_POINT;
        lit.cast_shadows = true;
        // lit.shadow_distance = 1.0f;
        lit.falloff.linear = 2.0f;
    }
    light_t lit2 = light(); {
        lit2.type = LIGHT_POINT;
        lit2.cast_shadows = true;
        lit2.diffuse = vec3(1, 0.7, 0.8);
        // lit2.shadow_distance = 1.0f;
        lit2.falloff.linear = 2.0f;
    }
    light_t lit3 = light(); {
        lit3.type = LIGHT_SPOT;
        lit3.cast_shadows = true;
        // lit3.shadow_distance = 5.0f;
        lit3.diffuse = vec3(1, 0.7, 0.8);
    }
    light_t lit4 = light(); {
        lit4.type = LIGHT_DIRECTIONAL;
        lit4.cast_shadows = true;
        // lit4.shadow_distance = 2000.0f;
        lit4.diffuse = vec3(1, 0.7, 0.8);
    }

    array(light_t) point_lights = 0;
    array_push(point_lights, lit);
    array_push(point_lights, lit2);
    
    array(light_t) spot_lights = 0;
    array_push(spot_lights, lit3);

    array(light_t) directional_lights = 0;
    array_push(directional_lights, lit4);

    array(light_t) all_lights = 0;
    array_push(all_lights, lit);
    array_push(all_lights, lit2);
    array_push(all_lights, lit3);
    array_push(all_lights, lit4);

    bool initialized = 0;
    bool must_reload = 0;

    while( window_swap()) {
        if (input_down(KEY_ESC)) break;
        // reloading
        if( must_reload ) {
            must_reload = 0;
            skybox_destroy(&sky);
            model_destroy(mdl);
            initialized = 0;
        }
        if( !initialized ) {
            initialized = 1;
            sky = skybox(flag("--mie") ? 0 : SKY_DIRS[SKY_DIR], 0);
            sm = shadowmap(512, 4096);
            // sm.blur_pcf = 1; 
            mdl = model(OBJ_MDLS[OBJ_MDL], 0);
            shader_bind(mdl.program);
            cubemap_sh_shader(&sky.cubemap);
        }

        // fps camera
        bool active = ui_active() || ui_hover() || gizmo_active() ? false : input(MOUSE_L) || input(MOUSE_M) || input(MOUSE_R);
        window_cursor( !active );

        if( active ) cam.speed = clampf(cam.speed + input_diff(MOUSE_W) / 10, 0.05f, 5.0f);
        vec2 mouse = scale2(vec2(input_diff(MOUSE_X), -input_diff(MOUSE_Y)), 0.2f * active);
        vec3 wasdec = scale3(vec3(input(KEY_D)-input(KEY_A),input(KEY_E)-input(KEY_C),input(KEY_W)-input(KEY_S)), cam.speed);
        camera_moveby(&cam, wasdec);
        camera_fps(&cam, mouse.x,mouse.y);

        enum {
            POINT, SPOT, DIR, ALL
        };
        static unsigned mode = ALL;

        if (input_down(KEY_1)) mode = POINT;
        if (input_down(KEY_2)) mode = SPOT;
        if (input_down(KEY_3)) mode = DIR;
        if (input_down(KEY_4)) mode = ALL;
        light_t *lights = 0;
        switch (mode) {
            case POINT: lights = point_lights; break;
            case SPOT: lights = spot_lights; break;
            case DIR: lights = directional_lights; break;
            case ALL: lights = all_lights; break;
        }

        // Animate light
        if (mode == POINT) {
            lights[0].pos = vec3(0, 5.5, 1);
            lights[0].pos.x += sinf(window_time()*2)*4.5f;
            lights[0].pos.y += cosf(window_time()*2)*1.0;
            lights[0].pos.z += cosf(window_time()*2)*6.0;

            lights[1].pos = vec3(0, 7.5, 1);
            lights[1].pos.x += sinf(window_time()*4)*4.5f;
            lights[1].pos.y += cosf(window_time()*4)*1.0;
            lights[1].pos.z += cosf(window_time()*4)*6.0;
        }

        static bool camera_spot = true;
        if (input_down(KEY_SPACE)) camera_spot = !camera_spot;
        if (mode == SPOT && camera_spot) {
            lights[0].pos = cam.position;
            lights[0].dir = cam.lookdir;
        }

        if (mode == DIR) {
            lights[0].pos = cam.position;
            lights[0].dir = vec3(1,-1,-1);
        }

        if (mode == ALL) {
            lights[0].pos = vec3(0, 5.5, 1);
            lights[0].pos.x += sinf(window_time()*2)*4.5f;
            lights[0].pos.y += cosf(window_time()*2)*1.0;
            lights[0].pos.z += cosf(window_time()*2)*6.0;

            lights[1].pos = vec3(0, 7.5, 1);
            lights[1].pos.x += sinf(window_time()*4)*4.5f;
            lights[1].pos.y += cosf(window_time()*4)*1.0;
            lights[1].pos.z += cosf(window_time()*4)*6.0;

            lights[2].pos = cam.position;
            lights[2].dir = cam.lookdir;

            lights[3].dir = vec3(1,-1,-1);
        }

        // Render shadowmap
        shadowmap_begin(&sm);
        {
            for (int i = 0; i < array_count(lights); i++) {
                while (shadowmap_step(&sm)) {
                    shadowmap_light(&sm, &lights[i], cam.proj, cam.view);
                    model_render(mdl, cam.proj, cam.view, mdl.pivot, 0);
                }
            }
        }
        shadowmap_end(&sm);

        // render
        mat44 mvp; multiply44x2(mvp, cam.proj, cam.view);
        {
            skybox_render(&sky, cam.proj, cam.view);
            
            shader_bind(mdl.program);
            light_update(array_count(lights), lights);

            model_shadow(&mdl, &sm);
            model_render(mdl, cam.proj, cam.view, mdl.pivot, 0);
        }

        if( ui_panel("Scene", 0)) {
            if( ui_list("Skybox", SKY_DIRS, countof(SKY_DIRS), &SKY_DIR) ) {
                must_reload = 1;
            }
            if( ui_list("Model", OBJ_MDLS, countof(OBJ_MDLS), &OBJ_MDL) ) {
                must_reload = 1;
            }
            ui_panel_end();
        }
    }
}