#include "Gedeng/DirectionalLight.h"
#include "Gedeng/Input.h"
#include "Gedeng/Logger.h"
#include "Gedeng/ObjMesh.h"
#include "Gedeng/ParticleSystem.h"
#include "Gedeng/QuadMesh.h"
#include "Gedeng/Shader.h"
#include "Gedeng/TextLabel.h"
#include "Gedeng/Vector3.h"
#include <GLFW/glfw3.h>
#define GEDENG_MAIN
#include <Gedeng.h>

// For Debugging
unsigned int quadVAO = 0;
unsigned int quadVBO;
void renderQuad() {
    if (quadVAO == 0) {
        float quadVertices[] = {
            // positions        // texture Coords
            -1.0f, 1.0f, 0.0f, 0.0f, 1.0f, -1.0f, -1.0f, 0.0f, 0.0f, 0.0f,
            1.0f,  1.0f, 0.0f, 1.0f, 1.0f, 1.0f,  -1.0f, 0.0f, 1.0f, 0.0f,
        };
        // setup plane VAO
        glGenVertexArrays(1, &quadVAO);
        glGenBuffers(1, &quadVBO);
        glBindVertexArray(quadVAO);
        glBindBuffer(GL_ARRAY_BUFFER, quadVBO);
        glBufferData(GL_ARRAY_BUFFER, sizeof(quadVertices), &quadVertices, GL_STATIC_DRAW);
        glEnableVertexAttribArray(0);
        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void *)0);
        glEnableVertexAttribArray(1);
        glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void *)(3 * sizeof(float)));
    }
    glBindVertexArray(quadVAO);
    glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
    glBindVertexArray(0);
}

class ShadowApp : public Gedeng::Application {
  public:
    ShadowApp(unsigned long ms_per_update, unsigned int window_size_x, unsigned int window_size_y,
              Gedeng::String window_name)
        : Application(ms_per_update, window_size_x, window_size_y, window_name), particle_interval(0.2),
          number_of_steps(10.0), number_of_refinement_steps(10.0), bump_depth(0.1),
          render_shader(Gedeng::Shader("Shader/bump.vs", "Shader/bump.fs")),
          debug_shader(Gedeng::Shader("Shader/depth-debug.vs", "Shader/depth-debug.fs")),
          camera(Gedeng::FPSCamera(90, 1920, 1080, 0.1, 1000.0)),
          albedo("Resources/Textures/PavingStones/PavingStones070_2K_Color.jpg", Gedeng::Texture::Settings()),
          bump("Resources/Textures/PavingStones/PavingStones070_2K_Displacement.jpg", Gedeng::Texture::Settings()),
          normal("Resources/Textures/PavingStones/PavingStones070_2K_Normal.jpg", Gedeng::Texture::Settings()),
          particle_tex1("Resources/Textures/Particles/circle.png", Gedeng::Texture::Settings()),
          particle_tex2("Resources/Textures/Particles/magic.png", Gedeng::Texture::Settings()),
          particle_tex3("Resources/Textures/Particles/smoke.png", Gedeng::Texture::Settings()),
          quad_mesh(Gedeng::QuadMesh(10.0)), light(glm::vec3(0.57735, -0.57735, 0.57735)),
          monkey_mesh("Resources/Meshes/Monkey.obj", Gedeng::ObjMesh::Settings()) {
        particles.set_position(glm::vec3(0.0f, 0.0f, -10.0f));
        particles.set_velocity(glm::vec3(-2, 4, -2), glm::vec3(2, 6, 2));
        particles.set_gravity(glm::vec3(0, -4, 0));
        particles.set_color(glm::vec3(0.0f, 0.5f, 1.0f));
        particles.set_lifetime(1.0f, 1.5f);
        particles.set_size(0.1);
        particles.set_interval(particle_interval);
        particles.set_number_of_particles(1);
        particles.set_textures(&particle_tex1, &particle_tex2, &particle_tex3);

        camera.translate(glm::vec3(0.0, 2.0, 1.0));
        // camera.rotate(30, glm::vec3(1.0, 0.0, 0.0));

        monkey_mesh.translate(glm::vec3(2.0, 3.0, -2.0));
    }

    ~ShadowApp() = default;

    void fixed_update(double delta) override {
        camera.update(delta);

        if (Gedeng::Input::is_mouse_down(GLFW_MOUSE_BUTTON_LEFT))
            particles.set_position(camera.get_view_ray().get_plane_collision().collision_position);

        if (Gedeng::Input::is_key_down(GLFW_KEY_2)) particle_interval = fmax(particle_interval + 0.1 * delta, 0.02);
        if (Gedeng::Input::is_key_down(GLFW_KEY_1)) particle_interval = fmax(particle_interval - 0.1 * delta, 0.02);

        particles.set_interval(particle_interval);
    }

    void dynamic_update(double delta) override {
        // Shadows
        light.clear_shadows();
        light.render_shadow(monkey_mesh);
        light.render_shadow(quad_mesh);

        glViewport(0, 0, 1920, 1080);
        glClearColor(0.1, 0.1f, 0.1, 1.0f);
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

        render_shader.use();

        // Camera
        render_shader.setMat4("projection", camera.get_projection());
        render_shader.setMat4("view", camera.get_view());
        render_shader.setVec3("viewPos", camera.get_translation());

        // Lighting
        light.set_in_shader(render_shader);

        render_shader.setFloat("number_of_steps", glm::max(0.0f, number_of_steps));
        render_shader.setFloat("number_of_refinement_steps", glm::max(0.0f, number_of_refinement_steps));
        render_shader.setFloat("bump_depth", glm::max(0.0f, bump_depth));

        // Textures
        albedo.bind_to(0);
        normal.bind_to(1);
        bump.bind_to(2);
        light.bind_depth_map_to(3);

        // Quad which is rendered onto
        quad_mesh.render(render_shader);

        // Particles
        particles.set_camera(camera);
        particles.update(delta);
        particles.render();

        // Props
        render_shader.use();
        monkey_mesh.render(render_shader);

        /*         // Render the light's depth map to a quad for debugging
                debug_shader.use();
                light.bind_depth_map_to(0);
                renderQuad(); */
    }

  private:
    float particle_interval;

    float number_of_steps;
    float number_of_refinement_steps;
    float bump_depth;

    Gedeng::Shader render_shader;
    Gedeng::Shader debug_shader;

    Gedeng::VertexBuffer vertex_rectangle;

    Gedeng::FPSCamera camera;

    Gedeng::Texture albedo;
    Gedeng::Texture bump;
    Gedeng::Texture normal;

    Gedeng::Texture particle_tex1;
    Gedeng::Texture particle_tex2;
    Gedeng::Texture particle_tex3;

    Gedeng::QuadMesh quad_mesh;

    Gedeng::ParticleSystem particles;

    Gedeng::DirectionalLight light;
    Gedeng::ObjMesh monkey_mesh;
};

Gedeng::Application *Gedeng::create_application() {
    GG_CLIENT_INFO("Creating Application");
    return new ShadowApp(20, 1920, 1080, String("Parallax Demo"));
}