#include <GL/glew.h>
#include <GLFW/glfw3.h>
#include <cglm/cglm.h>

#define SKR_BACKEND_API 0    // opengl
#define SKR_BACKEND_WINDOW 0 // glfw
#include <skr/skr.h>

SkrCamera* g_skr_camera = SkrDefaultFPSCamera;

int main(void) {
	SkrState state = SkrInit(&(SkrWindow){
	        .Title = "Hello SKR",
	        .Width = 800,
	        .Height = 600,
	});

	glewInit();

	SkrCaptureCursor(&state);

	SkrInitCamera(&state, skr_fps_camera_vert);

	float vertices[] = {
	        -0.5f, -0.5f, -0.5f, 0.0f,  0.0f,  0.5f,  -0.5f, -0.5f,
	        1.0f,  0.0f,  0.5f,  0.5f,  -0.5f, 1.0f,  1.0f,  0.5f,
	        0.5f,  -0.5f, 1.0f,  1.0f,  -0.5f, 0.5f,  -0.5f, 0.0f,
	        1.0f,  -0.5f, -0.5f, -0.5f, 0.0f,  0.0f,

	        -0.5f, -0.5f, 0.5f,  0.0f,  0.0f,  0.5f,  -0.5f, 0.5f,
	        1.0f,  0.0f,  0.5f,  0.5f,  0.5f,  1.0f,  1.0f,  0.5f,
	        0.5f,  0.5f,  1.0f,  1.0f,  -0.5f, 0.5f,  0.5f,  0.0f,
	        1.0f,  -0.5f, -0.5f, 0.5f,  0.0f,  0.0f,

	        -0.5f, 0.5f,  0.5f,  1.0f,  0.0f,  -0.5f, 0.5f,  -0.5f,
	        1.0f,  1.0f,  -0.5f, -0.5f, -0.5f, 0.0f,  1.0f,  -0.5f,
	        -0.5f, -0.5f, 0.0f,  1.0f,  -0.5f, -0.5f, 0.5f,  0.0f,
	        0.0f,  -0.5f, 0.5f,  0.5f,  1.0f,  0.0f,

	        0.5f,  0.5f,  0.5f,  1.0f,  0.0f,  0.5f,  0.5f,  -0.5f,
	        1.0f,  1.0f,  0.5f,  -0.5f, -0.5f, 0.0f,  1.0f,  0.5f,
	        -0.5f, -0.5f, 0.0f,  1.0f,  0.5f,  -0.5f, 0.5f,  0.0f,
	        0.0f,  0.5f,  0.5f,  0.5f,  1.0f,  0.0f,

	        -0.5f, -0.5f, -0.5f, 0.0f,  1.0f,  0.5f,  -0.5f, -0.5f,
	        1.0f,  1.0f,  0.5f,  -0.5f, 0.5f,  1.0f,  0.0f,  0.5f,
	        -0.5f, 0.5f,  1.0f,  0.0f,  -0.5f, -0.5f, 0.5f,  0.0f,
	        0.0f,  -0.5f, -0.5f, -0.5f, 0.0f,  1.0f,

	        -0.5f, 0.5f,  -0.5f, 0.0f,  1.0f,  0.5f,  0.5f,  -0.5f,
	        1.0f,  1.0f,  0.5f,  0.5f,  0.5f,  1.0f,  0.0f,  0.5f,
	        0.5f,  0.5f,  1.0f,  0.0f,  -0.5f, 0.5f,  0.5f,  0.0f,
	        0.0f,  -0.5f, 0.5f,  -0.5f, 0.0f,  1.0f};

	// world space positions of our cubes
	vec3 cubePositions[] = {{0.0f, 0.0f, 0.0f},    {2.0f, 5.0f, -15.0f},
	                        {-1.5f, -2.2f, -2.5f}, {-3.8f, -2.0f, -12.3f},
	                        {2.4f, -0.4f, -3.5f},  {-1.7f, 3.0f, -7.5f},
	                        {1.3f, -2.0f, -2.5f},  {1.5f, 2.0f, -2.5f},
	                        {1.5f, 0.2f, -1.5f},   {-1.3f, 1.0f, -1.5f}};

	SkrMesh mesh = {0};

	glGenVertexArrays(1, &mesh.VAO);
	glGenBuffers(1, &mesh.VBO);

	glBindVertexArray(mesh.VAO);

	glBindBuffer(GL_ARRAY_BUFFER, mesh.VBO);
	glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices,
	             GL_STATIC_DRAW);

	// position attribute
	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float),
	                      (void*)0);
	glEnableVertexAttribArray(0);
	// texture coord attribute
	glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float),
	                      (void*)(3 * sizeof(float)));
	glEnableVertexAttribArray(1);

	GLuint program = m_skr_gl_create_program_from_shaders(
	        (SkrShader[]){skr_fps_camera_vert}, 1);

	const char* paths[] = {"assets/container.jpg",
	                       "assets/awesomeface.png"};

	unsigned int textures[2];
	m_skr_gl_load_textures_2d_from_paths(paths, textures, 2);

	glUseProgram(program);

	while (!SkrWindowShouldClose(state.Window)) {
		glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

		glActiveTexture(GL_TEXTURE0);
		glBindTexture(GL_TEXTURE_2D, textures[0]);
		glActiveTexture(GL_TEXTURE1);
		glBindTexture(GL_TEXTURE_2D, textures[1]);

		m_skr_gl_shader_use(program);

		// Projection matrix
		mat4 projection;
		glm_perspective(glm_rad(g_skr_camera->FOV), 800.0f / 600.0f,
		                0.1f, 100.0f, projection);
		m_skr_gl_shader_set_mat4(program, "projection", projection);

		// View matrix (camera)
		vec3 center;
		glm_vec3_add(g_skr_camera->Position, g_skr_camera->Front,
		             center);
		mat4 view;
		glm_lookat(g_skr_camera->Position, center, g_skr_camera->Up,
		           view);
		m_skr_gl_shader_set_mat4(program, "view", view);

		// Draw all cubes
		glBindVertexArray(mesh.VAO);

		for (unsigned int i = 0; i < 10; i++) {
			mat4 model;
			glm_mat4_identity(model);
			glm_translate(model, cubePositions[i]);
			glm_rotate(model, glm_rad(20.0f * i),
			           (vec3){1.0f, 0.3f, 0.5f});
			m_skr_gl_shader_set_mat4(program, "model", model);

			glDrawArrays(GL_TRIANGLES, 0, 36);
		}

		glfwSwapBuffers(state.Window->Backend.Handler.GLFW);
		glfwPollEvents();
	}

	m_skr_free_textures_2d(textures, 2);
	SkrFinalize(&state);
	return 0;
}