#include "Shaders/ShaderProgram.h"
#include "GLObjects/WaveMesh.h"
#include "Audio/AudioPlayer.h"
#include "GLObjects/SpectralMesh.h"

#include <GLFW/glfw3.h>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>

#include <iostream>
#include <fstream>
#include <sstream>

glm::vec3 eye(0.0f, 0.0f, 4.0f), at(0.0f, 0.0f, 0.0f), up(0.0f, 1.0f, 0.0f);
glm::mat4 mView = glm::lookAt(eye, at, up);
glm::mat4 mProjection = glm::perspective(45.0f, 1.0f, -2.0f, 2.0f); //glm::perspective(45.0f, 1.0f, 2.0f, -2.0f);
bool wired = false;

void key_callback(GLFWwindow* window, int key, int scancode, int action, int mods)
{
	if (key == GLFW_KEY_M && action == GLFW_PRESS) {
		glPolygonMode(GL_FRONT_AND_BACK, wired ? GL_FILL : GL_LINE);
		wired = !wired;
	}
}

void _update_fps_counter (GLFWwindow* window) {
	static double previous_seconds = glfwGetTime ();
	static int frame_count;
	double current_seconds = glfwGetTime ();
	double elapsed_seconds = current_seconds - previous_seconds;
	if (elapsed_seconds > 0.25) {
		previous_seconds = current_seconds;
		double fps = (double)frame_count / elapsed_seconds;
		char tmp[128];
		sprintf (tmp, "opengl @ fps: %.2f", fps);
		glfwSetWindowTitle (window, tmp);
		frame_count = 0;
	}
	frame_count++;
}

int main() {
	glfwInit();
	glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
	glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
	glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
	glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
	glfwWindowHint(GLFW_RESIZABLE, GL_FALSE);
	glfwWindowHint (GLFW_SAMPLES, 4);

	GLFWwindow* window = glfwCreateWindow(1024, 1024, "OpenGL", nullptr, nullptr); // Windowed
	glfwMakeContextCurrent(window);
	glfwSetKeyCallback(window, key_callback);

	glewExperimental = GL_TRUE;
	GLenum err = glewInit();
	if(err != GLEW_OK) {
		std::cout << "GLEW error: " << err << ": " << glewGetErrorString(err) << std::endl;
	}

	ShaderProgram program("../shaders/vertex.glsl", "../shaders/fragment.glsl");
	program.use();

//	WaveMesh mesh(&program, 128);
//	mesh.create();

	SpectralMesh mesh(&program, 256);
	mesh.create();

	GLint view = glGetUniformLocation(program, "mView");
	glUniformMatrix4fv(view, 1, GL_FALSE, glm::value_ptr(mView));
	GLint projection = glGetUniformLocation(program, "mProjection");
	glUniformMatrix4fv(projection, 1, GL_FALSE, glm::value_ptr(mProjection));

//	glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
	glDepthFunc(GL_LEQUAL);
	glEnable(GL_DEPTH_TEST);

	AudioPlayer player("/home/selim/dl/euphoria.wav");
	player.setStreamListener([&mesh](void* data, std::size_t framesCount){
		mesh.addLine((float*)data);
	});
	player.play();

	float azimuth = 0.0f, elevation = 0.0f, scale = 1.0f;

	while(!glfwWindowShouldClose(window)) {
		_update_fps_counter (window);
		glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

		if(glfwGetKey(window, GLFW_KEY_LEFT) == GLFW_PRESS) {
			azimuth -= 0.05f;
		} else if(glfwGetKey(window, GLFW_KEY_RIGHT) == GLFW_PRESS) {
			azimuth += 0.05f;
		} else if(glfwGetKey(window, GLFW_KEY_UP) == GLFW_PRESS) {
			elevation -= 0.05f;
		} else if(glfwGetKey(window, GLFW_KEY_DOWN) == GLFW_PRESS) {
			elevation += 0.05f;
		} else if(glfwGetKey(window, GLFW_KEY_KP_ADD) == GLFW_PRESS) {
			scale += 0.05f;
		} else if(glfwGetKey(window, GLFW_KEY_KP_SUBTRACT) == GLFW_PRESS) {
			scale -= 0.05f;
		}

//		double time = glfwGetTime();
//		float shift = (float)fmod(time, 2*3.1415926);
//		mesh.setShift(shift*2);
		mesh.update();


		mesh.scale(glm::vec3(scale, scale, scale));
		mesh.rotate(glm::vec3(elevation, azimuth, 0));
		mesh.draw();

		glfwPollEvents();
		glfwSwapBuffers(window);
	}

	glfwTerminate();
}