#include <fstream>
#include <glad/glad.h>
#include <glm/gtc/type_ptr.hpp>
#include <iostream>
#include <shader.hpp>
#include <sstream>
#include <string>

/*pub*/
Shader::Shader(const char *vertexPath, const char *fragmentPath) {
  std::string vertexCode, fragmentCode;
  std::ifstream vShaderFile, fShaderFile;

  vShaderFile.exceptions(std::ifstream::failbit | std::ifstream::badbit);
  fShaderFile.exceptions(std::ifstream::failbit | std::ifstream::badbit);
  try {
    vShaderFile.open(vertexPath);
    fShaderFile.open(fragmentPath);
    std::stringstream vShaderStream, fShaderStream;

    vShaderStream << vShaderFile.rdbuf();
    fShaderStream << fShaderFile.rdbuf();

    vShaderFile.close();
    fShaderFile.close();

    vertexCode = vShaderStream.str();
    fragmentCode = fShaderStream.str();
  } catch (std::ifstream::failure &e) {
    std::cout << "ERROR::SHADER::FILE_NOT_SUCCESSFULLY_READ: " << e.what()
              << std::endl;
  }
  this->ID = shaderProgramCMPL(vertexCode.c_str(), fragmentCode.c_str());
}

Shader::~Shader() { glDeleteProgram(ID); }

void Shader::use() { glUseProgram(ID); }

void Shader::setInt(const std::string &name, int value) {
  glUniform1i(glGetUniformLocation(ID, name.c_str()), value);
}

void Shader::setFloat(const std::string &name, float value) {
  glUniform1f(glGetUniformLocation(ID, name.c_str()), value);
}

void Shader::setVec3(const std::string &name, glm::vec3 value) {
  glUniform3fv(glGetUniformLocation(ID, name.c_str()), 1,
               glm::value_ptr(value));
}

void Shader::setMat4(const std::string &name, glm::mat4 value) {
  glUniformMatrix4fv(glGetUniformLocation(ID, name.c_str()), 1, GL_FALSE,
                     glm::value_ptr(value));
}

/*priv*/
unsigned int Shader::shaderCMPL(GLenum type, const char *src) {
  unsigned int shader;
  shader = glCreateShader(type);
  glShaderSource(shader, 1, &src, NULL);
  glCompileShader(shader);
  return shader;
}

void Shader::shaderERR(unsigned int shader) {
  int success;
  char infoLog[512];
  glGetShaderiv(shader, GL_COMPILE_STATUS, &success);

  if (!success) {
    glGetShaderInfoLog(shader, 512, NULL, infoLog);
    std::cout << "ERROR::SHADER::COMPILATION_FAILED\n" << infoLog << std::endl;
  }
}

unsigned int Shader::shaderProgramCMPL(const char *vertexSource,
                                       const char *fragmentSource) {
  unsigned int vertexShader;
  vertexShader = shaderCMPL(GL_VERTEX_SHADER, vertexSource);
  shaderERR(vertexShader);

  unsigned int fragmentShader;
  fragmentShader = shaderCMPL(GL_FRAGMENT_SHADER, fragmentSource);
  shaderERR(fragmentShader);

  unsigned int shaderProgram;
  shaderProgram = glCreateProgram();

  glAttachShader(shaderProgram, vertexShader);
  glAttachShader(shaderProgram, fragmentShader);
  glLinkProgram(shaderProgram);
  shaderProgramERR(shaderProgram);
  glDeleteShader(vertexShader);
  glDeleteShader(fragmentShader);

  return shaderProgram;
}

void Shader::shaderProgramERR(unsigned int shaderProgram) {
  int success;
  char infoLog[512];
  glGetProgramiv(shaderProgram, GL_LINK_STATUS, &success);

  if (!success) {
    glGetProgramInfoLog(shaderProgram, 512, NULL, infoLog);
    std::cout << "ERROR::SHADER::PROGRAM::FAILED\n" << infoLog << std::endl;
  }
}