//HEADER FILE
#ifndef CS5400_PROGRAM
#define CS5400_PROGRAM

#include <memory>

#include "Shader.hpp"

namespace cs5400
{
  class Program
  {
  public:
    Program(
      std::shared_ptr<VertexShader> vertex_
     ,std::shared_ptr<FragmentShader> fragment_)
    :handle(glCreateProgram())
    ,vertex(vertex_)
    ,fragment(fragment_)
    {}
    GLuint getHandle(){return handle;}
    ~Program()
    {
      //glDeleteProgram(handle);
    }
  private:
    GLuint handle;
    std::shared_ptr<VertexShader> vertex;
    std::shared_ptr<FragmentShader> fragment;
  };
  
  std::shared_ptr<Program> make_program(std::shared_ptr<VertexShader> vertex,std::shared_ptr<FragmentShader> fragment);
}

#endif


//SOURCE FILE

#include "Program.hpp"

  
std::shared_ptr<cs5400::Program> cs5400::make_program
(
  std::shared_ptr<cs5400::VertexShader> vertex
 ,std::shared_ptr<cs5400::FragmentShader> fragment  
)
{
  GLint link_ok = GL_FALSE;
  auto program = std::make_shared<Program>(vertex,fragment);
  glAttachShader(program->getHandle(), vertex->getHandle());
  glAttachShader(program->getHandle(), fragment->getHandle());
  glLinkProgram(program->getHandle());
  glGetProgramiv(program->getHandle(), GL_LINK_STATUS, &link_ok);
  if (!link_ok) 
  {
    throw std::runtime_error("Could not link shader program.");
  }
  return program;
}