#ifndef SHADER_H
#define SHADER_H

#include "gl.h"

class GLBaseShader {
	friend class GLShaderProgram;

	protected:
		void shader_source(const char *filename);
		void shader_source(std::string& filename);
		unsigned int shader;
	public:
		GLBaseShader(GLenum);
		~GLBaseShader();
};

class GLVertexShader : public GLBaseShader {
	public:
		GLVertexShader() : GLBaseShader(GL_VERTEX_SHADER) {};
		GLVertexShader(const char *s) : GLBaseShader(GL_VERTEX_SHADER) { shader_source(s); };
		GLVertexShader(std::string& s) : GLBaseShader(GL_VERTEX_SHADER) { shader_source(s); };
};

class GLFragmentShader : public GLBaseShader {
	public:
		GLFragmentShader() : GLBaseShader(GL_FRAGMENT_SHADER) {};
		GLFragmentShader(const char *s) : GLBaseShader(GL_FRAGMENT_SHADER) { shader_source(s); };
		GLFragmentShader(std::string& s) : GLBaseShader(GL_FRAGMENT_SHADER) { shader_source(s); };
};

class GLShaderProgram {
	protected:
		unsigned int program;
	public:
		GLShaderProgram();
		~GLShaderProgram();

		void attach(GLBaseShader&);
		void detach(GLBaseShader&);
		void link();
		void use();

		GLuint get_program();
};

#endif