#pragma once
#include <string>
#include <vector>
#include <memory>
#include <GL/glew.h>
#include <functional>
#include "glm/gtc/type_ptr.hpp"

#include "Material.h"
#include "Light.h"
#include "SceneContext.h"
#include "Loader.h"

enum ShaderFlags
{
	NO_UNIFORM = 0,
	KD_FLAG = 1,
	KA_FLAG = 2,
	KS_FLAG = 4,
	SHINE_FLAG = 8,
	MVP_FLAG = 16,
	NORMAL_MAT_FLAG = 32,
	MODELVIEW_FLAG = 64,
	LIGHTS_FLAG = 128,
};

class Shader
{
public:
	Shader() {};
	Shader(const std::string vtx_name, const std::string frag_name);
	~Shader();

	int uniformFlags = KD_FLAG | KA_FLAG | KS_FLAG | SHINE_FLAG | MVP_FLAG | NORMAL_MAT_FLAG | MODELVIEW_FLAG | LIGHTS_FLAG;
	Material mat;
	Light::LightType light_type = Light::LightType::BASE;

	void enable();
	void disable();

	
public:
	void setUniforms(SceneContext ctx);
	void addUniform(const std::string name, glm::vec3 data)
	{
		_program.use(); glUniform3fv(_program.addUniform(name), 1, glm::value_ptr(data)); ; _program.disable();
	}
	void addUniform(const std::string name, int data)
	{
		_program.use(); glUniform1i(_program.addUniform(name), data);  _program.disable();
	}
	void addUniform(const std::string name, float data)
	{
		_program.use(); glUniform1fv(_program.addUniform(name), 1, &data);  _program.disable();
	}

private:
	void setMaterial(SceneContext ctx);
	void setCamera(SceneContext ctx);
	void setLights(SceneContext ctx);

private:
	ShaderProgram _program;
};