#pragma once
#ifndef SHADER_H
#define SHADER_H

#include <string>

#include <glad/glad.h>
#include <glm/glm.hpp>
#include <glm/gtc/type_ptr.hpp>


// General purpose shader object. Compiles from file, generates
// compile/link-time error messages and hosts several utility 
// functions for easy management.
class Shader
{
public:
    // state
    unsigned int ID;
    // constructor
    Shader() { }
    // sets the current shader as active
    Shader& Use();
    // compiles the shader from given source code
    void    Compile(const char* vertexSource, const char* fragmentSource, const char* geometrySource = nullptr); // note: geometry source code is optional 
    // utility functions
    void    SetFloat(const char* name, float value, bool useShader = false);
    void    SetInteger(const char* name, int value, bool useShader = false);
    void    SetVector2f(const char* name, float x, float y, bool useShader = false);
    void    SetVector2f(const char* name, const glm::vec2& value, bool useShader = false);
    void    SetVector3f(const char* name, float x, float y, float z, bool useShader = false);
    void    SetVector3f(const char* name, const glm::vec3& value, bool useShader = false);
    void    SetVector4f(const char* name, float x, float y, float z, float w, bool useShader = false);
    void    SetVector4f(const char* name, const glm::vec4& value, bool useShader = false);
    void    SetMatrix4(const char* name, const glm::mat4& matrix, bool useShader = false);
private:
    // checks if compilation or linking failed and if so, print the error logs
    void    checkCompileErrors(unsigned int object, std::string type);
};

#endif