#ifndef SHADER_H
#define SHADER_H

#include "opengl.h"
#include <unordered_map>

class Shader {
public:
    enum VertexAttributes {
        ATTRIBUTE_POSITION = 0,
        ATTRIBUTE_NORMAL,
        ATTRIBUTE_COLOR,
        ATTRIBUTE_UV,
    };

    bool bind();
    void unbind();

    void compile();
    void destroy();

    const GLchar **get_vertex_shader_source();
    void set_vertex_shader_source(const GLchar **source);

    const GLchar **get_fragment_shader_source();
    void set_fragment_shader_source(const GLchar **source);

    void print_shader_errors(const GLuint p_program, const char *name);
    void print_program_errors(const GLuint p_program);

    Shader();
    ~Shader();

    GLuint vertex_shader;
    GLuint fragment_shader;
    GLuint program;

    static Shader * current_shader;

protected:
    const GLchar **vertex_shader_source;
    const GLchar **fragment_shader_source;
};

class ShaderCache {
public:
    static ShaderCache *get_singleton();

    Shader *get_shader(const int id);
    void add_shader(const int id, Shader *shader);

    ShaderCache();
    ~ShaderCache();

protected:
    std::unordered_map<int, Shader *> shaders;
};


#endif // SHADER_H