#include "Program.hpp"

#include <algorithm>
#include <stdexcept>
#include "texture.hpp"

#define CONTENT_DIR "content/"
#define SHADER_DIR CONTENT_DIR "shaders/"
#define TEXTURES_DIR CONTENT_DIR "textures/"

void Program::load(const std::vector<Shader*>& shaders) {
    ProgramID = glCreateProgram();

    for(auto shader : shaders) {
        glAttachShader(ProgramID, shader->getId());
    }
    glLinkProgram(ProgramID);

    // Check the program
    GLint result = GL_FALSE;
    int infoLogLength;
    glGetProgramiv(ProgramID, GL_LINK_STATUS, &result);
    glGetProgramiv(ProgramID, GL_INFO_LOG_LENGTH, &infoLogLength);
    if (infoLogLength > 0) {
        std::vector<char> errorMessage(infoLogLength + 1);
        glGetProgramInfoLog(ProgramID, infoLogLength, NULL, &errorMessage[0]);
        throw std::runtime_error(&errorMessage[0]);
    }

    for(auto shader : shaders) {
        glDetachShader(ProgramID, shader->getId());
        delete shader;
    }
}
Program::~Program() {
    glDeleteProgram(ProgramID);
}
Shader* Program::loadShader(GLenum type, const std::vector<std::string>& flags) {
    return new Shader(type, SHADER_DIR + getName() + "." + Shader::getExt(type), flags);
}

void Program::useIt() {
    glUseProgram(ProgramID);
}

GLuint Program::loadTexture(const std::string& name, bool linear) {
    return loadDDS(TEXTURES_DIR + name + ".dds", linear);
}
GLuint Program::loadTextureArray(const std::vector<std::string> &names, const std::string& suffix, float mipMapLOD) {

    std::vector<std::string> paths;
    std::transform(names.begin(), names.end(), std::back_inserter(paths),
                   [suffix](const std::string &name) -> std::string { return TEXTURES_DIR + name + suffix + ".dds"; });
    return loadDDSArray(paths, mipMapLOD);
}
GLuint Program::loadTextureCube(const std::string &name) {

    std::array<std::string, 6> faces {
        "right",
        "left",
        "top",
        "bottom",
        "front",
        "back"
    };
    std::array<std::string, 6> paths;
    std::transform(faces.begin(), faces.end(), paths.begin(),
                   [name](const std::string &face) -> std::string { return TEXTURES_DIR + name + ".cube." + face + ".dds"; });
    return loadDDSCube(paths);
}
GLuint Program::loadRawTexture(const std::string& name) {
    return loadBMP_custom(name.c_str());
}