#include "Renderer.hpp"

#include <glrage_gl/Shader.hpp>
#include <glrage_gl/Utils.hpp>

// #include "openssl/md5.h"
#include <glrage_util/StringUtils.hpp>

namespace glrage {
namespace ddraw {

Renderer::Renderer()
    : m_surfaceBuffer(GL_ARRAY_BUFFER)
{
    // configure buffer
    m_surfaceBuffer.bind();
    GLfloat verts[] = {
        0.0, 0.0, 1.0, 0.0, 0.0, 1.0, 0.0, 1.0, 1.0, 0.0, 1.0, 1.0};
    m_surfaceBuffer.data(sizeof(verts), verts, GL_STATIC_DRAW);

    m_surfaceFormat.bind();
    m_surfaceFormat.attribute(0, 2, GL_FLOAT, GL_FALSE, 0, 0);

    // configure sampler
    // TODO: make me configurable
    GLint filterMethodEnum = GL_LINEAR; // GL_NEAREST

    m_sampler.bind(0);
    m_sampler.parameteri(GL_TEXTURE_MAG_FILTER, filterMethodEnum);
    m_sampler.parameteri(GL_TEXTURE_MIN_FILTER, filterMethodEnum);

    // configure shaders
    std::string basePath = m_context.getBasePath();
    m_program.attach(gl::Shader(GL_VERTEX_SHADER)
                         .fromFile(basePath + "\\shaders\\ddraw.vsh"));
    m_program.attach(gl::Shader(GL_FRAGMENT_SHADER)
                         .fromFile(basePath + "\\shaders\\ddraw.fsh"));
    m_program.link();
    m_program.fragmentData("fragColor");

    gl::Utils::checkError(__FUNCTION__);
}

void Renderer::upload(DDSURFACEDESC& desc, std::vector<uint8_t>& data)
{
    uint32_t width = desc.dwWidth;
    uint32_t height = desc.dwHeight;
    uint8_t* bits = &data[0];
    GLenum tex_format = TEX_FORMAT;
    GLenum tex_type = TEX_TYPE;
    m_surfaceTexture.bind();

    // TODO: implement texture packs

    // update buffer if the size is unchanged, otherwise create a new one
    if (width != m_width || height != m_height) {
        m_width = width;
        m_height = height;
        glTexImage2D(GL_TEXTURE_2D,
            0,
            TEX_INTERNAL_FORMAT,
            m_width,
            m_height,
            0,
            tex_format,
            tex_type,
            bits);
    } else {
        glTexSubImage2D(GL_TEXTURE_2D,
            0,
            0,
            0,
            m_width,
            m_height,
            tex_format,
            tex_type,
            bits);
    }
}

void Renderer::render()
{
    m_program.bind();
    m_surfaceBuffer.bind();
    m_surfaceFormat.bind();
    m_surfaceTexture.bind();
    m_sampler.bind(0);

    GLboolean texture2d = glIsEnabled(GL_TEXTURE_2D);
    if (!texture2d) {
        glEnable(GL_TEXTURE_2D);
    }

    GLboolean blend = glIsEnabled(GL_BLEND);
    if (blend) {
        glDisable(GL_BLEND);
    }

    GLboolean depthTest = glIsEnabled(GL_DEPTH_TEST);
    if (depthTest) {
        glDisable(GL_DEPTH_TEST);
    }

    glDrawArrays(GL_TRIANGLES, 0, 6);

    if (!texture2d) {
        glDisable(GL_TEXTURE_2D);
    }

    if (blend) {
        glEnable(GL_BLEND);
    }

    if (depthTest) {
        glEnable(GL_DEPTH_TEST);
    }

    gl::Utils::checkError(__FUNCTION__);
}

} // namespace ddraw
} // namespace glrage