#include "../include/Video.hpp"
#include <mpv/client.h>
#include <mpv/opengl_cb.h>
#include <clocale>

#include <SFML/Config.hpp>

#if defined(SFML_SYSTEM_WINDOWS)
    #ifdef _MSC_VER
        #include <windows.h>
    #endif
    #include <GL/gl.h>
    #include <GL/glx.h>
#elif defined(SFML_SYSTEM_LINUX) || defined(SFML_SYSTEM_FREEBSD)
    #if defined(SFML_OPENGL_ES)
        #include <GLES/gl.h>
        #include <GLES/glext.h>
    #else
        #include <GL/gl.h>
    #endif
    #include <GL/glx.h>
    #define glGetProcAddress glXGetProcAddress
#elif defined(SFML_SYSTEM_MACOS)
    #include <OpenGL/gl.h>
#elif defined (SFML_SYSTEM_IOS)
    #include <OpenGLES/ES1/gl.h>
    #include <OpenGLES/ES1/glext.h>
#elif defined (SFML_SYSTEM_ANDROID)
    #include <GLES/gl.h>
    #include <GLES/glext.h>
    // We're not using OpenGL ES 2+ yet, but we can use the sRGB extension
    #include <GLES2/gl2ext.h>
#endif

using namespace std;

namespace dchat
{
    void* getProcAddressMpv(void *funcContext, const char *name)
    {
        return (void*)glGetProcAddress((const GLubyte*)name);
    }
    
    void onMpvRedraw(void *rawVideo)
    {
        Video *video = (Video*)rawVideo;
        ++video->redrawCounter;
    }
    
    Video::Video(unsigned int width, unsigned int height, const char *file, bool loop) : 
        redrawCounter(0),
        context(sf::ContextSettings(), width, height),
        mpv(nullptr),
        mpvGl(nullptr),
        textureBuffer(new sf::Uint8[width * height * 4]) // 4 = red, green, blue and alpha
    {
        context.setActive(true);
        
        if(!texture.create(width, height))
            throw VideoInitializationException("Failed to create texture for video");
        texture.setSmooth(true);
        
        // mpv_create requires LC_NUMERIC to be set to "C" for some reason, see mpv_create documentation
        std::setlocale(LC_NUMERIC, "C");
        mpv = mpv_create();
        if(!mpv)
            throw VideoInitializationException("Failed to create mpv handle");
        
        if(mpv_initialize(mpv) < 0)
            throw VideoInitializationException("Failed to initialize mpv");
        
        mpv_set_option_string(mpv, "vo", "opengl-cb");
        mpv_set_option_string(mpv, "hwdec", "auto");
        if(loop)
            mpv_set_option_string(mpv, "loop", "inf");
        mpvGl = (mpv_opengl_cb_context*)mpv_get_sub_api(mpv, MPV_SUB_API_OPENGL_CB);
        if(!mpvGl)
            throw VideoInitializationException("Failed to initialize mpv opengl render context");
        
        mpv_opengl_cb_set_update_callback(mpvGl, onMpvRedraw, this);
        if(mpv_opengl_cb_init_gl(mpvGl, nullptr, getProcAddressMpv, nullptr) < 0)
            throw VideoInitializationException("Failed to initialize mpv gl callback func");
        
        renderThread = thread([this, width, height]()
        {
            context.setActive(true);
            while(true)
            {
                while(true)
                {
                    mpv_event *mpvEvent = mpv_wait_event(mpv, 0.0);
                    if(mpvEvent->event_id == MPV_EVENT_NONE)
                        break;
                    else if(mpvEvent->event_id == MPV_EVENT_SHUTDOWN)
                        break;
                }
                
                if(redrawCounter > 0)
                {
                    --redrawCounter;
                    context.setActive(true);
                    renderMutex.lock();
                    //mpv_render_context_render(mpvGl, params);
                    mpv_opengl_cb_draw(mpvGl, 0, width, height);
                    glReadPixels(0, 0, width, height, GL_RGBA, GL_UNSIGNED_BYTE, textureBuffer);
                    texture.update(textureBuffer);
                    sprite.setTexture(texture, true);
                    mpv_opengl_cb_report_flip(mpvGl, 0);
                    renderMutex.unlock();
                }
                this_thread::sleep_for(chrono::milliseconds(10));
            }
        });
        renderThread.detach();
        
        const char *cmd[] = { "loadfile", file, nullptr };
        mpv_command(mpv, cmd);
        context.setActive(false);
    }
    
    Video::~Video()
    {
        lock_guard<mutex> lock(renderMutex);
        context.setActive(true);
        if(mpvGl)
            mpv_opengl_cb_set_update_callback(mpvGl, nullptr, nullptr);
        
        delete[] textureBuffer;
        mpv_opengl_cb_uninit_gl(mpvGl);
        mpv_destroy(mpv);
        if(renderThread.joinable())
            renderThread.join();
    }
    
    void Video::setPosition(float x, float y)
    {
        sprite.setPosition(x, y);
    }
    
    void Video::draw(sf::RenderWindow &window)
    {
        lock_guard<mutex> lock(renderMutex);
        window.draw(sprite);
    }
}