//  SPDX-License-Identifier: MIT
//
//  EmulationStation Desktop Edition
//  SystemScreenSaver.cpp
//
//  Screensaver, supporting the following modes:
//  Dim, black, slideshow, video.
//

#include "SystemScreenSaver.h"

#if defined(_RPI_)
#include "components/VideoPlayerComponent.h"
#endif
#include "components/VideoVlcComponent.h"
#include "utils/FileSystemUtil.h"
#include "views/gamelist/IGameListView.h"
#include "views/ViewController.h"
#include "FileData.h"
#include "FileFilterIndex.h"
#include "Log.h"
#include "PowerSaver.h"
#include "Sound.h"
#include "SystemData.h"

#include <time.h>
#include <unordered_map>

#if defined(_WIN64)
#include <cstring>
#endif

#define FADE_TIME 300

SystemScreenSaver::SystemScreenSaver(
    Window* window)
    : mVideoScreensaver(nullptr),
    mImageScreensaver(nullptr),
    mWindow(window),
    mVideosCounted(false),
    mVideoCount(0),
    mImagesCounted(false),
    mImageCount(0),
    mState(STATE_INACTIVE),
    mOpacity(0.0f),
    mTimer(0),
    mSystemName(""),
    mGameName(""),
    mCurrentGame(nullptr),
    mStopBackgroundAudio(true)
{
    mWindow->setScreenSaver(this);
    std::string path = getTitleFolder();
    if (!Utils::FileSystem::exists(path))
        Utils::FileSystem::createDirectory(path);
    srand((unsigned int)time(nullptr));
    mVideoChangeTime = 30000;
}

SystemScreenSaver::~SystemScreenSaver()
{
    // Delete subtitle file, if it exists.
    remove(getTitlePath().c_str());
    mCurrentGame = nullptr;
    delete mVideoScreensaver;
    delete mImageScreensaver;
}

bool SystemScreenSaver::allowSleep()
{
    return ((mVideoScreensaver == nullptr) && (mImageScreensaver == nullptr));
}

bool SystemScreenSaver::isScreenSaverActive()
{
    return (mState != STATE_INACTIVE);
}

void SystemScreenSaver::startScreenSaver()
{
    std::string screensaver_behavior = Settings::getInstance()->getString("ScreenSaverBehavior");

    // Set mPreviousGame which will be used to avoid showing the same game again during
    // the random selection.
    if ((screensaver_behavior == "video" || screensaver_behavior == "slideshow") &&
            mCurrentGame != nullptr)
        mPreviousGame = mCurrentGame;

    if (!mVideoScreensaver && (screensaver_behavior == "video")) {
        // Configure to fade out the windows, skip fading if mode is set to Instant.
        mState =  PowerSaver::getMode() ==
                PowerSaver::INSTANT ? STATE_SCREENSAVER_ACTIVE : STATE_FADE_OUT_WINDOW;
        mVideoChangeTime = Settings::getInstance()->getInt("ScreenSaverSwapVideoTimeout");
        mOpacity = 0.0f;

        // Load a random video.
        std::string path = "";
        pickRandomVideo(path);

        int retry = 200;
        while (retry > 0 && ((path.empty() || !Utils::FileSystem::exists(path)) ||
                mCurrentGame == nullptr)) {
            retry--;
            pickRandomVideo(path);
        }

        if (!path.empty() && Utils::FileSystem::exists(path)) {
            #if defined(_RPI_)
            // Create the correct type of video component
            if (Settings::getInstance()->getBool("ScreenSaverOmxPlayer"))
                mVideoScreensaver = new VideoPlayerComponent(mWindow, getTitlePath());
            else
                mVideoScreensaver = new VideoVlcComponent(mWindow, getTitlePath());
            #else
            mVideoScreensaver = new VideoVlcComponent(mWindow, getTitlePath());
            #endif

            mVideoScreensaver->topWindow(true);
            mVideoScreensaver->setOrigin(0.5f, 0.5f);
            mVideoScreensaver->setPosition(Renderer::getScreenWidth() / 2.0f,
                    Renderer::getScreenHeight() / 2.0f);

            if (Settings::getInstance()->getBool("ScreenSaverStretchVideos"))
                mVideoScreensaver->setResize(static_cast<float>(Renderer::getScreenWidth()),
                        static_cast<float>(Renderer::getScreenHeight()));
            else
                mVideoScreensaver->setMaxSize(static_cast<float>(Renderer::getScreenWidth()),
                        static_cast<float>(Renderer::getScreenHeight()));

            mVideoScreensaver->setVideo(path);
            mVideoScreensaver->setScreensaverMode(true);
            mVideoScreensaver->onShow();
            PowerSaver::runningScreenSaver(true);
            mTimer = 0;
            return;
        }
    }
    else if (screensaver_behavior == "slideshow") {
        // Configure to fade out the windows, skip fading if mode is set to Instant.
        mState =  PowerSaver::getMode() ==
                PowerSaver::INSTANT ? STATE_SCREENSAVER_ACTIVE : STATE_FADE_OUT_WINDOW;
        mVideoChangeTime = Settings::getInstance()->getInt("ScreenSaverSwapImageTimeout");
        mOpacity = 0.0f;

        // Load a random image.
        std::string path = "";
        if (Settings::getInstance()->getBool("SlideshowScreenSaverCustomImageSource")) {
            pickRandomCustomImage(path);
            // Custom images are not tied to the game list.
            mCurrentGame = nullptr;
        }
        else {
            pickRandomGameListImage(path);
        }

        if (!mImageScreensaver)
            mImageScreensaver = new ImageComponent(mWindow, false, false);

        mTimer = 0;

        mImageScreensaver->setImage(path);
        mImageScreensaver->setOrigin(0.5f, 0.5f);
        mImageScreensaver->setPosition(Renderer::getScreenWidth() / 2.0f,
                Renderer::getScreenHeight() / 2.0f);

        if (Settings::getInstance()->getBool("ScreenSaverStretchImages"))
            mImageScreensaver->setResize(static_cast<float>(Renderer::getScreenWidth()),
                    static_cast<float>(Renderer::getScreenHeight()));
        else
            mImageScreensaver->setMaxSize(static_cast<float>(Renderer::getScreenWidth()),
                    static_cast<float>(Renderer::getScreenHeight()));

        std::string bg_audio_file = Settings::getInstance()->
                getString("SlideshowScreenSaverBackgroundAudioFile");
        if ((!mBackgroundAudio) && (bg_audio_file != "")) {
            if (Utils::FileSystem::exists(bg_audio_file)) {
                // Pause PowerSaver so that the background audio keeps playing.
                PowerSaver::pause();
                mBackgroundAudio = Sound::get(bg_audio_file);
                mBackgroundAudio->play();
            }
        }

        PowerSaver::runningScreenSaver(true);
        mTimer = 0;
        return;
    }
    // No videos. Just use a standard screensaver.
    mState = STATE_SCREENSAVER_ACTIVE;
    mCurrentGame = nullptr;
}

void SystemScreenSaver::stopScreenSaver()
{
    if ((mBackgroundAudio) && (mStopBackgroundAudio)) {
        mBackgroundAudio->stop();
        mBackgroundAudio.reset();
        // If we were playing audio, we paused PowerSaver.
        PowerSaver::resume();
    }

    // So that we stop the background audio next time, unless we're restarting the screensaver.
    mStopBackgroundAudio = true;

    delete mVideoScreensaver;
    mVideoScreensaver = nullptr;
    delete mImageScreensaver;
    mImageScreensaver = nullptr;

    // We need this to loop through different videos.
    mState = STATE_INACTIVE;
    PowerSaver::runningScreenSaver(false);
}

void SystemScreenSaver::renderScreenSaver()
{
    std::string screensaver_behavior = Settings::getInstance()->getString("ScreenSaverBehavior");
    if (mVideoScreensaver && screensaver_behavior == "video") {
        // Render black background.
        Renderer::setMatrix(Transform4x4f::Identity());
        Renderer::drawRect(0.0f, 0.0f, Renderer::getScreenWidth(),
                Renderer::getScreenHeight(), 0x000000FF, 0x000000FF);

        // Only render the video if the state requires it.
        if (static_cast<int>(mState) >= STATE_FADE_IN_VIDEO) {
            Transform4x4f transform = Transform4x4f::Identity();
            mVideoScreensaver->render(transform);
        }
    }
    else if (mImageScreensaver && screensaver_behavior == "slideshow") {
        // Render black background.
        Renderer::setMatrix(Transform4x4f::Identity());
        Renderer::drawRect(0.0f, 0.0f, Renderer::getScreenWidth(),
                Renderer::getScreenHeight(), 0x000000FF, 0x000000FF);

        // Only render the video if the state requires it.
        if ((int)mState >= STATE_FADE_IN_VIDEO) {
            if (mImageScreensaver->hasImage()) {
                mImageScreensaver->setOpacity(255 - static_cast<unsigned char>(mOpacity * 255));

                Transform4x4f transform = Transform4x4f::Identity();
                mImageScreensaver->render(transform);
            }
        }

        // Check if we need to restart the background audio.
        if ((mBackgroundAudio) && (Settings::getInstance()->
                getString("SlideshowScreenSaverBackgroundAudioFile") != "")) {
            if (!mBackgroundAudio->isPlaying())
                mBackgroundAudio->play();
        }
    }
    else if (mState != STATE_INACTIVE) {
        #if !defined(USE_OPENGL_21)
        Renderer::setMatrix(Transform4x4f::Identity());
        unsigned char color = screensaver_behavior == "dim" ? 0x000000A0 : 0x000000FF;
        Renderer::drawRect(0.0f, 0.0f, Renderer::getScreenWidth(),
                Renderer::getScreenHeight(), color, color);
        #endif
    }
}

unsigned long SystemScreenSaver::countGameListNodes(const char *nodeName)
{
    unsigned long nodeCount = 0;
    std::vector<SystemData*>::const_iterator it;
    for (it = SystemData::sSystemVector.cbegin();
            it != SystemData::sSystemVector.cend(); ++it) {
        // We only want nodes from game systems that are not collections.
        if (!(*it)->isGameSystem() || (*it)->isCollection())
            continue;

        FileData* rootFileData = (*it)->getRootFolder();

        FileType type = GAME;
        std::vector<FileData*> allFiles = rootFileData->getFilesRecursive(type, true);
        std::vector<FileData*>::const_iterator itf;  // Declare an iterator to a vector of strings.

        for (itf=allFiles.cbegin() ; itf < allFiles.cend(); itf++) {
            if ((strcmp(nodeName, "video") == 0 && (*itf)->getVideoPath() != "") ||
                    (strcmp(nodeName, "image") == 0 && (*itf)->getImagePath() != ""))
                nodeCount++;
        }
    }
    return nodeCount;
}

void SystemScreenSaver::countVideos()
{
    if (!mVideosCounted) {
        mVideoCount = countGameListNodes("video");
        mVideosCounted = true;
    }
}

void SystemScreenSaver::countImages()
{
    if (!mImagesCounted) {
        mImageCount = countGameListNodes("image");
        mImagesCounted = true;
    }
}

void SystemScreenSaver::pickGameListNode(unsigned long index,
        const char *nodeName, std::string& path)
{
    std::vector<SystemData*>::const_iterator it;
    for (it = SystemData::sSystemVector.cbegin();
            it != SystemData::sSystemVector.cend(); ++it) {
        // We only want nodes from game systems that are not collections.
        if (!(*it)->isGameSystem() || (*it)->isCollection())
            continue;

        FileData* rootFileData = (*it)->getRootFolder();

        FileType type = GAME;
        std::vector<FileData*> allFiles = rootFileData->getFilesRecursive(type, true);
        std::vector<FileData*>::const_iterator itf;  // Declare an iterator to a vector of strings.

        for (itf=allFiles.cbegin() ; itf < allFiles.cend(); itf++) {
            if ((strcmp(nodeName, "video") == 0 && (*itf)->getVideoPath() != "") ||
                    (strcmp(nodeName, "image") == 0 && (*itf)->getImagePath() != "")) {
                if (index-- == 0) {
                    // We have it.
                    path = "";
                    if (strcmp(nodeName, "video") == 0)
                        path = (*itf)->getVideoPath();
                    else if (strcmp(nodeName, "image") == 0)
                        path = (*itf)->getImagePath();
                    mSystemName = (*it)->getFullName();
                    mGameName = (*itf)->getName();
                    mCurrentGame = (*itf);

                    // End of getting FileData.
                    #if defined(_RPI_)
                    if (Settings::getInstance()->getString("ScreenSaverGameInfo") != "never")
                        writeSubtitle(mGameName.c_str(), mSystemName.c_str(),
                                (Settings::getInstance()->getString("ScreenSaverGameInfo") ==
                                "always"));
                    #endif
                    return;
                }
            }
        }
    }
}

void SystemScreenSaver::pickRandomVideo(std::string& path)
{
    countVideos();
    mCurrentGame = nullptr;

    if (mVideoCount < 2)
        mPreviousGame = nullptr;

    // If there are more than 1 videos available, keep trying until the same game is
    // not shown again.
    if (mVideoCount > 0) {
        do {
            int video = static_cast<int>((static_cast<float>(rand()) /
                    static_cast<float>(RAND_MAX)) * static_cast<float>(mVideoCount));
            pickGameListNode(video, "video", path);
        }
        while (mPreviousGame && mCurrentGame == mPreviousGame);
    }
}

void SystemScreenSaver::pickRandomGameListImage(std::string& path)
{
    countImages();
    mCurrentGame = nullptr;

    if (mImageCount < 2)
        mPreviousGame = nullptr;

    // If there are more than 1 images available, keep trying until the same game is
    // not shown again.
    if (mImageCount > 0) {
        do {
            int image = static_cast<int>((static_cast<float>(rand()) /
                    static_cast<float>(RAND_MAX)) * static_cast<float>(mImageCount));
            pickGameListNode(image, "image", path);
        }
        while (mPreviousGame && mCurrentGame == mPreviousGame);
    }
}

void SystemScreenSaver::pickRandomCustomImage(std::string& path)
{
    std::string imageDir = Settings::getInstance()->getString("SlideshowScreenSaverImageDir");

    if ((imageDir != "") && (Utils::FileSystem::exists(imageDir))) {
        std::string imageFilter = Settings::getInstance()->
                getString("SlideshowScreenSaverImageFilter");
        std::vector<std::string> matchingFiles;
        Utils::FileSystem::stringList dirContent = Utils::FileSystem::getDirContent(
                imageDir, Settings::getInstance()->getBool("SlideshowScreenSaverRecurse"));

        for (Utils::FileSystem::stringList::const_iterator it = dirContent.cbegin();
                it != dirContent.cend(); ++it) {
            if (Utils::FileSystem::isRegularFile(*it)) {
                // If the image filter is empty, or the file extension is in the filter
                // string, add it to the matching files list.
                if ((imageFilter.length() <= 0) || (imageFilter.find(
                        Utils::FileSystem::getExtension(*it)) != std::string::npos))
                    matchingFiles.push_back(*it);
            }
        }

        int fileCount = static_cast<int>(matchingFiles.size());
        if (fileCount > 0) {
            // Get a random index in the range 0 to fileCount (exclusive).
            int randomIndex = rand() % fileCount;
            path = matchingFiles[randomIndex];
        }
        else {
            LOG(LogError) << "Slideshow Screensaver - No image files found\n";
        }
    }
    else {
        LOG(LogError) << "Slideshow Screensaver - Image directory does not exist: " <<
                imageDir << "\n";
    }
}

void SystemScreenSaver::update(int deltaTime)
{
    // Use this to update the fade value for the current fade stage.
    if (mState == STATE_FADE_OUT_WINDOW) {
        mOpacity += static_cast<float>(deltaTime) / FADE_TIME;
        if (mOpacity >= 1.0f) {
            mOpacity = 1.0f;

            // Update to the next state.
            mState = STATE_FADE_IN_VIDEO;
        }
    }
    else if (mState == STATE_FADE_IN_VIDEO) {
        mOpacity -= static_cast<float>(deltaTime) / FADE_TIME;
        if (mOpacity <= 0.0f) {
            mOpacity = 0.0f;
            // Update to the next state.
            mState = STATE_SCREENSAVER_ACTIVE;
        }
    }
    else if (mState == STATE_SCREENSAVER_ACTIVE) {
        // Update the timer that swaps the videos.
        mTimer += deltaTime;
        if (mTimer > mVideoChangeTime)
            nextGame();
    }

    // If we have a loaded video then update it.
    if (mVideoScreensaver)
        mVideoScreensaver->update(deltaTime);
    if (mImageScreensaver)
        mImageScreensaver->update(deltaTime);
}

void SystemScreenSaver::nextGame() {
    mStopBackgroundAudio = false;
    stopScreenSaver();
    startScreenSaver();
    mState = STATE_SCREENSAVER_ACTIVE;
}

FileData* SystemScreenSaver::getCurrentGame()
{
    return mCurrentGame;
}

void SystemScreenSaver::launchGame()
{
    if (mCurrentGame != nullptr) {
        // Launching game
        ViewController::get()->goToGameList(mCurrentGame->getSystem());
        IGameListView* view = ViewController::get()->
                getGameListView(mCurrentGame->getSystem()).get();
        view->setCursor(mCurrentGame);
        ViewController::get()->resetMovingCamera();
        ViewController::get()->launch(mCurrentGame);
    }
}