//    This file is part of Motion Watch.

//    Motion Watch is free software: you can redistribute it and/or modify
//    it under the terms of the GNU General Public License as published by
//    the Free Software Foundation, either version 3 of the License, or
//    (at your option) any later version.

//    Motion Watch is distributed in the hope that it will be useful,
//    but WITHOUT ANY WARRANTY; without even the implied warranty of
//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//    GNU General Public License for more details.

#include "camera.h"

Camera::Camera(QObject *parent) : QObject(parent) {}

int Camera::start(const QStringList &args)
{
    if (rdConf(getParam("-c", args), &shared))
    {   
        QDir().mkpath(shared.outDir);
        QDir().mkpath(shared.tmpDir);

        QDir().mkpath(shared.outDir + "/events");
        QDir().mkpath(shared.tmpDir + "/live");
        QDir().mkpath(shared.tmpDir + "/logs");
        QDir().mkpath(shared.tmpDir + "/img");

        touch(shared.tmpDir + "/index.html");
        touch(shared.tmpDir + "/stream.html");
        touch(shared.tmpDir + "/stream.m3u8");

        QFile::link(shared.tmpDir + "/live",        shared.outDir + "/live");
        QFile::link(shared.tmpDir + "/logs",        shared.outDir + "/logs");
        QFile::link(shared.tmpDir + "/img",         shared.outDir + "/img");
        QFile::link(shared.tmpDir + "/index.html",  shared.outDir + "/index.html");
        QFile::link(shared.tmpDir + "/stream.html", shared.outDir + "/stream.html");
        QFile::link(shared.tmpDir + "/stream.m3u8", shared.outDir + "/stream.m3u8");
        QFile::link(shared.outDir + "/events",      shared.tmpDir + "/events");

        if (!QDir::setCurrent(shared.tmpDir))
        {
            QTextStream(stderr) << "err: failed to change/create the current working directory to camera folder: '" << shared.outDir << "' does it exists?" << Qt::endl;

            shared.retCode = ENOENT;
        }
        else
        {
            auto thr1 = new QThread(nullptr);
            auto thr2 = new QThread(nullptr);
            auto thr3 = new QThread(nullptr);
            auto thr4 = new QThread(nullptr);

            new RecLoop(&shared, thr1, nullptr);
            new Upkeep(&shared, thr2, nullptr);
            new EventLoop(&shared, thr3, nullptr);
            new DetectLoop(&shared, thr4, nullptr);

            thr1->start();
            thr2->start();
            thr3->start();
            thr4->start();
        }
    }

    return shared.retCode;
}

Loop::Loop(shared_t *sharedRes, QThread *thr, QObject *parent) : QObject(parent)
{
    shared    = sharedRes;
    heartBeat = 10;
    loopTimer = 0;

    connect(thr, &QThread::started, this, &Loop::init);

    moveToThread(thr);
}

void Loop::init()
{
    loopTimer = new QTimer(this);

    connect(loopTimer, &QTimer::timeout, this, &Loop::loopSlot);

    loopTimer->setSingleShot(false);
    loopTimer->start(heartBeat * 1000);

    loopSlot();
}

void Loop::loopSlot()
{
    if (!exec())
    {
        loopTimer->stop(); QCoreApplication::exit(shared->retCode);
    }
}

bool Loop::exec()
{
    if (loopTimer->interval() != heartBeat * 1000)
    {
        loopTimer->start(heartBeat * 1000);
    }

    return shared->retCode == 0;
}

RecLoop::RecLoop(shared_t *sharedRes, QThread *thr, QObject *parent) : Loop(sharedRes, thr, parent)
{
    recProc = 0;
    imgProc = 0;
}

void RecLoop::init()
{
    recProc = new QProcess(this);
    imgProc = new QProcess(this);

    connect(QCoreApplication::instance(), &QCoreApplication::aboutToQuit, this, &RecLoop::term);
    connect(recProc, &QProcess::readyReadStandardError, this, &RecLoop::rdProcErr);
    connect(imgProc, &QProcess::readyReadStandardError, this, &RecLoop::rdProcErr);

    Loop::init();
}

void RecLoop::updateCmd()
{
    QStringList recArgs;
    QStringList imgArgs;

    recArgs << "-hide_banner";
    recArgs << "-i" << shared->recordUrl;
    recArgs << "-strftime" << "1";
    recArgs << "-strftime_mkdir" << "1";
    recArgs << "-hls_segment_filename" << "live/" + QString(STRFTIME_FMT) + ".ts";
    recArgs << "-y";
    recArgs << "-vcodec" << "copy";
    recArgs << "-f" << "hls";
    recArgs << "-hls_time" << "2";
    recArgs << "-hls_list_size" << "1000";
    recArgs << "-hls_flags" << "append_list+omit_endlist";
    recArgs << "-rtsp_transport" << "tcp";
    recArgs << "-stimeout" << "3000";
    recArgs << "-t" << QString::number(heartBeat);
    recArgs << "stream.m3u8";

    imgArgs << "-hide_banner";
    imgArgs << "-i" << shared->recordUrl;
    imgArgs << "-strftime" << "1";
    imgArgs << "-strftime_mkdir" << "1";
    imgArgs << "-vf" << "fps=1,scale=320:240";
    imgArgs << "-rtsp_transport" << "tcp";
    imgArgs << "-stimeout" << "3000";
    imgArgs << "-t" << QString::number(heartBeat);
    imgArgs << "img/" + QString(STRFTIME_FMT) + ".bmp";

    recProc->setProgram("ffmpeg");
    recProc->setArguments(recArgs);

    imgProc->setProgram("ffmpeg");
    imgProc->setArguments(imgArgs);

    recLog("rec_args: " + recArgs.join(" "), shared);
    recLog("img_args: " + imgArgs.join(" "), shared);
}

void RecLoop::rdProcErr()
{
    procError("img", imgProc);
    procError("rec", recProc);
}

void RecLoop::term()
{
    recProc->kill();
    recProc->waitForFinished();

    imgProc->kill();
    imgProc->waitForFinished();
}

void RecLoop::procError(const QString &desc, QProcess *proc)
{
    if (proc->isOpen() && (proc->state() != QProcess::Running))
    {
        auto errBlob  = QString(proc->readAllStandardError());
        auto errLines = errBlob.split('\n');

        if (!errLines.isEmpty())
        {
            for (auto &&line : errLines)
            {
                recLog(desc + "_cmd_stderr: " + line, shared);
            }
        }
    }
}

bool RecLoop::exec()
{
    if ((imgProc->state() == QProcess::Running) || (recProc->state() == QProcess::Running))
    {
        term();
    }

    updateCmd();

    imgProc->start();
    recProc->start();

    return Loop::exec();
}

Upkeep::Upkeep(shared_t *sharedRes, QThread *thr, QObject *parent) : Loop(sharedRes, thr, parent) {}

bool Upkeep::exec()
{
    enforceMaxLogSize(QString("logs/") + REC_LOG_NAME, shared);
    enforceMaxLogSize(QString("logs/") + DET_LOG_NAME, shared);

    dumpLogs(QString("logs/") + REC_LOG_NAME, shared->recLog);
    dumpLogs(QString("logs/") + DET_LOG_NAME, shared->detLog);

    shared->logMutex.lock();
    shared->recLog.clear();
    shared->detLog.clear();
    shared->logMutex.unlock();

    initLogFrontPages();
    enforceMaxEvents(shared);
    enforceMaxImages();
    enforceMaxVids();

    genHTMLul(".", shared->camName, shared);

    genCSS(shared);
    genHTMLul(shared->buffPath, QString(APP_NAME) + " " + QString(APP_VER), shared);

    return Loop::exec();
}

EventLoop::EventLoop(shared_t *sharedRes, QThread *thr, QObject *parent) : Loop(sharedRes, thr, parent)
{
    heartBeat = 2;
    highScore = 0;
    cycles    = 0;
}

bool EventLoop::exec()
{
    if (!vidList.isEmpty())
    {
        vidList.removeDuplicates();

        if (vidList.size() > 1)
        {
            recLog("attempting write out of event: " + name, shared);

            if (wrOutVod())
            {
                genHTMLvod(name);

                QProcess    proc;
                QStringList args;

                args << "convert";
                args << imgPath;
                args << "events/" + name + ".jpg";

                proc.start("magick", args);
                proc.waitForFinished();
            }
        }

        cycles    = 0;
        highScore = 0;

        vidList.clear();
    }

    shared->recMutex.lock();

    QList<int> rmIndx;

    for (auto i = 0; i < shared->recList.size(); ++i)
    {
        auto event = &shared->recList[i];

        if (highScore < event->score)
        {
            name      = event->timeStamp.toString(DATETIME_FMT);
            imgPath   = event->imgPath;
            highScore = event->score;
        }

        if (event->queAge >= (shared->evMaxSecs / heartBeat))
        {
            auto maxSecs = shared->evMaxSecs / 2;
            // half the maxsecs value to get front-back half secs

            auto backFiles  = backwardFacingFiles("live", ".ts", event->timeStamp, maxSecs);
            auto frontFiles = forwardFacingFiles("live", ".ts", event->timeStamp, maxSecs);

            vidList.append(backFiles + frontFiles);
            rmIndx.append(i);
        }
        else
        {
            event->queAge += heartBeat;
        }
    }

    for (auto i : rmIndx)
    {
        shared->recList.removeAt(i);
    }

    shared->recMutex.unlock();

    return Loop::exec();
}

bool EventLoop::wrOutVod()
{
    auto cnt    = 0;
    auto concat = name + ".tmp";
    auto ret    = false;

    QFile file(concat);

    file.open(QFile::WriteOnly);

    for (auto &&vid : vidList)
    {
        recLog("event_src: " + vid, shared);

        if (QFile::exists(vid))
        {
            file.write(QString("file '" + vid + "'\n").toUtf8()); cnt++;
        }
    }

    file.close();

    if (cnt == 0)
    {
        recLog("err: none of the event hls clips exists, canceling write out.", shared);

        QFile::remove(concat);
    }
    else
    {
        QProcess    proc;
        QStringList args;

        args << "-f";
        args << "concat";
        args << "-safe" << "0";
        args << "-i" << concat;
        args << "-c" << "copy";
        args << "events/" + name + ".mp4";

        proc.setProgram("ffmpeg");
        proc.setArguments(args);
        proc.start();

        if (proc.waitForStarted())
        {
            recLog("concat_cmd_start: ok", shared);

            proc.waitForFinished(); ret = true;
        }
        else
        {
            recLog("concat_cmd_start: fail", shared);
            recLog("concat_cmd_stderr: " + QString(proc.readAllStandardError()), shared);
        }

        QFile::remove(concat);
    }

    return ret;
}

DetectLoop::DetectLoop(shared_t *sharedRes, QThread *thr, QObject *parent) : Loop(sharedRes, thr, parent)
{
    pcTimer     = 0;
    heartBeat   = 2;
    delayCycles = 12; // this will be used to delay the
                      // actual start of DetectLoop by
                      // 24secs.
}

void DetectLoop::init()
{
    pcTimer = new QTimer(this);
    mod     = false;

    connect(pcTimer, &QTimer::timeout, this, &DetectLoop::pcBreak);

    resetTimers();

    Loop::init();
}

void DetectLoop::resetTimers()
{
    pcTimer->start(shared->postSecs * 1000);
}

void DetectLoop::pcBreak()
{
    if (!shared->postCmd.isEmpty())
    {
        detLog("---POST_BREAK---", shared);

        if (mod)
        {
            detLog("motion detected, skipping the post command.", shared);
        }
        else
        {
            if (delayCycles == 0) delayCycles  = 5;
            else                  delayCycles += 5;

            detLog("no motion detected, running post command: " + shared->postCmd, shared);

            auto args = parseArgs(shared->postCmd.toUtf8(), -1);

            if (args.isEmpty())
            {
                detLog("err: did not parse an executable from the post command line.", shared);
            }
            else
            {
                QProcess::execute(args[0], args.mid(1));
            }
        }
    }

    mod = false;
}

float DetectLoop::getFloatFromExe(const QByteArray &line)
{
    QString strLine(line);
    QString strNum;

    for (auto chr : strLine)
    {
        if (chr.isDigit() || (chr == '.'))
        {
            strNum.append(chr);
        }
        else
        {
            break;
        }
    }

    return strNum.toFloat();
}

QStringList DetectLoop::buildArgs(const QString &prev, const QString &next)
{
    auto args = parseArgs(shared->compCmd.toUtf8(), -1);

    for (auto i = 0; i < args.size(); ++i)
    {
        if (args[i] == PREV_IMG) args[i] = prev;
        if (args[i] == NEXT_IMG) args[i] = next;
    }

    return args;
}

bool DetectLoop::exec()
{
    if (delayCycles > 0)
    {
        delayCycles -= 1;

        detLog("delay: detection cycle skipped. cycles left to be skipped: " + QString::number(delayCycles), shared);
    }
    else
    {
        auto curDT  = QDateTime::currentDateTime();
        auto images = backwardFacingFiles("img", ".bmp", curDT, 6);

        if (images.size() < 2)
        {
            detLog("wrn: didn't pick up enough image files from the image stream. number of files: " + QString::number(images.size()), shared);
            detLog("     will try again on the next loop.", shared);
        }
        else
        {
            auto pos  = images.size() - 1;
            auto args = buildArgs(images[pos - 1], images[pos]);

            if (args.isEmpty())
            {
                detLog("err: could not parse a executable name from img_comp_cmd: " + shared->compCmd, shared);
            }
            else
            {
                QProcess extComp;

                extComp.start(args[0], args.mid(1));
                extComp.waitForFinished();

                float score = 0;
                auto  ok    = true;

                if (shared->outputType == "stdout")
                {
                    score = getFloatFromExe(extComp.readAllStandardOutput());
                }
                else if (shared->outputType == "stderr")
                {
                    score = getFloatFromExe(extComp.readAllStandardError());
                }
                else
                {
                    ok = false;
                }

                if (!ok)
                {
                    detLog("err: img_comp_out: " + shared->outputType + " is not valid. it must be 'stdout' or 'stderr'" , shared);
                }
                else
                {
                    detLog(extComp.program() + " " + args.join(" ") +  " --result: " + QString::number(score), shared);

                    if (score >= shared->imgThresh)
                    {
                        detLog("--threshold_breached: " + QString::number(shared->imgThresh), shared);

                        evt_t event;

                        event.timeStamp = curDT;
                        event.score     = score;
                        event.imgPath   = images[pos];
                        event.queAge    = 0;

                        shared->recMutex.lock();
                        shared->recList.append(event); mod = true;
                        shared->recMutex.unlock();
                    }
                }
            }
        }
    }

    return Loop::exec();
}