/****************************************************************************
 ** ScStw Libraries
 ** Copyright (C) 2020  Itsblue development
 **
 ** This program 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.
 **
 ** This program 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.
 **
 ** You should have received a copy of the GNU General Public License
 ** along with this program.  If not, see <http://www.gnu.org/licenses/>.
 ****************************************************************************/

#include "../headers/scstwrace.h"

ScStwRace::ScStwRace(QObject *parent) : QObject(parent)
{
    this->state = IDLE;

    // configure the loop that waits for the sound effect to finish
    this->soundPlayer = new ScStwSoundPlayer();

    // configure timer that handles the delay between the start commands
    this->startDelayTimer = new QTimer(this);
    startDelayTimer->setSingleShot(true);
    this->startWaitLoop = new QEventLoop(this);

    connect(this->startDelayTimer, &QTimer::timeout, this->startWaitLoop, &QEventLoop::quit);

    // write default settings
    this->startSoundSettings.insert(ScStwSoundPlayer::Start, {{"Enabled", true}, {"Delay", 1}});
    this->writeStartSoundSetting(ScStwSoundPlayer::AtYourMarks, false, 0);
    this->writeStartSoundSetting(ScStwSoundPlayer::Ready, false, 0);
    this->setSoundVolume(1.0);
    this->competitionMode = false;
}

// --------------------------
// --- Main Functionality ---
// --------------------------

int ScStwRace::start(bool asyncronous) {
    if(this->state == WAITING) {
        if(this->isReadyForNextState()) {
            this->startWaitLoop->exit(LoopManualExit);
            return ScStw::Success;
        }
        else {
            return ScStw::TimersNotReadyError;
        }
    }
    else if(this->state !=  IDLE) {
        return ScStw::CurrentStateNotVaildForOperationError;
    }

    qDebug() << "[INFO][RACE] checking timers";
    if(!this->isReadyForNextState())
        return ScStw::TimersNotReadyError;

    qDebug() << "[INFO][RACE] starting race";
    this->setState(PREPAIRING);

    if(asyncronous) {
        QTimer::singleShot(1, [=](){this->playSoundsAndStartTimers();});
    }
    else
        this->playSoundsAndStartTimers();

    return ScStw::Success;
}

int ScStwRace::stop() {
    if(this->state != RUNNING && this->state !=  STARTING) {
        return ScStw::CurrentStateNotVaildForOperationError;
    }

    qDebug() << "+ [INFO] stopping race";

    double timeOfStop = QDateTime::currentMSecsSinceEpoch();

    int returnCode = ScStw::Success;

    foreach(ScStwTimer *speedTimer, this->timers){
        if(!speedTimer->stop(timeOfStop) && speedTimer->getState() != ScStwTimer::DISABLED){
            returnCode = ScStw::InternalErrorTimerOperationFailed;
        }
    }

    if(returnCode == ScStw::Success) {
        this->setState(STOPPED);
    }

    return returnCode;
}

void ScStwRace::handleTimerStop() {
    if(this->state == RUNNING) {
        // find out which timer has won
        double lowestStoppedTime = -1;
        QList<ScStwTimer *> timersWhichHaveWonIds;

        // iterate through all timers and find the lowest time taht was stopped
        foreach(ScStwTimer * timer, this->timers) {
            if(timer->getCurrentTime() > 0 && (timer->getCurrentTime() <= lowestStoppedTime || lowestStoppedTime < 0)) {
                // this is the timer with the lowest stopped time
                lowestStoppedTime = timer->getCurrentTime();
            }
        }

        // append the timer(s) with the lowest stopped time to the winner list
        foreach(ScStwTimer * timer, this->timers) {
            if(timer->getCurrentTime() > 0
                    && (timer->getCurrentTime() <= lowestStoppedTime || lowestStoppedTime < 0)
                    && timer->getState() != ScStwTimer::RUNNING
                    ) {
                // this is the timer with the lowest stopped time
                timersWhichHaveWonIds.append(timer);
            }
        }

        // update the states of all timers
        foreach(ScStwTimer * timer, this->timers) {
            if(timer->getState() == ScStwTimer::RUNNING)
                continue;

            if(timersWhichHaveWonIds.contains(timer)) {
                timer->setResult(ScStwTimer::WON);
            }
            else {
                timer->setResult(ScStwTimer::LOST);
            }
        }
    }
}

int ScStwRace::reset() {
    if(this->state != STOPPED && this->state != INCIDENT) {
        return ScStw::CurrentStateNotVaildForOperationError;
    }

    qDebug() << "+ [INFO] resetting race";

    int returnCode = ScStw::Success;

    foreach(ScStwTimer *speedTimer, this->timers){
        if(!speedTimer->reset() && speedTimer->getState() != ScStwTimer::DISABLED) {
            returnCode = ScStw::InternalErrorTimerOperationFailed;
        }
    }

    if(returnCode == ScStw::Success)
        this->setState(IDLE);

    return returnCode;
}

int ScStwRace::cancel() {
    if(this->state != PREPAIRING && this->state != WAITING && this->state != STARTING && this->state != RUNNING)
        return ScStw::CurrentStateNotVaildForOperationError;

    qDebug() << "[INFO][RACE] cancelling race";

    int returnCode = ScStw::Success;

    foreach(ScStwTimer *timer, this->timers){
        if(!timer->cancel() && timer->getState() != ScStwTimer::DISABLED)
            returnCode = ScStw::InternalErrorTimerOperationFailed;
    }

    if(returnCode != ScStw::Success)
        return returnCode;

    this->setState(STOPPED);

    this->startWaitLoop->exit(LoopCancelExit);
    this->soundPlayer->cancel(this->soundVolume);
    this->startDelayTimer->stop();

    return returnCode;
}

int ScStwRace::handleFalseStart() {
    if(this->getState() != STARTING && this->getState() != RUNNING)
        return ScStw::CurrentStateNotVaildForOperationError;

    int returnCode = ScStw::Success;
    // cancel all running timers
    foreach(ScStwTimer *timer, this->timers) {
        if(!timer->cancel() && timer->getState() != ScStwTimer::DISABLED && timer->getState() != ScStwTimer::FAILED)
            returnCode = ScStw::InternalErrorTimerOperationFailed;
    }

    this->setState(STOPPED);
    this->soundPlayer->cancel(this->soundVolume);

    return returnCode;
}

bool ScStwRace::playSoundsAndStartTimers() {
    if(this->state != PREPAIRING)
        return true;

    // The check if all timers are ready has already happened at this point
    qDebug() << "now playing at marks sound";
    if(!this->doDelayAndSoundOfCurrentStartState())
        return false;

    // check if the start was cancelled
    if(!this->isStarting())
        return false;

    qDebug() << "Now in waiting state";
    this->setState(WAITING);

    // do climber readiness tests

    // wait until both climbers are ready

    // if the automatic ready tone is enabled, wait for the climbers to become ready
    if(this->competitionMode && this->startSoundSettings.contains(ScStwSoundPlayer::Ready) && this->startSoundSettings[ScStwSoundPlayer::Ready]["Enabled"].toBool()) {

        qDebug() << "[RACE][INFO] Now waiting for climbers";

        // get delay
        int minimumReadyDelay = 1000;
        if(this->startSoundSettings[ScStwSoundPlayer::Ready]["Delay"].toInt() > 1000)
            minimumReadyDelay = this->startSoundSettings[ScStwSoundPlayer::Ready]["Delay"].toInt();

        this->startDelayTimer->setInterval(minimumReadyDelay);

        // wait for climbers to become ready initially
        bool timerTriggered = true;
        do {

            if(!this->isReadyForNextState()) {
                this->startDelayTimer->stop();
                timerTriggered = false;
            }
            else if(this->startDelayTimer->isActive()) {
                timerTriggered = true;
            }
            else {
                this->startDelayTimer->stop();
                this->startDelayTimer->start();
                timerTriggered = true;
            }

            emit this->currentStartDelayChanged();


            qDebug() << "entering wait loop...";
            int loopExitCode = this->startWaitLoop->exec();
            qDebug() << "wait loop exited with code " << loopExitCode;

            switch (loopExitCode) {
            case LoopAutomaticExit:
                break;
            case LoopManualExit:
                // prevent manual stop
                timerTriggered = false;
                break;
            case LoopCancelExit:
                return false;
            }

            qDebug() << "At end of loop: remaining time: " << this->startDelayTimer->remainingTime() << " timer triggered: " << timerTriggered << " ready for next state: " << this->isReadyForNextState();

        } while(this->startDelayTimer->remainingTime() > 0 || !timerTriggered  || !this->isReadyForNextState());

        qDebug() << "[RACE][DEBUG] Initial wait finished";

        // wait for all climbers to be ready for the ReadyActionDelay, but at least one second continuosly
        // the climber ready wait loop will also quit, if the climber steps of the pad
        // -> wait for both climbers to stand on the pad for at least one second

        qDebug() << "[RACE][DEBUG] Wait finished, starting now!";

        // play ready tone
        if(!this->soundPlayer->play(ScStwSoundPlayer::Ready, this->soundVolume))
            return false;
    }
    else if(this->competitionMode) {
        // wait for climbers and manual start
        int loopExitCode;
        do {
            loopExitCode = this->startWaitLoop->exec();

            if(loopExitCode == LoopCancelExit)
                return false;

        } while(loopExitCode != LoopManualExit || !this->isReadyForNextState());
    }
    else {
        qDebug() << "now playing ready sound";
        if(!this->doDelayAndSoundOfCurrentStartState())
            return false;
    }

    qDebug() << "now in starting state";

    // enter starting state
    this->setState(STARTING);

    // play start tone
    qDebug() << "now playing start sound";
    double timeOfSoundPlaybackStart;
    this->doDelayAndSoundOfCurrentStartState(&timeOfSoundPlaybackStart);

    // perform start

    // start all timers
    bool startOk = true;
    foreach(ScStwTimer *timer, this->timers){
        if(!timer->start(timeOfSoundPlaybackStart + 3100) && timer->getState() != ScStwTimer::DISABLED){
            startOk = false;
        }
    }
    if(!startOk) {
        qDebug() << "[ERROR][START] error staring all timers";
        return false;
    }

    if(!this->soundPlayer->waitForSoundFinish()) {
        qDebug() << "[ERROR][START] start sound wait error";
        return false;
    }

    // check if a false start occured
    if(!this->isStarting())
        return true;

    this->setState(RUNNING);

    return true;


}

bool ScStwRace::doDelayAndSoundOfCurrentStartState(double *timeOfSoundPlaybackStart) {
    ScStwSoundPlayer::StartSound sound;

    switch (this->state) {
    case PREPAIRING:
        sound = ScStwSoundPlayer::AtYourMarks;
        break;
    case WAITING:
        sound = ScStwSoundPlayer::Ready;
        break;
    case STARTING:
        sound = ScStwSoundPlayer::Start;
        break;
    default:
        return false;
    }

    if(this->startSoundSettings.contains(sound) && this->startSoundSettings[sound]["Enabled"].toBool()) {
        if(sound != ScStwSoundPlayer::Start && this->startSoundSettings[sound]["Delay"].toInt() > 0) {
            // perform the delay before the start

            // get delay
            int thisSoundDelay = this->startSoundSettings[sound]["Delay"].toInt();

            // perform next action
            if(thisSoundDelay > 0) {
                this->startDelayTimer->setInterval(thisSoundDelay);
                this->startDelayTimer->start();

                emit this->currentStartDelayChanged();

                if(this->startWaitLoop->exec() == LoopCancelExit)
                    return false;
            }
        }

        if(!this->isStarting())
            return false;

        if(!this->soundPlayer->play(sound, this->soundVolume, timeOfSoundPlaybackStart))
            return false;
    }

    return true;
}

void ScStwRace::setState(RaceState newState) {
    if(newState != this->state) {
        qDebug() << "[INFO][RACE] state changed: " << newState;
        this->state = newState;
        emit this->stateChanged(newState);

        if(this->state == IDLE) {
            // if we changed to IDLE -> handle timer enable / disable
            if(this->competitionModeChanged && this->competitionMode) {
                this->enableAllTimers();
                this->competitionModeChanged = false;
            }

            if(!this->competitionMode) {
                foreach(ScStwTimer* timer, this->timers) {
                    if(timer->getWantsToBeDisabled() && timer->getState() != ScStwTimer::DISABLED)
                        this->handleTimerWantsToBeDisabledChange(timer, timer->getWantsToBeDisabled());
                }
            }
        }
    }
}

void ScStwRace::refreshTimerStates() {

    qDebug() << "[INFO][MAIN] refreshing timer states";

    // check if the race is over
    bool raceIsOver = true;

    foreach(ScStwTimer * timer, this->timers){
        if(timer->getState() < ScStwTimer::WON && timer->getState() != ScStwTimer::WAITING){
            // if the timer is not in stoped state
            raceIsOver = false;
            break;
        }
        else if(timer->getState() == ScStwTimer::WAITING) {
            this->handleTimerStop();
        }
        else if (timer->getState() == ScStwTimer::FAILED) {
            this->handleFalseStart();
        }
    }

    if(raceIsOver)
        this->setState(STOPPED);
}

// ------------------------
// --- helper functions ---
// ------------------------

bool ScStwRace::isReadyForNextState() {
    if(!this->competitionMode) {
        return true;
    }

    switch (this->state) {
    case IDLE: {
        foreach (ScStwTimer *timer, this->timers) {
            if(timer->getState() == ScStwTimer::DISABLED)
                continue;

            if(timer->getReadyState() == ScStwTimer::ExtensionIsNotConnected || timer->getReadyState() == ScStwTimer::ExtensionBatteryNotFine) {

                qDebug() << "Timer ready state is: " << timer->getReadyState();

                timer->technicalIncident();

                foreach (ScStwTimer *subTimer, this->timers) {
                    if(timer != subTimer && (timer->getReadyState() == ScStwTimer::ExtensionIsNotConnected || timer->getReadyState() == ScStwTimer::ExtensionBatteryNotFine))
                        subTimer->technicalIncident();
                    else if(timer != subTimer)
                        subTimer->setState(ScStwTimer::CANCELLED);
                }

                this->setState(INCIDENT);

                qDebug() << "[ERROR][RACE] Could not start due to not-ready timers";

                return false;
            }
        }

        break;
    case WAITING: {
            foreach (ScStwTimer *timer, this->timers) {
                if(timer->getReadyState() != ScStwTimer::IsReady)
                    return false;
            }
            break;
        }

        default:
            break;;
        }

    }

    return true;

}

/**
 * @brief ScStwRace::handleTimerEnable function to enable timers at the right moment to prevent them from bricking the state machine
 * @param {ScStwExtensionControlledTimer*} timer timer to be enabled
 */
void ScStwRace::handleTimerWantsToBeDisabledChange(ScStwTimer* timer, bool wantsToBeDisabled) {
    if(this->competitionMode)
        return;

    if(this->state == IDLE) {
        timer->setDisabled(wantsToBeDisabled);
    }
}

void ScStwRace::setCompetitionMode(bool competitionMode) {
    if(this->competitionMode == competitionMode)
        return;

    qDebug() << "Setting competition mode to " << competitionMode;

    this->competitionMode = competitionMode;

    if(this->state != IDLE)
        this->competitionModeChanged = true;
    else if(this->competitionMode)
        this->enableAllTimers();
}

void ScStwRace::enableAllTimers() {
    if(this->state != IDLE)
        return;

    qDebug() << "ENABLING ALL TIMERS";

    foreach (ScStwTimer *timer, this->timers) {
        timer->setDisabled(false);
    }
}

QVariantList ScStwRace::getCurrentStartDelay() {
    int nextActionDelay = 0;
    double nextActionDelayProg = -1;

    if(this->state == PREPAIRING || this->state == WAITING) {
        // get the total delay and the delay progress of the next action timer
        double remaining = this->startDelayTimer->remainingTime();
        nextActionDelay = this->startDelayTimer->interval();;
        if(remaining < 0) {
            remaining = nextActionDelay;
        }
        nextActionDelayProg = 1 - (remaining / nextActionDelay);
    }

    return {
                nextActionDelay,
                nextActionDelayProg
    };
}

bool ScStwRace::writeStartSoundSetting(ScStwSoundPlayer::StartSound sound, bool enabled, int delay) {
    if(sound != ScStwSoundPlayer::AtYourMarks && sound != ScStwSoundPlayer::Ready)
        return false;

    QVariantMap setting = {{"Enabled", enabled}, {"Delay", delay}};

    if(!this->startSoundSettings.contains(sound))
        this->startSoundSettings.insert(sound, setting);
    else
        this->startSoundSettings[sound] = setting;

    return true;
}

bool ScStwRace::setSoundVolume(double volume) {
    if(volume >= 0 && volume <= 1) {
        this->soundVolume = volume;
        return true;
    }
    else {
        return false;
    }
}

bool ScStwRace::addTimer(ScStwTimer *timer) {
    if(this->state != IDLE)
        return false;

    foreach(ScStwTimer *existingTimer, this->timers) {
        if(existingTimer == timer)
            return true;
    }

    this->timers.append(timer);

    connect(timer, &ScStwTimer::stateChanged, this, &ScStwRace::refreshTimerStates);
    connect(timer, &ScStwTimer::wantsToBeDisabledChanged, this, &ScStwRace::handleTimerWantsToBeDisabledChange);
    connect(timer, &ScStwTimer::stateChanged, this, &ScStwRace::timersChanged);
    connect(timer, &ScStwTimer::reactionTimeChanged, this, &ScStwRace::timersChanged);
    connect(timer, &ScStwTimer::readyStateChanged, this->startWaitLoop, &QEventLoop::quit);

    if(this->competitionMode && timer->getState() == ScStwTimer::DISABLED)
        timer->setDisabled(false);

    return true;

}

ScStwRace::RaceState ScStwRace::getState() {
    return this->state;
}

QList<ScStwTimer*> ScStwRace::getTimers() {
    return this->timers;
}

QVariantList ScStwRace::getTimerDetailList() {
    QVariantList tmpTimers;

    foreach(ScStwTimer * timer, this->timers){
        QVariantMap tmpTimer;
        tmpTimer.insert("id", this->timers.indexOf(timer));
        tmpTimer.insert("state", timer->getState());
        tmpTimer.insert("currentTime", timer->getCurrentTime());
        tmpTimer.insert("reactionTime", timer->getReactionTime());
        tmpTimer.insert("text", timer->getText());
        tmpTimer.insert("letter", timer->getLetter());
        tmpTimers.append(tmpTimer);
    }

    return tmpTimers;
}

bool ScStwRace::isStarting() {
    return this->state == PREPAIRING || this->state == WAITING || this->state == STARTING;
}