#include "baseconn.h"

BaseConn::BaseConn(QObject *parent) : QObject(parent)
{
    socket = new QTcpSocket(this);

    this->timeoutTimer = new QTimer(this);
    this->timeoutTimer->setSingleShot(true);

    this->state = "disconnected";

    connect(this->socket, SIGNAL(error(QAbstractSocket::SocketError)),
            this, SLOT(gotError(QAbstractSocket::SocketError)));

    connect(this->socket, &QAbstractSocket::stateChanged, this, &BaseConn::socketStateChanged);
    connect(this, &BaseConn::gotUpdate, this, &BaseConn::handleUpdate);

    this->nextConnectionId = 1;

    // init refresh timers
    this->autoConnectRetryTimer = new QTimer(this);
    this->autoConnectRetryTimer->setInterval(1000);
    this->autoConnectRetryTimer->setSingleShot(true);
    connect(this->autoConnectRetryTimer, &QTimer::timeout, this, &BaseConn::doConnectionAttempt);
    this->autoConnectRetryTimer->start();

    this->timerTextRefreshTimer = new QTimer(this);
    this->timerTextRefreshTimer->setInterval(1);
    this->timerTextRefreshTimer->setSingleShot(true);
    connect(this->timerTextRefreshTimer, &QTimer::timeout, this, &BaseConn::refreshTimerTextList);
    this->timerTextRefreshTimer->start();
}

void BaseConn::connectToHost() {
    qDebug() << "+--- connecting";
    setState("connecting");

    connect(this->timeoutTimer, SIGNAL(timeout()), this, SLOT(connectionTimeout()));

    //connect
    this->socket->connectToHost(this->ip, this->port);

    timeoutTimer->start(3000);
}

void BaseConn::connectionTimeout() {
    this->socket->abort();
    disconnect(this->timeoutTimer, SIGNAL(timeout()), this, SLOT(connectionTimeout()));
}

bool BaseConn::init() {
    disconnect(this->timeoutTimer, SIGNAL(timeout()), this, SLOT(connectionTimeout()));
    this->timeoutTimer->stop();

    connect(this->socket, &QTcpSocket::readyRead, this, &BaseConn::readyRead);

    this->setState("connected");

    // init remote session
    QJsonArray updateSubs = {"onTimersChanged", "onRaceStateChanged", "onNextStartActionChanged"};
    QJsonObject sessionParams = {{"updateSubs", updateSubs}, {"init", true}};

    if(this->sendCommand(1, sessionParams)["status"] != 200) {
        return false;
    }

    return true;
}

void BaseConn::deInit() {
}

void BaseConn::closeConnection()
{
    qDebug() << "+--- closing connection";
    switch (socket->state())
    {
    case 0:
        socket->disconnectFromHost();
        break;
    case 2:
        socket->abort();
        break;
    default:
        socket->abort();
    }

    setState("disconnected");
}

void BaseConn::gotError(QAbstractSocket::SocketError err)
{
    //qDebug() << "got error";
    QString strError = "unknown";
    switch (err)
    {
    case 0:
        strError = "Connection was refused";
        break;
    case 1:
        strError = "Remote host closed the connection";
        this->closeConnection();
        break;
    case 2:
        strError = "Host address was not found";
        break;
    case 5:
        strError = "Connection timed out";
        break;
    default:
        strError = "Unknown error";
    }

    emit gotError(strError);
}

// -------------------------------------
// --- socket communication handling ---
// -------------------------------------

void BaseConn::socketStateChanged(QAbstractSocket::SocketState socketState) {
    switch (socketState) {
    case QAbstractSocket::UnconnectedState:
    {
        this->setState("disconnected");
        break;
    }
    case QAbstractSocket::ConnectedState:
    {
        if(this->init()) {
            this->setState("connected");
        }
        else {
            this->closeConnection();
        }

        break;
    }
    default:
    {
        //qDebug() << "+ --- UNKNOWN SOCKET STATE: " << socketState;
        break;
    }
    }
}

QVariantMap BaseConn::sendCommand(int header, QJsonValue data){
    if(this->state != "connected"){
        return {{"status", 910}, {"data", "not connected"}};
    }

    // generate id and witing requests entry
    int thisId = nextConnectionId;
    //qDebug() << "sending command: " << header << " with data: " << data << " and id: " << thisId;
    nextConnectionId ++;

    QEventLoop *loop = new QEventLoop(this);
    QTimer *timer = new QTimer(this);
    QJsonObject reply;

    this->waitingRequests.append({thisId, loop, reply});

    QJsonObject requestObj;
    requestObj.insert("id", thisId);
    requestObj.insert("header", header);
    requestObj.insert("data", data);

    QString jsonRequest = QJsonDocument(requestObj).toJson();

    timer->setSingleShot(true);
    // quit the loop when the timer times out
    loop->connect(timer, SIGNAL(timeout()), loop, SLOT(quit()));
    // quit the loop when the connection was established
    // loop.connect(this, &BaseConn::gotReply, &loop, &QEventLoop::quit);
    // start the timer before starting to connect
    timer->start(3000);

    //write data
    socket->write(jsonRequest.toLatin1());

    //wait for an answer to finish (programm gets stuck in here)
    loop->exec();

    bool replyFound = false;

    // find reply and delete the request from waiting list
    for(int i = 0; i<this->waitingRequests.length(); i++){
        if(this->waitingRequests[i].id == thisId){
            // request was found
            replyFound = true;
            // delete event loop
            if(this->waitingRequests[i].loop != nullptr) {
                delete this->waitingRequests[i].loop;
            }
            // store reply
            reply = this->waitingRequests[i].reply;
            // remove reply from waiting list
            this->waitingRequests.removeAt(i);
        }
    }

    if(!replyFound) {
        // some internal error occured
        return {{"status", 900}, {"data", ""}};
    }

    if(timer->remainingTime() == -1){
        //the time has been triggered -> timeout
        return {{"status", 911}, {"data", ""}};
    }

    delete timer;

    return {{"status", reply.value("header").toInt()}, {"data", reply.value("data").toVariant()}};

}

void BaseConn::readyRead() {

    //qDebug() << "ready to ready " << socket->bytesAvailable() << " bytes" ;
    QString reply = socket->readAll();

    //qWarning() << "socket read: " << reply;

    processSocketMessage(reply);
}

void BaseConn::processSocketMessage(QString message){
    QString startKey = "<message>";
    QString endKey = "</message>";

    //qWarning() << "... processing message now ... : " << message;

    if(message == ""){
        return;
    }

    if((message.startsWith(startKey) && message.endsWith(endKey)) && (message.count(startKey) == 1 && message.count(endKey) == 1)){
        // non-split message ( e.g.: <message>123456789</message>
    }
    else if(!message.contains(endKey) && (!this->readBuffer.isEmpty() || message.startsWith(startKey))){
        // begin of a split message ( e.g.: <message>123 )
        // or middle of a split message ( e.g.: 456 )
        //qWarning() << "this is a begin or middle of split a message";
        this->readBuffer += message;
        return;
    }
    else if(!message.contains(startKey) && message.endsWith(endKey)) {
        // end of a split message ( e.g.: 789</message> )

        if(!this->readBuffer.isEmpty()){
            message = readBuffer + message;
            readBuffer.clear();
        }
    }
    else if((message.count(startKey) > 1 || message.count(endKey) > 1) || (message.contains(endKey) && !message.endsWith(endKey) && message.contains(startKey) && !message.startsWith(startKey))) {
        // multiple messages in one packet ( e.g.: <message>123456789</message><message>987654321</message> )
        // or multiple message fragments in one message ( e.g.: 56789</message><message>987654321</message> or 56789</message><message>98765 )
        //qDebug() << "detected multiple messages";

        int startOfSecondMessage = message.lastIndexOf(startKey);
        // process first part of message
        QString firstMessage = message.left(startOfSecondMessage);
        this->processSocketMessage(firstMessage);
        // process second part of message
        QString secondMessage = message.right(message.length() - startOfSecondMessage);
        this->processSocketMessage(secondMessage);

        return;
    }
    else {
        // invalid message
        return;
    }

    //qWarning() << "... done processing, message: " << message;
    this->socketReplyRecieved(message);
}

void BaseConn::socketReplyRecieved(QString reply) {
    reply.replace("<message>", "");
    reply.replace("</message>", "");

    int id = 0;

    QJsonDocument jsonReply = QJsonDocument::fromJson(reply.toUtf8());
    QJsonObject replyObj = jsonReply.object();

    //qDebug() << "got: " << reply;

    if(!replyObj.isEmpty()){
        id = replyObj.value("id").toInt();

        if(id == -1) {
            // this message is an update!!
            emit this->gotUpdate(replyObj.toVariantMap());
            return;
        }

        for(int i = 0; i < this->waitingRequests.length(); i++){
            if(this->waitingRequests[i].id == id){
                this->waitingRequests[i].reply = replyObj;
                if(this->waitingRequests[i].loop != nullptr){
                    this->waitingRequests[i].loop->quit();
                }
                return;
            }
        }
    }

    latestReadReply = reply;
    emit gotUnexpectedReply(reply);
}

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

void BaseConn::doConnectionAttempt()
{
    if(this->state ==  "disconnected") {
        qDebug() << "+--- trying to connect";
        this->connectToHost();
    }

    this->autoConnectRetryTimer->start();
}

void BaseConn::setState(QString newState){
    if(this->state != newState) {
        qDebug() << "+--- BaseConn state changed: " << newState;
        this->state = newState;
        emit stateChanged();
        if(this->state == "disconnected") {
            this->deInit();
        }
    }
}

int BaseConn::writeRemoteSetting(QString key, QString value) {
    QJsonArray requestData;
    requestData.append(key);
    requestData.append(value);
    return this->sendCommand(3000, requestData)["status"].toInt();
}

QString BaseConn::readRemoteSetting(QString key)
{
    QVariantMap reply = this->sendCommand(3001, key);
    if(reply["status"] != 200){
        return "false";
    }
    return reply["data"].toString();
}

// ------------------
// - for timer sync -
// ------------------

void BaseConn::handleUpdate(QVariantMap data) {
    int header = data["header"].toInt();
    switch (header) {
    case 9000:
    {
        // the remote race state changed
        this->remoteRaceState = data["data"].toInt();
        this->raceStateChanged();
        break;
    }
    case 9001:
    {
        // the remote timers have changed
        this->refreshRemoteTimers(data["data"].toList());
        break;
    }
    case 9003:
    {
        // the next start action has changed
        this->nextStartActionTotalDelay = data["data"].toMap()["nextActionDelay"].toDouble();
        this->nextStartActionDelayStartedAt = this->date->currentMSecsSinceEpoch() - (this->nextStartActionTotalDelay * data["data"].toMap()["nextActionDelayProg"].toDouble());
        this->nextStartAction =  NextStartAction( data["data"].toMap()["nextAction"].toInt() );

        emit this->nextStartActionChanged();
    }

    }
}

void BaseConn::refreshRemoteTimers(QVariantList timers) {
    QVariantList remoteTimers;

    for (int i = 0; i < timers.length(); i++) {
        QVariantMap thisTimer = timers[i].toMap();
        if(thisTimer["state"].toInt() != DISABLED ) {
            thisTimer.insert("startTime", this->date->currentMSecsSinceEpoch() - thisTimer["currTime"].toDouble());
            remoteTimers.append(thisTimer);
        }
    }

    this->remoteTimers = remoteTimers;
}

void BaseConn::refreshTimerTextList() {
    QVariantList tmpTimerTextList;

    for (int i = 0; i < this->remoteTimers.toList().length(); i++) {

        QString newText;

        switch (this->remoteTimers.toList()[i].toMap()["state"].toInt()) {
        case IDLE:
            newText = "00.000";
            break;
        case STARTING:
            newText = "00.000";
            break;
        case WAITING:
            newText = "False Start";
            break;
        case RUNNING: {
            double currTime = this->date->currentMSecsSinceEpoch() - this->remoteTimers.toList()[i].toMap()["startTime"].toDouble();
            QString currTimeString = (currTime < 10000 ? "0":"") + QString::number( currTime / 1000.0, 'f', 3 );//QString::number( (currTime) / 1000.0, 'f', 1 );
            newText = currTimeString;
            break;
        }
        case WON: {
            double currTime = this->remoteTimers.toList()[i].toMap()["currTime"].toDouble();
            newText = (currTime < 10000 ? "0":"") + QString::number( currTime / 1000.0, 'f', 3 );
            break;
        }
        case LOST: {
            double currTime = this->remoteTimers.toList()[i].toMap()["currTime"].toDouble();
            newText = (currTime < 10000 ? "0":"") + QString::number( currTime / 1000.0, 'f', 3 );
            break;
        }
        case FAILED:
            newText = "False Start";
            break;
        case CANCELLED:
            newText = "Cancelled";
            break;
        case DISABLED:
            newText = "---";
            break;
        }

        QVariantMap timerMap = {{"text", newText}, {"reactTime", this->remoteTimers.toList()[i].toMap()["reactTime"].toInt()}, {"state", this->remoteTimers.toList()[i].toMap()["state"].toInt()}};
        tmpTimerTextList.append(timerMap);
    }

    if(tmpTimerTextList != this->timerTextList) {
        this->timerTextList = tmpTimerTextList;
        emit this->timerTextChanged();
    }

    // calculate next start action delay progress
    double nextStartActionRemainingDelay = this->nextStartActionTotalDelay - ( this->date->currentMSecsSinceEpoch() - this->nextStartActionDelayStartedAt );
    if(nextStartActionRemainingDelay > 0){
        this->nextStartActionDelayProgress = nextStartActionRemainingDelay / this->nextStartActionTotalDelay;
        emit this->nextStartActionDelayProgressChanged();
    }
    else {
        this->nextStartActionDelayProgress = 0;
        emit this->nextStartActionDelayProgressChanged();
    }

    this->timerTextRefreshTimer->start();
}

// -----------
// - for qml -
// -----------

void BaseConn::setIP(const QString &ipAdress){
    this->ip = ipAdress;
}

QString BaseConn::getIP() const
{
    return(this->ip);
}

QString BaseConn::getState() const
{
    return(this->state);
}

QVariant BaseConn::getTimerTextList()
{
    return this->timerTextList;
}

int BaseConn::getRaceState()
{
    return this->remoteRaceState;
}

double BaseConn::getNextStartActionDelayProgress() {
    return this->nextStartActionDelayProgress;
}

int BaseConn::getNextStartAction() {
    return this->nextStartAction;
}