app/sources/buzzerconn.cpp

/*
    Speed Climbing Stopwatch - Simple Stopwatch for Climbers
    Copyright (C) 2018  Itsblue Development - Dorian Zeder

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published
    by the Free Software Foundation, version 3 of the License.

    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 Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/

#include "headers/buzzerconn.h"

BuzzerConn::BuzzerConn(QObject *parent, QString ip, int port) : QObject(parent)
{
    this->socket = new QTcpSocket();

    this->date = new QDateTime;
    this->latest_button_pressed = 0;

    this->ip = ip;
    this->port = port;

    this->setState("disconnected");
    // "http://192.168.4.1"
}

bool BuzzerConn::connect()
{
    qDebug() << "connecting...";

    setState("connecting");

    //setup loop to wait until the connection has finished
    QEventLoop loop;
    QTimer timer;

    timer.setSingleShot(true);
    loop.connect(&timer, SIGNAL(timeout()), &loop, SLOT(quit()));
    loop.connect(this->socket, SIGNAL(connected()), &loop, SLOT(quit()));

    timer.start(3000);
    //connect
    this->socket->connectToHost(this->ip, this->port);

    //wait for the connection to finish
    loop.exec();

    //loop finished
    if(timer.remainingTime() == -1){
        //the time has been triggered -> timeout
        setState("disconnected");
        return(false);
    }
    timer.stop();


    QList<double> times = gettimes(2000, true);
    qDebug() << times;
    if(times[0] == 200.0){
        this->latest_button_pressed = times[2];
        for(int i=0;i<=100;i++){
            this->connection_progress = i;
            emit this->progressChanged();
            if(!calcoffset(this->gettimes(1000, false))){
                this->connection_progress = 100;
                setState("disconnected");
                return(false);
            }
        }
        setState("connected");
        return(true);
    }
    else{
        setState("disconnected");
        return(false);
    }
}

bool BuzzerConn::calcoffset(QList<double> times)
{
    if(times.length() != 2){
        return(false);
    }
    if(times[0] == 200.0){

        double offset = date->currentMSecsSinceEpoch() - times[1];
        if(this->latest_offsets.length()>=100){
            this->latest_offsets.removeFirst();
        }
        this->latest_offsets.append(offset);

        double mem = 0;
        for(int i=0;i<latest_offsets.length();i++){
            mem += latest_offsets[i];
        }
        this->offset = mem / double(latest_offsets.length());
        offsetChanged();
        //qDebug("%20f", this->offset);
        return(true);
    }
    else {
        //this->connected = false;
        return(false);
    }
}

QList<double> BuzzerConn::gettimes(int timeout, bool bothTimes)
{
    QList<double> times;
    signed long ret;
    ret = this->sendCommand("GET_TIMESTAMP", timeout);
    if(ret >= 0){

        times.append(double(200));
        times.append(double(ret));

        if(bothTimes){
            ret = this->sendCommand("GET_LASTPRESSED", timeout);

            if(ret >= 0){
                times.append(double(ret));
            }
            else {
                times[0] = ret;
            }
        }
    }
    else {
        times.append(ret);
    }
    return(times);

}

double BuzzerConn::get(QString key)
{
    if(key == "offset"){
        return(this->offset);
    }
    else if (key == "lastpressed") {
        return(this->latest_button_pressed);
    }
    else if( key == "currtime") {
        return(this->date->currentMSecsSinceEpoch());
    }
    else if( key == "connection_progress") {
        return(this->connection_progress);
    }
    else if( key == "connected") {
        if(this->state == "connected"){
            return(1);
        }
        return(0);
    }
    return(0);
}

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

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

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

void BuzzerConn::setState(QString newState){
    this->state = newState;
    emit stateChanged();
}

int BuzzerConn::getProgress() const
{
    return(connection_progress);
}

double BuzzerConn::getOffset() const
{
    return(this->offset);
}

double BuzzerConn::getLastTriggered() const
{
    return(this->latest_button_pressed);
}

bool BuzzerConn::refresh()
{
    if(this->state != "connected"){
        return(false);
    }

    //send one of the pending commands
    if(pending_commands.length() > 0){
        QString command = this->pending_commands.first();

        signed long retval = this->sendCommand(command, 2000);
        if(retval > 0){
            this->pending_commands.removeFirst();
        }
    }

    //refresh the times
    QList<double> ret = this->gettimes(2000);
    if(ret[0] >= 0){
        if(ret[2] > this->latest_button_pressed){
            this->latest_button_pressed = ret[2];
            emit triggered();
        }
        this->errors = 0;
        return(this->calcoffset(ret));
    }
    else {
        this->errors ++;
        if(this->errors > errors_until_disconnect){
            this->socket->disconnectFromHost();
            this->setState("disconnected");
        }
        return(false);
    }

}

signed long BuzzerConn::sendCommand(QString command, int timeout){

    //if there is any data in the storage, clear it
    if(this->socket->bytesAvailable() > 0){
        this->socket->readAll();
    }

    //send request to the socket server
    QByteArray arrBlock;
    QDataStream out(&arrBlock, QIODevice::WriteOnly);
    //out.setVersion(QDataStream::Qt_5_10);
    out << quint16(0) << command;

    out.device()->seek(0);
    out << quint16(arrBlock.size() - sizeof(quint16));

    this->socket->write(arrBlock);

    //now wait for the server of the sensor to answer
    QEventLoop loop;
    QTimer timer;

    timer.setSingleShot(true);
    loop.connect(&timer, SIGNAL(timeout()), &loop, SLOT(quit()));
    loop.connect(socket, SIGNAL(readyRead()), &loop, SLOT(quit()));
    timer.start(timeout);
    loop.exec();

    //loop finished
    if(timer.remainingTime() == -1){
        //the time has been triggered -> timeout
        return(-1);
    }

    timer.stop();


    //if the data is not 4 bytes long it is invalid -> clear and terminate
    if(this->socket->bytesAvailable() != 4){
        this->socket->readAll();
        return(-2);
    }
    long data = 0;
    this->socket->read((char*)&data,4);

    //qDebug() << data;
    //qDebug() << this->socket->bytesAvailable();

    return data;
}

void BuzzerConn::appendCommand(QString command){
    this->pending_commands.append(command);
}