/*
 * This file is part of Remote Support Desktop
 * https://gitlab.das-netzwerkteam.de/RemoteWebApp/rwa.support.desktopapp
 * Copyright 2020, 2021 Daniel Teichmann <daniel.teichmann@das-netzwerkteam.de>
 * Copyright 2020, 2021 Mike Gabriel <mike.gabriel@das-netzwerkteam.de>
 * SPDX-License-Identifier: GPL-2.0-or-later
 *
 * 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 2 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, write to the
 * Free Software Foundation, Inc.,
 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

#include "session.h"

Session::Session(DBusAPI *dbus_api, RWAHost *host) : QObject() {
    Q_ASSERT(host != nullptr);
    Q_ASSERT(dbus_api != nullptr);

    _dbus_api = dbus_api;
    _host = host;

    setPin("-----");
    setSessionID("-----");
    setURL(tr("Not available yet"));
    setStatus("unknown");
    started = false;
}

Session::~Session() {
    qDebug().noquote() << QString("Session #'%0' on host '%1' will be deconstructed.")
                          .arg(getSessionID())
                          .arg(getHost()->alias());
    stop();
    disconnect();
}

void Session::statusTimerEvent() {
    qDebug() << "Status timer event triggered";

    refresh_status();
}

bool Session::isSessionAliveOrRunning() {
    if (getStatus() == "running" || getStatus() == "active") {
        return true;
    } else {
        return false;
    }
}

RWAHost* Session::getHost() {
    return _host;
}

QString Session::getStatus() {
    return _status;
}

QString Session::getURL() {
    return _url;
}

QString Session::getSessionID() {
    return _session_id;
}

QString Session::getPin() {
    return _pin;
}

void Session::setURL(QString url) {
    _url = url;
    emit urlChanged(url);
}

void Session::setSessionID(QString session_id) {
    _session_id = session_id;
    emit sessionIDChanged(session_id);
}

void Session::setPin(QString pin) {
    _pin = pin;
    emit pinChanged(pin);
}

void Session::setHost(RWAHost *host) {
    _host = host;
    emit hostChanged(host);
}

void Session::setStatus(QString status) {
    _status = status;
    emit statusChanged(status);
}

void Session::start() {
    _dbus_api->start_request(_host);
}

void Session::start_response(QJsonDocument *doc) {
    // Q_ASSERT lets the program crash immediatly after method call
    // when the session service is not started.
    // Don't use Q_ASSERT(doc != nullptr); instead use:
    if (doc == nullptr) {
        emit startFailed(tr("Can't connect to underlying session service! "
                            "Is the session service started?"));
        return;
    }

    // Get the QJsonObject
    QJsonObject jObject = doc->object();
    QVariantMap mainMap = jObject.toVariantMap();

    // Status of request
    QString status = mainMap["status"].toString();
    if (status != "success") {
        QString type = mainMap["type"].toString();
        QString error_message = tr("An error occured while creating a new session!");

        if (type == "multiple") {
            // TODO: Ask to stop other session via a message dialog.
            error_message = tr("The session service is configured "
                               "to not support multiple sessions "
                               "and there is already a session running.");
        } else if (type == "connection") {
            error_message = tr("Couldn't connect to host '%0'.")
                                .arg(getHost()->alias());
        } else if (type == "host_not_found") {
            error_message = tr("The RWA host '%0' couldn't be found.")
                                .arg(getHost()->alias());
        } else if (type == "permission_denid") {
            error_message = tr("The RWA host '%0' doesn't grant access.")
                                .arg(getHost()->alias());
        } else if (type == "unsupported_server") {
            error_message = tr("The RWA host '%0' is not supported.")
                                .arg(getHost()->alias());
        }

        setStatus("start_session_error");
        qCritical().noquote() << error_message;
        emit startFailed(error_message);
        return;
    }

    bool ok;

    // URL of remote web app frontend
    QString url = mainMap["url"].toString();
    this->setURL(url);

    // PIN
    long long pin = mainMap["pin"].toLongLong(&ok);
    // Sanity Check
    if(ok == false){
        QString error_message = "Unable to parse <pin> into longo long out of dbus answer!";
        qCritical().noquote() << error_message;
        emit startFailed(error_message);
        return;
    }
    this->setPin(QString::number(pin));

    // session_id = remote support id from the rwa-server
    long long session_id = mainMap["session_id"].toLongLong();
    // Sanity Check
    if(ok == false){
        QString error_message = "Unable to parse <session_id> into long long out of dbus answer!";
        qCritical().noquote() << error_message;
        emit startFailed(error_message);
        return;
    }
    this->setSessionID(QString::number(session_id));

    qDebug() << "Got session_id:" << session_id <<
                "\nGot url:" << url <<
                "\nGot pin:" << pin;

    emit pinChanged(QString::number(pin));
    emit urlChanged(url);
    emit sessionIDChanged(QString::number(session_id));

    started = true;

    // Ask status every 1000 millisecond

    QTimer *timer = new QTimer(this);
    connect(timer, &QTimer::timeout, this,
            QOverload<>::of(&Session::statusTimerEvent));
    timer->start(1000);

    qDebug() << "Successfully started a session.";
    this->setStatus("start_session_success");

    emit startSucceeded();
}

void Session::stop() {
    if (started)
        _dbus_api->stop_request(getHost(), getSessionID());
}

void Session::stop_response(QJsonDocument *doc) {
    // Q_ASSERT lets the program crash immediatly after method call
    // when the session service is not started.
    // Don't use Q_ASSERT(doc != nullptr); instead use:
    if (doc == nullptr) {
        emit stopFailed(tr("Can't connect to underlying session service! "
                           "Is the session service started?"));
        return;
    }

    QJsonObject jObject = doc->object();
    QVariantMap mainMap = jObject.toVariantMap();

    QString new_status = mainMap["status"].toString();
    qDebug() << "stop_response() retrieved json. Status now:" << new_status;

    started = false;

    this->setStatus(new_status);

    emit stopSucceeded();
}

void Session::status() {
    _dbus_api->status_request(getHost(), this->getSessionID());
}

void Session::refresh_status() {
    _dbus_api->refresh_status_request(getHost(), this->getSessionID());
}

void Session::status_response(QJsonDocument *doc) {
    // Q_ASSERT lets the program crash immediatly after method call,
    // when the session service is not started.
    // Don't use Q_ASSERT(doc != nullptr); instead use:
    if (doc == nullptr) {
        if (!_emitted_status_error_already) {
            emit statusFailed(tr("Can't connect to underlying session service! "
                                 "Is the session service started?"));

            _emitted_status_error_already = true;
        }

        return;
    }

    _emitted_status_error_already = false;

    QJsonObject jObject = doc->object();
    QVariantMap mainMap = jObject.toVariantMap();
    QString new_status = mainMap["status"].toString();
    qDebug() << "status_response() retrieved json. Status:" << new_status;

    setStatus(new_status);

    emit statusSucceeded();
}