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#include "settingsmanager.h"

#include <QDebug>
#include <QDir>
#include <QFile>
#include <QTemporaryFile>

#include <sys/reboot.h>
#include <unistd.h>

const QString QdbdFileName(QStringLiteral("/etc/default/qdbd"));
const char *ProtocolSetting("USB_ETHERNET_PROTOCOL=");

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

bool SettingsManager::hasQdb()
{
    return QFile::exists(QdbdFileName);
}

QString SettingsManager::usbMode()
{
    static bool initialized = false;
    if (!initialized) {
        QFile file(QdbdFileName);
        if (file.open(QIODevice::ReadOnly | QIODevice::Text)) {
            QByteArray line;
            while (!(line = file.readLine()).isEmpty()) {
                if (line.startsWith(ProtocolSetting))
                    m_usbMode =
                            QString::fromLatin1(line.last(line.length() - strlen(ProtocolSetting)))
                                    .trimmed();
            }
        } else {
            qWarning() << "Failed to open file" << QdbdFileName;
        }
        initialized = true;
    }
    return m_usbMode;
}

void SettingsManager::setUsbMode(const QString &usbMode)
{
    QFile file(QdbdFileName);
    QTemporaryFile newFile(QdbdFileName);
    newFile.setAutoRemove(false);
    if (!newFile.open()) {
        qWarning() << "Failed to save qdbd settings:" << newFile.errorString();
        return;
    }

    if (file.open(QIODevice::ReadOnly | QIODevice::Text)) {
        QTextStream out(&newFile);
        QByteArray line;
        while (!(line = file.readLine()).isEmpty()) {
            if (line.startsWith(ProtocolSetting))
                out << ProtocolSetting << usbMode.toLatin1() << '\n';
            else
                out << line;
        }

        file.remove();
        if (!newFile.rename(QdbdFileName))
            qWarning() << "Failed to save qdbd settings:" << newFile.errorString();

    } else {
        qWarning() << "Failed to save qdbd settings:" << file.errorString();
    }
}

void SettingsManager::reboot()
{
    sync();
    ::reboot(RB_AUTOBOOT);
    qWarning("reboot failed");
}