/*!
 *
 * Copyright (c) 2019-2020 Diality Inc. - All Rights Reserved.
 * \copyright                                                       \n
 *          THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM,  \n
 *          IN PART OR IN WHOLE,                                    \n
 *          WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER. \n
 *
 * \file    logger.cpp
 * \date    2019/09/30
 * \author  Behrouz NematiPour
 *
 */
#include "logger.h"

// Qt
#include <QDateTime>
#include <QDebug>
#include <QDir>
#include <QApplication>
#include <QtConcurrent/QtConcurrent>
#include <QFuture>

// Project
#include "DriveWatcher.h"
#include "threads.h"
#include "storageglobals.h"
#include "maintimer.h"
#include "filehandler.h"
#include "format.h"

using namespace Storage;

/*!
 * \brief Logger::Logger
 * \details Constructor
 * \param   parent - QObject parent owner object.
 *          Qt handles the children destruction by their parent objects life-cycle.
 */
Logger::Logger(QObject *parent) : QObject(parent) {
    _logFileNamePrefix = QFileInfo(qApp->applicationFilePath()).baseName();
}

/*!
 * \brief   Logger::init
 * \details Initializes the Class.
 * \return  False if it has been called before.
 */
bool Logger::init()
{
    if ( _init ) return false;
    _init = true;

    // runs in thread
    checkLogPath();
    initConnections();

    LOG_EVENT("UI," + tr("%1 Initialized").arg(metaObject()->className()));

    return true;
}

/*!
 * \brief   Logger::init
 * \details Initialized the Class by calling the init() method first
 *          And initializes the thread vThread by calling initThread
 *          on success init().
 * \param   vThread - the thread
 * \return  returns the return value of the init() method
 */
bool Logger::init(QThread &vThread)
{
    // coco begin validated: Application is not running in multi-threaded mode for testing
    // it has been tested and works perfectly fine in normal run.
    if ( ! init() ) return false;
    initThread(vThread);
    return true;
}
// coco end

/*!
 * \brief   Logger quit
 * \details quits the class
 *          Calls quitThread
 */
void Logger::quit()
{
    // coco begin validated: Application termination is not correctly done in coco!!!
    // it has been tested and works perfectly fine in normal run.
    quitThread(); // validated
}
// coco end

/*!
 * \brief   Logger::initConnections
 * \details Initializes the required signal/slot connection between this class and other objects
 *          to be able to communicate.
 * \note    No connection has been defined yet.
 */
void Logger::initConnections()
{
    connect(&_exportLogsWatcher, SIGNAL(finished    ()),
            this               ,   SLOT(onExportLogs()));

    connect(this, SIGNAL(didLog(QString,LogType)),
            this,   SLOT( onLog(QString,LogType)));


    connect(&_MainTimer, SIGNAL( didDateChange       ()),
            this       ,   SLOT( concurrentRemoveLogs()));

    connect(&_removeLogsWatcher, SIGNAL(finished    ()),
            this               ,   SLOT(onRemoveLogs()));

    connect(&_DriveWatcher, SIGNAL( didSDCardSpaceChange(bool, qint64, qint64, quint8)),
            this          ,   SLOT(  onSDCardSpaceChange(bool, qint64, qint64, quint8)));
}

/*!
 * \brief   Logger::initThread
 * \details Moves this object into the thread vThread.
 *          And checks that this method is called from main thread.
 *          Also connects quitThread to application aboutToQuit.
 * \param   vThread - the thread
 */
void Logger::initThread(QThread &vThread)
{
    // coco begin validated: Application is not running in multi-threaded mode for testing
    // it has been tested and works perfectly fine in normal run.
    // runs in main thread
    Q_ASSERT_X(QThread::currentThread() == qApp->thread() , __func__, "The Class initialization must be done in Main Thread" );
    _thread = &vThread;
    _thread->setObjectName(QString("%1_Thread").arg(metaObject()->className()));
    connect(qApp, SIGNAL(aboutToQuit()), this, SLOT(quit()));
    _thread->start();
    moveToThread(_thread);
}
// coco end
/*!
 * \brief   Logger::quitThread
 * \details Moves this object to main thread to be handled by QApplicaiton
 *          And to be destroyed there.
 */
void Logger::quitThread()
{
    // coco begin validated: Application termination is not correctly done in coco!!!
    // it has been tested and works perfectly fine in normal run.
    if (! _thread) return;

    // runs in thread
    moveToThread(qApp->thread()); // validated
}
// coco end

void Logger::onLog(const QString &vContent, LogType vLogType)
{
    log(vContent,vLogType);
}

/*!
 * \brief   Logger::checkLogPath
 * \details Sets the log paths and creates them if didn't exist.
 */
void Logger::checkLogPath()
{
    setLogBasePath();           // try to use /media/sd_card on device
    // coco begin validated: It can only happen if the file system is readonly for any reson.
    // it has been tested and works perfectly fine in normal run.
    if (! setLogPath()) {       // check and create log folders & if unsuccessful then
        // coco end
        setLogBasePath(true);   // try to use application folder
        setLogPath    (    );   // check and create log folders // Note: it may require to check for write access regarding device setup
    }
}

/*!
 * \brief   Logger::setLogBasePath
 * \details Tries to the set the log path to the default log path (Log_Base_Path_Name)
 *          Will set the application  folder as the base log path if can't set the log path to the default.
 *          Will log the event in that case.
 * \param   vUseApplicationDirPath
 */
void Logger::setLogBasePath(bool vUseApplicationDirPath)
{
    if (vUseApplicationDirPath) {
        _dir.setPath(qApp->applicationDirPath());
        // Don't use LOG_XXXXX, At this moment Logger has not been initialized yet
        qDebug() << QString("Application path used for events logging (%1)").arg(_dir.path());
    }
    else {
        _dir.setPath(SDCard_Base_Path_Name);
    }
}

/*!
 * \brief   Logger::setLogPath
 * \details set the log path for each of the Datum, Event, Error log types
 * \return  False if can not st the log paths.
 */
bool Logger::setLogPath()
{
    bool ok = true;
    if ( ok && ! setLogPath(LogType::eLogDebug) ) ok = false;
    if ( ok && ! setLogPath(LogType::eLogEvent) ) ok = false;
    if ( ok && ! setLogPath(LogType::eLogDatum) ) ok = false;
    return ok;
}

/*!
 * \brief   Logger::setLogPath
 * \details Sets the log path for the log type vLogType
 *          Creates the folder if not exists.
 * \param   vLogType - log type
 * \return  returns false if the path doesn't exist and folder can't be created.
 */
bool Logger::setLogPath(LogType vLogType)
{
    bool ok = false;
    switch (vLogType) {
    case LogType::eLogDebug:
        _logPathNames[vLogType] = qApp->applicationDirPath() + "/" + _logBasePathNames[vLogType];
        break;

    default:
        _logPathNames[vLogType] = _dir.path() + "/" + _logBasePathNames[vLogType];
        break;
    }
    ok = FileHandler::makeFolder(_logPathNames[vLogType]);
    return ok;
}

/*!
 * \brief   Logger::log
 * \details Logs the content vContent in log type of vLogType.
 * \param   vContent - Log content
 * \param   vLogType - Log type
 * \note    This method is not thread-safe so is private and needs to be called by concurrentLog
 *          Which uses QtConcurrent::run to run in thread and thread-safe.
 */
void Logger::log(const QString &vContent, LogType vLogType)
{
    QString date = QDate::currentDate().toString(_dateFormat);
    QString fileName = date + _dateSeparator + _logFileNamePrefix;
    switch (vLogType) {
    case LogType::eLogEvent:
    case LogType::eLogDatum:
    case LogType::eLogDebug:
        fileName += _logFileNameExt[vLogType];
        break;

    default:
        fileName += _logFileNameExt[eLogDebug];
        LOG_DEBUG(QString("Incorrect type of logging %1").arg(vLogType));
    }

    QString mContent = QTime::currentTime().toString(_timeFormat) + _separator;

    QString logPrefix = _logPrefix[vLogType];
    if ( ! logPrefix.isEmpty()) {
        mContent += logPrefix;
        mContent += _separator;
    }
    mContent += vContent;

    QString logPathName = _logPathNames[vLogType];
    if (logPathName.isEmpty())
        logPathName = _logPathNames[eLogDebug];
    _logFileName = logPathName + fileName;
    FileHandler::write(_logFileName, mContent + "\r\n", true);
    if (vLogType == eLogDebug) {
#ifdef QT_DEBUG
        //mContent.prepend("\033[1;31m --- @ --- \033[0m");
        mContent.prepend(" @ ");
#endif
        qDebug().noquote() << mContent;
    }
}


bool Logger::exportLogs()
{
    int result = 0;
    static QString mOSource;
    QString mDestination = USB_Mount_Point;
    for ( const auto &iType : { eLogEvent , eLogDatum } ) {
        QString mCSource = _logPathNames[iType];
        if (mOSource != mCSource) {
            mOSource  = mCSource;
            // Copy Folder
            result = FileHandler::copyFolder( mCSource, mDestination);
        }
    }
    mOSource = "";
    return result >= 0; // refer to QProcess::execute(hit F1 on execute) doc.
}

/*!
 * \brief   Logger::concurrentExportLogs
 * \details Exports the log files from log folder (Storage::Log_Base_Path_Name_Location)
 *          into USB drive folder (Storage::USB_Mount_Point)
 * \return  always returns true for now.
 * \note    This method uses QtConcurrent run to execute the FileHandler copyFolder method.
 */
bool Logger::concurrentExportLogs()
{
    // coco begin validated: This needs user interaction to export to USB device
    // has been tested manually
    LOG_DEBUG("Export Logs Start");
    QFuture<bool> future  = QtConcurrent::run(this, &Logger::exportLogs);
    _exportLogsWatcher.setFuture(future);
    return true;
}
// coco end

void Logger::onExportLogs()
{
    // coco begin validated: This needs user interaction to export to USB device
    // has been tested manually
    LOG_DEBUG(QString("Export Logs Ended: %1").arg(_exportLogsWatcher.result()));
    emit didExportLogs();
}
// coco end

/*!
 * \brief   Logger::removeLogs
 * \details Remove old logs by iterating in the log/service folders and look for expired logs.
 * \return  count file(s) have been removed.
 */
int Logger::removeLogs()
{
    // coco begin validated: This needs user interaction to check the old files deleted
    // has been tested manually
    static QString mOSource;
    int countRemoved = 0;
    QStringList  mLogFileFilter;
    QDate        mOlderThan    ;
    for ( const auto &iType : { eLogEvent , eLogDatum , eLogDebug } ) {
        QString mCSource = _logPathNames[iType];
        if (mOSource != mCSource) {
            mOSource  = mCSource;
            // Remove Logs
            if (_logTypeExpiryDay.value(iType)) {
                mOlderThan      = QDate().currentDate().addDays( _logTypeExpiryDay.value(iType) * -1 /*Please Notice (-1)*/ );
                mLogFileFilter  = Format::toStringList(_logFileNameExt  .values(iType), true, "*");
                LOG_DEBUG(QString("Removing logs older than %1 from folder %2").arg(mOlderThan.toString("yyyy-MM-dd")).arg(mCSource));
                countRemoved   += FileHandler::removeFiles({ mCSource }, mLogFileFilter, mOlderThan);
            }
            else {
                LOG_DEBUG("Current day logs cannot be deletet");
            }
        }
    }
    mOSource = "";
    return countRemoved;
}
// coco end

/*!
 * \brief   Logger::concurrentRemoveLogs
 * \details
 *
 * \return  always returns true for now.
 * \note    This method uses QtConcurrent run to execute the FileHandler copyFolder method.
 */
bool Logger::concurrentRemoveLogs()
{
    // coco begin validated: This needs user interaction to check the old files deleted
    // has been tested manually
    LOG_DEBUG("Remove Logs Start");
    QFuture<int> mFuture = QtConcurrent::run(this,&Logger::removeLogs);
    _removeLogsWatcher.setFuture(mFuture);
    return true;
}
// coco end

void Logger::onRemoveLogs()
{
    // coco begin validated: This needs user interaction to export to USB device
    // has been tested manually
    LOG_DEBUG(QString("Remove Logs Ended: %1").arg(_removeLogsWatcher.result()));
    emit didRemoveLogs();
}

void Logger::onSDCardSpaceChange(bool vReady, qint64 vTotal, qint64 vAvailable, quint8 vPercent)
{
    if (vPercent < _availableSpacePercent ) {
        concurrentRemoveLogs();
        qDebug() << 0 << vReady << vTotal << vAvailable << vPercent;
    }
    else {
        qDebug() << 1 << vReady << vTotal << vAvailable << vPercent;
    }
}
// coco end