/*!
 *
 * Copyright (c) 2021-2022 Diality Inc. - All Rights Reserved.
 * \copyright
 * THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
 * WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
 *
 * \file    Settings.cpp
 * \author  (last)      Behrouz NematiPour
 * \date    (last)      15-Aug-2022
 * \author  (original)  Behrouz NematiPour
 * \date    (original)  29-Mar-2021
 *
 */

// Qt
#include <QFileInfo>
#include <QStorageInfo>
#include <QSettings>

// Project
#include "StorageGlobals.h"
#include "FileHandler.h"
#include "MSettings.h"
#include "Logger.h"

// namespace
using namespace Storage;

#include "Settings.h"

bool Settings::isValid(const QString &vSettingFile)
{
    if (! QFileInfo::exists(vSettingFile)) {
        LOG_DEBUG("Setting file " + vSettingFile + " does not exist.");
        return false;
    }
    return true;
}

/*!
 * \brief   Settings::fileName
 * \details returns the conf file by the settings information provided.
 * \return  QString configuration/settings file name
 */
QString Settings::fileName(const QString &vCategory) {
    return QString("%1%2.%3").arg(Storage::Settings_Path_Name).arg(vCategory).arg(_settingsExt);
}

/*!
 * \brief   Settings::doRead
 * \details Reads all the configuration files
 */
int Settings::read()
{
    QStringList     fileFilter      = QStringList() << QString("*.%1").arg(_settingsExt);
    QFileInfoList   settingFiles    = FileHandler::find      (Storage::Settings_Path_Name, fileFilter);
    QStringList     settingFolders  = FileHandler::subFolders(Storage::Settings_Path_Name);

    if ( ! settingFolders.count() ) {
        LOG_DEBUG(QObject::tr("No setting folder in the %1").arg(Storage::Settings_Path_Name));
        return 1; // TODO : Define an error enum when completed
    }

    for ( QString &settingFolder : settingFolders ) {
        QString folder = settingFolder.prepend(Storage::Settings_Path_Name);
        settingFiles += FileHandler::find(folder, fileFilter);
    }
    // DEBUG:
    // settingFiles =
    // {
    //     QFileInfo("/home/denali/Projects/application/resources/settings/Confirm/Confirm.conf"),
    //     QFileInfo("/home/denali/Projects/application/resources/settings/Alarms/Alarms.conf")
    // };
    if ( ! settingFiles.count() ) {
        LOG_DEBUG(QObject::tr("No setting files in the %1").arg(Storage::Settings_Path_Name));
        return 2; // TODO : Define an error enum when completed
    }

    QList<Detail> details;
    for (const auto &settingFile: settingFiles) {
        if (! isValid(settingFile.absoluteFilePath())) continue;

        QFile file(settingFile.absoluteFilePath());
        if (file.open(QIODevice::ReadOnly | QIODevice::Text)) {
            Detail detail;
            detail.content    = file.readAll().trimmed();
            if (detail.content.isEmpty()) continue;
            detail.location   = settingFile.absolutePath() + "/";
            detail.category   = QString(detail.location + settingFile.baseName()).remove(Storage::Settings_Path_Name);
            details += detail;
        }
    }

    for (const auto &detail : details) {
        bool    enableDuplicateKey = false;
        QString attribute = QString("%1%2").arg(_config_attribute_tag);
        QString group = "";
        QStringList lines = detail.content.split('\n');
        for (QString line : lines) {
            // ----- trim the line
            line = line.trimmed();

            // ----- ignore empty lines
            if ( line.isEmpty() ) continue;

            // ----- find comments
            int  commentPosition  = line.indexOf('#');


            // ----- ignore comment line or find attributes
            if ( commentPosition == 0 ) {

                // ----- find the configuration file attribute
                int  attributeTagPosition = line.indexOf(_config_attribute_tag);
                if ( attributeTagPosition == 0 ) {

                    // ----- find the attribute : duplicate_key_...
                    if      ( line == attribute.arg( _duplicate_key_on ) ) { enableDuplicateKey = true  ;}
                    else if ( line == attribute.arg(_duplicate_key_off ) ) { enableDuplicateKey = false ;}

                    else    {
                        LOG_APPED_UI(( "Unknown '" + line + "' attribute in %1").arg(detail.category));
                    }
                }

                // next line
                continue;
            }

            // ----- remove inline comment
            if ( commentPosition  > 0 ) line.truncate(commentPosition);
            line = line.trimmed();

            // ----- find group
            if (line.contains("[") && line.contains("]")) {
                line.replace("[","").replace("]", "");
                group = line;
            }
            else {
                if ( group.isEmpty() ) {
                    continue;
                }
                else {
                    if ( ! line.isEmpty() ) {
                        QString key   = "";
                        QString value = "";
                        if ( line.contains('=') ) {
                            QStringList keyValue = line.split('=');
                            key     = keyValue[0].trimmed().replace("\\n","\n");
                            value   = keyValue[1].trimmed().replace("\\n","\n");
                        }
                        else {
                            key     = line;
                        }
                        _Settings.add(detail.category, group, key, QVariant(value), enableDuplicateKey);
                        // DEBUG: qDebug() << group << key << value << location << category;
                    }
                }
            }
            // DEBUG: qDebug() << group << line;
        }
    }
    return 0;
}

/*!
 * \brief   Settings::save
 * \details Writes the setting in the configuration files
 * \return
 */
int Settings::save(const QString &vCategory, const QString &vGroup, const QString &vKey, const QString &vValue)
{
    // qDebug() << vCategory
    //          << vGroup
    //          << vKey
    //          << vValue;
    QString mFileName = fileName(vCategory);
    QString mContent;
    // --------------------------------------------------------------------------------------------------------------
    //Note: the configuration files which can be saved, are like settings and should not have duplicate values.
    //      as an example the Alarm volume can't have two separate duplicate entry in the settings.
    // --------------------------------------------------------------------------------------------------------------
    _Settings.add(vCategory, vGroup, vKey, vValue, false);
    QString mPath = QFileInfo(mFileName).absolutePath();
    if ( mPath.trimmed().isEmpty() ) {
        LOG_DEBUG("The settings path is empty.");
        return 1; // TODO: define enum
    }

    if ( ! FileHandler::makeFolder(mPath) ) {
        LOG_DEBUG(QString("The settings path %1 can't be created.").arg(mPath));
        return 2; // TODO: define enum
    }

    for ( const auto &group : _Settings.groups(vCategory) ) {
        mContent += QString("\n[%1]\n").arg(group);
        for ( const auto &key : _Settings.keys(vCategory, group) ) {
            mContent += QString("%1 = %2\n").arg(key).arg(_Settings.value(vCategory, group, key).toString());
        }
    }

    if ( ! FileHandler::write(mFileName,mContent, false) ) {
        LOG_DEBUG(QString("The settings file %1 can't be written.").arg(mFileName));
        return 3; // TODO: define enum
    }

    return 0;
}