Continue to improve functions.

Split source files that are too long.

14 files changed, 1036 insertions, 729 deletions

diff --git a/include/gpg/GpgContext.h b/include/gpg/GpgContext.h
index ac01c532..858566d5 100644
--- a/include/gpg/GpgContext.h
+++ b/include/gpg/GpgContext.h
@@ -190,14 +190,14 @@ namespace GpgME {
         bool debug;
         bool good = true;
 
-        static gpgme_error_t readToBuffer(gpgme_data_t dataIn, QByteArray *outBuffer);
-
         QByteArray mPasswordCache;
         QSettings settings;
         GpgKeyList mKeyList;
 
         QMap<QString, GpgKey *> mKeyMap;
 
+        static gpgme_error_t readToBuffer(gpgme_data_t dataIn, QByteArray *outBuffer);
+
         void fetch_keys();
 
         static void checkErr(gpgme_error_t gpgmeError);
diff --git a/include/gpg/GpgKeySignature.h b/include/gpg/GpgKeySignature.h
index 05a212a7..0dd2f893 100644
--- a/include/gpg/GpgKeySignature.h
+++ b/include/gpg/GpgKeySignature.h
@@ -54,9 +54,12 @@ struct GpgKeySignature {
     explicit GpgKeySignature(gpgme_key_sig_t key_sig);
 
     GpgKeySignature(GpgKeySignature &&) noexcept = default;
+
     GpgKeySignature(const GpgKeySignature &) = default;
-    GpgKeySignature& operator=(GpgKeySignature &&) noexcept = default;
-    GpgKeySignature& operator=(const GpgKeySignature &) = default;
+
+    GpgKeySignature &operator=(GpgKeySignature &&) noexcept = default;
+
+    GpgKeySignature &operator=(const GpgKeySignature &) = default;
 
 };
 
diff --git a/include/server/ComUtils.h b/include/server/ComUtils.h
index 64f80e87..5f27998e 100644
--- a/include/server/ComUtils.h
+++ b/include/server/ComUtils.h
@@ -32,16 +32,24 @@ class ComUtils : public QWidget {
 Q_OBJECT
 public:
 
+    enum ServiceType { GetServiceToken, ShortenCryptText, GetFullCryptText };
+
     explicit ComUtils(QWidget *parent) : QWidget(parent), appPath(qApp->applicationDirPath()),
                                          settings(RESOURCE_DIR(appPath) + "/conf/gpgfrontend.ini",
                                                   QSettings::IniFormat) {
 
     }
 
+    QString getUrl(ServiceType type);
+
     bool checkServerReply(const QByteArray &reply);
 
     QString getDataValue(const QString &key);
 
+    bool checkDataValue(const QString &key);
+
+    bool checkServiceTokenFormat(const QString& serviceToken);
+
     [[nodiscard]] bool good() const { return is_good; }
 
 private:
@@ -50,6 +58,9 @@ private:
     QSettings settings;
     rapidjson::Document replyDoc;
     rapidjson::Value dataVal;
+
+    QRegularExpression re_uuid{R"(\b[0-9a-f]{8}\b-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-\b[0-9a-f]{12}\b)"};
+
     bool is_good = false;
 };
 
diff --git a/include/ui/SettingsDialog.h b/include/ui/SettingsDialog.h
index 358ab2d1..2f289a4c 100755
--- a/include/ui/SettingsDialog.h
+++ b/include/ui/SettingsDialog.h
@@ -58,10 +58,6 @@ private:
 
     QNetworkAccessManager manager;
 
-    QRegularExpression re_uuid{R"(\b[0-9a-f]{8}\b-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-\b[0-9a-f]{12}\b)"};
-
-    bool checkUUIDFormat(const QString& uuid);
-
 private slots:
 
     void slotOwnKeyIdChanged();
diff --git a/resource/conf/gpgfrontend.ini b/resource/conf/gpgfrontend.ini
index 3fc1c1b8..fc7c0c2b 100644
--- a/resource/conf/gpgfrontend.ini
+++ b/resource/conf/gpgfrontend.ini
@@ -15,3 +15,38 @@ showWizard=true
 windowState=@ByteArray(\0\0\0\xff\0\0\0\0\xfd\0\0\0\x2\0\0\0\x1\0\0\x1\xcc\0\0\x2V\xfc\x2\0\0\0\x1\xfb\0\0\0\x16\0\x45\0n\0\x63\0r\0y\0p\0t\0\x44\0o\0\x63\0k\x1\0\0\0I\0\0\x2V\0\0\0]\0\xff\xff\xff\0\0\0\x3\0\0\x2\xe0\0\0\0\xf5\xfc\x1\0\0\0\x1\xfb\0\0\0\"\0I\0n\0\x66\0o\0r\0m\0\x61\0t\0i\0o\0n\0 \0\x42\0o\0\x61\0r\0\x64\x1\0\0\0\0\0\0\x2\xe0\0\0\x1\xe0\0\xff\xff\xff\0\0\x2\xe0\0\0\x1]\0\0\0\x4\0\0\0\x4\0\0\0\x1\0\0\0\x2\xfc\0\0\0\x1\0\0\0\x2\0\0\0\x5\0\0\0\x16\0\x66\0i\0l\0\x65\0T\0o\0o\0l\0\x42\0\x61\0r\0\0\0\0\0\xff\xff\xff\xff\0\0\0\0\0\0\0\0\0\0\0\x18\0\x63\0r\0y\0p\0t\0T\0o\0o\0l\0\x42\0\x61\0r\x1\0\0\0\0\xff\xff\xff\xff\0\0\0\0\0\0\0\0\0\0\0\x14\0k\0\x65\0y\0T\0o\0o\0l\0\x42\0\x61\0r\x1\0\0\x1z\xff\xff\xff\xff\0\0\0\0\0\0\0\0\0\0\0\x16\0\x65\0\x64\0i\0t\0T\0o\0o\0l\0\x42\0\x61\0r\x1\0\0\x2\f\xff\xff\xff\xff\0\0\0\0\0\0\0\0\0\0\0$\0s\0p\0\x65\0\x63\0i\0\x61\0l\0\x45\0\x64\0i\0t\0T\0o\0o\0l\0\x42\0\x61\0r\0\0\0\0\0\xff\xff\xff\xff\0\0\0\0\0\0\0\0)
 pos=@Point(100 100)
 size=@Size(1200 700)
+windowSave=false
+
+[advanced]
+steganography=false
+
+[gpgpaths]
+keydbpath=.
+
+[sendMail]
+smtpAddress=
+username=
+password=
+port=25
+connectionType=None
+defaultSender=
+enable=false
+
+[toolbar]
+iconsize=@Size(24 24)
+iconstyle=3
+
+[%General]
+currentGpgfrontendServer=service.gpgfrontend.pub
+gpgfrontendServerList=service.gpgfrontend.pub, localhost
+ownKeyId=
+serviceToken=
+confirmImportKeys=true
+
+[keymgmt]
+pos=@Point(100 100)
+size=@Size(900 600)
+setWindowSize=true
+
+[informationBoard]
+fontSize=10
\ No newline at end of file
diff --git a/src/server/ComUtils.cpp b/src/server/ComUtils.cpp
index 637b5c12..25d471af 100644
--- a/src/server/ComUtils.cpp
+++ b/src/server/ComUtils.cpp
@@ -31,11 +31,14 @@
  */
 bool ComUtils::checkServerReply(const QByteArray &reply) {
 
+    qDebug() << "Reply" << reply;
+
     /**
      * Server Reply Format(Except Timeout)
      * {
      *      "status": 200,
-     *      "message": "OK",
+     *      "msg": "OK",
+     *      "timestamp": 1628652783895
      *      "data" : {
      *          ...
      *      }
@@ -49,21 +52,40 @@ bool ComUtils::checkServerReply(const QByteArray &reply) {
     }
 
     // check status(int) and message(string)
-    if (replyDoc.HasMember("status") && replyDoc.HasMember("message")
-        && replyDoc["status"].IsInt() && replyDoc["message"].IsString()) {
+    if (replyDoc.HasMember("status") && replyDoc.HasMember("msg") && replyDoc.HasMember("timestamp") &&
+        replyDoc.HasMember("data")
+        && replyDoc["status"].IsNumber() && replyDoc["msg"].IsString() && replyDoc["timestamp"].IsNumber() &&
+        replyDoc["data"].IsObject()) {
 
         int status = replyDoc["status"].GetInt();
-        QString message = replyDoc["status"].GetString();
+        QDateTime time;
+        time.setMSecsSinceEpoch(replyDoc["timestamp"].GetInt64());
+        auto message = replyDoc["msg"].GetString();
+        dataVal = replyDoc["data"].GetObjectA();
+
+        qDebug() << "Reply Date & Time" << time;
+
+        // check reply timestamp
+        if (time < QDateTime::currentDateTime().addSecs(-10)) {
+            QMessageBox::critical(this, tr("Network Error"), tr("Outdated Reply"));
+            return false;
+        }
 
         // check status code if successful (200-299)
         // check data object
-        if (status / 10 == 2 && replyDoc.HasMember("data") && replyDoc["data"].IsObject()) {
-            dataVal = replyDoc["data"].GetObjectA();
+        if (status / 100 == 2) {
             is_good = true;
             return true;
-        } else QMessageBox::critical(this, tr("Error"), message);
+        } else  {
+            dataVal = replyDoc["data"].GetObjectA();
+            if (dataVal.HasMember("exceptionMessage") && dataVal["exceptionMessage"].IsString())
+                QMessageBox::critical(this, message, dataVal["exceptionMessage"].GetString());
+            else QMessageBox::critical(this, message, tr("Unknown Reason"));
+        }
+
+    } else QMessageBox::critical(this, tr("Network Error"), tr("Unknown Reply Format"));
 
-    } else QMessageBox::critical(this, tr("Error"), tr("Unknown Reply Format"));
+    return false;
 }
 
 /**
@@ -79,3 +101,47 @@ QString ComUtils::getDataValue(const QString &key) {
         } else return {};
     } else return {};
 }
+
+/**
+ * Get eventually url by service type
+ * @param type service which server provides
+ * @return url
+ */
+QString ComUtils::getUrl(ComUtils::ServiceType type) {
+    auto host = settings.value("general/currentGpgfrontendServer",
+                               "service.gpgfrontend.pub").toString();
+
+    auto protocol = QString();
+    // Debug Server
+    if (host == "localhost") protocol = "http://";
+    else protocol = "https://";
+
+    auto url = protocol + host + "/";
+
+    switch (type) {
+        case GetServiceToken:
+            url += "/user";
+            break;
+        case ShortenCryptText:
+            url += "/text/new";
+            break;
+        case GetFullCryptText:
+            url += "/text/get";
+            break;
+    }
+
+    qDebug() << "ComUtils getUrl" << url;
+
+    return url;
+}
+
+bool ComUtils::checkDataValue(const QString &key) {
+    auto key_byte_array_data = key.toUtf8().constData();
+    if (is_good) {
+        return dataVal.HasMember(key_byte_array_data) && dataVal[key_byte_array_data].IsString();
+    } else return false;
+}
+
+bool ComUtils::checkServiceTokenFormat(const QString &uuid) {
+    return re_uuid.match(uuid).hasMatch();
+}
diff --git a/src/ui/CMakeLists.txt b/src/ui/CMakeLists.txt
index 618b5d28..b6552227 100644
--- a/src/ui/CMakeLists.txt
+++ b/src/ui/CMakeLists.txt
@@ -4,6 +4,7 @@ aux_source_directory(./widgets UI_SOURCE)
 aux_source_directory(./keygen UI_SOURCE)
 aux_source_directory(./main_window UI_SOURCE)
 aux_source_directory(./help UI_SOURCE)
+aux_source_directory(./settings UI_SOURCE)
 
 add_library(gpgfrontend-ui STATIC ${UI_SOURCE})
 
diff --git a/src/ui/SettingsDialog.cpp b/src/ui/SettingsDialog.cpp
index 00b26e7b..d110a64a 100755
--- a/src/ui/SettingsDialog.cpp
+++ b/src/ui/SettingsDialog.cpp
@@ -23,12 +23,8 @@
  */
 
 #include "ui/SettingsDialog.h"
-#include "smtp/SmtpMime"
 #include "ui/WaitingDialog.h"
 
-#include "rapidjson/document.h"
-#include "rapidjson/prettywriter.h"
-
 SettingsDialog::SettingsDialog(GpgME::GpgContext *ctx, QWidget *parent)
         : QDialog(parent) {
     mCtx = ctx;
@@ -128,689 +124,6 @@ QHash<QString, QString> SettingsDialog::listLanguages() {
     return languages;
 }
 
-GeneralTab::GeneralTab(GpgME::GpgContext *ctx, QWidget *parent)
-        : QWidget(parent), appPath(qApp->applicationDirPath()),
-          settings(RESOURCE_DIR(appPath) + "/conf/gpgfrontend.ini",
-                   QSettings::IniFormat) {
-    mCtx = ctx;
-
-    /*****************************************
-     * GpgFrontend Server
-     *****************************************/
-    auto *serverBox = new QGroupBox(tr("GpgFrontend Server"));
-    auto *serverBoxLayout = new QVBoxLayout();
-    serverSelectBox = new QComboBox();
-    serverBoxLayout->addWidget(serverSelectBox);
-    serverBoxLayout->addWidget(new QLabel(
-            tr("Server that provides short key and key exchange services")));
-    serverBox->setLayout(serverBoxLayout);
-
-    /*****************************************
-     * Save-Checked-Keys-Box
-     *****************************************/
-    auto *saveCheckedKeysBox = new QGroupBox(tr("Save Checked Keys"));
-    auto *saveCheckedKeysBoxLayout = new QHBoxLayout();
-    saveCheckedKeysCheckBox = new QCheckBox(
-            tr("Save checked private keys on exit and restore them on next start."),
-            this);
-    saveCheckedKeysBoxLayout->addWidget(saveCheckedKeysCheckBox);
-    saveCheckedKeysBox->setLayout(saveCheckedKeysBoxLayout);
-
-    /*****************************************
-     * Key-Impport-Confirmation Box
-     *****************************************/
-    auto *importConfirmationBox =
-            new QGroupBox(tr("Confirm drag'n'drop key import"));
-    auto *importConfirmationBoxLayout = new QHBoxLayout();
-    importConfirmationCheckBox = new QCheckBox(
-            tr("Import files dropped on the keylist without confirmation."), this);
-    importConfirmationBoxLayout->addWidget(importConfirmationCheckBox);
-    importConfirmationBox->setLayout(importConfirmationBoxLayout);
-
-    /*****************************************
-     * Language Select Box
-     *****************************************/
-    auto *langBox = new QGroupBox(tr("Language"));
-    auto *langBoxLayout = new QVBoxLayout();
-    langSelectBox = new QComboBox;
-    lang = SettingsDialog::listLanguages();
-
-    for (const auto &l: lang) { langSelectBox->addItem(l); }
-
-    langBoxLayout->addWidget(langSelectBox);
-    langBoxLayout->addWidget(
-            new QLabel(tr("<b>NOTE: </b> GpgFrontend will restart automatically if "
-                          "you change the language!")));
-    langBox->setLayout(langBoxLayout);
-    connect(langSelectBox, SIGNAL(currentIndexChanged(int)), this,
-            SLOT(slotLanguageChanged()));
-
-    /*****************************************
-     * Own Key Select Box
-     *****************************************/
-    auto *ownKeyBox = new QGroupBox(tr("Own key"));
-    auto *ownKeyBoxLayout = new QVBoxLayout();
-    auto *ownKeyServiceTokenLayout = new QHBoxLayout();
-    ownKeySelectBox = new QComboBox;
-    getServiceTokenButton = new QPushButton(tr("Get Service Token"));
-    serviceTokenLabel = new QLabel(tr("No Service Token Found"));
-
-    ownKeyBox->setLayout(ownKeyBoxLayout);
-    mKeyList = new KeyList(mCtx);
-
-    // Fill the keyid hashmap
-    keyIds.insert("", tr("<none>"));
-
-    for (const auto &keyid : *mKeyList->getAllPrivateKeys()) {
-        auto &key = mCtx->getKeyById(keyid);
-        keyIds.insert(key.id, key.uids.first().uid);
-    }
-    for (const auto &k : keyIds.keys()) {
-        ownKeySelectBox->addItem(keyIds.find(k).value());
-        keyIdsList.append(k);
-    }
-    connect(ownKeySelectBox, SIGNAL(currentIndexChanged(int)), this,
-            SLOT(slotOwnKeyIdChanged()));
-    connect(getServiceTokenButton, SIGNAL(clicked(bool)), this,
-            SLOT(slotGetServiceToken()));
-
-    ownKeyBoxLayout->addWidget(new QLabel(
-            tr("Key pair for synchronization and identity authentication")));
-    ownKeyBoxLayout->addWidget(ownKeySelectBox);
-    ownKeyBoxLayout->addLayout(ownKeyServiceTokenLayout);
-    ownKeyServiceTokenLayout->addWidget(getServiceTokenButton);
-    ownKeyServiceTokenLayout->addWidget(serviceTokenLabel);
-    ownKeyServiceTokenLayout->stretch(0);
-
-    /*****************************************
-     * Mainlayout
-     *****************************************/
-    auto *mainLayout = new QVBoxLayout;
-    mainLayout->addWidget(serverBox);
-    mainLayout->addWidget(saveCheckedKeysBox);
-    mainLayout->addWidget(importConfirmationBox);
-    mainLayout->addWidget(langBox);
-    mainLayout->addWidget(ownKeyBox);
-
-    setSettings();
-    mainLayout->addStretch(1);
-    setLayout(mainLayout);
-}
-
-/**********************************
- * Read the settings from config
- * and set the buttons and checkboxes
- * appropriately
- **********************************/
-void GeneralTab::setSettings() {
-    // Keysaving
-    if (settings.value("keys/saveKeyChecked").toBool()) {
-        saveCheckedKeysCheckBox->setCheckState(Qt::Checked);
-    }
-
-    auto serverList = settings.value("general/gpgfrontendServerList").toStringList();
-    if(serverList.empty()) {
-        serverList.append("service.gpgfrontend.pub");
-    }
-    for(const auto &s : serverList)
-        serverSelectBox->addItem(s);
-    serverSelectBox->setCurrentText(settings.value("general/currentGpgfrontendServer",
-                                                   "service.gpgfrontend.pub").toString());
-
-    // Language setting
-    QString langKey = settings.value("int/lang").toString();
-    QString langValue = lang.value(langKey);
-    if (langKey != "") {
-        langSelectBox->setCurrentIndex(langSelectBox->findText(langValue));
-    }
-
-    QString own_key_id = settings.value("general/ownKeyId").toString();
-    qDebug() << "OwnKeyId" << own_key_id;
-    if (own_key_id.isEmpty()) {
-        ownKeySelectBox->setCurrentText("<none>");
-    } else {
-        const auto text = keyIds.find(own_key_id).value();
-        qDebug() << "OwnKey" << own_key_id << text;
-        ownKeySelectBox->setCurrentText(text);
-    }
-
-    serviceToken = settings.value("general/serviceToken").toString();
-    qDebug() << "Load Service Token" << serviceToken;
-    if(!serviceToken.isEmpty()) {
-        serviceTokenLabel->setText(serviceToken);
-    }
-
-    // Get own key information from keydb/gpg.conf (if contained)
-    if (settings.value("general/confirmImportKeys", Qt::Checked).toBool()) {
-        importConfirmationCheckBox->setCheckState(Qt::Checked);
-    }
-}
-
-/***********************************
- * get the values of the buttons and
- * write them to settings-file
- *************************************/
-void GeneralTab::applySettings() {
-    settings.setValue("keys/saveKeyChecked",
-                      saveCheckedKeysCheckBox->isChecked());
-
-    settings.setValue("general/currentGpgfrontendServer",
-                      serverSelectBox->currentText());
-
-    auto *serverList = new QStringList();
-    for(int i = 0; i < serverSelectBox->count(); i++)
-        serverList->append(serverSelectBox->itemText(i));
-    settings.setValue("general/gpgfrontendServerList",
-                      *serverList);
-    delete serverList;
-
-    settings.setValue("int/lang", lang.key(langSelectBox->currentText()));
-
-    settings.setValue("general/ownKeyId",
-                      keyIdsList[ownKeySelectBox->currentIndex()]);
-
-    settings.setValue("general/serviceToken",
-                     serviceToken);
-
-    settings.setValue("general/confirmImportKeys",
-                      importConfirmationCheckBox->isChecked());
-}
-
-void GeneralTab::slotLanguageChanged() { emit signalRestartNeeded(true); }
-
-void GeneralTab::slotOwnKeyIdChanged() {
-    // Set ownKeyId to currently selected
-    this->serviceTokenLabel->setText(tr("No Service Token Found"));
-    serviceToken.clear();
-}
-
-void GeneralTab::slotGetServiceToken() {
-    QUrl reqUrl("http://127.0.0.1:9048/user");
-    QNetworkRequest request(reqUrl);
-    request.setHeader(QNetworkRequest::ContentTypeHeader, "application/json");
-
-    // Building Post Data
-    QByteArray keyDataBuf;
-
-    const auto keyId = keyIdsList[ownKeySelectBox->currentIndex()];
-
-    qDebug() << "KeyId" << keyIdsList[ownKeySelectBox->currentIndex()];
-
-    if(keyId.isEmpty()) {
-        QMessageBox::critical(this, tr("Invalid Operation"), tr("Own Key can not be None while getting service token."));
-        return;
-    }
-
-    QStringList selectedKeyIds(keyIdsList[ownKeySelectBox->currentIndex()]);
-    mCtx->exportKeys(&selectedKeyIds, &keyDataBuf);
-
-    qDebug() << "keyDataBuf" << keyDataBuf;
-
-    rapidjson::Value p, v;
-
-    rapidjson::Document doc;
-    doc.SetObject();
-
-    p.SetString(keyDataBuf.constData(), keyDataBuf.count());
-
-    auto version = qApp->applicationVersion();
-    v.SetString(version.toUtf8().constData(), qApp->applicationVersion().count());
-
-    doc.AddMember("publicKey", p, doc.GetAllocator());
-    doc.AddMember("version", v, doc.GetAllocator());
-
-    rapidjson::StringBuffer sb;
-    rapidjson::PrettyWriter<rapidjson::StringBuffer> writer(sb);
-    doc.Accept(writer);
-
-    QByteArray postData(sb.GetString());
-
-    QNetworkReply *reply = manager.post(request, postData);
-
-    auto dialog = new WaitingDialog("Getting Token From Server", this);
-    dialog->show();
-
-    while (reply->isRunning()) {
-        QApplication::processEvents();
-    }
-
-    dialog->close();
-
-    if(reply->error() == QNetworkReply::NoError) {
-        rapidjson::Document docReply;
-        docReply.Parse(reply->readAll().constData());
-        QString serviceTokenTemp = docReply["serviceToken"].GetString();
-        if(checkUUIDFormat(serviceTokenTemp)) {
-            serviceToken = serviceTokenTemp;
-            qDebug() << "Get Service Token" << serviceToken;
-            serviceTokenLabel->setText(serviceToken);
-        } else {
-            QMessageBox::critical(this, tr("Error"), tr("Invalid Service Token Format"));
-        }
-    } else {
-        QMessageBox::critical(this, tr("Error"), reply->errorString());
-    }
-
-}
-
-bool GeneralTab::checkUUIDFormat(const QString& uuid) {
-    return re_uuid.match(uuid).hasMatch();
-}
-
-SendMailTab::SendMailTab(QWidget *parent)
-        : QWidget(parent), appPath(qApp->applicationDirPath()),
-          settings(RESOURCE_DIR(appPath) + "/conf/gpgfrontend.ini",
-                   QSettings::IniFormat) {
-
-    enableCheckBox = new QCheckBox(tr("Enable"));
-    enableCheckBox->setTristate(false);
-
-    smtpAddress = new QLineEdit();
-    username = new QLineEdit();
-    password = new QLineEdit();
-    password->setEchoMode(QLineEdit::Password);
-
-    portSpin = new QSpinBox();
-    portSpin->setMinimum(1);
-    portSpin->setMaximum(65535);
-    connectionTypeComboBox = new QComboBox();
-    connectionTypeComboBox->addItem("None");
-    connectionTypeComboBox->addItem("SSL");
-    connectionTypeComboBox->addItem("TLS");
-    connectionTypeComboBox->addItem("STARTTLS");
-
-    defaultSender = new QLineEdit();;
-    checkConnectionButton = new QPushButton(tr("Check Connection"));
-
-    auto layout = new QGridLayout();
-    layout->addWidget(enableCheckBox, 0, 0);
-    layout->addWidget(new QLabel(tr("SMTP Address")), 1, 0);
-    layout->addWidget(smtpAddress, 1, 1, 1, 4);
-    layout->addWidget(new QLabel(tr("Username")), 2, 0);
-    layout->addWidget(username, 2, 1, 1, 4);
-    layout->addWidget(new QLabel(tr("Password")), 3, 0);
-    layout->addWidget(password, 3, 1, 1, 4);
-    layout->addWidget(new QLabel(tr("Port")), 4, 0);
-    layout->addWidget(portSpin, 4, 1, 1, 1);
-    layout->addWidget(new QLabel(tr("Connection Security")), 5, 0);
-    layout->addWidget(connectionTypeComboBox, 5, 1, 1, 1);
-
-    layout->addWidget(new QLabel(tr("Default Sender")), 6, 0);
-    layout->addWidget(defaultSender, 6, 1, 1, 4);
-    layout->addWidget(checkConnectionButton, 7, 0);
-
-    connect(enableCheckBox, SIGNAL(stateChanged(int)), this, SLOT(slotCheckBoxSetEnableDisable(int)));
-    connect(checkConnectionButton, SIGNAL(clicked(bool)), this, SLOT(slotCheckConnection()));
-
-
-    this->setLayout(layout);
-    setSettings();
-}
-
-/**********************************
- * Read the settings from config
- * and set the buttons and checkboxes
- * appropriately
- **********************************/
-void SendMailTab::setSettings() {
-
-    if (settings.value("sendMail/enable", false).toBool())
-        enableCheckBox->setCheckState(Qt::Checked);
-    else {
-        enableCheckBox->setCheckState(Qt::Unchecked);
-        smtpAddress->setDisabled(true);
-        username->setDisabled(true);
-        password->setDisabled(true);
-        portSpin->setDisabled(true);
-        connectionTypeComboBox->setDisabled(true);
-        defaultSender->setDisabled(true);
-        checkConnectionButton->setDisabled(true);
-    }
-
-    smtpAddress->setText(settings.value("sendMail/smtpAddress", QString()).toString());
-    username->setText(settings.value("sendMail/username", QString()).toString());
-    password->setText(settings.value("sendMail/password", QString()).toString());
-    portSpin->setValue(settings.value("sendMail/port", 25).toInt());
-    connectionTypeComboBox->setCurrentText(settings.value("sendMail/connectionType", "None").toString());
-    defaultSender->setText(settings.value("sendMail/defaultSender", QString()).toString());
-
-}
-
-/***********************************
- * get the values of the buttons and
- * write them to settings-file
- *************************************/
-void SendMailTab::applySettings() {
-
-    settings.setValue("sendMail/smtpAddress", smtpAddress->text());
-    settings.setValue("sendMail/username", username->text());
-    settings.setValue("sendMail/password", password->text());
-    settings.setValue("sendMail/port", portSpin->value());
-    settings.setValue("sendMail/connectionType", connectionTypeComboBox->currentText());
-    settings.setValue("sendMail/defaultSender", defaultSender->text());
-
-    settings.setValue("sendMail/enable", enableCheckBox->isChecked());
-}
-
-void SendMailTab::slotCheckConnection() {
-
-    SmtpClient::ConnectionType connectionType;
-    const auto selectedConnType = connectionTypeComboBox->currentText();
-    if (selectedConnType == "SSL") {
-        connectionType = SmtpClient::ConnectionType::SslConnection;
-    } else if (selectedConnType == "TLS" || selectedConnType == "STARTTLS") {
-        connectionType = SmtpClient::ConnectionType::TlsConnection;
-    } else {
-        connectionType = SmtpClient::ConnectionType::TcpConnection;
-    }
-
-    SmtpClient smtp(smtpAddress->text(), portSpin->value(), connectionType);
-
-    smtp.setUser(username->text());
-    smtp.setPassword(password->text());
-
-    bool if_success = true;
-
-    if (!smtp.connectToHost()) {
-        QMessageBox::critical(this, tr("Fail"), tr("Fail to Connect SMTP Server"));
-        if_success = false;
-    }
-    if (if_success && !smtp.login()) {
-        QMessageBox::critical(this, tr("Fail"), tr("Fail to Login"));
-        if_success = false;
-    }
-
-    if (if_success)
-        QMessageBox::information(this, tr("Success"), tr("Succeed in connecting and login"));
-
-}
-
-void SendMailTab::slotCheckBoxSetEnableDisable(int state) {
-    if (state == Qt::Checked) {
-        smtpAddress->setEnabled(true);
-        username->setEnabled(true);
-        password->setEnabled(true);
-        portSpin->setEnabled(true);
-        connectionTypeComboBox->setEnabled(true);
-        defaultSender->setEnabled(true);
-        checkConnectionButton->setEnabled(true);
-    } else {
-        smtpAddress->setDisabled(true);
-        username->setDisabled(true);
-        password->setDisabled(true);
-        portSpin->setDisabled(true);
-        connectionTypeComboBox->setDisabled(true);
-        defaultSender->setDisabled(true);
-        checkConnectionButton->setDisabled(true);
-    }
-}
-
-AppearanceTab::AppearanceTab(QWidget *parent)
-        : QWidget(parent), appPath(qApp->applicationDirPath()),
-          settings(RESOURCE_DIR(appPath) + "/conf/gpgfrontend.ini",
-                   QSettings::IniFormat) {
-    /*****************************************
-     * Icon-Size-Box
-     *****************************************/
-    auto *iconSizeBox = new QGroupBox(tr("Iconsize"));
-    iconSizeGroup = new QButtonGroup();
-    iconSizeSmall = new QRadioButton(tr("small"));
-    iconSizeMedium = new QRadioButton(tr("medium"));
-    iconSizeLarge = new QRadioButton(tr("large"));
-
-    iconSizeGroup->addButton(iconSizeSmall, 1);
-    iconSizeGroup->addButton(iconSizeMedium, 2);
-    iconSizeGroup->addButton(iconSizeLarge, 3);
-
-    auto *iconSizeBoxLayout = new QHBoxLayout();
-    iconSizeBoxLayout->addWidget(iconSizeSmall);
-    iconSizeBoxLayout->addWidget(iconSizeMedium);
-    iconSizeBoxLayout->addWidget(iconSizeLarge);
-
-    iconSizeBox->setLayout(iconSizeBoxLayout);
-
-    /*****************************************
-     * Icon-Style-Box
-     *****************************************/
-    auto *iconStyleBox = new QGroupBox(tr("Iconstyle"));
-    iconStyleGroup = new QButtonGroup();
-    iconTextButton = new QRadioButton(tr("just text"));
-    iconIconsButton = new QRadioButton(tr("just icons"));
-    iconAllButton = new QRadioButton(tr("text and icons"));
-
-    iconStyleGroup->addButton(iconTextButton, 1);
-    iconStyleGroup->addButton(iconIconsButton, 2);
-    iconStyleGroup->addButton(iconAllButton, 3);
-
-    auto *iconStyleBoxLayout = new QHBoxLayout();
-    iconStyleBoxLayout->addWidget(iconTextButton);
-    iconStyleBoxLayout->addWidget(iconIconsButton);
-    iconStyleBoxLayout->addWidget(iconAllButton);
-
-    iconStyleBox->setLayout(iconStyleBoxLayout);
-
-    /*****************************************
-     * Window-Size-Box
-     *****************************************/
-    auto *windowSizeBox = new QGroupBox(tr("Windowstate"));
-    auto *windowSizeBoxLayout = new QHBoxLayout();
-    windowSizeCheckBox =
-            new QCheckBox(tr("Save window size and position on exit."), this);
-    windowSizeBoxLayout->addWidget(windowSizeCheckBox);
-    windowSizeBox->setLayout(windowSizeBoxLayout);
-
-    /*****************************************
-     * Info-Board-Font-Size-Box
-     *****************************************/
-
-    auto *infoBoardBox = new QGroupBox(tr("Information Board"));
-    auto *infoBoardLayout = new QHBoxLayout();
-    infoBoardFontSizeSpin = new QSpinBox();
-    infoBoardFontSizeSpin->setRange(9, 18);
-    infoBoardFontSizeSpin->setValue(10);
-    infoBoardFontSizeSpin->setSingleStep(1);
-    infoBoardLayout->addWidget(new QLabel(tr(" Front Size")));
-    infoBoardLayout->addWidget(infoBoardFontSizeSpin);
-    infoBoardBox->setLayout(infoBoardLayout);
-
-    auto *mainLayout = new QVBoxLayout;
-    mainLayout->addWidget(iconSizeBox);
-    mainLayout->addWidget(iconStyleBox);
-    mainLayout->addWidget(windowSizeBox);
-    mainLayout->addWidget(infoBoardBox);
-    mainLayout->addStretch(1);
-    setSettings();
-    setLayout(mainLayout);
-}
-
-/**********************************
- * Read the settings from config
- * and set the buttons and checkboxes
- * appropriately
- **********************************/
-void AppearanceTab::setSettings() {
-
-    // Iconsize
-    QSize iconSize = settings.value("toolbar/iconsize", QSize(24, 24)).toSize();
-    switch (iconSize.height()) {
-        case 12:
-            iconSizeSmall->setChecked(true);
-            break;
-        case 24:
-            iconSizeMedium->setChecked(true);
-            break;
-        case 32:
-            iconSizeLarge->setChecked(true);
-            break;
-    }
-    // Iconstyle
-    Qt::ToolButtonStyle iconStyle = static_cast<Qt::ToolButtonStyle>(
-            settings.value("toolbar/iconstyle", Qt::ToolButtonTextUnderIcon)
-                    .toUInt());
-    switch (iconStyle) {
-        case Qt::ToolButtonTextOnly:
-            iconTextButton->setChecked(true);
-            break;
-        case Qt::ToolButtonIconOnly:
-            iconIconsButton->setChecked(true);
-            break;
-        case Qt::ToolButtonTextUnderIcon:
-            iconAllButton->setChecked(true);
-            break;
-        default:
-            break;
-    }
-
-    // Window Save and Position
-    if (settings.value("window/windowSave").toBool())
-        windowSizeCheckBox->setCheckState(Qt::Checked);
-
-    // infoBoardFontSize
-    auto infoBoardFontSize = settings.value("informationBoard/fontSize", 10).toInt();
-    if (infoBoardFontSize < 9 || infoBoardFontSize > 18)
-        infoBoardFontSize = 10;
-    infoBoardFontSizeSpin->setValue(infoBoardFontSize);
-}
-
-/***********************************
- * get the values of the buttons and
- * write them to settings-file
- *************************************/
-void AppearanceTab::applySettings() {
-    switch (iconSizeGroup->checkedId()) {
-        case 1:
-            settings.setValue("toolbar/iconsize", QSize(12, 12));
-            break;
-        case 2:
-            settings.setValue("toolbar/iconsize", QSize(24, 24));
-            break;
-        case 3:
-            settings.setValue("toolbar/iconsize", QSize(32, 32));
-            break;
-    }
-
-    switch (iconStyleGroup->checkedId()) {
-        case 1:
-            settings.setValue("toolbar/iconstyle", Qt::ToolButtonTextOnly);
-            break;
-        case 2:
-            settings.setValue("toolbar/iconstyle", Qt::ToolButtonIconOnly);
-            break;
-        case 3:
-            settings.setValue("toolbar/iconstyle", Qt::ToolButtonTextUnderIcon);
-            break;
-    }
-
-    settings.setValue("window/windowSave", windowSizeCheckBox->isChecked());
-
-    settings.setValue("informationBoard/fontSize", infoBoardFontSizeSpin->value());
-}
-
-KeyserverTab::KeyserverTab(QWidget *parent)
-        : QWidget(parent), appPath(qApp->applicationDirPath()),
-          settings(RESOURCE_DIR(appPath) + "/conf/gpgfrontend.ini",
-                   QSettings::IniFormat) {
-
-    auto keyServerList = settings.value("keyserver/keyServerList").toStringList();
-
-    auto *mainLayout = new QVBoxLayout(this);
-
-    auto *label = new QLabel(tr("Default Key Server for import:"));
-    comboBox = new QComboBox;
-    comboBox->setEditable(false);
-    comboBox->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);
-
-    for (const auto &keyServer : keyServerList) {
-        comboBox->addItem(keyServer);
-        qDebug() << "KeyserverTab Get ListItemText" << keyServer;
-    }
-
-    comboBox->setCurrentText(
-            settings.value("keyserver/defaultKeyServer").toString());
-
-    auto *addKeyServerBox = new QWidget(this);
-    auto *addKeyServerLayout = new QHBoxLayout(addKeyServerBox);
-    auto *http = new QLabel("URL: ");
-    newKeyServerEdit = new QLineEdit(this);
-    auto *newKeyServerButton = new QPushButton(tr("Add"), this);
-    connect(newKeyServerButton, SIGNAL(clicked()), this, SLOT(addKeyServer()));
-    addKeyServerLayout->addWidget(http);
-    addKeyServerLayout->addWidget(newKeyServerEdit);
-    addKeyServerLayout->addWidget(newKeyServerButton);
-
-    mainLayout->addWidget(label);
-    mainLayout->addWidget(comboBox);
-    mainLayout->addWidget(addKeyServerBox);
-    mainLayout->addStretch(1);
-
-    // Read keylist from ini-file and fill it into combobox
-    setSettings();
-}
-
-/**********************************
- * Read the settings from config
- * and set the buttons and checkboxes
- * appropriately
- **********************************/
-void KeyserverTab::setSettings() {
-    auto *keyServerList = new QStringList();
-    for (int i = 0; i < comboBox->count(); i++) {
-        keyServerList->append(comboBox->itemText(i));
-        qDebug() << "KeyserverTab ListItemText" << comboBox->itemText(i);
-    }
-    settings.setValue("keyserver/keyServerList", *keyServerList);
-    delete keyServerList;
-    settings.setValue("keyserver/defaultKeyServer", comboBox->currentText());
-}
-
-void KeyserverTab::addKeyServer() {
-    if (newKeyServerEdit->text().startsWith("http://") ||
-        newKeyServerEdit->text().startsWith("https://")) {
-        comboBox->addItem(newKeyServerEdit->text());
-    } else {
-        comboBox->addItem("http://" + newKeyServerEdit->text());
-    }
-    comboBox->setCurrentIndex(comboBox->count() - 1);
-}
-
-/***********************************
- * get the values of the buttons and
- * write them to settings-file
- *************************************/
-void KeyserverTab::applySettings() {
-    settings.setValue("keyserver/defaultKeyServer", comboBox->currentText());
-}
-
-AdvancedTab::AdvancedTab(QWidget *parent)
-        : QWidget(parent), appPath(qApp->applicationDirPath()),
-          settings(RESOURCE_DIR(appPath) + "/conf/gpgfrontend.ini",
-                   QSettings::IniFormat) {
-    /*****************************************
-     * Steganography Box
-     *****************************************/
-    auto *steganoBox = new QGroupBox(tr("Show Steganography Options [Advanced]"));
-    auto *steganoBoxLayout = new QHBoxLayout();
-    steganoCheckBox = new QCheckBox(tr("Show Steganographic Options."), this);
-    steganoBoxLayout->addWidget(steganoCheckBox);
-    steganoBox->setLayout(steganoBoxLayout);
-
-    auto *mainLayout = new QVBoxLayout;
-    mainLayout->addWidget(steganoBox);
-    setSettings();
-    mainLayout->addStretch(1);
-    setLayout(mainLayout);
-}
-
-void AdvancedTab::setSettings() {
-    if (settings.value("advanced/steganography").toBool()) {
-        steganoCheckBox->setCheckState(Qt::Checked);
-    }
-}
-
-void AdvancedTab::applySettings() {
-    settings.setValue("advanced/steganography", steganoCheckBox->isChecked());
-}
-
 GpgPathsTab::GpgPathsTab(QWidget *parent)
         : QWidget(parent), appPath(qApp->applicationDirPath()),
           settings(RESOURCE_DIR(appPath) + "/conf/gpgfrontend.ini",
diff --git a/src/ui/main_window/MainWindowServerSlotFunction.cpp b/src/ui/main_window/MainWindowServerSlotFunction.cpp
index c9d89fac..fec60063 100644
--- a/src/ui/main_window/MainWindowServerSlotFunction.cpp
+++ b/src/ui/main_window/MainWindowServerSlotFunction.cpp
@@ -35,8 +35,7 @@
  * @return
  */
 QString MainWindow::getCryptText(const QString &shortenCryptoText) {
-    auto host = settings.value("general/currentGpgfrontendServer",
-                                  "service.gpgfrontend.pub").toString();
+
 
     QString ownKeyId = settings.value("general/ownKeyId").toString();
 
@@ -46,14 +45,16 @@ QString MainWindow::getCryptText(const QString &shortenCryptoText) {
         return {};
     }
 
+    auto utils = new ComUtils(this);
+
     QString serviceToken = settings.value("general/serviceToken").toString();
-    if (serviceToken.isEmpty()) {
+    if (serviceToken.isEmpty() || !utils->checkServiceTokenFormat(serviceToken)) {
         QMessageBox::critical(this, tr("Error"),
                               tr("Please obtain a Service Token from the server in the settings."));
         return {};
     }
 
-    QUrl reqUrl("http://127.0.0.1:9048/text/get");
+    QUrl reqUrl(utils->getUrl(ComUtils::GetFullCryptText));
     QNetworkRequest request(reqUrl);
     request.setHeader(QNetworkRequest::ContentTypeHeader, "application/json");
 
@@ -89,29 +90,63 @@ QString MainWindow::getCryptText(const QString &shortenCryptoText) {
     auto dialog = new WaitingDialog("Getting Crypt Text From Server", this);
     dialog->show();
 
-    while (reply->isRunning()) {
-        QApplication::processEvents();
-    }
+    while (reply->isRunning()) QApplication::processEvents();
 
     dialog->close();
 
     QByteArray replyData = reply->readAll().constData();
-    auto comUtils = new ComUtils(this);
-    if (comUtils->checkServerReply(replyData)) {
-        //TODO Logic
-    } else QMessageBox::critical(this, tr("Error"), tr("Unknown Error"));
+    if (utils->checkServerReply(replyData)) {
+        /**
+         * {
+         *      "cryptoText" : ...
+         *      "sha": ...
+         *      "serviceToken": ...
+         *      "date": ...
+         * }
+         */
+
+        if (!utils->checkDataValue("cryptoText")
+            || !utils->checkDataValue("sha")
+            || !utils->checkDataValue("serviceToken")) {
+            QMessageBox::critical(this, tr("Error"),
+                                  tr("The communication content with the server does not meet the requirements"));
+            return {};
+        }
+
+        auto cryptoText = utils->getDataValue("cryptoText");
+        auto sha = utils->getDataValue("sha");
+        auto serviceTokenFromServer = utils->getDataValue("serviceToken");
+
+        QCryptographicHash sha_generator(QCryptographicHash::Sha256);
+        sha_generator.addData(cryptoText.toUtf8());
+
+        if (serviceTokenFromServer == serviceToken &&
+            sha_generator.result().toHex() == sha) {
+            return cryptoText;
+        } else QMessageBox::critical(this, tr("Error"), tr("Invalid short ciphertext"));
+
+        return {};
+    }
 
     return {};
 }
 
 void MainWindow::shortenCryptText() {
 
+    // gather information
     QString serviceToken = settings.value("general/serviceToken").toString();
     QString ownKeyId = settings.value("general/ownKeyId").toString();
-
     QByteArray cryptoText = edit->curTextPage()->toPlainText().toUtf8();
 
-    QUrl reqUrl("http://127.0.0.1:9048/text/new");
+    auto utils = new ComUtils(this);
+
+    if (serviceToken.isEmpty() || !utils->checkServiceTokenFormat(serviceToken)) {
+        QMessageBox::critical(this, tr("Invalid Service Token"),
+                              tr("Please go to the setting interface to get a ServiceToken."));
+        return;
+    }
+
+    QUrl reqUrl(utils->getUrl(ComUtils::ShortenCryptText));
     QNetworkRequest request(reqUrl);
     request.setHeader(QNetworkRequest::ContentTypeHeader, "application/json");
 
@@ -166,20 +201,35 @@ void MainWindow::shortenCryptText() {
 
     QNetworkReply *reply = networkAccessManager->post(request, postData);
 
-    while (reply->isRunning()) {
-        QApplication::processEvents();
+    while (reply->isRunning()) QApplication::processEvents();
+
+    if (utils->checkServerReply(reply->readAll().constData())) {
+
+        /**
+         * {
+         *      "shortenText" : ...
+         *      "md5": ...
+         * }
+         */
+
+        if (!utils->checkDataValue("shortenText") || !utils->checkDataValue("md5")) {
+            QMessageBox::critical(this, tr("Error"),
+                                  tr("The communication content with the server does not meet the requirements"));
+            return;
+        }
+
+        QString shortenText = utils->getDataValue("shortenText");
+
+        QCryptographicHash md5_generator(QCryptographicHash::Md5);
+        md5_generator.addData(shortenText.toUtf8());
+        if (md5_generator.result().toHex() == utils->getDataValue("md5")) {
+            auto *dialog = new ShowCopyDialog(shortenText, this);
+            dialog->show();
+        } else {
+            QMessageBox::critical(this, tr("Error"), tr("There is a problem with the communication with the server"));
+            return;
+        }
     }
 
-    if (reply->error() == QNetworkReply::NoError) {
-        rapidjson::Document docReply;
-        docReply.Parse(reply->readAll().constData());
-        QString shortenText = docReply["shortenText"].GetString();
-        auto *dialog = new ShowCopyDialog(shortenText, this);
-        dialog->show();
-    } else {
-        QMessageBox::critical(this, tr("Error"), reply->errorString());
-    }
-
-
 }
 
diff --git a/src/ui/settings/SettingsAdvanced.cpp b/src/ui/settings/SettingsAdvanced.cpp
new file mode 100644
index 00000000..c49ba9ce
--- /dev/null
+++ b/src/ui/settings/SettingsAdvanced.cpp
@@ -0,0 +1,56 @@
+/**
+ * This file is part of GPGFrontend.
+ *
+ * GPGFrontend 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Foobar 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 Foobar.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The initial version of the source code is inherited from gpg4usb-team.
+ * Their source code version also complies with GNU General Public License.
+ *
+ * The source code version of this software was modified and released
+ * by Saturneric<[email protected]> starting on May 12, 2021.
+ *
+ */
+
+#include "ui/SettingsDialog.h"
+
+AdvancedTab::AdvancedTab(QWidget *parent)
+: QWidget(parent), appPath(qApp->applicationDirPath()),
+settings(RESOURCE_DIR(appPath) + "/conf/gpgfrontend.ini",
+         QSettings::IniFormat) {
+    /*****************************************
+     * Steganography Box
+     *****************************************/
+    auto *steganoBox = new QGroupBox(tr("Show Steganography Options [Advanced]"));
+    auto *steganoBoxLayout = new QHBoxLayout();
+    steganoCheckBox = new QCheckBox(tr("Show Steganographic Options."), this);
+    steganoBoxLayout->addWidget(steganoCheckBox);
+    steganoBox->setLayout(steganoBoxLayout);
+
+    auto *mainLayout = new QVBoxLayout;
+    mainLayout->addWidget(steganoBox);
+    setSettings();
+    mainLayout->addStretch(1);
+    setLayout(mainLayout);
+}
+
+void AdvancedTab::setSettings() {
+    if (settings.value("advanced/steganography").toBool()) {
+        steganoCheckBox->setCheckState(Qt::Checked);
+    }
+}
+
+void AdvancedTab::applySettings() {
+    settings.setValue("advanced/steganography", steganoCheckBox->isChecked());
+}
+
diff --git a/src/ui/settings/SettingsAppearance.cpp b/src/ui/settings/SettingsAppearance.cpp
new file mode 100644
index 00000000..aeb7ed70
--- /dev/null
+++ b/src/ui/settings/SettingsAppearance.cpp
@@ -0,0 +1,187 @@
+/**
+ * This file is part of GPGFrontend.
+ *
+ * GPGFrontend 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Foobar 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 Foobar.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The initial version of the source code is inherited from gpg4usb-team.
+ * Their source code version also complies with GNU General Public License.
+ *
+ * The source code version of this software was modified and released
+ * by Saturneric<[email protected]> starting on May 12, 2021.
+ *
+ */
+
+#include "ui/SettingsDialog.h"
+
+AppearanceTab::AppearanceTab(QWidget *parent)
+: QWidget(parent), appPath(qApp->applicationDirPath()),
+settings(RESOURCE_DIR(appPath) + "/conf/gpgfrontend.ini",
+         QSettings::IniFormat) {
+    /*****************************************
+     * Icon-Size-Box
+     *****************************************/
+    auto *iconSizeBox = new QGroupBox(tr("Iconsize"));
+    iconSizeGroup = new QButtonGroup();
+    iconSizeSmall = new QRadioButton(tr("small"));
+    iconSizeMedium = new QRadioButton(tr("medium"));
+    iconSizeLarge = new QRadioButton(tr("large"));
+
+    iconSizeGroup->addButton(iconSizeSmall, 1);
+    iconSizeGroup->addButton(iconSizeMedium, 2);
+    iconSizeGroup->addButton(iconSizeLarge, 3);
+
+    auto *iconSizeBoxLayout = new QHBoxLayout();
+    iconSizeBoxLayout->addWidget(iconSizeSmall);
+    iconSizeBoxLayout->addWidget(iconSizeMedium);
+    iconSizeBoxLayout->addWidget(iconSizeLarge);
+
+    iconSizeBox->setLayout(iconSizeBoxLayout);
+
+    /*****************************************
+     * Icon-Style-Box
+     *****************************************/
+    auto *iconStyleBox = new QGroupBox(tr("Iconstyle"));
+    iconStyleGroup = new QButtonGroup();
+    iconTextButton = new QRadioButton(tr("just text"));
+    iconIconsButton = new QRadioButton(tr("just icons"));
+    iconAllButton = new QRadioButton(tr("text and icons"));
+
+    iconStyleGroup->addButton(iconTextButton, 1);
+    iconStyleGroup->addButton(iconIconsButton, 2);
+    iconStyleGroup->addButton(iconAllButton, 3);
+
+    auto *iconStyleBoxLayout = new QHBoxLayout();
+    iconStyleBoxLayout->addWidget(iconTextButton);
+    iconStyleBoxLayout->addWidget(iconIconsButton);
+    iconStyleBoxLayout->addWidget(iconAllButton);
+
+    iconStyleBox->setLayout(iconStyleBoxLayout);
+
+    /*****************************************
+     * Window-Size-Box
+     *****************************************/
+    auto *windowSizeBox = new QGroupBox(tr("Windowstate"));
+    auto *windowSizeBoxLayout = new QHBoxLayout();
+    windowSizeCheckBox =
+            new QCheckBox(tr("Save window size and position on exit."), this);
+    windowSizeBoxLayout->addWidget(windowSizeCheckBox);
+    windowSizeBox->setLayout(windowSizeBoxLayout);
+
+    /*****************************************
+     * Info-Board-Font-Size-Box
+     *****************************************/
+
+    auto *infoBoardBox = new QGroupBox(tr("Information Board"));
+    auto *infoBoardLayout = new QHBoxLayout();
+    infoBoardFontSizeSpin = new QSpinBox();
+    infoBoardFontSizeSpin->setRange(9, 18);
+    infoBoardFontSizeSpin->setValue(10);
+    infoBoardFontSizeSpin->setSingleStep(1);
+    infoBoardLayout->addWidget(new QLabel(tr(" Front Size")));
+    infoBoardLayout->addWidget(infoBoardFontSizeSpin);
+    infoBoardBox->setLayout(infoBoardLayout);
+
+    auto *mainLayout = new QVBoxLayout;
+    mainLayout->addWidget(iconSizeBox);
+    mainLayout->addWidget(iconStyleBox);
+    mainLayout->addWidget(windowSizeBox);
+    mainLayout->addWidget(infoBoardBox);
+    mainLayout->addStretch(1);
+    setSettings();
+    setLayout(mainLayout);
+}
+
+/**********************************
+ * Read the settings from config
+ * and set the buttons and checkboxes
+ * appropriately
+ **********************************/
+void AppearanceTab::setSettings() {
+
+    // Iconsize
+    QSize iconSize = settings.value("toolbar/iconsize", QSize(24, 24)).toSize();
+    switch (iconSize.height()) {
+        case 12:
+            iconSizeSmall->setChecked(true);
+            break;
+            case 24:
+                iconSizeMedium->setChecked(true);
+                break;
+                case 32:
+                    iconSizeLarge->setChecked(true);
+                    break;
+    }
+    // Iconstyle
+    Qt::ToolButtonStyle iconStyle = static_cast<Qt::ToolButtonStyle>(
+            settings.value("toolbar/iconstyle", Qt::ToolButtonTextUnderIcon)
+            .toUInt());
+    switch (iconStyle) {
+        case Qt::ToolButtonTextOnly:
+            iconTextButton->setChecked(true);
+            break;
+            case Qt::ToolButtonIconOnly:
+                iconIconsButton->setChecked(true);
+                break;
+                case Qt::ToolButtonTextUnderIcon:
+                    iconAllButton->setChecked(true);
+                    break;
+                    default:
+                        break;
+    }
+
+    // Window Save and Position
+    if (settings.value("window/windowSave").toBool())
+        windowSizeCheckBox->setCheckState(Qt::Checked);
+
+    // infoBoardFontSize
+    auto infoBoardFontSize = settings.value("informationBoard/fontSize", 10).toInt();
+    if (infoBoardFontSize < 9 || infoBoardFontSize > 18)
+        infoBoardFontSize = 10;
+    infoBoardFontSizeSpin->setValue(infoBoardFontSize);
+}
+
+/***********************************
+ * get the values of the buttons and
+ * write them to settings-file
+ *************************************/
+void AppearanceTab::applySettings() {
+    switch (iconSizeGroup->checkedId()) {
+        case 1:
+            settings.setValue("toolbar/iconsize", QSize(12, 12));
+            break;
+            case 2:
+                settings.setValue("toolbar/iconsize", QSize(24, 24));
+                break;
+                case 3:
+                    settings.setValue("toolbar/iconsize", QSize(32, 32));
+                    break;
+    }
+
+    switch (iconStyleGroup->checkedId()) {
+        case 1:
+            settings.setValue("toolbar/iconstyle", Qt::ToolButtonTextOnly);
+            break;
+            case 2:
+                settings.setValue("toolbar/iconstyle", Qt::ToolButtonIconOnly);
+                break;
+                case 3:
+                    settings.setValue("toolbar/iconstyle", Qt::ToolButtonTextUnderIcon);
+                    break;
+    }
+
+    settings.setValue("window/windowSave", windowSizeCheckBox->isChecked());
+
+    settings.setValue("informationBoard/fontSize", infoBoardFontSizeSpin->value());
+}
+
diff --git a/src/ui/settings/SettingsGeneral.cpp b/src/ui/settings/SettingsGeneral.cpp
new file mode 100644
index 00000000..ede15182
--- /dev/null
+++ b/src/ui/settings/SettingsGeneral.cpp
@@ -0,0 +1,314 @@
+/**
+ * This file is part of GPGFrontend.
+ *
+ * GPGFrontend 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Foobar 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 Foobar.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The initial version of the source code is inherited from gpg4usb-team.
+ * Their source code version also complies with GNU General Public License.
+ *
+ * The source code version of this software was modified and released
+ * by Saturneric<[email protected]> starting on May 12, 2021.
+ *
+ */
+
+#include "ui/SettingsDialog.h"
+#include "ui/WaitingDialog.h"
+
+#include "server/ComUtils.h"
+
+#include "rapidjson/document.h"
+#include "rapidjson/prettywriter.h"
+
+GeneralTab::GeneralTab(GpgME::GpgContext *ctx, QWidget *parent)
+        : QWidget(parent), appPath(qApp->applicationDirPath()),
+          settings(RESOURCE_DIR(appPath) + "/conf/gpgfrontend.ini",
+                   QSettings::IniFormat) {
+    mCtx = ctx;
+
+    /*****************************************
+     * GpgFrontend Server
+     *****************************************/
+    auto *serverBox = new QGroupBox(tr("GpgFrontend Server"));
+    auto *serverBoxLayout = new QVBoxLayout();
+    serverSelectBox = new QComboBox();
+    serverBoxLayout->addWidget(serverSelectBox);
+    serverBoxLayout->addWidget(new QLabel(
+            tr("Server that provides short key and key exchange services")));
+    serverBox->setLayout(serverBoxLayout);
+
+    /*****************************************
+     * Save-Checked-Keys-Box
+     *****************************************/
+    auto *saveCheckedKeysBox = new QGroupBox(tr("Save Checked Keys"));
+    auto *saveCheckedKeysBoxLayout = new QHBoxLayout();
+    saveCheckedKeysCheckBox = new QCheckBox(
+            tr("Save checked private keys on exit and restore them on next start."),
+            this);
+    saveCheckedKeysBoxLayout->addWidget(saveCheckedKeysCheckBox);
+    saveCheckedKeysBox->setLayout(saveCheckedKeysBoxLayout);
+
+    /*****************************************
+     * Key-Impport-Confirmation Box
+     *****************************************/
+    auto *importConfirmationBox =
+            new QGroupBox(tr("Confirm drag'n'drop key import"));
+    auto *importConfirmationBoxLayout = new QHBoxLayout();
+    importConfirmationCheckBox = new QCheckBox(
+            tr("Import files dropped on the keylist without confirmation."), this);
+    importConfirmationBoxLayout->addWidget(importConfirmationCheckBox);
+    importConfirmationBox->setLayout(importConfirmationBoxLayout);
+
+    /*****************************************
+     * Language Select Box
+     *****************************************/
+    auto *langBox = new QGroupBox(tr("Language"));
+    auto *langBoxLayout = new QVBoxLayout();
+    langSelectBox = new QComboBox;
+    lang = SettingsDialog::listLanguages();
+
+    for (const auto &l: lang) { langSelectBox->addItem(l); }
+
+    langBoxLayout->addWidget(langSelectBox);
+    langBoxLayout->addWidget(
+            new QLabel(tr("<b>NOTE: </b> GpgFrontend will restart automatically if "
+                          "you change the language!")));
+    langBox->setLayout(langBoxLayout);
+    connect(langSelectBox, SIGNAL(currentIndexChanged(int)), this,
+            SLOT(slotLanguageChanged()));
+
+    /*****************************************
+     * Own Key Select Box
+     *****************************************/
+    auto *ownKeyBox = new QGroupBox(tr("Own key"));
+    auto *ownKeyBoxLayout = new QVBoxLayout();
+    auto *ownKeyServiceTokenLayout = new QHBoxLayout();
+    ownKeySelectBox = new QComboBox;
+    getServiceTokenButton = new QPushButton(tr("Get Service Token"));
+    serviceTokenLabel = new QLabel(tr("No Service Token Found"));
+
+    ownKeyBox->setLayout(ownKeyBoxLayout);
+    mKeyList = new KeyList(mCtx);
+
+    // Fill the keyid hashmap
+    keyIds.insert("", tr("<none>"));
+
+    for (const auto &keyid : *mKeyList->getAllPrivateKeys()) {
+        auto &key = mCtx->getKeyById(keyid);
+        keyIds.insert(key.id, key.uids.first().uid);
+    }
+    for (const auto &k : keyIds.keys()) {
+        ownKeySelectBox->addItem(keyIds.find(k).value());
+        keyIdsList.append(k);
+    }
+    connect(ownKeySelectBox, SIGNAL(currentIndexChanged(int)), this,
+            SLOT(slotOwnKeyIdChanged()));
+    connect(getServiceTokenButton, SIGNAL(clicked(bool)), this,
+            SLOT(slotGetServiceToken()));
+
+    ownKeyBoxLayout->addWidget(new QLabel(
+            tr("Key pair for synchronization and identity authentication")));
+    ownKeyBoxLayout->addWidget(ownKeySelectBox);
+    ownKeyBoxLayout->addLayout(ownKeyServiceTokenLayout);
+    ownKeyServiceTokenLayout->addWidget(getServiceTokenButton);
+    ownKeyServiceTokenLayout->addWidget(serviceTokenLabel);
+    ownKeyServiceTokenLayout->stretch(0);
+
+    /*****************************************
+     * Mainlayout
+     *****************************************/
+    auto *mainLayout = new QVBoxLayout;
+    mainLayout->addWidget(serverBox);
+    mainLayout->addWidget(saveCheckedKeysBox);
+    mainLayout->addWidget(importConfirmationBox);
+    mainLayout->addWidget(langBox);
+    mainLayout->addWidget(ownKeyBox);
+
+    setSettings();
+    mainLayout->addStretch(1);
+    setLayout(mainLayout);
+}
+
+/**********************************
+ * Read the settings from config
+ * and set the buttons and checkboxes
+ * appropriately
+ **********************************/
+void GeneralTab::setSettings() {
+    // Keysaving
+    if (settings.value("keys/saveKeyChecked").toBool()) {
+        saveCheckedKeysCheckBox->setCheckState(Qt::Checked);
+    }
+
+    auto serverList = settings.value("general/gpgfrontendServerList").toStringList();
+    if (serverList.empty()) {
+        serverList.append("service.gpgfrontend.pub");
+        serverList.append("localhost");
+    }
+    for (const auto &s : serverList)
+        serverSelectBox->addItem(s);
+    serverSelectBox->setCurrentText(settings.value("general/currentGpgfrontendServer",
+                                                   "service.gpgfrontend.pub").toString());
+
+    // Language setting
+    QString langKey = settings.value("int/lang").toString();
+    QString langValue = lang.value(langKey);
+    if (langKey != "") {
+        langSelectBox->setCurrentIndex(langSelectBox->findText(langValue));
+    }
+
+    QString own_key_id = settings.value("general/ownKeyId").toString();
+    qDebug() << "OwnKeyId" << own_key_id;
+    if (own_key_id.isEmpty()) {
+        ownKeySelectBox->setCurrentText("<none>");
+    } else {
+        const auto text = keyIds.find(own_key_id).value();
+        qDebug() << "OwnKey" << own_key_id << text;
+        ownKeySelectBox->setCurrentText(text);
+    }
+
+    serviceToken = settings.value("general/serviceToken").toString();
+    qDebug() << "Load Service Token" << serviceToken;
+    if (!serviceToken.isEmpty()) {
+        serviceTokenLabel->setText(serviceToken);
+    }
+
+    // Get own key information from keydb/gpg.conf (if contained)
+    if (settings.value("general/confirmImportKeys", Qt::Checked).toBool()) {
+        importConfirmationCheckBox->setCheckState(Qt::Checked);
+    }
+}
+
+/***********************************
+ * get the values of the buttons and
+ * write them to settings-file
+ *************************************/
+void GeneralTab::applySettings() {
+    settings.setValue("keys/saveKeyChecked",
+                      saveCheckedKeysCheckBox->isChecked());
+
+    settings.setValue("general/currentGpgfrontendServer",
+                      serverSelectBox->currentText());
+
+    auto *serverList = new QStringList();
+    for (int i = 0; i < serverSelectBox->count(); i++)
+        serverList->append(serverSelectBox->itemText(i));
+    settings.setValue("general/gpgfrontendServerList",
+                      *serverList);
+    delete serverList;
+
+    settings.setValue("int/lang", lang.key(langSelectBox->currentText()));
+
+    settings.setValue("general/ownKeyId",
+                      keyIdsList[ownKeySelectBox->currentIndex()]);
+
+    settings.setValue("general/serviceToken",
+                      serviceToken);
+
+    settings.setValue("general/confirmImportKeys",
+                      importConfirmationCheckBox->isChecked());
+}
+
+void GeneralTab::slotLanguageChanged() { emit signalRestartNeeded(true); }
+
+void GeneralTab::slotOwnKeyIdChanged() {
+    // Set ownKeyId to currently selected
+    this->serviceTokenLabel->setText(tr("No Service Token Found"));
+    serviceToken.clear();
+}
+
+void GeneralTab::slotGetServiceToken() {
+
+    auto utils = new ComUtils(this);
+
+    QUrl reqUrl(utils->getUrl(ComUtils::GetServiceToken));
+    QNetworkRequest request(reqUrl);
+    request.setHeader(QNetworkRequest::ContentTypeHeader, "application/json");
+
+    // Building Post Data
+    QByteArray keyDataBuf;
+
+    const auto keyId = keyIdsList[ownKeySelectBox->currentIndex()];
+
+    qDebug() << "KeyId" << keyIdsList[ownKeySelectBox->currentIndex()];
+
+    if (keyId.isEmpty()) {
+        QMessageBox::critical(this, tr("Invalid Operation"),
+                              tr("Own Key can not be None while getting service token."));
+        return;
+    }
+
+    QStringList selectedKeyIds(keyIdsList[ownKeySelectBox->currentIndex()]);
+    mCtx->exportKeys(&selectedKeyIds, &keyDataBuf);
+
+    qDebug() << "keyDataBuf" << keyDataBuf;
+
+    rapidjson::Value p, v;
+
+    rapidjson::Document doc;
+    doc.SetObject();
+
+    p.SetString(keyDataBuf.constData(), keyDataBuf.count());
+
+    auto version = qApp->applicationVersion();
+    v.SetString(version.toUtf8().constData(), qApp->applicationVersion().count());
+
+    doc.AddMember("publicKey", p, doc.GetAllocator());
+    doc.AddMember("version", v, doc.GetAllocator());
+
+    rapidjson::StringBuffer sb;
+    rapidjson::PrettyWriter<rapidjson::StringBuffer> writer(sb);
+    doc.Accept(writer);
+
+    QByteArray postData(sb.GetString());
+
+    QNetworkReply *reply = manager.post(request, postData);
+
+    auto dialog = new WaitingDialog("Getting Token From Server", this);
+    dialog->show();
+
+    while (reply->isRunning()) {
+        QApplication::processEvents();
+    }
+
+    dialog->close();
+
+    if (utils->checkServerReply(reply->readAll().constData())) {
+
+        /**
+         * {
+         *      "serviceToken" : ...
+         *      "fpr": ...
+         * }
+         */
+
+        if(!utils->checkDataValue("serviceToken") || !utils->checkDataValue("fpr")) {
+            QMessageBox::critical(this, tr("Error"), tr("The communication content with the server does not meet the requirements"));
+            return;
+        }
+
+        QString serviceTokenTemp = utils->getDataValue("serviceToken");
+        QString fpr = utils->getDataValue("fpr");
+        auto key = mCtx->getKeyByFpr(fpr);
+        if (utils->checkServiceTokenFormat(serviceTokenTemp) && key.good) {
+            serviceToken = serviceTokenTemp;
+            qDebug() << "Get Service Token" << serviceToken;
+            // Auto update settings
+            settings.setValue("general/serviceToken", serviceToken);
+            serviceTokenLabel->setText(serviceToken);
+        } else {
+            QMessageBox::critical(this, tr("Error"), tr("There is a problem with the communication with the server"));
+        }
+    }
+
+}
diff --git a/src/ui/settings/SettingsKeyServer.cpp b/src/ui/settings/SettingsKeyServer.cpp
new file mode 100644
index 00000000..ade33a46
--- /dev/null
+++ b/src/ui/settings/SettingsKeyServer.cpp
@@ -0,0 +1,100 @@
+/**
+ * This file is part of GPGFrontend.
+ *
+ * GPGFrontend 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Foobar 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 Foobar.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The initial version of the source code is inherited from gpg4usb-team.
+ * Their source code version also complies with GNU General Public License.
+ *
+ * The source code version of this software was modified and released
+ * by Saturneric<[email protected]> starting on May 12, 2021.
+ *
+ */
+
+#include "ui/SettingsDialog.h"
+
+KeyserverTab::KeyserverTab(QWidget *parent)
+: QWidget(parent), appPath(qApp->applicationDirPath()),
+settings(RESOURCE_DIR(appPath) + "/conf/gpgfrontend.ini",
+         QSettings::IniFormat) {
+
+    auto keyServerList = settings.value("keyserver/keyServerList").toStringList();
+
+    auto *mainLayout = new QVBoxLayout(this);
+
+    auto *label = new QLabel(tr("Default Key Server for import:"));
+    comboBox = new QComboBox;
+    comboBox->setEditable(false);
+    comboBox->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);
+
+    for (const auto &keyServer : keyServerList) {
+        comboBox->addItem(keyServer);
+        qDebug() << "KeyserverTab Get ListItemText" << keyServer;
+    }
+
+    comboBox->setCurrentText(
+            settings.value("keyserver/defaultKeyServer").toString());
+
+    auto *addKeyServerBox = new QWidget(this);
+    auto *addKeyServerLayout = new QHBoxLayout(addKeyServerBox);
+    auto *http = new QLabel("URL: ");
+    newKeyServerEdit = new QLineEdit(this);
+    auto *newKeyServerButton = new QPushButton(tr("Add"), this);
+    connect(newKeyServerButton, SIGNAL(clicked()), this, SLOT(addKeyServer()));
+    addKeyServerLayout->addWidget(http);
+    addKeyServerLayout->addWidget(newKeyServerEdit);
+    addKeyServerLayout->addWidget(newKeyServerButton);
+
+    mainLayout->addWidget(label);
+    mainLayout->addWidget(comboBox);
+    mainLayout->addWidget(addKeyServerBox);
+    mainLayout->addStretch(1);
+
+    // Read keylist from ini-file and fill it into combobox
+    setSettings();
+}
+
+/**********************************
+ * Read the settings from config
+ * and set the buttons and checkboxes
+ * appropriately
+ **********************************/
+void KeyserverTab::setSettings() {
+    auto *keyServerList = new QStringList();
+    for (int i = 0; i < comboBox->count(); i++) {
+        keyServerList->append(comboBox->itemText(i));
+        qDebug() << "KeyserverTab ListItemText" << comboBox->itemText(i);
+    }
+    settings.setValue("keyserver/keyServerList", *keyServerList);
+    delete keyServerList;
+    settings.setValue("keyserver/defaultKeyServer", comboBox->currentText());
+}
+
+void KeyserverTab::addKeyServer() {
+    if (newKeyServerEdit->text().startsWith("http://") ||
+    newKeyServerEdit->text().startsWith("https://")) {
+        comboBox->addItem(newKeyServerEdit->text());
+    } else {
+        comboBox->addItem("http://" + newKeyServerEdit->text());
+    }
+    comboBox->setCurrentIndex(comboBox->count() - 1);
+}
+
+/***********************************
+ * get the values of the buttons and
+ * write them to settings-file
+ *************************************/
+void KeyserverTab::applySettings() {
+    settings.setValue("keyserver/defaultKeyServer", comboBox->currentText());
+}
diff --git a/src/ui/settings/SettingsSendMail.cpp b/src/ui/settings/SettingsSendMail.cpp
new file mode 100644
index 00000000..4c80dc89
--- /dev/null
+++ b/src/ui/settings/SettingsSendMail.cpp
@@ -0,0 +1,175 @@
+/**
+ * This file is part of GPGFrontend.
+ *
+ * GPGFrontend 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Foobar 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 Foobar.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * The initial version of the source code is inherited from gpg4usb-team.
+ * Their source code version also complies with GNU General Public License.
+ *
+ * The source code version of this software was modified and released
+ * by Saturneric<[email protected]> starting on May 12, 2021.
+ *
+ */
+
+#include "ui/SettingsDialog.h"
+#include "smtp/SmtpMime"
+
+SendMailTab::SendMailTab(QWidget *parent)
+        : QWidget(parent), appPath(qApp->applicationDirPath()),
+          settings(RESOURCE_DIR(appPath) + "/conf/gpgfrontend.ini",
+                   QSettings::IniFormat) {
+
+    enableCheckBox = new QCheckBox(tr("Enable"));
+    enableCheckBox->setTristate(false);
+
+    smtpAddress = new QLineEdit();
+    username = new QLineEdit();
+    password = new QLineEdit();
+    password->setEchoMode(QLineEdit::Password);
+
+    portSpin = new QSpinBox();
+    portSpin->setMinimum(1);
+    portSpin->setMaximum(65535);
+    connectionTypeComboBox = new QComboBox();
+    connectionTypeComboBox->addItem("None");
+    connectionTypeComboBox->addItem("SSL");
+    connectionTypeComboBox->addItem("TLS");
+    connectionTypeComboBox->addItem("STARTTLS");
+
+    defaultSender = new QLineEdit();;
+    checkConnectionButton = new QPushButton(tr("Check Connection"));
+
+    auto layout = new QGridLayout();
+    layout->addWidget(enableCheckBox, 0, 0);
+    layout->addWidget(new QLabel(tr("SMTP Address")), 1, 0);
+    layout->addWidget(smtpAddress, 1, 1, 1, 4);
+    layout->addWidget(new QLabel(tr("Username")), 2, 0);
+    layout->addWidget(username, 2, 1, 1, 4);
+    layout->addWidget(new QLabel(tr("Password")), 3, 0);
+    layout->addWidget(password, 3, 1, 1, 4);
+    layout->addWidget(new QLabel(tr("Port")), 4, 0);
+    layout->addWidget(portSpin, 4, 1, 1, 1);
+    layout->addWidget(new QLabel(tr("Connection Security")), 5, 0);
+    layout->addWidget(connectionTypeComboBox, 5, 1, 1, 1);
+
+    layout->addWidget(new QLabel(tr("Default Sender")), 6, 0);
+    layout->addWidget(defaultSender, 6, 1, 1, 4);
+    layout->addWidget(checkConnectionButton, 7, 0);
+
+    connect(enableCheckBox, SIGNAL(stateChanged(int)), this, SLOT(slotCheckBoxSetEnableDisable(int)));
+    connect(checkConnectionButton, SIGNAL(clicked(bool)), this, SLOT(slotCheckConnection()));
+
+
+    this->setLayout(layout);
+    setSettings();
+}
+
+/**********************************
+ * Read the settings from config
+ * and set the buttons and checkboxes
+ * appropriately
+ **********************************/
+void SendMailTab::setSettings() {
+
+    if (settings.value("sendMail/enable", false).toBool())
+        enableCheckBox->setCheckState(Qt::Checked);
+    else {
+        enableCheckBox->setCheckState(Qt::Unchecked);
+        smtpAddress->setDisabled(true);
+        username->setDisabled(true);
+        password->setDisabled(true);
+        portSpin->setDisabled(true);
+        connectionTypeComboBox->setDisabled(true);
+        defaultSender->setDisabled(true);
+        checkConnectionButton->setDisabled(true);
+    }
+
+    smtpAddress->setText(settings.value("sendMail/smtpAddress", QString()).toString());
+    username->setText(settings.value("sendMail/username", QString()).toString());
+    password->setText(settings.value("sendMail/password", QString()).toString());
+    portSpin->setValue(settings.value("sendMail/port", 25).toInt());
+    connectionTypeComboBox->setCurrentText(settings.value("sendMail/connectionType", "None").toString());
+    defaultSender->setText(settings.value("sendMail/defaultSender", QString()).toString());
+
+}
+
+/***********************************
+ * get the values of the buttons and
+ * write them to settings-file
+ *************************************/
+void SendMailTab::applySettings() {
+
+    settings.setValue("sendMail/smtpAddress", smtpAddress->text());
+    settings.setValue("sendMail/username", username->text());
+    settings.setValue("sendMail/password", password->text());
+    settings.setValue("sendMail/port", portSpin->value());
+    settings.setValue("sendMail/connectionType", connectionTypeComboBox->currentText());
+    settings.setValue("sendMail/defaultSender", defaultSender->text());
+
+    settings.setValue("sendMail/enable", enableCheckBox->isChecked());
+}
+
+void SendMailTab::slotCheckConnection() {
+
+    SmtpClient::ConnectionType connectionType;
+    const auto selectedConnType = connectionTypeComboBox->currentText();
+    if (selectedConnType == "SSL") {
+        connectionType = SmtpClient::ConnectionType::SslConnection;
+    } else if (selectedConnType == "TLS" || selectedConnType == "STARTTLS") {
+        connectionType = SmtpClient::ConnectionType::TlsConnection;
+    } else {
+        connectionType = SmtpClient::ConnectionType::TcpConnection;
+    }
+
+    SmtpClient smtp(smtpAddress->text(), portSpin->value(), connectionType);
+
+    smtp.setUser(username->text());
+    smtp.setPassword(password->text());
+
+    bool if_success = true;
+
+    if (!smtp.connectToHost()) {
+        QMessageBox::critical(this, tr("Fail"), tr("Fail to Connect SMTP Server"));
+        if_success = false;
+    }
+    if (if_success && !smtp.login()) {
+        QMessageBox::critical(this, tr("Fail"), tr("Fail to Login"));
+        if_success = false;
+    }
+
+    if (if_success)
+        QMessageBox::information(this, tr("Success"), tr("Succeed in connecting and login"));
+
+}
+
+void SendMailTab::slotCheckBoxSetEnableDisable(int state) {
+    if (state == Qt::Checked) {
+        smtpAddress->setEnabled(true);
+        username->setEnabled(true);
+        password->setEnabled(true);
+        portSpin->setEnabled(true);
+        connectionTypeComboBox->setEnabled(true);
+        defaultSender->setEnabled(true);
+        checkConnectionButton->setEnabled(true);
+    } else {
+        smtpAddress->setDisabled(true);
+        username->setDisabled(true);
+        password->setDisabled(true);
+        portSpin->setDisabled(true);
+        connectionTypeComboBox->setDisabled(true);
+        defaultSender->setDisabled(true);
+        checkConnectionButton->setDisabled(true);
+    }
+}
+