refactor: Mainwindow, adjust how and where the ip address is shown.

- Add a new method updateNetworkInfo to update lblIpAddresses
   This method can be hooked to the system network info in the future
   when we want to have this be more dynamic.
 - Only show the IP address when in server mode.
 - When showing the IP address show either the suggested IP or a message the user maybe offline
 - Use the linkVisited color to for our error message

src/lib/gui/MainWindow.cpp

@@ -220,7 +220,8 @@ void MainWindow::setupControls()
   secureSocket(false);
 
   ui->btnConfigureServer->setIcon(QIcon::fromTheme(QStringLiteral("configure")));
-  ui->lblIpAddresses->setText(tr("This computer's IP addresses: %1").arg(getIPAddresses()));
+
+  updateNetworkInfo();
 
   if (Settings::value(Settings::Core::LastVersion).toString() != kVersion) {
     Settings::setValue(Settings::Core::LastVersion, kVersion);
@@ -567,6 +568,7 @@ void MainWindow::coreModeToggled()
 
 void MainWindow::updateModeControls(bool serverMode)
 {
+  ui->lblIpAddresses->setVisible(serverMode);
   ui->serverOptions->setVisible(serverMode);
   ui->clientOptions->setVisible(!serverMode);
   ui->lblNoMode->setVisible(false);
@@ -606,6 +608,48 @@ void MainWindow::updateSecurityIcon(bool visible)
   m_lblSecurityStatus->setPixmap(icon.pixmap(QSize(32, 32)));
 }
 
+void MainWindow::updateNetworkInfo()
+{
+  static const auto colorText = QStringLiteral(R"(<span style="color:%1;">%2</span>)");
+
+  QStringList ipList;
+  QString suggestedAddress;
+
+  bool hinted = false;
+
+  const auto addresses = QNetworkInterface::allAddresses();
+  for (const auto &address : addresses) {
+    if (address.protocol() == QAbstractSocket::IPv4Protocol && address != QHostAddress(QHostAddress::LocalHost) &&
+        !address.isInSubnet(QHostAddress::parseSubnet("169.254.0.0/16"))) {
+      // usually 192.168.x.x is a useful ip for the user, so indicate
+      // this by coloring it in the "link" color
+      if (!hinted && address.isInSubnet(QHostAddress::parseSubnet("192.168/16"))) {
+        suggestedAddress = address.toString();
+        ipList.append(colorText.arg(palette().link().color().name(), suggestedAddress));
+        hinted = true;
+      } else {
+        ipList.append(address.toString());
+      }
+    }
+  }
+
+  if (ipList.isEmpty()) {
+    ui->lblIpAddresses->setText(colorText.arg(palette().linkVisited().color().name(), tr("No IP Detected")));
+    ui->lblIpAddresses->setToolTip(tr("Unable to detect an IP address. Check your network connection is active."));
+    return;
+  }
+
+  ui->lblIpAddresses->setText(
+      QStringLiteral("Suggested IP: %1").arg(suggestedAddress.isEmpty() ? ipList.first() : suggestedAddress)
+  );
+
+  if (auto toolTipBase = tr("<p>If connecting via the hostname fails, try %1</p>"); ipList.count() < 2) {
+    ui->lblIpAddresses->setToolTip(toolTipBase.arg(tr("the suggested IP.")));
+  } else {
+    ui->lblIpAddresses->setToolTip(toolTipBase.arg(tr("one of the following IPs:<br/>%1").arg(ipList.join("br/>"))));
+  }
+}
+
 void MainWindow::serverConnectionConfigureClient(const QString &clientName)
 {
   Settings::setValue(Settings::Server::ConfigVisible, true);
@@ -996,36 +1040,6 @@ void MainWindow::coreConnectionStateChanged(CoreConnectionState state)
   }
 }
 
-QString MainWindow::getIPAddresses() const
-{
-  QStringList result;
-  bool hinted = false;
-  const auto localnet = QHostAddress::parseSubnet("192.168.0.0/16");
-  const QList<QHostAddress> addresses = QNetworkInterface::allAddresses();
-
-  for (const auto &address : addresses) {
-    if (address.protocol() == QAbstractSocket::IPv4Protocol && address != QHostAddress(QHostAddress::LocalHost) &&
-        !address.isInSubnet(QHostAddress::parseSubnet("169.254.0.0/16"))) {
-
-      // usually 192.168.x.x is a useful ip for the user, so indicate
-      // this by coloring it in the "link" color.
-      if (!hinted && address.isInSubnet(localnet)) {
-        QString format = R"(<span style="color:%1;">%2</span>)";
-        result.append(format.arg(palette().link().color().name(), address.toString()));
-        hinted = true;
-      } else {
-        result.append(address.toString());
-      }
-    }
-  }
-
-  if (result.isEmpty()) {
-    result.append("Unknown");
-  }
-
-  return result.join(", ");
-}
-
 void MainWindow::updateLocalFingerprint()
 {
   const bool tlsEnabled = Settings::value(Settings::Security::TlsEnabled).toBool();

src/lib/gui/MainWindow.h

@@ -113,6 +113,7 @@ private:
 
   void showMyFingerprint();
   void updateSecurityIcon(bool visible);
+  void updateNetworkInfo();
 
   void coreModeToggled();
   void updateModeControls(bool serverMode);
@@ -126,7 +127,6 @@ private:
   void setIcon();
   void setStatus(const QString &status);
   void updateFromLogLine(const QString &line);
-  [[nodiscard]] QString getIPAddresses() const;
   void checkConnected(const QString &line);
   void checkFingerprint(const QString &line);
   [[nodiscard]] QString getTimeStamp() const;

src/lib/gui/MainWindow.ui

@@ -6,8 +6,8 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>735</width>
-    <height>515</height>
+    <width>781</width>
+    <height>483</height>
    </rect>
   </property>
   <property name="sizePolicy">
@@ -131,31 +131,25 @@
          </property>
          <property name="sizeHint" stdset="0">
           <size>
-           <width>40</width>
+           <width>6</width>
            <height>20</height>
           </size>
          </property>
         </spacer>
        </item>
+       <item>
+        <widget class="QLabel" name="lblIpAddresses">
+         <property name="sizePolicy">
+          <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
+           <horstretch>0</horstretch>
+           <verstretch>0</verstretch>
+          </sizepolicy>
+         </property>
+        </widget>
+       </item>
       </layout>
      </widget>
     </item>
-    <item>
-     <widget class="QLabel" name="lblIpAddresses">
-      <property name="sizePolicy">
-       <sizepolicy hsizetype="Preferred" vsizetype="Fixed">
-        <horstretch>0</horstretch>
-        <verstretch>0</verstretch>
-       </sizepolicy>
-      </property>
-      <property name="toolTip">
-       <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;The highlighted IP is the one we think you should use. The server listens on all IPs, so the other IPs may work as well.&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
-      </property>
-      <property name="text">
-       <string notr="true">This computer's IP addresses:</string>
-      </property>
-     </widget>
-    </item>
     <item>
      <widget class="QGroupBox" name="groupBox">
       <property name="sizePolicy">