Show view for web registration if out-of-band URL is provided

data/servers.json

@@ -42,6 +42,7 @@
 	{
 		"jid": "dismail.de",
 		"supportsInBandRegistration": false,
+		"registrationWebPage": "https://dismail.de/register.html",
 		"hosting": "professional",
 		"passwordReset": false,
 		"mucSupport": true,

src/Kaidan.h

@@ -217,6 +217,14 @@ signals:
 	 */
 	void registrationFormReceived(DataFormModel *dataFormModel);
 
+	/**
+	 * Emitted when an out-of-band URL for registration is received from the
+	 * server.
+	 *
+	 * @param outOfBandUrl URL used for out-of-band registration
+	 */
+	void registrationOutOfBandUrlReceived(const QString &outOfBandUrl);
+
 	/**
 	 * Emitted to request a registration form from the server which is set as the
 	 * currently used JID.

src/RegistrationManager.cpp

@@ -121,8 +121,27 @@ void RegistrationManager::handleRegistrationFormReceived(const QXmppRegisterIq &
 	bool isFakeForm;
 	QXmppDataForm newDataForm = extractFormFromRegisterIq(iq, isFakeForm);
 
-	// If the data form is not set, there is a problem with the server.
+	// If there is no registration data form, try to use an out-of-band URL.
 	if (newDataForm.fields().isEmpty()) {
+#if QXMPP_VERSION >= QT_VERSION_CHECK(1, 5, 0)
+		// If there is a standardized out-of-band URL, use that.
+		if (!iq.outOfBandUrl().isEmpty()) {
+			emit Kaidan::instance()->registrationOutOfBandUrlReceived(iq.outOfBandUrl());
+			return;
+		}
+#endif
+		// Try to find an out-of-band URL within the instructions element.
+		// Most servers include a text with a link to the website.
+		const auto words = iq.instructions().split(u' ');
+		for (const auto &instructionPart : words) {
+			if (instructionPart.startsWith(u"https://")) {
+				emit Kaidan::instance()->registrationOutOfBandUrlReceived(instructionPart);
+				return;
+			}
+		}
+
+		// If no URL has been found in the instructions, there is a
+		// problem with the server.
 		emit m_clientWorker->connectionErrorChanged(ClientWorker::RegistrationUnsupported);
 		return;
 	}

src/qml/registration/AutomaticRegistrationPage.qml

@@ -102,6 +102,10 @@ RegistrationPage {
 				removeLoadingView()
 		}
 
+		function onRegistrationOutOfBandUrlReceived(outOfBandUrl) {
+			requestRegistrationFormFromAnotherServer(qsTr("The server does currently not support registration via this app."))
+		}
+
 		function onRegistrationFailed(error, errorMessage) {
 			switch (error) {
 			case RegistrationManager.InBandRegistrationNotSupported:

src/qml/registration/ManualRegistrationPage.qml

@@ -120,10 +120,6 @@ RegistrationPage {
 			jumpToPreviousView()
 			removeLoadingView()
 		}
-	}
-
-	Connections {
-		target: Kaidan
 
 		function onRegistrationFormReceived(dataFormModel) {
 			formModel = dataFormModel
@@ -175,6 +171,11 @@ RegistrationPage {
 			focusFieldViews()
 		}
 
+		function onRegistrationOutOfBandUrlReceived(outOfBandUrl) {
+			serverView.outOfBandUrl = outOfBandUrl
+			handleInBandRegistrationNotSupported()
+		}
+
 		// Depending on the error, the swipe view jumps to the view where the input should be corrected.
 		// For all remaining errors, the swipe view jumps to the server view.
 		function onRegistrationFailed(error, errorMessage) {
@@ -182,7 +183,7 @@ RegistrationPage {
 
 			switch(error) {
 			case RegistrationManager.InBandRegistrationNotSupported:
-				handleInBandRegistrationNotSupportedError()
+				handleInBandRegistrationNotSupported()
 				break
 			case RegistrationManager.UsernameConflict:
 				requestRegistrationForm()
@@ -229,14 +230,14 @@ RegistrationPage {
 	}
 
 	/**
-	 * Shows a passive notification if the server does not support In-Band Registration.
+	 * Shows a passive notification regarding the missing support of In-Band Registration.
 	 * If the server supports web registration, the corresponding view is opened.
 	 * If the server does not support web registration and it is not a custom server, another one is automatically selected.
 	 */
-	function handleInBandRegistrationNotSupportedError() {
+	function handleInBandRegistrationNotSupported() {
 		var notificationText = serverView.customServerSelected ? qsTr("The server does not support registration via this app.") : qsTr("The server does currently not support registration via this app.")
 
-		if (serverView.inBandRegistrationSupported) {
+		if (serverView.registrationWebPage || serverView.outOfBandUrl) {
 			addWebRegistrationView()
 			notificationText += " " + qsTr("But you can use the server's web registration.")
 		} else {
@@ -283,7 +284,7 @@ RegistrationPage {
 	function addWebRegistrationView() {
 		removeDynamicallyLoadedInBandRegistrationViews()
 
-		webRegistrationView = webRegistrationViewComponent.createObject(webRegistrationView)
+		webRegistrationView = webRegistrationViewComponent.createObject(swipeView)
 		swipeView.insertItem(serverView.Controls.SwipeView.index + 1, webRegistrationView)
 	}
 

src/qml/registration/ServerView.qml

@@ -51,6 +51,7 @@ FieldView {
 	property bool inBandRegistrationSupported: serverListModel.data(comboBox.currentIndex, ServerListModel.SupportsInBandRegistrationRole)
 	property string registrationWebPage: serverListModel.data(comboBox.currentIndex, ServerListModel.RegistrationWebPageRole)
 	property bool shouldWebRegistrationViewBeShown: !customServerSelected && !inBandRegistrationSupported
+	property string outOfBandUrl
 
 	property alias customConnectionSettings: customConnectionSettings
 
@@ -106,6 +107,13 @@ FieldView {
 				}
 			]
 
+			onTextChanged: {
+				if (outOfBandUrl && customServerSelected) {
+					outOfBandUrl = ""
+					removeWebRegistrationView()
+				}
+			}
+
 			// Focus the customConnectionSettings on confirmation.
 			Keys.onPressed: {
 				if (customConnectionSettings.visible) {

src/qml/registration/WebRegistrationView.qml

@@ -47,12 +47,12 @@ View {
 
 		CenteredAdaptiveHighlightedButton {
 			text: qsTr("Open registration web page")
-			onClicked: Qt.openUrlExternally(serverView.registrationWebPage)
+			onClicked: Qt.openUrlExternally(serverView.registrationWebPage ? serverView.registrationWebPage : serverView.outOfBandUrl)
 		}
 
 		CenteredAdaptiveButton {
 			text: qsTr("Copy registration web page address")
-			onClicked: Utils.copyToClipboard(serverView.registrationWebPage)
+			onClicked: Utils.copyToClipboard(serverView.registrationWebPage ? serverView.registrationWebPage : serverView.outOfBandUrl)
 		}
 
 		CenteredAdaptiveHighlightedButton {

src/qml/settings/CustomConnectionSettings.qml

@@ -40,7 +40,9 @@ import "../elements/fields"
 RowLayout {
 	property alias hostField: hostField
 	property alias portField: portField
-	property Button confirmationButton
+
+	// The type Item is used because the type Button does not work for buttons of type RoundButton.
+	property Item confirmationButton
 
 	Field {
 		id: hostField