Move remaining code to app module

There's still some stuff that could potentially go elsewhere but I think it's enough for now.

src/app/qml/ServerComboBox.qml

@@ -0,0 +1,197 @@
+
+// SPDX-FileCopyrightText: 2024 James Graham <james.h.graham@protonmail.com>
+// SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
+
+import QtQuick
+import QtQuick.Controls as QQC2
+import QtQuick.Layouts
+
+import org.kde.kirigami as Kirigami
+import org.kde.kirigamiaddons.delegates as Delegates
+import org.kde.kirigamiaddons.formcard as FormCard
+
+import org.kde.neochat
+
+QQC2.ComboBox {
+    id: root
+
+    /**
+     * @brief The connection for the current local user.
+     */
+    required property NeoChatConnection connection
+
+    /**
+     * @brief The server to get the search results from.
+     */
+    property string server
+
+    Layout.preferredWidth: Kirigami.Units.gridUnit * 10
+    Component.onCompleted: currentIndex = 0
+
+    textRole: "url"
+    valueRole: "url"
+    model: ServerListModel {
+        id: serverListModel
+        connection: root.connection
+    }
+
+    delegate: Delegates.RoundedItemDelegate {
+        id: serverItem
+
+        required property int index
+        required property string url
+        required property bool isAddServerDelegate
+        required property bool isHomeServer
+        required property bool isDeletable
+
+        text: isAddServerDelegate ? i18n("Add New Server") : url
+        highlighted: index === root.highlightedIndex
+
+        topInset: index === 0 ? Kirigami.Units.smallSpacing : Math.round(Kirigami.Units.smallSpacing / 2)
+        bottomInset: index === ListView.view.count - 1 ? Kirigami.Units.smallSpacing : Math.round(Kirigami.Units.smallSpacing / 2)
+
+        onClicked: if (isAddServerDelegate) {
+            addServerSheet.parent = QQC2.Overlay.overlay
+            addServerSheet.open();
+        }
+
+        contentItem: RowLayout {
+            spacing: Kirigami.Units.smallSpacing
+
+            Delegates.SubtitleContentItem {
+                itemDelegate: serverItem
+                subtitle: serverItem.isHomeServer ? i18n("Home Server") : ""
+                Layout.fillWidth: true
+            }
+
+            QQC2.ToolButton {
+                visible: serverItem.isAddServerDelegate || serverItem.isDeletable
+                icon.name: serverItem.isAddServerDelegate ? "list-add" : "dialog-close"
+                text: i18nc("@action:button", "Add new server")
+                Accessible.name: text
+                display: QQC2.AbstractButton.IconOnly
+
+                onClicked: {
+                    if (root.currentIndex === serverItem.index && serverItem.isDeletable) {
+                        root.currentIndex = 0;
+                        root.server = root.currentValue;
+                        root.popup.close();
+                    }
+                    if (serverItem.isAddServerDelegate) {
+                        addServerSheet.parent = QQC2.Overlay.overlay
+                        addServerSheet.open();
+                        serverItem.clicked();
+                    } else {
+                        serverListModel.removeServerAtIndex(serverItem.index);
+                    }
+                }
+            }
+        }
+    }
+
+    onActivated: {
+        if (currentIndex !== count - 1) {
+            root.server = root.currentValue;
+        } else {
+            // Make sure to reset the combobox as it will display nothing if the "Add Server" item was selected.
+            root.currentIndex = 0;
+            root.server = root.currentValue;
+
+            addServerSheet.parent = QQC2.Overlay.overlay
+            addServerSheet.open();
+        }
+    }
+
+    Kirigami.Dialog {
+        id: addServerSheet
+
+        width: Math.min(Kirigami.Units.gridUnit * 15, QQC2.ApplicationWindow.window.width)
+
+        title: i18nc("@title:window", "Add server")
+
+        horizontalPadding: Kirigami.Units.largeSpacing
+
+        onOpened: if (!serverUrlField.isValidServer && !addServerSheet.opened) {
+            root.currentIndex = 0;
+            root.server = root.currentValue;
+        } else if (addServerSheet.opened) {
+            serverUrlField.forceActiveFocus();
+        }
+
+        onClosed: if (serverUrlField.length <= 0) {
+            root.currentIndex = root.indexOfValue(root.server);
+        }
+
+        contentItem: ColumnLayout {
+
+            spacing: Kirigami.Units.smallSpacing
+
+            Kirigami.InlineMessage {
+                Layout.fillWidth: true
+
+                visible: text != ""
+
+                text: {
+                    if (serverUrlField.length > 0) {
+                        if (!serverUrlField.acceptableInput) {
+                            return i18n("The entered text is not a valid url");
+                        }
+
+                        if (!serverUrlField.isValidServer) {
+                            return i18n("This server cannot be resolved or has already been added");
+                        }
+                    }
+
+                    return "";
+                }
+            }
+
+            QQC2.Label {
+                Layout.fillWidth: true
+
+                text: i18n("Server URL:")
+            }
+
+            QQC2.TextField {
+                id: serverUrlField
+
+                Layout.fillWidth: true
+
+                placeholderText: "kde.org"
+
+                property bool isValidServer: false
+
+                onTextChanged: {
+                    if (acceptableInput) {
+                        serverListModel.checkServer(text);
+                    }
+                }
+
+                validator: RegularExpressionValidator {
+                    regularExpression: /^([^.]+\.)+[^.]+$/
+                }
+
+                Connections {
+                    target: serverListModel
+                    function onServerCheckComplete(url, valid) {
+                        if (url == serverUrlField.text && valid) {
+                            serverUrlField.isValidServer = true;
+                        }
+                    }
+                }
+            }
+        }
+
+        customFooterActions: Kirigami.Action {
+            text: i18nc("@action:button", "Ok")
+            enabled: serverUrlField.acceptableInput && serverUrlField.isValidServer
+            onTriggered: {
+                serverListModel.addServer(serverUrlField.text);
+                root.currentIndex = root.indexOfValue(serverUrlField.text);
+                root.server = root.currentValue;
+                serverUrlField.text = "";
+                addServerSheet.close();
+            }
+        }
+    }
+}