Add recently pinned message to the top of the window

This makes pinned messages actually quite useful, as rooms can stick
persistent and important information for users to see. (For example, the
KWin has crash triage meeting information pinned in their room.)

For simplicity and space reasons, only one line of the generic message
body is shown.

src/app/qml/RoomPage.qml

@@ -7,6 +7,7 @@ pragma ComponentBehavior: Bound
 import QtQuick
 import QtQuick.Controls as QQC2
 import QtQuick.Window
+import QtQuick.Layouts
 
 import org.kde.kirigami as Kirigami
 
@@ -98,24 +99,87 @@ Kirigami.Page {
         }
     }
 
-    header: Kirigami.InlineMessage {
-        id: banner
+    header: ColumnLayout {
+        id: headerLayout
 
-        // Used to keep track of messages so we can hide the right one at the right time
-        property string messageId
+        spacing: 0
 
-        showCloseButton: true
-        visible: false
-        position: Kirigami.InlineMessage.Position.Header
+        readonly property bool shouldShowPins: root.currentRoom.pinnedMessage.length > 0 && !Kirigami.Settings.isMobile
 
-        function show(msgid: string): void {
-            messageId = msgid;
-            visible = true;
+        QQC2.Control {
+            id: pinControl
+
+            visible: headerLayout.shouldShowPins
+
+            Layout.fillWidth: true
+
+            background: Rectangle {
+                color: Kirigami.Theme.backgroundColor
+
+                Kirigami.Theme.colorSet: Kirigami.Theme.View
+                Kirigami.Theme.inherit: false
+            }
+
+            contentItem: RowLayout {
+                spacing: Kirigami.Units.smallSpacing
+
+                Kirigami.Icon {
+                    source: "pin-symbolic"
+
+                    Layout.preferredWidth: Kirigami.Units.iconSizes.smallMedium
+                    Layout.preferredHeight: Kirigami.Units.iconSizes.smallMedium
+                }
+
+                QQC2.Label {
+                    text: root.currentRoom.pinnedMessage
+                    maximumLineCount: 1
+                    elide: Text.ElideRight
+
+                    onLinkActivated: link => UrlHelper.openUrl(link)
+                    onHoveredLinkChanged: if (hoveredLink.length > 0 && hoveredLink !== "1") {
+                        (QQC2.ApplicationWindow.window as Main).hoverLinkIndicator.text = hoveredLink;
+                    } else {
+                        (QQC2.ApplicationWindow.window as Main).hoverLinkIndicator.text = "";
+                    }
+
+                    Layout.fillWidth: true
+                }
+            }
+
+            TapHandler {
+                onTapped: pageStack.pushDialogLayer(Qt.createComponent('org.kde.neochat', 'RoomPinnedMessagesPage'), {
+                    room: root.currentRoom
+                }, {
+                    title: i18nc("@title", "Pinned Messages")
+                });
+            }
         }
 
-        function hideIf(msgid: string): void {
-            if (messageId == msgid) {
-                visible = false;
+        Kirigami.Separator {
+            visible: headerLayout.shouldShowPins
+
+            Layout.fillWidth: true
+        }
+
+        Kirigami.InlineMessage {
+            id: banner
+
+            // Used to keep track of messages so we can hide the right one at the right time
+            property string messageId
+
+            showCloseButton: true
+            visible: false
+            position: Kirigami.InlineMessage.Position.Header
+
+            function show(msgid: string): void {
+                messageId = msgid;
+                visible = true;
+            }
+
+            function hideIf(msgid: string): void {
+                if (messageId == msgid) {
+                    visible = false;
+                }
             }
         }
     }