From 2b17e861be431b48b40f88e3fe1bbfa47ee25305 Mon Sep 17 00:00:00 2001
From: Levi Neely <lneely@pascom.net>
Date: Mon, 27 Jul 2026 09:17:28 +0200
Subject: [PATCH] gui: add native scrollbar + lazy-load on scroll-up

- Add ScrollBar.vertical to the chat Flickable (both KF5/KF6)
- Remove interactive:false so native flick gestures work
- Trigger paneModel.loadEarlier() when scrolled near top
- Preserve scroll position when prepending older blocks
- Reduce column width by 12px for scrollbar clearance
---
 gui/ChatPane.qml | 18 ++++++++++++++++--
 gui/main-kf5.qml | 17 +++++++++++++++--
 2 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/gui/ChatPane.qml b/gui/ChatPane.qml
index 8e25e19..1afd68c 100644
--- a/gui/ChatPane.qml
+++ b/gui/ChatPane.qml
@@ -179,7 +179,6 @@ Item {
                 contentWidth: width
                 contentHeight: paneColumn.implicitHeight
                 boundsBehavior: Flickable.StopAtBounds
-                interactive: false  // scroll via wheel MouseArea; enables text selection
 
                 property bool _settingY: false
 
@@ -187,6 +186,17 @@ Item {
                     if (_settingY) return
                     let bottom = contentHeight - height
                     parent.atBottom = (bottom <= 0 || contentY >= bottom - 4)
+
+                    // Lazy-load earlier blocks when near top
+                    if (contentY < 80 && contentY >= 0 && !_settingY) {
+                        let oldHeight = contentHeight
+                        if (paneModel.loadEarlier()) {
+                            // Preserve scroll position
+                            _settingY = true
+                            contentY += (contentHeight - oldHeight)
+                            _settingY = false
+                        }
+                    }
                 }
 
                 onContentHeightChanged: {
@@ -197,6 +207,10 @@ Item {
                     }
                 }
 
+                ScrollBar.vertical: ScrollBar {
+                    policy: ScrollBar.AsNeeded
+                }
+
                 MouseArea {
                     anchors.fill: parent
                     acceptedButtons: Qt.NoButton
@@ -214,7 +228,7 @@ Item {
 
                 Column {
                     id: paneColumn
-                    width: paneFlick.width
+                    width: paneFlick.width - 12  // leave room for scrollbar
                     spacing: 8
 
                     Label {
diff --git a/gui/main-kf5.qml b/gui/main-kf5.qml
index d7aa7e9..e7731f7 100644
--- a/gui/main-kf5.qml
+++ b/gui/main-kf5.qml
@@ -978,7 +978,6 @@ ApplicationWindow {
                         contentWidth: width
                         contentHeight: paneColumn.implicitHeight
                         boundsBehavior: Flickable.StopAtBounds
-                        interactive: false  // scroll via wheel; text not selectable in Qt5 Text
 
                         property bool _settingY: false
 
@@ -986,6 +985,16 @@ ApplicationWindow {
                             if (_settingY) return
                             var bottom = contentHeight - height
                             parent.atBottom = (bottom <= 0 || contentY >= bottom - 4)
+
+                            // Lazy-load earlier blocks when near top
+                            if (contentY < 80 && contentY >= 0 && !_settingY) {
+                                var oldHeight = contentHeight
+                                if (paneRoot.paneModel.loadEarlier()) {
+                                    _settingY = true
+                                    contentY += (contentHeight - oldHeight)
+                                    _settingY = false
+                                }
+                            }
                         }
 
                         onContentHeightChanged: {
@@ -996,6 +1005,10 @@ ApplicationWindow {
                             }
                         }
 
+                        ScrollBar.vertical: ScrollBar {
+                            policy: ScrollBar.AsNeeded
+                        }
+
                         MouseArea {
                             anchors.fill: parent
                             acceptedButtons: Qt.NoButton
@@ -1012,7 +1025,7 @@ ApplicationWindow {
 
                         Column {
                             id: paneColumn
-                            width: paneFlick.width
+                            width: paneFlick.width - 12  // leave room for scrollbar
                             spacing: 8
 
                             Label {