[Chat] - MessagePageScaffold: Prevent possibly negative layout constraints on bottom sheet.

Author: matthew-carroll

super_editor/lib/src/chat/message_page_scaffold.dart

@@ -63,8 +63,7 @@ class MessagePageScaffold extends RenderObjectWidget {
   }
 
   @override
-  void updateRenderObject(
-      BuildContext context, RenderMessagePageScaffold renderObject) {
+  void updateRenderObject(BuildContext context, RenderMessagePageScaffold renderObject) {
     renderObject
       ..bottomSheetMinimumTopGap = bottomSheetMinimumTopGap
       ..bottomSheetMinimumHeight = bottomSheetMinimumHeight;
@@ -76,8 +75,7 @@ class MessagePageScaffold extends RenderObjectWidget {
 }
 
 /// Builder that builds the content subtree within a [MessagePageScaffold].
-typedef MessagePageScaffoldContentBuilder = Widget Function(
-    BuildContext context, double bottomSpacing);
+typedef MessagePageScaffoldContentBuilder = Widget Function(BuildContext context, double bottomSpacing);
 
 /// Height sizing policy for a bottom sheet within a [MessagePageScaffold].
 enum BottomSheetMode {
@@ -104,8 +102,7 @@ enum BottomSheetMode {
 /// Controller for a [MessagePageScaffold].
 class MessagePageController with ChangeNotifier {
   MessagePageSheetHeightPolicy get sheetHeightPolicy => _sheetHeightPolicy;
-  MessagePageSheetHeightPolicy _sheetHeightPolicy =
-      MessagePageSheetHeightPolicy.minimumHeight;
+  MessagePageSheetHeightPolicy _sheetHeightPolicy = MessagePageSheetHeightPolicy.minimumHeight;
   set sheetHeightPolicy(MessagePageSheetHeightPolicy policy) {
     if (policy == _sheetHeightPolicy) {
       return;
@@ -116,12 +113,12 @@ class MessagePageController with ChangeNotifier {
   }
 
   bool get isPreview =>
-      _collapsedMode == MessagePageSheetCollapsedMode.preview &&
+      _collapsedMode == MessagePageSheetCollapsedMode.preview && //
       !isSliding &&
       !isDragging;
 
   bool get isIntrinsic =>
-      _collapsedMode == MessagePageSheetCollapsedMode.intrinsic &&
+      _collapsedMode == MessagePageSheetCollapsedMode.intrinsic && //
       !isSliding &&
       !isDragging;
 
@@ -137,12 +134,12 @@ class MessagePageController with ChangeNotifier {
   }
 
   bool get isCollapsed =>
-      _desiredSheetMode == MessagePageSheetMode.collapsed &&
+      _desiredSheetMode == MessagePageSheetMode.collapsed && //
       !isSliding &&
       !isDragging;
 
   bool get isExpanded =>
-      _desiredSheetMode == MessagePageSheetMode.expanded &&
+      _desiredSheetMode == MessagePageSheetMode.expanded && //
       !isSliding &&
       !isDragging;
 
@@ -304,8 +301,7 @@ class MessagePageElement extends RenderObjectElement {
   MessagePageScaffold get widget => super.widget as MessagePageScaffold;
 
   @override
-  RenderMessagePageScaffold get renderObject =>
-      super.renderObject as RenderMessagePageScaffold;
+  RenderMessagePageScaffold get renderObject => super.renderObject as RenderMessagePageScaffold;
 
   @override
   void mount(Element? parent, Object? newSlot) {
@@ -320,8 +316,7 @@ class MessagePageElement extends RenderObjectElement {
       _contentSlot,
     );
 
-    _bottomSheet =
-        inflateWidget(widget.bottomSheetBuilder(this), _bottomSheetSlot);
+    _bottomSheet = inflateWidget(widget.bottomSheetBuilder(this), _bottomSheetSlot);
   }
 
   @override
@@ -368,13 +363,11 @@ class MessagePageElement extends RenderObjectElement {
     //
     // We don't rebuild our content widget because we only want content to
     // build during layout.
-    updateChild(
-        _bottomSheet, widget.bottomSheetBuilder(this), _bottomSheetSlot);
+    updateChild(_bottomSheet, widget.bottomSheetBuilder(this), _bottomSheetSlot);
   }
 
   void buildContent(double bottomSpacing) {
-    messagePageElementLog
-        .info('ContentLayersElement ($hashCode) - (re)building layers');
+    messagePageElementLog.info('ContentLayersElement ($hashCode) - (re)building layers');
 
     owner!.buildScope(this, () {
       if (_content == null) {
@@ -396,11 +389,8 @@ class MessagePageElement extends RenderObjectElement {
   void update(MessagePageScaffold newWidget) {
     super.update(newWidget);
 
-    _content =
-        updateChild(_content, widget.contentBuilder(this, 0), _contentSlot) ??
-            _content;
-    _bottomSheet = updateChild(
-        _bottomSheet, widget.bottomSheetBuilder(this), _bottomSheetSlot);
+    _content = updateChild(_content, widget.contentBuilder(this, 0), _contentSlot) ?? _content;
+    _bottomSheet = updateChild(_bottomSheet, widget.bottomSheetBuilder(this), _bottomSheetSlot);
   }
 
   @override
@@ -619,8 +609,7 @@ class RenderMessagePageScaffold extends RenderBox {
       _currentDesiredGlobalTopY = _controller.desiredGlobalTopY;
 
       final pageGlobalBottom = localToGlobal(Offset(0, size.height)).dy;
-      _desiredDragHeight = pageGlobalBottom -
-          max(_currentDesiredGlobalTopY!, _bottomSheetMinimumTopGap);
+      _desiredDragHeight = pageGlobalBottom - max(_currentDesiredGlobalTopY!, _bottomSheetMinimumTopGap);
       _expandedHeight = size.height - _bottomSheetMinimumTopGap;
 
       _velocityTracker.addPosition(
@@ -649,8 +638,7 @@ class RenderMessagePageScaffold extends RenderBox {
     _isExpandingOrCollapsing = true;
     _velocityStopwatch.stop();
 
-    final velocity =
-        _velocityTracker.getVelocityEstimate()?.pixelsPerSecond.dy ?? 0;
+    final velocity = _velocityTracker.getVelocityEstimate()?.pixelsPerSecond.dy ?? 0;
 
     _startBottomSheetHeightSimulation(velocity: velocity);
   }
@@ -669,8 +657,7 @@ class RenderMessagePageScaffold extends RenderBox {
         ? velocity < 0
             ? MessagePageSheetMode.expanded
             : MessagePageSheetMode.collapsed
-        : (_expandedHeight - _desiredDragHeight!).abs() <
-                (_desiredDragHeight! - minimizedHeight).abs()
+        : (_expandedHeight - _desiredDragHeight!).abs() < (_desiredDragHeight! - minimizedHeight).abs()
             ? MessagePageSheetMode.expanded
             : MessagePageSheetMode.collapsed;
 
@@ -698,10 +685,7 @@ class RenderMessagePageScaffold extends RenderBox {
 
     final startHeight = _bottomSheet!.size.height;
     _simulationGoalMode = _controller.desiredSheetMode;
-    _simulationGoalHeight =
-        _simulationGoalMode! == MessagePageSheetMode.expanded
-            ? _expandedHeight
-            : minimizedHeight;
+    _simulationGoalHeight = _simulationGoalMode! == MessagePageSheetMode.expanded ? _expandedHeight : minimizedHeight;
 
     messagePageLayoutLog.info('Creating expand/collapse simulation:');
     messagePageLayoutLog.info(
@@ -856,8 +840,7 @@ class RenderMessagePageScaffold extends RenderBox {
       childDiagnostics.add(_content!.toDiagnosticsNode(name: 'content'));
     }
     if (_bottomSheet != null) {
-      childDiagnostics
-          .add(_bottomSheet!.toDiagnosticsNode(name: 'message_editor'));
+      childDiagnostics.add(_bottomSheet!.toDiagnosticsNode(name: 'message_editor'));
     }
 
     return childDiagnostics;
@@ -907,8 +890,8 @@ class RenderMessagePageScaffold extends RenderBox {
   void performLayout() {
     messagePageLayoutLog.info('---------- LAYOUT -------------');
     messagePageLayoutLog.info('Laying out RenderChatScaffold');
-    messagePageLayoutLog.info(
-        'Sheet mode: ${_controller.desiredSheetMode}, collapsed mode: ${_controller.collapsedMode}');
+    messagePageLayoutLog
+        .info('Sheet mode: ${_controller.desiredSheetMode}, collapsed mode: ${_controller.collapsedMode}');
     if (_content == null) {
       size = Size.zero;
       _bottomSheetNeedsLayout = false;
@@ -927,9 +910,7 @@ class RenderMessagePageScaffold extends RenderBox {
     // sheet, bounded within its min/max height.
     _overrideSheetMode = BottomSheetMode.preview;
 
-    _previewHeight = _bottomSheet!
-        .computeDryLayout(constraints.copyWith(minHeight: 0))
-        .height;
+    _previewHeight = _bottomSheet!.computeDryLayout(constraints.copyWith(minHeight: 0)).height;
 
     _overrideSheetMode = null;
     messagePageLayoutLog.info(
@@ -982,7 +963,8 @@ class RenderMessagePageScaffold extends RenderBox {
 
       _bottomSheet!.layout(
         bottomSheetConstraints.copyWith(
-          minHeight: _animatedHeight - 1,
+          minHeight: max(_animatedHeight - 1, 0),
+          // ^ prevent a layout boundary
           maxHeight: _animatedHeight,
         ),
         parentUsesSize: true,
@@ -992,13 +974,13 @@ class RenderMessagePageScaffold extends RenderBox {
       messagePageLayoutLog.info(
         ' - drag height: $_desiredDragHeight, minimized height: $minimizedHeight',
       );
-      final strictHeight =
-          _desiredDragHeight!.clamp(minimizedHeight, _bottomSheetMaximumHeight);
+      final strictHeight = _desiredDragHeight!.clamp(minimizedHeight, _bottomSheetMaximumHeight);
 
       messagePageLayoutLog.info(' - bounded drag height: $strictHeight');
       _bottomSheet!.layout(
         bottomSheetConstraints.copyWith(
-          minHeight: strictHeight - 1,
+          minHeight: max(strictHeight - 1, 0),
+          // ^ prevent layout boundary
           maxHeight: strictHeight,
         ),
         parentUsesSize: true,
@@ -1011,27 +993,24 @@ class RenderMessagePageScaffold extends RenderBox {
 
       _bottomSheet!.layout(
         bottomSheetConstraints.copyWith(
-          minHeight: _expandedHeight - 1,
+          minHeight: max(_expandedHeight - 1, 0),
           // ^ Prevent a layout boundary.
           maxHeight: _expandedHeight,
         ),
         parentUsesSize: true,
       );
     } else {
       messagePageLayoutLog.info('>>>>>>>> Minimized');
-      messagePageLayoutLog.info(
-          'Running standard editor layout with constraints: $bottomSheetConstraints');
+      messagePageLayoutLog.info('Running standard editor layout with constraints: $bottomSheetConstraints');
       _bottomSheet!.layout(
         bottomSheetConstraints,
         parentUsesSize: true,
       );
     }
 
-    (_bottomSheet!.parentData! as BoxParentData).offset =
-        Offset(0, size.height - _bottomSheet!.size.height);
+    (_bottomSheet!.parentData! as BoxParentData).offset = Offset(0, size.height - _bottomSheet!.size.height);
     _bottomSheetNeedsLayout = false;
-    messagePageLayoutLog
-        .info('Bottom sheet height: ${_bottomSheet!.size.height}');
+    messagePageLayoutLog.info('Bottom sheet height: ${_bottomSheet!.size.height}');
 
     // Now that we know the size of the message editor, build the content based
     // on the bottom spacing needed to push above the editor.
@@ -1051,11 +1030,9 @@ class RenderMessagePageScaffold extends RenderBox {
   }
 
   double _calculateBoundedIntrinsicHeight(BoxConstraints constraints) {
-    messagePageLayoutLog.info(
-        'Running dry layout on bottom sheet content to find the intrinsic height...');
+    messagePageLayoutLog.info('Running dry layout on bottom sheet content to find the intrinsic height...');
     messagePageLayoutLog.info(' - Bottom sheet constraints: $constraints');
-    messagePageLayoutLog
-        .info(' - Controller desired sheet mode: ${_controller.collapsedMode}');
+    messagePageLayoutLog.info(' - Controller desired sheet mode: ${_controller.collapsedMode}');
     _overrideSheetMode = BottomSheetMode.intrinsic;
     messagePageLayoutLog.info(' - Override sheet mode: $_overrideSheetMode');
 
@@ -1066,8 +1043,7 @@ class RenderMessagePageScaffold extends RenderBox {
         .height;
 
     _overrideSheetMode = null;
-    messagePageLayoutLog
-        .info(" - Child's self-chosen height is: $bottomSheetHeight");
+    messagePageLayoutLog.info(" - Child's self-chosen height is: $bottomSheetHeight");
     messagePageLayoutLog.info(
       " - Clamping child's height within [$_bottomSheetMinimumHeight, $_bottomSheetMaximumHeight]",
     );
@@ -1146,8 +1122,7 @@ class RenderMessagePageScaffold extends RenderBox {
   }
 }
 
-bool _isChatScaffoldSlot(Object slot) =>
-    slot == _contentSlot || slot == _bottomSheetSlot;
+bool _isChatScaffoldSlot(Object slot) => slot == _contentSlot || slot == _bottomSheetSlot;
 
 const _contentSlot = 'content';
 const _bottomSheetSlot = 'bottom_sheet';
@@ -1235,8 +1210,7 @@ class RenderMessageEditorHeight extends RenderBox
     messageEditorHeightLog.info(' - Constraints: $constraints');
 
     final ancestorChatScaffold = _findAncestorMessagePageScaffold();
-    messageEditorHeightLog
-        .info(' - Ancestor chat scaffold: $ancestorChatScaffold');
+    messageEditorHeightLog.info(' - Ancestor chat scaffold: $ancestorChatScaffold');
 
     final heightMode = ancestorChatScaffold?.bottomSheetMode;
     if (heightMode == null) {
@@ -1253,17 +1227,15 @@ class RenderMessageEditorHeight extends RenderBox
     switch (heightMode) {
       case BottomSheetMode.preview:
         // Preview mode imposes a specific height on the bottom sheet.
-        messageEditorHeightLog
-            .info(' - Desired bottom sheet preview height: $_previewHeight');
+        messageEditorHeightLog.info(' - Desired bottom sheet preview height: $_previewHeight');
 
         // We want to be a specific height. Get as close as we can.
         final constrainedHeight = constraints.constrainDimensions(
           double.infinity,
           _previewHeight,
         );
 
-        messageEditorHeightLog.info(
-            ' - Constrained bottom sheet preview height: $constrainedHeight');
+        messageEditorHeightLog.info(' - Constrained bottom sheet preview height: $constrainedHeight');
         return constrainedHeight;
       case BottomSheetMode.dragging:
       case BottomSheetMode.settling:
@@ -1283,8 +1255,7 @@ class RenderMessageEditorHeight extends RenderBox
     messageEditorHeightLog.info(' - Constraints: $constraints');
 
     final ancestorChatScaffold = _findAncestorMessagePageScaffold();
-    messageEditorHeightLog
-        .info(' - Ancestor chat scaffold: $ancestorChatScaffold');
+    messageEditorHeightLog.info(' - Ancestor chat scaffold: $ancestorChatScaffold');
 
     final heightMode = ancestorChatScaffold?.bottomSheetMode;
     if (heightMode == null) {
@@ -1303,8 +1274,7 @@ class RenderMessageEditorHeight extends RenderBox
     switch (heightMode) {
       case BottomSheetMode.preview:
         // Preview mode imposes a specific height on the bottom sheet.
-        messageEditorHeightLog
-            .info(' - Forcing bottom sheet to preview height: $_previewHeight');
+        messageEditorHeightLog.info(' - Forcing bottom sheet to preview height: $_previewHeight');
 
         // We want to be a specific height. Get as close as we can.
         size = constraints.constrainDimensions(
@@ -1316,7 +1286,8 @@ class RenderMessageEditorHeight extends RenderBox
         );
         child?.layout(
           constraints.copyWith(
-            minHeight: size.height - 1,
+            minHeight: max(size.height - 1, 0),
+            // ^ prevent layout boundary
             maxHeight: size.height,
           ),
           parentUsesSize: true,
@@ -1331,11 +1302,9 @@ class RenderMessageEditorHeight extends RenderBox
       case BottomSheetMode.expanded:
         // Whether dragging, animating, or fully expanded, these conditions
         // want to stipulate exactly how tall the bottom sheet should be.
-        messageEditorHeightLog
-            .info(' - Mode $heightMode - Filling available height');
+        messageEditorHeightLog.info(' - Mode $heightMode - Filling available height');
         if (!constraints.hasBoundedHeight) {
-          messageEditorHeightLog
-              .info('   - No bounded height was provided. Deferring to child');
+          messageEditorHeightLog.info('   - No bounded height was provided. Deferring to child');
           size = _doIntrinsicLayout(constraints);
           messageEditorHeightLog.info(' - Our reported size: $size');
           return;
@@ -1348,7 +1317,7 @@ class RenderMessageEditorHeight extends RenderBox
         size = constraints.biggest;
         child?.layout(
           constraints.copyWith(
-            minHeight: size.height - 1,
+            minHeight: max(size.height - 1, 0),
             // ^ Prevent a layout boundary.
             maxHeight: size.height,
           ),
@@ -1369,8 +1338,7 @@ class RenderMessageEditorHeight extends RenderBox
     BoxConstraints constraints, {
     bool doDryLayout = false,
   }) {
-    messageEditorHeightLog
-        .info(' - Measuring child intrinsic height. Constraints: $constraints');
+    messageEditorHeightLog.info(' - Measuring child intrinsic height. Constraints: $constraints');
 
     final child = this.child;
     if (child == null) {
@@ -1391,8 +1359,7 @@ class RenderMessageEditorHeight extends RenderBox
       intrinsicSize = child.size;
     }
 
-    messageEditorHeightLog
-        .info(' - Child intrinsic height: ${intrinsicSize.height}');
+    messageEditorHeightLog.info(' - Child intrinsic height: ${intrinsicSize.height}');
     return constraints.constrain(intrinsicSize);
   }