pos changes

lib/presentation/pos/widgets/cart_line_tile.dart

@@ -14,14 +14,12 @@ class CartLineTile extends StatelessWidget {
     required this.onIncrement,
     required this.onDecrement,
     required this.onRemove,
-    this.onDiscount,
   });
 
   final CartLine line;
   final VoidCallback onIncrement;
   final VoidCallback onDecrement;
   final VoidCallback onRemove;
-  final VoidCallback? onDiscount;
 
   @override
   Widget build(BuildContext context) {
@@ -30,7 +28,16 @@ class CartLineTile extends StatelessWidget {
     return Dismissible(
       key: ValueKey('dismiss_${p.id}'),
       direction: DismissDirection.endToStart,
-      onDismissed: (_) => onRemove(),
+      // Confirm rather than dismiss: [onRemove] opens the PIN dialog, and a
+      // refused PIN must leave the line exactly where it was. Dismissing first
+      // and asking after left the row gone from the screen but still in the
+      // cart — and Flutter asserting about a dismissed widget still in the
+      // tree. Returning false always is correct: when the PIN is accepted the
+      // line disappears because the cart changed, not because of the swipe.
+      confirmDismiss: (_) async {
+        onRemove();
+        return false;
+      },
       background: Container(
         alignment: Alignment.centerRight,
         padding: const EdgeInsets.only(right: AppSpacing.xl),
@@ -119,7 +126,7 @@ class CartLineTile extends StatelessWidget {
               color: AppColors.textTertiary,
               constraints: const BoxConstraints(minWidth: 32, minHeight: 32),
               padding: EdgeInsets.zero,
-              tooltip: 'Remove',
+              tooltip: 'Remove from bill (needs the removal PIN)',
             ),
           ],),
 
@@ -132,17 +139,6 @@ class CartLineTile extends StatelessWidget {
               onIncrement: onIncrement,
               onDecrement: onDecrement,
             ),
-            if (onDiscount != null) ...[
-              const SizedBox(width: AppSpacing.sm),
-              IconButton(
-                onPressed: onDiscount,
-                icon: const Icon(Icons.local_offer_outlined, size: 17),
-                color: AppColors.textSecondary,
-                constraints: const BoxConstraints(minWidth: 34, minHeight: 34),
-                padding: EdgeInsets.zero,
-                tooltip: 'Line discount',
-              ),
-            ],
             const Spacer(),
             Column(
               crossAxisAlignment: CrossAxisAlignment.end,
@@ -209,8 +205,12 @@ class _Stepper extends StatelessWidget {
         borderRadius: AppRadius.brSm,
         border: Border.all(color: AppColors.border),
       ),
+      // Minus stops at one rather than emptying the line. Dropping to zero
+      // was a silent removal that skipped the PIN the close button asks for —
+      // two taps of a stepper should not be a way around the till's only
+      // theft control.
       child: Row(mainAxisSize: MainAxisSize.min, children: [
-        _btn(Icons.remove_rounded, onDecrement),
+        _btn(Icons.remove_rounded, quantity > 1 ? onDecrement : null),
         Container(
           constraints: const BoxConstraints(minWidth: 42),
           alignment: Alignment.center,
@@ -226,7 +226,7 @@ class _Stepper extends StatelessWidget {
     );
   }
 
-  Widget _btn(IconData icon, VoidCallback onTap) => Material(
+  Widget _btn(IconData icon, VoidCallback? onTap) => Material(
         color: Colors.transparent,
         child: InkWell(
           onTap: onTap,
@@ -234,7 +234,13 @@ class _Stepper extends StatelessWidget {
           child: SizedBox(
             width: 34,
             height: 34,
-            child: Icon(icon, size: 17, color: AppColors.primary),
+            child: Icon(
+              icon,
+              size: 17,
+              color: onTap == null
+                  ? AppColors.textTertiary.withValues(alpha: 0.5)
+                  : AppColors.primary,
+            ),
           ),
         ),
       );