fix(product-suite): prevent duplicate drag sorting

app/gui/tabs/product_suite.py

@@ -309,6 +309,7 @@ class ProductOriginalList(QListWidget):
         self.setDropIndicatorShown(True)
         self.setDragDropMode(QListWidget.InternalMove)
         self.setDefaultDropAction(Qt.MoveAction)
+        self._dragged_item = None
         self.setContextMenuPolicy(Qt.CustomContextMenu)
         self.customContextMenuRequested.connect(self._show_menu)
         self.itemChanged.connect(lambda item: self.checkedAssetsChanged.emit(self.checked_asset_ids()))
@@ -366,6 +367,10 @@ class ProductOriginalList(QListWidget):
         if event.mimeData().hasUrls():
             event.acceptProposedAction()
             return
+        if event.source() is self and self._reordering_enabled and self._dragged_item is not None:
+            event.setDropAction(Qt.MoveAction)
+            event.accept()
+            return
         super().dragEnterEvent(event)
 
     def dragMoveEvent(self, event):
@@ -375,6 +380,10 @@ class ProductOriginalList(QListWidget):
         if not self._reordering_enabled:
             event.ignore()
             return
+        if event.source() is self and self._dragged_item is not None:
+            event.setDropAction(Qt.MoveAction)
+            event.accept()
+            return
         super().dragMoveEvent(event)
 
     def dropEvent(self, event):
@@ -386,12 +395,59 @@ class ProductOriginalList(QListWidget):
         if not self._reordering_enabled:
             event.ignore()
             return
-        internal_move = event.source() is self
-        if internal_move:
-            event.setDropAction(Qt.MoveAction)
-        super().dropEvent(event)
-        if internal_move and event.isAccepted() and event.dropAction() == Qt.MoveAction:
-            self.orderChanged.emit(self.asset_ids())
+        if event.source() is not self:
+            event.ignore()
+            return
+        self._move_dragged_item_to(event.position().toPoint())
+        event.setDropAction(Qt.MoveAction)
+        event.accept()
+
+    def startDrag(self, supported_actions):
+        item = self.currentItem()
+        if (
+            not self._reordering_enabled
+            or item is None
+            or item.data(Qt.UserRole) is None
+        ):
+            return
+        self._dragged_item = item
+        try:
+            super().startDrag(Qt.MoveAction)
+        finally:
+            self._dragged_item = None
+
+    def _move_dragged_item_to(self, position):
+        item = self._dragged_item
+        if item is None:
+            return False
+        source_row = self.row(item)
+        before_ids = self.asset_ids()
+        if source_row < 0 or len(before_ids) != len(set(before_ids)):
+            return False
+        target = self.itemAt(position)
+        if target is None:
+            target_row = self.count()
+        else:
+            target_row = self.row(target)
+            if position.x() > self.visualItemRect(target).center().x():
+                target_row += 1
+        if target_row > source_row:
+            target_row -= 1
+        moved_item = self.takeItem(source_row)
+        target_row = max(0, min(target_row, self.count()))
+        self.insertItem(target_row, moved_item)
+        self.setCurrentItem(moved_item)
+        moved_item.setSelected(True)
+        after_ids = self.asset_ids()
+        if len(after_ids) != len(set(after_ids)):
+            self.takeItem(target_row)
+            self.insertItem(source_row, moved_item)
+            self.setCurrentItem(moved_item)
+            return False
+        if after_ids == before_ids:
+            return False
+        self.orderChanged.emit(after_ids)
+        return True
 
     def resizeEvent(self, event):
         super().resizeEvent(event)
@@ -3389,9 +3445,7 @@ class ProductSuiteTab(QWidget):
             for index, asset in enumerate(assets, 1):
                 label = "主图" if index == 1 else "参考%d" % (index - 1)
                 item = QListWidgetItem(label)
-                item.setFlags(
-                    item.flags() | Qt.ItemIsDragEnabled | Qt.ItemIsDropEnabled
-                )
+                item.setFlags(item.flags() | Qt.ItemIsDragEnabled)
                 if index == 1:
                     font = QFont(item.font())
                     font.setBold(True)