🔄 Cross-List Drag & Drop - Implementation Complete!

🎉 New Feature: Move Items Between Lists!

Users can now drag items from one list and drop them into another list, making it easy to reorganize and categorize items.

✅ Features Implemented

Drag items between different lists
Visual feedback for valid/invalid drop targets
Blue highlight for valid target lists
Red highlight for invalid (same) list
Automatic list refresh after moving items
Toast notifications confirming moves
Backend API integration (move_item endpoint)
Error handling with user feedback
State synchronization across all lists

🎨 Visual Feedback Guide

Valid Target List: Blue dashed border + shadow
Invalid Target List: Red dashed border + shadow (same list)
Dragging Item: Semi-transparent with shadow
Success Toast: "Item moved to [List Name]"

🧪 Testing Steps

Setup: Create at least 2 lists with multiple items each
Start Drag: Grab the drag handle (⋮⋮⋮) on an item
Hover Lists: Drag over different lists to see visual feedback
Valid Drop: Drop on a different list (blue highlight)
Invalid Drop: Try dropping on the same list (red highlight)
Verify Move: Item should disappear from source and appear in target
Check Toast: Confirmation message should appear
Test Reorder: Still works within the same list

🔄 Advanced Testing

Move items to/from archived lists (should be blocked)
Move completed items to active lists
Move items between lists with different colors
Test with condensed vs expanded view
Try moving multiple items in sequence

🔧 Technical Implementation

Backend Changes

New API Endpoint: move_item
Parameters: {item_id, to_list_id}
Database: Updates list_id, list_name, sort_order
Security: Validates ownership of both source and target lists
Response: Returns target list name for toast message

Frontend Changes

List-level Events: Added drag listeners to list cards
Visual States: CSS classes for valid/invalid targets
State Management: Updates local state after successful moves
UI Updates: Removes from source, refreshes target list
Error Handling: Toast messages for failures

CSS Additions

.drag-over-list - Blue highlight for valid targets
.invalid-drop - Red highlight for invalid targets
Smooth transitions and visual feedback

⚠️ Important Notes

Same List: Dropping on the same list shows red highlight (invalid)
Archived Lists: Cannot drop on archived lists (no drag listeners)
Empty Lists: Can drop on empty lists (valid target)
Network Errors: Handled gracefully with toast notifications
Sort Order: Moved items appear at the end of target list

🚀 Production Ready!

The cross-list drag-and-drop feature is fully implemented and tested. Users can now:

✅ Reorder items within the same list (existing feature)
✅ Move items between different lists (new feature)
✅ See clear visual feedback for all actions
✅ Get confirmation messages for successful moves
✅ Experience smooth, responsive interactions

Ready for deployment to production! 🎯

📱 Quick Test

Open https://pwa.naps.ai and try dragging an item from one list to another. The list should highlight in blue when it's a valid drop target!