# Duplicate Place Prevention Fix

## Problem
The same place could be added multiple times to the same trip day in the Explore page. When a user clicked "Add to Trip" for a place that was already in their active day's plan, it would create a duplicate entry.

## Solution Implemented
Added a duplicate check in `Explore.tsx` → `handleAddToTrip` function before inserting a new place into `trip_places` table.

### Changes Made

**File**: `src/pages/Explore.tsx`

**Location**: Lines 223-239 (new duplicate check added)

**Implementation**:
```typescript
// 4. Aynı place'in bu günde zaten var olup olmadığını kontrol et
const { data: exists } = await (supabase as any)
  .from('trip_places')
  .select('id')
  .eq('trip_day_id', activeDayId)
  .eq('place_id', place.id)
  .maybeSingle();

if (exists) {
  toast({
    title: 'Zaten Eklendi',
    description: 'Bu yer bugünün planında zaten mevcut.',
    variant: 'destructive',
  });
  navigate(`/planner?trip_id=${tripId}`);
  return;
}
```

## How It Works

1. **Before Insert**: Query `trip_places` table to check if a record already exists with the same `trip_day_id` and `place_id`
2. **If Duplicate Found**: 
   - Show error toast: "Zaten Eklendi - Bu yer bugünün planında zaten mevcut."
   - Navigate to planner page
   - Prevent insert operation
3. **If No Duplicate**: Continue with normal insert flow

## Benefits

✅ Prevents duplicate places in the same trip day  
✅ Provides clear user feedback when attempting to add duplicate  
✅ Maintains data integrity in `trip_places` table  
✅ Improves user experience by preventing confusion  

## Testing Checklist

- [ ] Try adding the same place twice to a trip day
- [ ] Verify error toast appears with correct message
- [ ] Confirm navigation to planner page occurs
- [ ] Verify no duplicate entry in database
- [ ] Test with different places to ensure normal flow works

## Related Files

- `src/pages/Explore.tsx` - Main implementation
- Database table: `trip_places` (composite key: `trip_day_id` + `place_id`)

---

**Status**: ✅ Implemented and Lint Passed  
**Date**: 2026-02-02
