# Time Entries Sorting Fix

## Problem
The sort buttons on the time entries data browser page were not working. Clicking column headers to sort had no effect.

## Root Cause
The `DataTable` component expects an `onSort` callback prop, but the time-entries page was not providing it.

**Missing in original code:**
```typescript
<DataTable
  data={timeEntries}
  columns={columns}
  // ... other props
  // ❌ onSort prop was missing
/>
```

## Solution

### 1. Added Sort State
```typescript
// Sort states
const [sortBy, setSortBy] = useState('entry_date');
const [sortOrder, setSortOrder] = useState<'asc' | 'desc'>('desc');
```

### 2. Updated fetchTimeEntries to Include Sort Parameters
```typescript
params.append('sort_by', sortBy);
params.append('sort_order', sortOrder);
```

### 3. Created handleSort Function
```typescript
const handleSort = async (column: string, direction: 'asc' | 'desc') => {
  setSortBy(column);
  setSortOrder(direction);
  
  // Fetch with new sort parameters
  // ... builds params with new sort values
  // Resets to page 1 when sorting changes
};
```

### 4. Passed onSort to DataTable
```typescript
<DataTable
  data={timeEntries}
  columns={columns}
  isLoading={loading}
  onRowClick={handleRowClick}
  totalCount={totalCount}
  page={currentPage}
  pageSize={pageSize}
  onPageChange={handlePageChange}
  onSort={handleSort} // ✅ Now provided
/>
```

## How It Works

1. **User clicks column header** → DataTable calls `onSort(columnKey, direction)`
2. **handleSort updates state** → Sets `sortBy` and `sortOrder`
3. **handleSort fetches data** → Calls API with `sort_by` and `sort_order` params
4. **Page resets to 1** → Sorting always shows results from the first page
5. **Table updates** → New sorted data is displayed

## API Parameters

The API endpoint `/api/data/time-entries` accepts:
- `sort_by` - Column name to sort by (e.g., 'entry_date', 'hours_worked', 'resource_id')
- `sort_order` - Sort direction: 'asc' or 'desc'

**Valid sort columns:**
- `entry_date`
- `hours_worked`
- `created_at`
- `updated_at`
- `resource_id`
- `ticket_id`
- `task_id`
- `project_id`
- `company_id`
- `title`
- `billable`
- `approved`

## Default Sorting
- **Column**: `entry_date`
- **Order**: `desc` (newest first)

## User Experience

### Before Fix
- ❌ Clicking column headers did nothing
- ❌ No visual feedback
- ❌ Data remained in default order

### After Fix
- ✅ Clicking column headers sorts the data
- ✅ Arrow icons show current sort direction
- ✅ Data updates immediately
- ✅ Resets to page 1 when sorting changes
- ✅ Loading indicator shows during fetch

## Testing

To test sorting:
1. Navigate to `/admin/data-browser/time-entries`
2. Click any column header with a sort icon
3. Verify data is sorted correctly
4. Click again to reverse sort direction
5. Verify arrow icon changes direction
6. Verify page resets to 1 when sorting

## Files Modified
- `/app/admin/data-browser/time-entries/page.tsx` - Added sort state and handler

## Related Components
- `/components/admin/DataTable.tsx` - Generic table component with sort support
- `/app/api/data/time-entries/route.ts` - API endpoint with sort parameters
