# Feature: Reports

## Views
| View    | Period        | Grouping              |
|---------|---------------|-----------------------|
| Daily   | Selected day  | Per entry (list)      |
| Weekly  | Mon–Sun       | Per day (bar chart)   |
| Monthly | Calendar month| Per week (bar chart)  |

## Chart Data Format (fl_chart BarChart)
```dart
// Weekly: 7 bars (Mon=0 … Sun=6)
List<BarChartGroupData> weeklyBars(Map<int, Duration> durationByWeekday) {
  return List.generate(7, (i) => BarChartGroupData(
    x: i,
    barRods: [BarChartRodData(toY: durationByWeekday[i]?.inMinutes.toDouble() ?? 0)],
  ));
}
```

## Key Queries (Drift)
```dart
// Total duration per project in date range
SELECT project_id, SUM(duration_s) AS total
FROM time_entries
WHERE start_time >= :from AND start_time < :to
  AND end_time IS NOT NULL
GROUP BY project_id;

// Duration per weekday in week
SELECT strftime('%w', start_time) AS weekday, SUM(duration_s) AS total
FROM time_entries
WHERE start_time >= :weekStart AND start_time < :weekEnd
  AND end_time IS NOT NULL
GROUP BY weekday;
```

## ReportsNotifier
- Exposes `selectedPeriod` (day/week/month) and `selectedDate`
- Provides `AsyncValue<ReportData>` via Drift watch stream
- `ReportData` contains: total duration, per-project breakdown, chart bars

## Filters
- Filter by project (optional, default: all projects)
- Filter by tag (optional)
- Date navigation: previous/next period buttons

## Summary Cards
Each report view shows:
- Total tracked time for period
- Most tracked project
- Average daily hours (weekly/monthly view)