package storage

import "context"

type BookingDay struct {
	Date      string  `json:"date"`
	DoctorIDs []int64 `json:"doctor_ids"`
}

// PublicBookingDays returns only dates and public doctor IDs, never patient data.
// Keep the occupancy rules identical to FreeOnecSlots, including cross-branch reservations.
func (s *Storage) PublicBookingDays(ctx context.Context) ([]BookingDay, error) {
	rows, err := s.pool.Query(ctx, `
		SELECT to_char(sl.start_at AT TIME ZONE 'Europe/Moscow','YYYY-MM-DD'),
		       array_agg(DISTINCT d.id ORDER BY d.id)
		FROM onec_slots sl JOIN onec_doctors od ON od.onec_id=sl.doctor_onec_id
		JOIN doctors d ON d.id=od.doctor_id
		WHERE sl.status='free' AND sl.start_at>now() AND od.active
		  AND d.published AND d.deleted_at IS NULL AND NOT d.absent AND d.booking_provider='native'
		  AND NOT EXISTS(SELECT 1 FROM onec_appointments a
		    WHERE a.doctor_onec_id=sl.doctor_onec_id AND a.status IN('pending','booked','arrived')
		    AND a.start_at<sl.end_at AND COALESCE(a.end_at,a.start_at+interval '30 minutes')>sl.start_at)
		GROUP BY 1 ORDER BY 1`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	out := []BookingDay{}
	for rows.Next() {
		var day BookingDay
		if err := rows.Scan(&day.Date, &day.DoctorIDs); err != nil {
			return nil, err
		}
		out = append(out, day)
	}
	return out, rows.Err()
}