package store

import (
	"context"
	"time"
)

// PushSubscription is a browser Web Push endpoint registered by a user.
type PushSubscription struct {
	ID        int64
	UserID    int64
	Endpoint  string
	P256dh    string
	Auth      string
	CreatedAt time.Time
}

// CreatePushSubscription stores a subscription, replacing any previous one
// bound to the same endpoint.
func (s *Store) CreatePushSubscription(ctx context.Context, sub PushSubscription) (*PushSubscription, error) {
	err := s.pool.QueryRow(ctx, `
       INSERT INTO push_subscriptions(user_id, endpoint, p256dh, auth)
       VALUES($1, $2, $3, $4)
       ON CONFLICT (endpoint) DO UPDATE SET user_id = EXCLUDED.user_id, p256dh = EXCLUDED.p256dh, auth = EXCLUDED.auth
       RETURNING id, created_at
   `, sub.UserID, sub.Endpoint, sub.P256dh, sub.Auth).Scan(&sub.ID, &sub.CreatedAt)
	if err != nil {
		return nil, err
	}
	return &sub, nil
}

// DeletePushSubscription removes a subscription by endpoint and owner.
func (s *Store) DeletePushSubscription(ctx context.Context, userID int64, endpoint string) error {
	_, err := s.pool.Exec(ctx, `
       DELETE FROM push_subscriptions WHERE user_id=$1 AND endpoint=$2
   `, userID, endpoint)
	return err
}

// ListPushSubscriptionsForUser returns all endpoints registered by a user.
func (s *Store) ListPushSubscriptionsForUser(ctx context.Context, userID int64) ([]PushSubscription, error) {
	rows, err := s.pool.Query(ctx, `
       SELECT id, user_id, endpoint, p256dh, auth, created_at
       FROM push_subscriptions WHERE user_id=$1
   `, userID)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var subs []PushSubscription
	for rows.Next() {
		var sub PushSubscription
		if err := rows.Scan(&sub.ID, &sub.UserID, &sub.Endpoint, &sub.P256dh, &sub.Auth, &sub.CreatedAt); err != nil {
			return nil, err
		}
		subs = append(subs, sub)
	}
	return subs, nil
}