package db

import (
	"database/sql"
	"fmt"
)

func scanWatchedMount(row interface {
	Scan(dest ...any) error
}) (WatchedMount, error) {
	var m WatchedMount
	var createdAt string
	if err := row.Scan(&m.ID, &m.Path, &createdAt); err != nil {
		return WatchedMount{}, err
	}
	m.CreatedAt = parseTime(createdAt)
	return m, nil
}

func (d *DB) ListWatchedMounts() ([]WatchedMount, error) {
	rows, err := d.conn.Query(`SELECT id, path, created_at FROM watched_mounts ORDER BY path ASC`)
	if err != nil {
		return nil, fmt.Errorf("list watched mounts: %w", err)
	}
	defer rows.Close()

	mounts := make([]WatchedMount, 0)
	for rows.Next() {
		m, err := scanWatchedMount(rows)
		if err != nil {
			return nil, fmt.Errorf("scan watched mount: %w", err)
		}
		mounts = append(mounts, m)
	}
	return mounts, rows.Err()
}

func (d *DB) GetWatchedMount(id int64) (WatchedMount, error) {
	row := d.conn.QueryRow(`SELECT id, path, created_at FROM watched_mounts WHERE id = ?`, id)
	m, err := scanWatchedMount(row)
	if err == sql.ErrNoRows {
		return WatchedMount{}, fmt.Errorf("watched mount not found")
	}
	if err != nil {
		return WatchedMount{}, fmt.Errorf("get watched mount: %w", err)
	}
	return m, nil
}

func (d *DB) CreateWatchedMount(path string) (WatchedMount, error) {
	result, err := d.conn.Exec(
		`INSERT INTO watched_mounts (path) VALUES (?)`,
		path,
	)
	if err != nil {
		return WatchedMount{}, fmt.Errorf("create watched mount: %w", err)
	}
	id, err := result.LastInsertId()
	if err != nil {
		return WatchedMount{}, fmt.Errorf("last insert id: %w", err)
	}
	return d.GetWatchedMount(id)
}

func (d *DB) DeleteWatchedMount(id int64) error {
	result, err := d.conn.Exec(`DELETE FROM watched_mounts WHERE id = ?`, id)
	if err != nil {
		return fmt.Errorf("delete watched mount: %w", err)
	}
	rows, err := result.RowsAffected()
	if err != nil {
		return err
	}
	if rows == 0 {
		return fmt.Errorf("watched mount not found")
	}
	return nil
}

func (d *DB) WatchedMountPathExists(path string) (bool, error) {
	var count int
	err := d.conn.QueryRow(`SELECT COUNT(1) FROM watched_mounts WHERE path = ?`, path).Scan(&count)
	if err != nil {
		return false, err
	}
	return count > 0, nil
}