package store

import (
	"context"
	"database/sql"
	"fmt"
	"time"
)

type Locks struct {
	DB         *sql.DB
	TTLMinutes int
}

func (s *Locks) Acquire(ctx context.Context, hostID, operationID int64) error {
	s.cleanExpired(ctx)
	expiresAt := time.Now().UTC().Add(time.Duration(s.TTLMinutes) * time.Minute).Format(time.RFC3339)
	_, err := s.DB.ExecContext(ctx, `
		INSERT INTO operation_locks(host_id, operation_id, expires_at)
		VALUES(?,?,?)
	`, hostID, operationID, expiresAt)
	if err != nil {
		return fmt.Errorf("acquire lock: %w", err)
	}
	return nil
}

func (s *Locks) Release(ctx context.Context, hostID int64) error {
	_, err := s.DB.ExecContext(ctx, `DELETE FROM operation_locks WHERE host_id = ?`, hostID)
	return err
}

func (s *Locks) IsLocked(ctx context.Context, hostID int64) (bool, error) {
	s.cleanExpired(ctx)
	var count int
	err := s.DB.QueryRowContext(ctx, `SELECT COUNT(1) FROM operation_locks WHERE host_id = ?`, hostID).Scan(&count)
	if err != nil {
		return false, fmt.Errorf("check lock: %w", err)
	}
	return count > 0, nil
}

func (s *Locks) cleanExpired(ctx context.Context) {
	now := time.Now().UTC().Format(time.RFC3339)
	_, _ = s.DB.ExecContext(ctx, `DELETE FROM operation_locks WHERE expires_at < ?`, now)
}