package importer

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

	"github.com/jackc/pgx/v5"
)

// LatestID returns the maximum id in the replica table.
func LatestID(ctx context.Context, conn *pgx.Conn, schema, table string) (int64, error) {
	var id sql.NullInt64
	query := fmt.Sprintf("SELECT MAX(id) FROM %s", pgx.Identifier{schema, table}.Sanitize())
	if err := conn.QueryRow(ctx, query).Scan(&id); err != nil {
		return 0, err
	}
	if !id.Valid {
		return 0, nil
	}
	return id.Int64, nil
}

// CountUpToID returns the number of rows with id <= maxID.
func CountUpToID(ctx context.Context, conn *pgx.Conn, schema, table string, maxID int64) (int64, error) {
	var count sql.NullInt64
	query := fmt.Sprintf("SELECT COUNT(*) FROM %s WHERE id <= $1", pgx.Identifier{schema, table}.Sanitize())
	if err := conn.QueryRow(ctx, query, maxID).Scan(&count); err != nil {
		return 0, err
	}
	if !count.Valid {
		return 0, nil
	}
	return count.Int64, nil
}