package queries

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

func (q *Queries) DBTX() DBTX {
	return q.db
}

func (q *Queries) InTx(
	ctx context.Context,
	opts *sql.TxOptions,
	body func(context.Context, *Queries) error,
) error {
	var tx *sql.Tx
	var err error

	switch db := q.db.(type) {
	case *sql.Tx:
		return body(ctx, q)
	case interface {
		BeginTx(context.Context, *sql.TxOptions) (*sql.Tx, error)
	}:
		tx, err = db.BeginTx(ctx, opts)
		if err != nil {
			return fmt.Errorf("Queries.InTx failed to create tx: %w", err)
		}
		defer func() {
			if err == nil {
				_ = tx.Commit()
			} else {
				_ = tx.Rollback()
			}
		}()
		err = body(ctx, New(tx))
		return err
	default:
		return errors.New("Queries.InTx: invalid DBTX type")
	}
}