package orm

import (
	"context"
	"database/sql"

	"github.com/jinzhu/gorm"
	"github.com/pkg/errors"
)

func WithTx(ctx context.Context, db *gorm.DB, fn func(context.Context, *gorm.DB) error) error {
	tx := db.BeginTx(ctx, &sql.TxOptions{})

	defer func() {
		if err := tx.Rollback().Error; err != nil && !isGormError(err, gorm.ErrInvalidTransaction) {
			panic(errors.Wrap(err, "could not rollback transaction"))
		}
	}()

	if err := fn(ctx, tx); err != nil {
		err := errors.Wrap(err, "could not apply down migration")

		if rollbackErr := tx.Rollback().Error; rollbackErr != nil {
			return errors.Wrap(err, rollbackErr.Error())
		}

		return err
	}

	if err := tx.Commit().Error; err != nil {
		return errors.Wrap(err, "could not commit transaction")
	}

	return nil
}

func isGormError(err error, compErr error) bool {
	if errs, ok := err.(gorm.Errors); ok {
		for _, err := range errs {
			if errors.Is(err, compErr) {
				return true
			}
		}
	}

	return errors.Is(err, compErr)
}