package storm

import "github.com/coreos/bbolt"

// CreateBucketIfNotExists creates the bucket below the current node if it doesn't
// already exist.
func (n *node) CreateBucketIfNotExists(tx *bolt.Tx, bucket string) (*bolt.Bucket, error) {
	var b *bolt.Bucket
	var err error

	bucketNames := append(n.rootBucket, bucket)

	for _, bucketName := range bucketNames {
		if b != nil {
			if b, err = b.CreateBucketIfNotExists([]byte(bucketName)); err != nil {
				return nil, err
			}

		} else {
			if b, err = tx.CreateBucketIfNotExists([]byte(bucketName)); err != nil {
				return nil, err
			}
		}
	}

	return b, nil
}

// GetBucket returns the given bucket below the current node.
func (n *node) GetBucket(tx *bolt.Tx, children ...string) *bolt.Bucket {
	var b *bolt.Bucket

	bucketNames := append(n.rootBucket, children...)
	for _, bucketName := range bucketNames {
		if b != nil {
			if b = b.Bucket([]byte(bucketName)); b == nil {
				return nil
			}
		} else {
			if b = tx.Bucket([]byte(bucketName)); b == nil {
				return nil
			}
		}
	}

	return b
}