// Add a single sentence to the database
func (ns *Nonsentence) addSentence(tx *bolt.Tx, sentence string) error {
	wordsBucket := tx.Bucket([]byte("words"))
	startsBucket := tx.Bucket([]byte("starts"))
	if (wordsBucket == nil) || (startsBucket == nil) {
		return fmt.Errorf("Buckets not found")
	}

	// Split sentence on whitespace
	var words = strings.Fields(sentence)

	if len(words) < 3 {
		// 		log.Printf("Ignoring small sentence: %v", sentence)
		return nil
	}

	// Store words in wordsBucket
	for i := 2; i < len(words); i++ {
		if err := storeWords(wordsBucket, words[i-2], words[i-1], words[i]); err != nil {
			return err
		}
	}
	if err := storeWords(wordsBucket, words[len(words)-2], words[len(words)-1], ""); err != nil {
		return err
	}

	// Store starts in startsBucket
	key := []byte(words[0] + " " + words[1])
	if err := startsBucket.Put(key, []byte{}); err != nil {
		return err
	}

	return nil
}

// Retrieves a key from the database and verifies that it is what is expected.
func simulateGetHandler(tx *bolt.Tx, qdb *QuickDB) {
	// Randomly retrieve an existing exist.
	keys := qdb.Rand()
	if len(keys) == 0 {
		return
	}

	// Retrieve root bucket.
	b := tx.Bucket(keys[0])
	if b == nil {
		panic(fmt.Sprintf("bucket[0] expected: %08x\n", trunc(keys[0], 4)))
	}

	// Drill into nested buckets.
	for _, key := range keys[1 : len(keys)-1] {
		b = b.Bucket(key)
		if b == nil {
			panic(fmt.Sprintf("bucket[n] expected: %v -> %v\n", keys, key))
		}
	}

	// Verify key/value on the final bucket.
	expected := qdb.Get(keys)
	actual := b.Get(keys[len(keys)-1])
	if !bytes.Equal(actual, expected) {
		fmt.Println("=== EXPECTED ===")
		fmt.Println(expected)
		fmt.Println("=== ACTUAL ===")
		fmt.Println(actual)
		fmt.Println("=== END ===")
		panic("value mismatch")
	}
}

//Del deletes one key-value pair.
func Del(tx *bolt.Tx, bucket string, key []byte) error {
	b := tx.Bucket([]byte(bucket))
	if b == nil {
		return errors.New("bucket not found " + bucket)
	}
	return b.Delete(key)
}

func EntrySave(tx *bolt.Tx, entry DbEntry, key string) error {
	godbc.Require(tx != nil)
	godbc.Require(len(key) > 0)

	// Access bucket
	b := tx.Bucket([]byte(entry.BucketName()))
	if b == nil {
		err := errors.New("Unable to access db")
		logger.Err(err)
		return err
	}

	// Save device entry to db
	buffer, err := entry.Marshal()
	if err != nil {
		logger.Err(err)
		return err
	}

	// Save data using the id as the key
	err = b.Put([]byte(key), buffer)
	if err != nil {
		logger.Err(err)
		return err
	}

	return nil
}

// saveRepository saves a repository in the store.
func (s *Store) saveRepository(tx *bolt.Tx, r *internal.Repository) error {
	buf, err := proto.Marshal(r)
	if err != nil {
		return err
	}
	return tx.Bucket([]byte("repositories")).Put([]byte(r.GetID()), buf)
}

// removeFileContract removes a file contract from the database.
func removeFileContract(tx *bolt.Tx, id types.FileContractID) {
	// Delete the file contract entry.
	fcBucket := tx.Bucket(FileContracts)
	fcBytes := fcBucket.Get(id[:])
	// Sanity check - should not be removing a file contract not in the db.
	if build.DEBUG && fcBytes == nil {
		panic("nil file contract")
	}
	err := fcBucket.Delete(id[:])
	if build.DEBUG && err != nil {
		panic(err)
	}

	// Delete the entry for the file contract's expiration. The portion of
	// 'fcBytes' used to determine the expiration bucket id is the
	// byte-representation of the file contract window end, which always
	// appears at bytes 48-56.
	expirationBucketID := append(prefixFCEX, fcBytes[48:56]...)
	expirationBucket := tx.Bucket(expirationBucketID)
	expirationBytes := expirationBucket.Get(id[:])
	if expirationBytes == nil {
		panic(errNilItem)
	}
	err = expirationBucket.Delete(id[:])
	if build.DEBUG && err != nil {
		panic(err)
	}
}

func (m *Manager) persistProvider(tx *bolt.Tx, id string) error {
	// Note: This method does *not* include re-serializing per-volume state,
	// because we assume that hasn't changed unless the change request
	// for the volume came through us and was handled elsewhere already.
	provider, ok := m.providers[id]
	if !ok {
		return tx.Bucket([]byte("providers")).DeleteBucket([]byte(id))
	}
	providersBucket, err := m.getProviderBucket(tx, id)
	if err != nil {
		return fmt.Errorf("could not persist provider info to boltdb: %s", err)
	}
	pspec := &volume.ProviderSpec{}
	pspec.Kind = provider.Kind()
	b, err := provider.MarshalGlobalState()
	if err != nil {
		return fmt.Errorf("failed to serialize provider info: %s", err)
	}
	pspec.Config = b
	b, err = json.Marshal(pspec)
	if err != nil {
		return fmt.Errorf("failed to serialize provider info: %s", err)
	}
	err = providersBucket.Put([]byte("global"), b)
	if err != nil {
		return fmt.Errorf("could not persist provider info to boltdb: %s", err)
	}
	return nil
}

func getReview(tx *bolt.Tx, id int) (review.R, error) {
	var (
		revisions []review.Revision
		review    review.R
	)

	metaData, err := getMetaData(tx)
	if err != nil {
		return review, err
	}

	root := tx.Bucket(rootKey)
	if root == nil {
		return review, ErrNoDB
	}
	reviews := root.Bucket(reviewsKey)
	if reviews == nil {
		return review, ErrNoDB
	}
	reviewBkt, err := getReviewBucket(tx, id)
	if err != nil {
		return review, err
	}
	review.Summary = metaData.Summaries[strconv.Itoa(id)]
	rev := reviewBkt.Get(revisionsKey)
	dec := gob.NewDecoder(bytes.NewReader(rev))
	if err := dec.Decode(&revisions); err != nil {
		return review, err
	}
	review.Revisions = revisions
	return review, nil
}

func SetCounterparty(tx *bolt.Tx, cpt *core.Counterparty) error {
	b, err := json.Marshal(cpt)
	if err != nil {
		return err
	}

	err = tx.Bucket([]byte("Counterparties")).Put([]byte(cpt.Pubkey), b)
	if err != nil {
		return err
	}

	// Relations

	b, err = json.Marshal(cpt.Judge)
	if err != nil {
		return err
	}

	err = tx.Bucket([]byte("Judges")).Put(cpt.Judge.Pubkey, b)
	if err != nil {
		return err
	}

	return nil
}

// removeTriple removes a triple from the indices. If the triple
// contains any terms unique to that triple, they will also be removed.
func (db *DB) removeTriple(tx *bolt.Tx, s, p, o uint32) error {
	// TODO think about what to do if present in one index but
	// not in another: maybe panic? Cause It's a bug that should be fixed.

	indices := []struct {
		k1 uint32
		k2 uint32
		v  uint32
		bk []byte
	}{
		{s, p, o, bucketSPO},
		{o, s, p, bucketOSP},
		{p, o, s, bucketPOS},
	}

	key := make([]byte, 8)
	for _, i := range indices {
		bkt := tx.Bucket(i.bk)
		copy(key, u32tob(i.k1))
		copy(key[4:], u32tob(i.k2))

		bo := bkt.Get(key)
		if bo == nil {
			// TODO should never happen, return bug error?
			return ErrNotFound
		}

		bitmap := roaring.NewBitmap()
		_, err := bitmap.ReadFrom(bytes.NewReader(bo))
		if err != nil {
			return err
		}
		hasTriple := bitmap.CheckedRemove(i.v)
		if !hasTriple {
			// TODO should never happen, return bug error?
			return ErrNotFound
		}
		// Remove from index if bitmap is empty
		if bitmap.GetCardinality() == 0 {
			err = bkt.Delete(key)
			if err != nil {
				return err
			}
		} else {
			var b bytes.Buffer
			_, err = bitmap.WriteTo(&b)
			if err != nil {
				return err
			}
			err = bkt.Put(key, b.Bytes())
			if err != nil {
				return err
			}
		}
	}

	//atomic.AddInt64(&db.numTr, -1)

	return db.removeOrphanedTerms(tx, s, p, o)
}

//line nav.ego:1
func nav(w io.Writer, tx *bolt.Tx) error {
//line nav.ego:2
	if _, err := fmt.Fprintf(w, "\n\n"); err != nil {
		return err
	}
//line nav.ego:4
	if _, err := fmt.Fprintf(w, "\n"); err != nil {
		return err
	}
//line nav.ego:5
	if _, err := fmt.Fprintf(w, "\n\n"); err != nil {
		return err
	}
//line nav.ego:6
	if _, err := fmt.Fprintf(w, "<h1>"); err != nil {
		return err
	}
//line nav.ego:6
	if _, err := fmt.Fprintf(w, "%v", filepath.Base(tx.DB().Path())); err != nil {
		return err
	}
//line nav.ego:6
	if _, err := fmt.Fprintf(w, "</h1>\n"); err != nil {
		return err
	}
	return nil
}

func (db *DB) addTerm(tx *bolt.Tx, term rdf.Term) (id uint32, err error) {
	bt := db.encode(term)

	if id, err = db.getIDb(tx, bt); err == nil {
		// Term is allready in database
		return id, nil
	} else if err != ErrNotFound {
		// Some other IO error occured
		return 0, err
	}

	// get a new ID
	bkt := tx.Bucket(bucketTerms)
	n, err := bkt.NextSequence()
	if err != nil {
		return 0, err
	}
	if n > MaxTerms {
		return 0, ErrDBFull
	}

	id = uint32(n)
	idb := u32tob(uint32(n))

	// store term and index it
	err = bkt.Put(idb, bt)
	if err != nil {
		return 0, err
	}
	bkt = tx.Bucket(bucketIdxTerms)
	err = bkt.Put(bt, idb)
	return id, err
}

func depersistMessage(tx *bolt.Tx, id int64) error {
	content_bucket, err := tx.CreateBucketIfNotExists(MESSAGE_CONTENT_BUCKET)
	if err != nil {
		return err
	}
	return content_bucket.Delete(binaryId(id))
}

// validSiacoins checks that the siacoin inputs and outputs are valid in the
// context of the current consensus set.
func validSiacoins(tx *bolt.Tx, t types.Transaction) error {
	scoBucket := tx.Bucket(SiacoinOutputs)
	var inputSum types.Currency
	for _, sci := range t.SiacoinInputs {
		// Check that the input spends an existing output.
		scoBytes := scoBucket.Get(sci.ParentID[:])
		if scoBytes == nil {
			return errMissingSiacoinOutput
		}

		// Check that the unlock conditions match the required unlock hash.
		var sco types.SiacoinOutput
		err := encoding.Unmarshal(scoBytes, &sco)
		if build.DEBUG && err != nil {
			panic(err)
		}
		if sci.UnlockConditions.UnlockHash() != sco.UnlockHash {
			return errWrongUnlockConditions
		}

		inputSum = inputSum.Add(sco.Value)
	}
	if inputSum.Cmp(t.SiacoinOutputSum()) != 0 {
		return errSiacoinInputOutputMismatch
	}
	return nil
}

// addBlockMap adds a processed block to the block map.
func addBlockMap(tx *bolt.Tx, pb *processedBlock) {
	id := pb.Block.ID()
	err := tx.Bucket(BlockMap).Put(id[:], encoding.Marshal(*pb))
	if build.DEBUG && err != nil {
		panic(err)
	}
}

func SetAccount(tx *bolt.Tx, acct *core.Account) error {
	b, err := json.Marshal(acct)
	if err != nil {
		return err
	}

	err = tx.Bucket([]byte("Accounts")).Put([]byte(acct.Pubkey), b)
	if err != nil {
		return err
	}

	// Relations

	b, err = json.Marshal(acct.Judge)
	if err != nil {
		return err
	}

	err = tx.Bucket([]byte("Judges")).Put(acct.Judge.Pubkey, b)
	if err != nil {
		return err
	}

	return nil
}

// addFileContract adds a file contract to the database. An error is returned
// if the file contract is already in the database.
func addFileContract(tx *bolt.Tx, id types.FileContractID, fc types.FileContract) {
	// Add the file contract to the database.
	fcBucket := tx.Bucket(FileContracts)
	// Sanity check - should not be adding a zero-payout file contract.
	if build.DEBUG && fc.Payout.IsZero() {
		panic("adding zero-payout file contract")
	}
	// Sanity check - should not be adding a file contract already in the db.
	if build.DEBUG && fcBucket.Get(id[:]) != nil {
		panic("repeat file contract")
	}
	err := fcBucket.Put(id[:], encoding.Marshal(fc))
	if build.DEBUG && err != nil {
		panic(err)
	}

	// Add an entry for when the file contract expires.
	expirationBucketID := append(prefixFCEX, encoding.Marshal(fc.WindowEnd)...)
	expirationBucket, err := tx.CreateBucketIfNotExists(expirationBucketID)
	if build.DEBUG && err != nil {
		panic(err)
	}
	err = expirationBucket.Put(id[:], []byte{})
	if build.DEBUG && err != nil {
		panic(err)
	}
}

func SetChannel(tx *bolt.Tx, ch *core.Channel) error {
	b, err := json.Marshal(ch)
	if err != nil {
		return err
	}
	err = tx.Bucket(Channels).Put([]byte(ch.ChannelId), b)
	if err != nil {
		return err
	}

	// Relations

	// Judge

	err = SetJudge(tx, ch.Judge)
	if err != nil {
		return err
	}

	// Accounts

	err = SetAccount(tx, ch.Accounts[0])
	if err != nil {
		return err
	}

	err = SetAccount(tx, ch.Accounts[1])
	if err != nil {
		return err
	}

	return nil
}

// createDSCOBucket creates a bucket for the delayed siacoin outputs at the
// input height.
func createDSCOBucket(tx *bolt.Tx, bh types.BlockHeight) {
	bucketID := append(prefixDSCO, encoding.Marshal(bh)...)
	_, err := tx.CreateBucket(bucketID)
	if build.DEBUG && err != nil {
		panic(err)
	}
}

func GetChannels(tx *bolt.Tx) ([]*core.Channel, error) {
	var err error
	chs := []*core.Channel{}

	err = tx.Bucket(Channels).ForEach(func(k, v []byte) error {
		ch := &core.Channel{}
		err = json.Unmarshal(v, ch)
		if err != nil {
			return err
		}

		err = PopulateChannel(tx, ch)
		if err != nil {
			return errors.New("error populating channel")
		}

		chs = append(chs, ch)

		return nil
	})
	if err != nil {
		return nil, errors.New("database error")
	}
	return chs, nil
}