package common

import (
	"context"
	"database/sql"
	"errors"
	"strings"
	"time"

	cryptotypes "github.com/status-im/status-go/internal/crypto/types"
	types "github.com/status-im/status-go/pkg/messaging/types"
)

type SQLiteMessageConfirmationPersistence struct {
	db *sql.DB
}

var _ MessageConfirmationPersistence = (*SQLiteMessageConfirmationPersistence)(nil)

func NewSQLiteMessageConfirmationPersistence(db *sql.DB) *SQLiteMessageConfirmationPersistence {
	return &SQLiteMessageConfirmationPersistence{db: db}
}

func (p *SQLiteMessageConfirmationPersistence) InsertPendingConfirmation(confirmation *MessageConfirmation) error {
	_, err := p.db.Exec(`INSERT INTO raw_message_confirmations
		 (datasync_id, message_id, public_key)
		 VALUES
		 (?,?,?)`,
		confirmation.DataSyncID,
		confirmation.MessageID,
		confirmation.PublicKey,
	)
	return err
}

// MarkAsConfirmed marks all the messages with dataSyncID as confirmed and returns
// the messageIDs that can be considered confirmed.
// If atLeastOne is set it will return messageid if at least once of the messages
// sent has been confirmed
func (p *SQLiteMessageConfirmationPersistence) MarkAsConfirmed(dataSyncID []byte, atLeastOne bool) (messageID cryptotypes.HexBytes, err error) {
	tx, err := p.db.BeginTx(context.Background(), &sql.TxOptions{})
	if err != nil {
		return nil, err
	}
	defer func() {
		if err == nil {
			err = tx.Commit()
			return
		}
		// don't shadow original error
		_ = tx.Rollback()
	}()

	confirmedAt := time.Now().Unix()
	_, err = tx.Exec(`UPDATE raw_message_confirmations SET confirmed_at = ? WHERE datasync_id = ? AND confirmed_at = 0`, confirmedAt, dataSyncID)
	if err != nil {
		return
	}

	// Select any tuple that has a message_id with a datasync_id = ? and that has just been confirmed
	rows, err := tx.Query(`SELECT message_id,confirmed_at FROM raw_message_confirmations WHERE message_id = (SELECT message_id FROM raw_message_confirmations WHERE datasync_id = ? LIMIT 1)`, dataSyncID)
	if err != nil {
		return
	}
	defer rows.Close()

	confirmedResult := true

	for rows.Next() {
		var confirmedAt int64
		err = rows.Scan(&messageID, &confirmedAt)
		if err != nil {
			return
		}
		confirmed := confirmedAt > 0

		if atLeastOne && confirmed {
			// We return, as at least one was confirmed
			return
		}

		confirmedResult = confirmedResult && confirmed
	}

	if !confirmedResult {
		messageID = nil
		return
	}

	return
}

type SQLiteHashRatchetPersistence struct {
	db *sql.DB
}

func NewSQLiteHashRatchetPersistence(db *sql.DB) *SQLiteHashRatchetPersistence {
	return &SQLiteHashRatchetPersistence{db: db}
}

var _ HashRatchetPersistence = (*SQLiteHashRatchetPersistence)(nil)

func (p *SQLiteHashRatchetPersistence) SaveMessage(groupID []byte, keyID []byte, m *types.ReceivedMessage) error {
	_, err := p.db.Exec(`INSERT INTO hash_ratchet_encrypted_messages(hash, sig, timestamp, topic, payload, dst, padding, group_id, key_id) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)`, m.Hash, m.Sig, m.Timestamp, m.Topic.Bytes(), m.Payload, m.Dst, m.Padding, groupID, keyID)
	return err
}

func (p *SQLiteHashRatchetPersistence) GetMessages(keyID []byte) ([]*types.ReceivedMessage, error) {
	var messages []*types.ReceivedMessage

	rows, err := p.db.Query(`SELECT hash, sig, timestamp, topic, payload, dst, padding FROM hash_ratchet_encrypted_messages WHERE key_id = ?`, keyID)
	if err != nil {
		return nil, err
	}

	for rows.Next() {
		var topic []byte
		message := &types.ReceivedMessage{}

		err := rows.Scan(&message.Hash, &message.Sig, &message.Timestamp, &topic, &message.Payload, &message.Dst, &message.Padding)
		if err != nil {
			return nil, err
		}

		message.Topic = types.BytesToContentTopic(topic)
		messages = append(messages, message)
	}

	return messages, nil
}

func (p *SQLiteHashRatchetPersistence) GetMessagesCountForGroup(groupID []byte) (int, error) {
	var count int
	err := p.db.QueryRow(`SELECT count(*) FROM hash_ratchet_encrypted_messages WHERE group_id = ?`, groupID).Scan(&count)
	if err == nil {
		return count, nil
	}
	if errors.Is(err, sql.ErrNoRows) {
		return 0, nil
	}
	return 0, err
}

func (p *SQLiteHashRatchetPersistence) DeleteMessages(ids [][]byte) error {
	if len(ids) == 0 {
		return nil
	}

	idsArgs := make([]interface{}, 0, len(ids))
	for _, id := range ids {
		idsArgs = append(idsArgs, id)
	}
	inVector := strings.Repeat("?, ", len(ids)-1) + "?"

	_, err := p.db.Exec("DELETE FROM hash_ratchet_encrypted_messages WHERE hash IN ("+inVector+")", idsArgs...) // nolint: gosec

	return err
}

func (p *SQLiteHashRatchetPersistence) DeleteMessagesOlderThan(timestamp int64) error {
	_, err := p.db.Exec("DELETE FROM hash_ratchet_encrypted_messages WHERE timestamp < ?", timestamp)
	return err
}