func didChangeText(range: NSRange, replacementText text: String) {
        let marker = "@"
        var str = ""
        if validInputStarted {
            switch (0) {
            case _ where stringRange.lowerBound <= range.lowerBound && range.lowerBound <= stringRange.upperBound:
                stringRange = stringRange.lowerBound..<stringRange.upperBound + (text.count - range.length)
                str = String(Array(textView.text)[stringRange])
                fallthrough
            case _ where str.range(of: "^[a-z0-9]*(\\.[a-z0-9])*$", options: .regularExpression) != nil: break
            default:
                validInputStarted = false
                clear()
                return
            }
        }
        if !validInputStarted, range.lowerBound + text.count - marker.count >= 0 && text.count > 0 {
            let markerRange = Range(range.lowerBound - marker.count + text.count..<range.lowerBound + text.count)
            if String(Array(textView.text)[markerRange]) == marker {
                stringRange = markerRange.lowerBound + marker.count..<markerRange.upperBound
                validInputStarted = true

                if (self.topConstraint?.isActive ?? true) == false { // show gui
                    UIView.animate(withDuration: 0.3, animations: {
                        self.topConstraint?.isActive = true
                        self.layoutIfNeeded()
                    })
                }
            }
        }

        guard validInputStarted else {
            return
        }

        print(str) // готовая строка

        requestSessionTask?.cancel()

        let searchText = (str as String).addingPercentEncoding(withAllowedCharacters: .urlHostAllowed) ?? ""

        var closuredRequest:URLSessionTask? = nil
        closuredRequest = SearchManager.getAutocompleteWithFollws(searchText, completion: {
            _, result, error in
            if error == nil {
                self.arItems = result
                self.tableView.reloadData()
            }
            if closuredRequest == self.requestSessionTask {
                self.requestSessionTask = nil
            }
        })

        requestSessionTask = closuredRequest
    }


    //MARK: Textview delegate
    private var changedTextRange: NSRange! = nil
    private var replacementText: String! = nil

    func textViewDidChange(_ textView: UITextView) {
        UpdateTextViewSize()
        guard changedTextRange != nil, replacementText != nil else {
            return
        }
        autocomplete.didChangeText(range: changedTextRange, replacementText: replacementText)
        changedTextRange = nil
        replacementText = nil
    }

    func textViewDidChangeSelection(_ textView: UITextView) {
        if changedTextRange == nil {
            autocomplete.didChangeText(range: textView.selectedRange, replacementText: "")
        }
    }

    func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
        let newText = (textView.text as NSString).substring(to: range.location) + text + (textView.text as NSString).substring(from: range.location + range.length)

        if text == "\n" {
            tapOK()
            return false
        }

        if !TextParameters.isValidLengthForFieldType(
            TextFieldType.comment,
            len: newText.count,
            showAlert: true) {
            return false
        }

        changedTextRange = range
        replacementText = text

        return true
    }