class MainWindow(QMainWindow, Ui_MainWindow):

    def __init__(self, *args, **kwargs):
        super(MainWindow, self).__init__(*args, **kwargs)
        self.setupUi(self)

        self.translator = Translator()

        self.destTextEdit.setReadOnly(True)

        if GOOGLE_TRANSLATE_AVAILABLE:
            self.srcLanguage.addItems(LANGUAGES.keys())
            self.srcLanguage.currentTextChanged[str].connect(self.update_src_language)
            self.srcLanguage.setCurrentText('English')
        else:
            self.srcLanguage.hide()

        self.translateButton.pressed.connect(self.translate)

        self.show()

    def update_src_language(self, l):
        self.language_src = LANGUAGES[l]

    def google_translate(self, text):
        params = dict(
            dest='en',
            text=text
        )

        if self.language_src:
            params['src'] = self.language_src

        try:
            tr = self.translator.translate(**params)

        except Exception:
            self.destTextEdit.setPlainText('Google translate error :(. Try translating from English')
            return False

        else:
            return tr.text       
        
    
    def translate(self):
        # Perform pre-translation to English via Google Translate.
       # if self.language_src != 'en':
        text = self.google_translate(self.srcTextEdit.toPlainText())
        if not text:
            return False
        data = text
        if 'error' in data:
            self.destTextEdit.setPlainText("%s\n\n%s" % (data['error']['message'], text))
        else:
            self.destTextEdit.setPlainText(data)

if __name__ == '__main__':

    app = QApplication([])
    window = MainWindow()
    app.exec_()