from translate import Translator

from edmond.plugin import Plugin


class TranslatePlugin(Plugin):
    """Translate text using the `translate` package.

    The translate package can use a bunch of translation interfaces but the
    default is MyMemory which is fine for our purposes. There are two ways to
    ask for a translation:
    - Without any additional params, the source language is autodetected and
      the target language is specified in the config file;
    - With BOTH source and target languages.
    """

    REQUIRED_CONFIGS = [
        "commands",
        "default_dest",
        "param_source",
        "param_dest",
    ]

    def __init__(self, bot):
        super().__init__(bot)

    def on_pubmsg(self, event):
        if not self.should_handle_command(event.arguments[0]):
            return False

        text = self.command.content
        if not text:
            self.signal_failure(event.target)
            return True
        words = text.split()
        if len(words) == 0:
            self.signal_failure(event.target)
            return True

        from_lang, to_lang, text = self.parse_words(words)
        self.bot.log_d(f"Translating '{text}' from {from_lang} to {to_lang}.")
        translator = Translator(to_lang=to_lang, from_lang=from_lang)
        translation = translator.translate(text)
        self.bot.say(event.target, translation)
        return True

    def parse_words(self, words):
        """Parse given words for parameters and return (from, to, text)."""
        # If no language specification is found, use default params.
        if (
            len(words) < 5
            or words[0] != self.config["param_source"]
            or words[2] != self.config["param_dest"]
        ):
            return "autodetect", self.config["default_dest"], " ".join(words)
        # Else use the parameters provided.
        return words[1], words[3], " ".join(words[4:])