# Copyright 2017 Mycroft AI Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
from gtts import gTTS
from gtts.lang import tts_langs

from .tts import TTS, TTSValidator

from mycroft.util.log import LOG

# Live list of languages
# Cached list of supported languages (2021-02-09)
_default_langs = {
    "af": "Afrikaans",
    "sq": "Albanian",
    "ar": "Arabic",
    "hy": "Armenian",
    "bn": "Bengali",
    "bs": "Bosnian",
    "ca": "Catalan",
    "hr": "Croatian",
    "cs": "Czech",
    "da": "Danish",
    "nl": "Dutch",
    "en": "English",
    "eo": "Esperanto",
    "et": "Estonian",
    "tl": "Filipino",
    "fi": "Finnish",
    "fr": "French",
    "de": "German",
    "el": "Greek",
    "gu": "Gujarati",
    "hi": "Hindi",
    "hu": "Hungarian",
    "is": "Icelandic",
    "id": "Indonesian",
    "it": "Italian",
    "ja": "Japanese",
    "jw": "Javanese",
    "kn": "Kannada",
    "km": "Khmer",
    "ko": "Korean",
    "la": "Latin",
    "lv": "Latvian",
    "mk": "Macedonian",
    "ml": "Malayalam",
    "mr": "Marathi",
    "my": "Myanmar (Burmese)",
    "ne": "Nepali",
    "no": "Norwegian",
    "pl": "Polish",
    "pt": "Portuguese",
    "ro": "Romanian",
    "ru": "Russian",
    "sr": "Serbian",
    "si": "Sinhala",
    "sk": "Slovak",
    "es": "Spanish",
    "su": "Sundanese",
    "sw": "Swahili",
    "sv": "Swedish",
    "ta": "Tamil",
    "te": "Telugu",
    "th": "Thai",
    "tr": "Turkish",
    "uk": "Ukrainian",
    "ur": "Urdu",
    "vi": "Vietnamese",
    "cy": "Welsh",
    "zh": "Chinese (Mandarin/China)",
}


_supported_langs = None


def get_supported_langs():
    """Get dict of supported languages.

    Tries to fetch remote list, if that fails a local cache will be used.

    Returns:
        (dict): Lang code to lang name map.
    """
    global _supported_langs
    if not _supported_langs:
        try:
            _supported_langs = tts_langs()
        except Exception:
            LOG.warning("Couldn't fetch upto date language codes")
    return _supported_langs or _default_langs


class GoogleTTS(TTS):
    """Interface to google TTS."""

    def __init__(self, lang, config):
        self._google_lang = None
        super(GoogleTTS, self).__init__(lang, config, GoogleTTSValidator(self), "mp3")

    @property
    def google_lang(self):
        """Property containing a converted language code suitable for gTTS."""
        supported_langs = get_supported_langs()
        if not self._google_lang:
            if self.lang.lower() in supported_langs:
                self._google_lang = self.lang.lower()
            elif self.lang[:2].lower() in supported_langs:
                self._google_lang = self.lang[:2]
        return self._google_lang or self.lang.lower()

    def get_tts(self, sentence, wav_file):
        """Fetch tts audio using gTTS.

        Args:
            sentence (str): Sentence to generate audio for
            wav_file (str): output file path
        Returns:
            Tuple ((str) written file, None)
        """
        tts = gTTS(text=sentence, lang=self.google_lang)
        tts.save(wav_file)
        return (wav_file, None)  # No phonemes


class GoogleTTSValidator(TTSValidator):
    def __init__(self, tts):
        super(GoogleTTSValidator, self).__init__(tts)

    def validate_lang(self):
        lang = self.tts.google_lang
        if lang.lower() not in get_supported_langs():
            raise ValueError("Language not supported by gTTS: {}".format(lang))

    def validate_connection(self):
        try:
            gTTS(text="Hi").save(self.tts.filename)
        except Exception:
            raise Exception(
                "GoogleTTS server could not be verified. Please check your "
                "internet connection."
            )

    def get_tts_class(self):
        return GoogleTTS