import logging
from typing import Optional

from yaml import safe_load


class I18N:
    def __init__(self, logger: logging.Logger, path="i18n.yaml", fallback_lang="en"):
        self.logger = logger
        self._path = path
        self._fallback_lang = fallback_lang
        self._dict = dict()
        self.load()

    @property
    def path(self):
        return self._path

    @property
    def fallback_lang(self):
        return self._fallback_lang

    def load(self):
        self._dict.clear()
        with open(self._path) as f:
            self._dict = safe_load(f)
        if self.fallback_lang not in self._dict:
            raise RuntimeError("I18N file doesn't contain fallback language section")

    def get(self, phrase: str, lang: Optional[str] = None):
        lang = lang or self.fallback_lang
        if lang not in self._dict:
            self.logger.warning(f"Language '{lang}' not found in i18n, using fallback")
            lang = self.fallback_lang
        lang_dict = self._dict.get(lang)
        result = lang_dict.get(phrase)
        if result is None:
            self.logger.error(f"Phrase '{phrase}' not found in language '{lang}'")
            result = f"<Phrase '{phrase}' not found in language '{lang}'>"
        return result

    def __call__(self, phrase: str, lang: Optional[str] = None, *args, **kwargs):
        return self.get(phrase, lang).format(*args, **kwargs)

    def custom_call(self, lang: Optional[str] = None, *args, **kwargs):
        def call(phrase: str, ilang: Optional[str] = None, *iargs, **ikwargs):
            return self(phrase, lang or ilang, *args, *iargs, **kwargs, **ikwargs)
        return call