"""Language related functionality."""
from __future__ import annotations

import json
import os
from typing import TYPE_CHECKING

import _ba

if TYPE_CHECKING:
    from typing import Any, Dict, List, Optional


class Lstr:
    """Used to specify strings in a language-independent way.

    category: General Utility Classes

    These should be used whenever possible in place of hard-coded strings
    so that in-game or UI elements show up correctly on all clients in their
    currently-active language.

    To see available resource keys, look at any of the bs_language_*.py files
    in the game or the translations pages at bombsquadgame.com/translate.

    # EXAMPLE 1: specify a string from a resource path
    mynode.text = ba.Lstr(resource='audioSettingsWindow.titleText')

    # EXAMPLE 2: specify a translated string via a category and english value;
    # if a translated value is available, it will be used; otherwise the
    # english value will be. To see available translation categories, look
    # under the 'translations' resource section.
    mynode.text = ba.Lstr(translate=('gameDescriptions', 'Defeat all enemies'))

    # EXAMPLE 3: specify a raw value and some substitutions.  Substitutions can
    # be used with resource and translate modes as well.
    mynode.text = ba.Lstr(value='${A} / ${B}',
                          subs=[('${A}', str(score)), ('${B}', str(total))])

    # EXAMPLE 4: Lstrs can be nested.  This example would display the resource
    # at res_a but replace ${NAME} with the value of the resource at res_b
    mytextnode.text = ba.Lstr(resource='res_a',
                              subs=[('${NAME}', ba.Lstr(resource='res_b'))])
    """

    def __init__(self, *args: Any, **keywds: Any) -> None:
        """Instantiate a Lstr.

        Pass a value for either 'resource', 'translate',
        or 'value'. (see Lstr help for examples).
        'subs' can be a sequence of 2-member sequences consisting of values
        and replacements.
        'fallback_resource' can be a resource key that will be used if the
        main one is not present for
        the current language in place of falling back to the english value
        ('resource' mode only).
        'fallback_value' can be a literal string that will be used if neither
        the resource nor the fallback resource is found ('resource' mode only).
        """
        # pylint: disable=too-many-branches
        if args:
            raise Exception('Lstr accepts only keyword arguments')

        # Basically just store the exact args they passed.
        # However if they passed any Lstr values for subs,
        # replace them with that Lstr's dict.
        self.args = keywds
        our_type = type(self)

        if isinstance(self.args.get('value'), our_type):
            raise Exception("'value' must be a regular string; not an Lstr")

        if 'subs' in self.args:
            subs_new = []
            for key, value in keywds['subs']:
                if isinstance(value, our_type):
                    subs_new.append((key, value.args))
                else:
                    subs_new.append((key, value))
            self.args['subs'] = subs_new

        # As of protocol 31 we support compact key names
        # ('t' instead of 'translate', etc). Convert as needed.
        if 'translate' in keywds:
            keywds['t'] = keywds['translate']
            del keywds['translate']
        if 'resource' in keywds:
            keywds['r'] = keywds['resource']
            del keywds['resource']
        if 'value' in keywds:
            keywds['v'] = keywds['value']
            del keywds['value']
        if 'fallback' in keywds:
            from ba import _error
            _error.print_error(
                'deprecated "fallback" arg passed to Lstr(); use '
                'either "fallback_resource" or "fallback_value"',
                once=True)
            keywds['f'] = keywds['fallback']
            del keywds['fallback']
        if 'fallback_resource' in keywds:
            keywds['f'] = keywds['fallback_resource']
            del keywds['fallback_resource']
        if 'subs' in keywds:
            keywds['s'] = keywds['subs']
            del keywds['subs']
        if 'fallback_value' in keywds:
            keywds['fv'] = keywds['fallback_value']
            del keywds['fallback_value']

    def evaluate(self) -> str:
        """Evaluate the Lstr and returns a flat string in the current language.

        You should avoid doing this as much as possible and instead pass
        and store Lstr values.
        """
        return _ba.evaluate_lstr(self._get_json())

    def is_flat_value(self) -> bool:
        """Return whether the Lstr is a 'flat' value.

        This is defined as a simple string value incorporating no translations,
        resources, or substitutions.  In this case it may be reasonable to
        replace it with a raw string value, perform string manipulation on it,
        etc.
        """
        return bool('v' in self.args and not self.args.get('s', []))

    def _get_json(self) -> str:
        try:
            return json.dumps(self.args, separators=(',', ':'))
        except Exception:
            from ba import _error
            _error.print_exception('_get_json failed for', self.args)
            return 'JSON_ERR'

    def __str__(self) -> str:
        return '<ba.Lstr: ' + self._get_json() + '>'

    def __repr__(self) -> str:
        return '<ba.Lstr: ' + self._get_json() + '>'


def setlanguage(language: Optional[str],
                print_change: bool = True,
                store_to_config: bool = True) -> None:
    """Set the active language used for the game.

    category: General Utility Functions

    Pass None to use OS default language.
    """
    # pylint: disable=too-many-locals
    # pylint: disable=too-many-branches
    cfg = _ba.app.config
    cur_language = cfg.get('Lang', None)

    # Store this in the config if its changing.
    if language != cur_language and store_to_config:
        if language is None:
            if 'Lang' in cfg:
                del cfg['Lang']  # Clear it out for default.
        else:
            cfg['Lang'] = language
        cfg.commit()
        switched = True
    else:
        switched = False

    with open('data/data/languages/english.json') as infile:
        lenglishvalues = json.loads(infile.read())

    # None implies default.
    if language is None:
        language = _ba.app.default_language
    try:
        if language == 'English':
            lmodvalues = None
        else:
            lmodfile = 'data/data/languages/' + language.lower() + '.json'
            with open(lmodfile) as infile:
                lmodvalues = json.loads(infile.read())
    except Exception:
        from ba import _error
        _error.print_exception('Exception importing language:', language)
        _ba.screenmessage("Error setting language to '" + language +
                          "'; see log for details",
                          color=(1, 0, 0))
        switched = False
        lmodvalues = None

    # Create an attrdict of *just* our target language.
    _ba.app.language_target = AttrDict()
    langtarget = _ba.app.language_target
    assert langtarget is not None
    _add_to_attr_dict(langtarget,
                      lmodvalues if lmodvalues is not None else lenglishvalues)

    # Create an attrdict of our target language overlaid on our base (english).
    languages = [lenglishvalues]
    if lmodvalues is not None:
        languages.append(lmodvalues)
    lfull = AttrDict()
    for lmod in languages:
        _add_to_attr_dict(lfull, lmod)
    _ba.app.language_merged = lfull

    # Pass some keys/values in for low level code to use;
    # start with everything in their 'internal' section.
    internal_vals = [
        v for v in list(lfull['internal'].items()) if isinstance(v[1], str)
    ]

    # Cherry-pick various other values to include.
    # (should probably get rid of the 'internal' section
    # and do everything this way)
    for value in [
            'replayNameDefaultText', 'replayWriteErrorText',
            'replayVersionErrorText', 'replayReadErrorText'
    ]:
        internal_vals.append((value, lfull[value]))
    internal_vals.append(
        ('axisText', lfull['configGamepadWindow']['axisText']))
    lmerged = _ba.app.language_merged
    assert lmerged is not None
    random_names = [
        n.strip() for n in lmerged['randomPlayerNamesText'].split(',')
    ]
    random_names = [n for n in random_names if n != '']
    _ba.set_internal_language_keys(internal_vals, random_names)
    if switched and print_change:
        _ba.screenmessage(Lstr(resource='languageSetText',
                               subs=[('${LANGUAGE}',
                                      Lstr(translate=('languages', language)))
                                     ]),
                          color=(0, 1, 0))


def _add_to_attr_dict(dst: AttrDict, src: Dict) -> None:
    for key, value in list(src.items()):
        if isinstance(value, dict):
            try:
                dst_dict = dst[key]
            except Exception:
                dst_dict = dst[key] = AttrDict()
            if not isinstance(dst_dict, AttrDict):
                raise Exception("language key '" + key +
                                "' is defined both as a dict and value")
            _add_to_attr_dict(dst_dict, value)
        else:
            if not isinstance(value, (float, int, bool, str, str, type(None))):
                raise Exception("invalid value type for res '" + key + "': " +
                                str(type(value)))
            dst[key] = value


class AttrDict(dict):
    """A dict that can be accessed with dot notation.

    (so foo.bar is equivalent to foo['bar'])
    """

    def __getattr__(self, attr: str) -> Any:
        val = self[attr]
        assert not isinstance(val, bytes)
        return val

    def __setattr__(self, attr: str, value: Any) -> None:
        raise Exception()


def get_resource(resource: str,
                 fallback_resource: str = None,
                 fallback_value: Any = None) -> Any:
    """Return a translation resource by name."""
    try:
        # If we have no language set, go ahead and set it.
        if _ba.app.language_merged is None:
            language = _ba.app.language
            try:
                setlanguage(language,
                            print_change=False,
                            store_to_config=False)
            except Exception:
                from ba import _error
                _error.print_exception('exception setting language to',
                                       language)

                # Try english as a fallback.
                if language != 'English':
                    print('Resorting to fallback language (English)')
                    try:
                        setlanguage('English',
                                    print_change=False,
                                    store_to_config=False)
                    except Exception:
                        _error.print_exception(
                            'error setting language to english fallback')

        # If they provided a fallback_resource value, try the
        # target-language-only dict first and then fall back to trying the
        # fallback_resource value in the merged dict.
        if fallback_resource is not None:
            try:
                values = _ba.app.language_target
                splits = resource.split('.')
                dicts = splits[:-1]
                key = splits[-1]
                for dct in dicts:
                    assert values is not None
                    values = values[dct]
                assert values is not None
                val = values[key]
                return val
            except Exception:
                # FIXME: Shouldn't we try the fallback resource in the merged
                #  dict AFTER we try the main resource in the merged dict?
                try:
                    values = _ba.app.language_merged
                    splits = fallback_resource.split('.')
                    dicts = splits[:-1]
                    key = splits[-1]
                    for dct in dicts:
                        assert values is not None
                        values = values[dct]
                    assert values is not None
                    val = values[key]
                    return val

                except Exception:
                    # If we got nothing for fallback_resource, default to the
                    # normal code which checks or primary value in the merge
                    # dict; there's a chance we can get an english value for
                    # it (which we weren't looking for the first time through).
                    pass

        values = _ba.app.language_merged
        splits = resource.split('.')
        dicts = splits[:-1]
        key = splits[-1]
        for dct in dicts:
            assert values is not None
            values = values[dct]
        assert values is not None
        val = values[key]
        return val

    except Exception:
        # Ok, looks like we couldn't find our main or fallback resource
        # anywhere. Now if we've been given a fallback value, return it;
        # otherwise fail.
        if fallback_value is not None:
            return fallback_value
        raise Exception("resource not found: '" + resource + "'")


def translate(category: str,
              strval: str,
              raise_exceptions: bool = False,
              print_errors: bool = False) -> str:
    """Translate a value (or return the value if no translation available)

    Generally you should use ba.Lstr which handles dynamic translation,
    as opposed to this which returns a flat string.
    """
    try:
        translated = get_resource('translations')[category][strval]
    except Exception as exc:
        if raise_exceptions:
            raise
        if print_errors:
            print(('Translate error: category=\'' + category + '\' name=\'' +
                   strval + '\' exc=' + str(exc) + ''))
        translated = None
    translated_out: str
    if translated is None:
        translated_out = strval
    else:
        translated_out = translated
    assert isinstance(translated_out, str)
    return translated_out


def get_valid_languages() -> List[str]:
    """Return a list containing names of all available languages.

    category: General Utility Functions

    Languages that may be present but are not displayable on the running
    version of the game are ignored.
    """
    langs = set()
    app = _ba.app
    try:
        names = os.listdir('data/data/languages')
        names = [n.replace('.json', '').capitalize() for n in names]
    except Exception:
        from ba import _error
        _error.print_exception()
        names = []
    for name in names:
        if app.can_display_language(name):
            langs.add(name)
    return sorted(name for name in names if app.can_display_language(name))


def is_custom_unicode_char(char: str) -> bool:
    """Return whether a char is in the custom unicode range we use."""
    if not isinstance(char, str) or len(char) != 1:
        raise Exception("Invalid Input; not unicode or not length 1")
    return 0xE000 <= ord(char) <= 0xF8FF