# -*- coding: utf-8 -*-
"""
A Translation module.

You can translate text using this module.
"""

import json
import httpx
import random
import typing
import httpcore
from httpx import Timeout
from googletrans import urls, utils
from googletrans.gtoken import TokenAcquirer
from googletrans.constants import (
    DEFAULT_CLIENT_SERVICE_URLS,
    DEFAULT_FALLBACK_SERVICE_URLS,
    DEFAULT_USER_AGENT, LANGCODES, LANGUAGES, SPECIAL_CASES,
    DEFAULT_RAISE_EXCEPTION, DUMMY_DATA
)
from googletrans.models import Translated, Detected, TranslatedPart

EXCLUDES = ('en', 'ca', 'fr')

RPC_ID = 'MkEWBc'


class Translator:
    def __init__(self, service_urls=DEFAULT_CLIENT_SERVICE_URLS, user_agent=DEFAULT_USER_AGENT,
                 raise_exception=DEFAULT_RAISE_EXCEPTION,
                 proxies: typing.Dict[str, httpcore._sync.interfaces.RequestInterface] = None,
                 timeout: Timeout = None,
                 http2=True,
                 use_fallback=False):

        self.client = httpx.Client(http2=http2)
        if proxies is not None:  # pragma: nocover
            self.client.proxies = proxies

        self.client.headers.update({
            'User-Agent': user_agent,
            'Referer': 'https://translate.google.com',
        })

        if timeout is not None:
            self.client.timeout = timeout

        if use_fallback:
            self.service_urls = DEFAULT_FALLBACK_SERVICE_URLS
            self.client_type = 'gtx'
            pass
        else:
            # default way of working: use the defined values from user app
            self.service_urls = service_urls
            self.client_type = 'tw-ob'
            self.token_acquirer = TokenAcquirer(
                client=self.client, host=self.service_urls[0])

        self.raise_exception = raise_exception

    @staticmethod
    def _build_rpc_request(text: str, dest: str, src: str):
        return json.dumps([[
            [
                RPC_ID,
                json.dumps([[text, src, dest, True], [None]], separators=(',', ':')),
                None,
                'generic',
            ],
        ]], separators=(',', ':'))

    def _pick_service_url(self):
        if len(self.service_urls) == 1:
            return self.service_urls[0]
        return random.choice(self.service_urls)

    def _translate(self, text: str, dest: str, src: str):
        url = urls.TRANSLATE_RPC.format(host=self._pick_service_url())
        data = {
            'f.req': self._build_rpc_request(text, dest, src),
        }
        params = {
            'rpcids': RPC_ID,
            'bl': 'boq_translate-webserver_20201207.13_p0',
            'soc-app': 1,
            'soc-platform': 1,
            'soc-device': 1,
            'rt': 'c',
        }
        r = self.client.post(url, params=params, data=data)

        if r.status_code != 200 and self.raise_exception:
            raise Exception('Unexpected status code "{}" from {}'.format(
                r.status_code, self.service_urls))

        return r.text, r

    def _translate_legacy(self, text, dest, src, override):
        token = ''  # dummy default value here as it is not used by api client
        if self.client_type == 'webapp':
            token = self.token_acquirer.do(text)

        params = utils.build_params(client=self.client_type, query=text, src=src, dest=dest,
                                    token=token, override=override)

        url = urls.TRANSLATE.format(host=self._pick_service_url())
        r = self.client.get(url, params=params)

        if r.status_code == 200:
            data = utils.format_json(r.text)
            return data, r

        if self.raise_exception:
            raise Exception('Unexpected status code "{}" from {}'.format(
                r.status_code, self.service_urls))

        DUMMY_DATA[0][0][0] = text
        return DUMMY_DATA, r

    @staticmethod
    def _parse_extra_data(data):
        response_parts_name_mapping = {
            0: 'translation',
            1: 'all-translations',
            2: 'original-language',
            5: 'possible-translations',
            6: 'confidence',
            7: 'possible-mistakes',
            8: 'language',
            11: 'synonyms',
            12: 'definitions',
            13: 'examples',
            14: 'see-also',
        }

        extra = {}

        for index, category in response_parts_name_mapping.items():
            extra[category] = data[index] if (
                index < len(data) and data[index]) else None

        return extra

    def translate(self, text: str, dest='en', src='auto'):
        dest = dest.lower().split('_', 1)[0]
        src = src.lower().split('_', 1)[0]

        if src != 'auto' and src not in LANGUAGES:
            if src in SPECIAL_CASES:
                src = SPECIAL_CASES[src]
            elif src in LANGCODES:
                src = LANGCODES[src]
            else:
                raise ValueError('invalid source language')

        if dest not in LANGUAGES:
            if dest in SPECIAL_CASES:
                dest = SPECIAL_CASES[dest]
            elif dest in LANGCODES:
                dest = LANGCODES[dest]
            else:
                raise ValueError('invalid destination language')

        origin = text
        data, response = self._translate(text, dest, src)

        token_found = False
        square_bracket_counts = [0, 0]
        resp = ''
        for line in data.split('\n'):
            token_found = token_found or f'"{RPC_ID}"' in line[:30]
            if not token_found:
                continue

            is_in_string = False
            for index, char in enumerate(line):
                if char == '\"' and line[max(0, index - 1)] != '\\':
                    is_in_string = not is_in_string
                if not is_in_string:
                    if char == '[':
                        square_bracket_counts[0] += 1
                    elif char == ']':
                        square_bracket_counts[1] += 1

            resp += line
            if square_bracket_counts[0] == square_bracket_counts[1]:
                break

        data = json.loads(resp)
        parsed = json.loads(data[0][2])
        # not sure
        should_spacing = parsed[1][0][0][3]
        translated_parts = list(map(lambda part: TranslatedPart(part[0], part[1] if len(part) >= 2 else []), parsed[1][0][0][5]))
        translated = (' ' if should_spacing else '').join(map(lambda part: part.text, translated_parts))

        if src == 'auto':
            try:
                src = parsed[2]
            except:
                pass
        if src == 'auto':
            try:
                src = parsed[0][2]
            except:
                pass

        # currently not available
        confidence = None

        origin_pronunciation = None
        try:
            origin_pronunciation = parsed[0][0]
        except:
            pass

        pronunciation = None
        try:
            pronunciation = parsed[1][0][0][1]
        except:
            pass

        extra_data = {
            'confidence': confidence,
            'parts': translated_parts,
            'origin_pronunciation': origin_pronunciation,
            'parsed': parsed,
        }
        result = Translated(src=src, dest=dest, origin=origin,
                            text=translated, pronunciation=pronunciation,
                            parts=translated_parts,
                            extra_data=extra_data,
                            response=response)
        return result

    def translate_legacy(self, text, dest='en', src='auto', **kwargs):
        dest = dest.lower().split('_', 1)[0]
        src = src.lower().split('_', 1)[0]

        if src != 'auto' and src not in LANGUAGES:
            if src in SPECIAL_CASES:
                src = SPECIAL_CASES[src]
            elif src in LANGCODES:
                src = LANGCODES[src]
            else:
                raise ValueError('invalid source language')

        if dest not in LANGUAGES:
            if dest in SPECIAL_CASES:
                dest = SPECIAL_CASES[dest]
            elif dest in LANGCODES:
                dest = LANGCODES[dest]
            else:
                raise ValueError('invalid destination language')

        if isinstance(text, list):
            result = []
            for item in text:
                translated = self.translate_legacy(item, dest=dest, src=src, **kwargs)
                result.append(translated)
            return result

        origin = text
        data, response = self._translate_legacy(text, dest, src, kwargs)

        # this code will be updated when the format is changed.
        translated = ''.join([d[0] if d[0] else '' for d in data[0]])

        extra_data = self._parse_extra_data(data)

        # actual source language that will be recognized by Google Translator when the
        # src passed is equal to auto.
        try:
            src = data[2]
        except Exception:  # pragma: nocover
            pass

        pron = origin
        try:
            pron = data[0][1][-2]
        except Exception:  # pragma: nocover
            pass

        if pron is None:
            try:
                pron = data[0][1][2]
            except:  # pragma: nocover
                pass

        if dest in EXCLUDES and pron == origin:
            pron = translated

        # put final values into a new Translated object
        result = Translated(src=src, dest=dest, origin=origin,
                            text=translated, pronunciation=pron,
                            extra_data=extra_data,
                            response=response, parts=None)

        return result

    def detect(self, text: str):
        translated = self.translate(text, src='auto', dest='en')
        result = Detected(lang=translated.src, confidence=translated.extra_data.get('confidence', None), response=translated._response)
        return result

    def detect_legacy(self, text, **kwargs):
        if isinstance(text, list):
            result = []
            for item in text:
                lang = self.detect(item)
                result.append(lang)
            return result

        data, response = self._translate_legacy(text, 'en', 'auto', kwargs)

        # actual source language that will be recognized by Google Translator when the
        # src passed is equal to auto.
        src = ''
        confidence = 0.0
        try:
            if len(data[8][0]) > 1:
                src = data[8][0]
                confidence = data[8][-2]
            else:
                src = ''.join(data[8][0])
                confidence = data[8][-2][0]
        except Exception:  # pragma: nocover
            pass
        result = Detected(lang=src, confidence=confidence, response=response)

        return result