epicyon/languages.py

__filename__ = "languages.py"
__author__ = "Bob Mottram"
__license__ = "AGPL3+"
__version__ = "1.2.0"
__maintainer__ = "Bob Mottram"
__email__ = "bob@freedombone.net"
__status__ = "Production"
__module_group__ = "Core"

import os
import json
from urllib import request, parse
from utils import getActorLanguagesList
from utils import removeHtml
from utils import hasObjectDict
from utils import getConfigParam
from cache import getPersonFromCache


def getActorLanguages(actorJson: {}) -> str:
    """Returns a string containing languages used by the given actor
    """
    langList = getActorLanguagesList(actorJson)
    if not langList:
        return ''
    languagesStr = ''
    for lang in langList:
        if languagesStr:
            languagesStr += ' / ' + lang
        else:
            languagesStr = lang
    return languagesStr


def setActorLanguages(baseDir: str, actorJson: {}, languagesStr: str) -> None:
    """Sets the languages used by the given actor
    """
    separator = ','
    if '/' in languagesStr:
        separator = '/'
    elif ';' in languagesStr:
        separator = ';'
    langList = languagesStr.lower().split(separator)
    langList2 = []
    for lang in langList:
        lang = lang.strip()
        if baseDir:
            languageFilename = baseDir + '/translations/' + lang + '.json'
            if os.path.isfile(languageFilename):
                langList2.append(lang)
        else:
            langList2.append(lang)

    # remove any existing value
    propertyFound = None
    for propertyValue in actorJson['attachment']:
        if not propertyValue.get('name'):
            continue
        if not propertyValue.get('type'):
            continue
        if not propertyValue['name'].lower().startswith('languages'):
            continue
        propertyFound = propertyValue
        break
    if propertyFound:
        actorJson['attachment'].remove(propertyFound)

    if not langList2:
        return

    newLanguages = {
        "name": "Languages",
        "type": "PropertyValue",
        "value": langList2
    }
    actorJson['attachment'].append(newLanguages)


def understoodPostLanguage(baseDir: str, nickname: str, domain: str,
                           messageJson: {}, systemLanguage: str,
                           httpPrefix: str, domainFull: str,
                           personCache: {}) -> bool:
    """Returns true if the post is written in a language
    understood by this account
    """
    msgObject = messageJson
    if hasObjectDict(messageJson):
        msgObject = messageJson['object']
    if not msgObject.get('contentMap'):
        return True
    if not isinstance(msgObject['contentMap'], dict):
        return True
    if msgObject['contentMap'].get(systemLanguage):
        return True
    personUrl = httpPrefix + '://' + domainFull + '/users/' + nickname
    actorJson = getPersonFromCache(baseDir, personUrl, personCache, False)
    if not actorJson:
        print('WARN: unable to load actor to check languages ' + personUrl)
        return False
    languagesUnderstood = getActorLanguagesList(actorJson)
    if not languagesUnderstood:
        return True
    for lang in languagesUnderstood:
        if msgObject['contentMap'].get(lang):
            return True
    # is the language for this post supported by libretranslate?
    libretranslateUrl = getConfigParam(baseDir, "libretranslateUrl")
    if libretranslateUrl:
        libretranslateApiKey = getConfigParam(baseDir, "libretranslateApiKey")
        langList = \
            _libretranslateLanguages(libretranslateUrl, libretranslateApiKey)
        for lang in langList:
            if msgObject['contentMap'].get(lang):
                return True
    return False


def _libretranslateLanguages(url: str, apiKey: str = None) -> []:
    """Returns a list of supported languages
    """
    if not url.endswith('/languages'):
        if not url.endswith('/'):
            url += "/languages"
        else:
            url += "languages"

    params = dict()

    if apiKey:
        params["api_key"] = apiKey

    urlParams = parse.urlencode(params)

    req = request.Request(url, data=urlParams.encode())

    response = request.urlopen(req)

    response_str = response.read().decode()

    result = json.loads(response_str)
    if not result:
        return []
    if not isinstance(result, list):
        return []

    langList = []
    for lang in result:
        if not isinstance(lang, dict):
            continue
        if not lang.get('code'):
            continue
        langCode = lang['code']
        if len(langCode) != 2:
            continue
        langList.append(langCode)
    langList.sort()
    return langList


def getLinksFromContent(content: str) -> {}:
    """Returns a list of links within the given content
    """
    if '<a href' not in content:
        return {}
    sections = content.split('<a href')
    first = True
    links = {}
    for subsection in sections:
        if first:
            first = False
            continue
        if '"' not in subsection:
            continue
        url = subsection.split('"')[1].strip()
        if '://' in url and '.' in url and \
           '>' in subsection:
            if url not in links:
                linkText = subsection.split('>')[1]
                if '<' in linkText:
                    linkText = linkText.split('<')[0]
                    links[linkText] = url
    return links


def addLinksToContent(content: str, links: {}) -> str:
    """Adds links back into plain text
    """
    for linkText, url in links.items():
        urlDesc = url
        if linkText.startswith('@') and linkText in content:
            content = \
                content.replace(linkText,
                                '<a href="' + url +
                                '" rel="nofollow noopener ' +
                                'noreferrer" target="_blank">' +
                                linkText + '</a>')
        else:
            if len(urlDesc) > 40:
                urlDesc = urlDesc[:40]
            content += \
                '<p><a href="' + url + \
                '" rel="nofollow noopener noreferrer" target="_blank">' + \
                urlDesc + '</a></p>'
    return content


def _libretranslate(url: str, text: str,
                    source: str, target: str, apiKey: str = None) -> str:
    """Translate string using libretranslate
    """
    if not url.endswith('/translate'):
        if not url.endswith('/'):
            url += "/translate"
        else:
            url += "translate"

    originalText = text

    # get any links from the text
    links = getLinksFromContent(text)

    # LibreTranslate doesn't like markup
    text = removeHtml(text)

    # remove any links from plain text version of the content
    for _, url in links.items():
        text = text.replace(url, '')

    ltParams = {
        "q": text,
        "source": source,
        "target": target
    }

    if apiKey:
        ltParams["api_key"] = apiKey

    urlParams = parse.urlencode(ltParams)

    req = request.Request(url, data=urlParams.encode())
    try:
        response = request.urlopen(req)
    except BaseException:
        print('Unable to translate: ' + text)
        return originalText

    response_str = response.read().decode()

    translatedText = \
        '<p>' + json.loads(response_str)['translatedText'] + '</p>'

    # append links form the original text
    if links:
        translatedText = addLinksToContent(translatedText, links)
    return translatedText


def autoTranslatePost(baseDir: str, postJsonObject: {},
                      systemLanguage: str, translate: {}) -> str:
    """Tries to automatically translate the given post
    """
    if not hasObjectDict(postJsonObject):
        return ''
    msgObject = postJsonObject['object']
    if not msgObject.get('contentMap'):
        return ''
    if not isinstance(msgObject['contentMap'], dict):
        return ''

    # is the language for this post supported by libretranslate?
    libretranslateUrl = getConfigParam(baseDir, "libretranslateUrl")
    if not libretranslateUrl:
        return ''
    libretranslateApiKey = getConfigParam(baseDir, "libretranslateApiKey")
    langList = \
        _libretranslateLanguages(libretranslateUrl, libretranslateApiKey)
    for lang in langList:
        if msgObject['contentMap'].get(lang):
            content = msgObject['contentMap'][lang]
            translatedText = \
                _libretranslate(libretranslateUrl, content,
                                lang, systemLanguage,
                                libretranslateApiKey)
            if translatedText:
                if removeHtml(translatedText) == removeHtml(content):
                    return content
                translatedText = \
                    '<p>' + translate['Translated'].upper() + '</p>' + \
                    translatedText
            return translatedText
    return ''