<?php

// (c) Copyright by authors of the Tiki Wiki CMS Groupware Project
//
// All Rights Reserved. See copyright.txt for details and a complete list of authors.
// Licensed under the GNU LESSER GENERAL PUBLIC LICENSE. See license.txt for details.
// $Id$


class Multilingual_MachineTranslation
{
    const DETECT_LANGUAGE = 'auto';

    private $implementation = 'null';

    public static function force($implementation)
    {
        $self = new self();
        $self->implementation = $implementation;

        return $self;
    }

    public function __construct()
    {
        global $prefs;

        switch ($prefs['lang_machine_translate_implementation']) {
            case 'bing':
                if (! empty($prefs['lang_bing_api_client_id'])) {
                    $this->implementation = 'bing';
                }
                break;

            case 'google':
                if (! empty($prefs['lang_google_api_key'])) {
                    $this->implementation = 'google';
                }
                break;
        }
    }

    public function getAvailableLanguages($realTranslations)
    {
        global $langmapping, $prefs;
        $usedLangs = [];
        foreach ($realTranslations as $trad) {
            $usedLangs[] = $trad['lang'];
        }

        if ($prefs['restrict_language'] === 'y' && ! empty($prefs['available_languages'])) {
            $candidates = [];

            //restrict langs available for machine translation to those
            //available on the site
            foreach ($prefs['available_languages'] as $availLang) {
                $candidates[$availLang] = $langmapping[$availLang];
            }
        } else {
            $candidates = $langmapping;
        }

        //restrict langs available for machine translation to those
        //not already used for human translation
        foreach ($usedLangs as $usedLang) {
            unset($candidates[$usedLang]);
        }


        //restrict langs available for machine translation to those
        //available from Google Translate
        $proposed = [];
        $supportedLanguages = $this->getHtmlImplementation('', '')
            ->getSupportedLanguages();
        foreach ($candidates as $langCandidate => $name) {
            if (isset($supportedLanguages[$langCandidate])) {
                $proposed[] = [
                    'lang' => $langCandidate,
                    'langName' => is_array($name) ? reset($name) : $name,
                ];
            }
        }
        return $proposed;
    }

    public function getHtmlImplementation($source, $target)
    {
        global $prefs;

        $handler = null;

        switch ($this->implementation) {
            case 'bing':
                $clientId = $prefs['lang_bing_api_client_id'];
                $clientSecret = $prefs['lang_bing_api_client_secret'];
                $handler = new Multilingual_MachineTranslation_BingTranslateWrapper($clientId, $clientSecret, $source, $target);
                break;
            case 'google':
                $key = $prefs['lang_google_api_key'];
                $handler = new Multilingual_MachineTranslation_GoogleTranslateWrapper($key, $source, $target, true);
                break;
            case 'null':
            default:
                return new Multilingual_MachineTranslation_Null();
        }

        return new Multilingual_MachineTranslation_Cache($handler, $source . $target);
    }

    public function getDetectImplementation($target)
    {
        return $this->getHtmlImplementation(self::DETECT_LANGUAGE, $target);
    }
}