<?php

namespace Komma;

use Illuminate\Support\Facades\Input;
use Illuminate\Support\Facades\Session;

class LanguageService
{
    /*
     * Array available languages
     * [languageId => languageSlug]
     */
    protected $availableLanguages;

    /*
     * String default language slug
     */
    protected $defaultLanguage;

    /*
     * String current language slug
     */
    protected $currentLanguage;


    public function setLanguage()
    {
        //if root check the accept language for language indication if isset
        if($this->useAcceptLanguage()) $this->setLanguageByAcceptLanguage();
        else $this->setLanguageBySession();
    }

    public function setLanguageBySession()
    {
        $this->availableLanguages = \Config::get('app.availableLanguages');
        $this->defaultLanguage = \Config::get('app.locale');
        $this->currentLanguage = Session::get('lang', $this->defaultLanguage);
        \App::setLocale($this->currentLanguage);
    }

    public function setLanguageByAcceptLanguage()
    {
        //convert accept language to language array ordered on preference
        $langArray = $this->convertAcceptLanguage($_SERVER["HTTP_ACCEPT_LANGUAGE"]);

        //Loop trough the array a preferred language
        foreach (array_keys($langArray) as $lang)
        {
            //check if it is in available languages
            foreach (\Config::get('app.availableLanguages') as $availableLanguage){
                //if there is a match, set language and return
                if (strpos($lang, $availableLanguage) === 0) {
                    $this->currentLanguage = $availableLanguage;
                    Session::set('lang', $availableLanguage);
                    return;
                }
            }
        }
    }

    /*
     * Set Current Language by URI
     */
    public function setCurrentLanguage($lang)
    {
        $this->setLanguage();
        if( ! in_array($lang, $this->availableLanguages)) echo 'error in set Language';

        $this->currentLanguage = $lang;
        Session::set('lang', $lang);
        \App::setLocale($lang);
    }

    /**
     * Check if current route is correct with set language
     */
    public function checkRouteWithSetLanguage()
    {
        $segments = \Request::segments();
        if(sizeof($segments) > 0)
        {
            $lang = \DB::table('languages')
                ->where('iso_2', '=', $segments[0])
                ->first();

            if($lang != null) $this->setCurrentLanguage($lang->iso_2);
        }
    }

    public function getCurrentLanguageId()
    {
        $lang = $this->getLangByIso(\App::getLocale());
        return $lang->id;
    }

    public function getCurrentLanguageIso()
    {
        $lang = $this->getLangByIso(\App::getLocale());
        return $lang->iso_2;
    }

    public function getLangByIso($langIso)
    {
        return \DB::table('languages')
            ->where('iso_2', '=', $langIso)
            ->first();
    }

    public function getIsoById($id)
    {
        return \DB::table('languages')
            ->where('id', '=', $id)
            ->first();
    }

    /**
     * Check if we should use the Accept Language
     * @return bool
     */
    private function useAcceptLanguage()
    {
        // Only use on root
        if( ! sizeof(\Request::segments()) == 0) return false;

        // No Accept Language available
        if( ! isset($_SERVER["HTTP_ACCEPT_LANGUAGE"]) ) return false;

        // No Session found
        if(\Session::has('lang')) return false;

        return true;
    }


    /**
     * Encode accept language header
     * http://www.thefutureoftheweb.com/blog/use-accept-language-header
     *
     * @param $serverString
     * @return array
     */
    private function convertAcceptLanguage($serverString)
    {
        $langs = array();

        // break up string into pieces (languages and q factors)
        preg_match_all('/([a-z]{1,8}(-[a-z]{1,8})?)\s*(;\s*q\s*=\s*(1|0\.[0-9]+))?/i', $serverString, $lang_parse);

        if(count($lang_parse[1]))
        {
            // create a list like "en" => 0.8
            $langs = array_combine($lang_parse[1], $lang_parse[4]);

            // set default to 1 for any without q factor
            foreach ($langs as $lang => $val)
            {
                if($val === '') $langs[$lang] = 1;
            }

            // sort list based on value
            arsort($langs, SORT_NUMERIC);
        }

        return $langs;
    }

}