<?php

/**
 * Translator Class
 * @author franzz
 * @version 1.0
 */
class Translator extends PhpObject
{
	private $sLang;
	private $sDefaultLang;
	private $asLanguages;
	private $asTranslations; // [lang][key_word] = translation

	const LANG_FOLDER = 'languages/';
	const LANG_EXT = '.lang';
	const LANG_SEP = '=';

	/**
	 * Constructor
	 * @param string $sLang leave empty for auto selection based on $_SERVER['HTTP_ACCEPT_LANGUAGE']
	 * @param string $sDefaultLang Fallback language if no fitting language is available
	 */
	public function __construct($sLang='', $sDefaultLang='en')
	{
		parent::__construct(__FILE__, Settings::DEBUG);
		$this->asLanguages = array();
		$this->asTranslations = array();
		$this->loadLanguages();
		$this->setLanguage($sLang, $sDefaultLang);
	}

	public function setLanguage($sLang, $sDefaultLang) {
		$this->sDefaultLang = $sDefaultLang;
		$this->sLang = ($sLang=='')?ToolBox::getUserLanguage($this->asLanguages, $this->sDefaultLang):$sLang;
	}

	public function getTranslation($sTransKey='', $sLang='')
	{
		$oTransText = false;

		//Select language & Scope
		if($sLang=='') $sLang = $this->sLang;
		$bAllTrans = ($sTransKey=='');

		//Look up in the selected language dictionary
		if(in_array($sLang, $this->asLanguages) && ($bAllTrans || array_key_exists($sTransKey, $this->asTranslations[$sLang])))
		{
			$oTransText = $bAllTrans?$this->asTranslations[$sLang]:$this->asTranslations[$sLang][$sTransKey];
		}
		//Look up in the default language dictionary
		elseif(array_key_exists($sTransKey, $this->asTranslations[$this->sDefaultLang]))
		{
			$this->addWarning('Missing translation in "'.$sLang.'" for the key "'.$sTransKey.'", falling back to "'.$this->sDefaultLang.'"');
			$oTransText = $this->asTranslations[$this->sDefaultLang][$sTransKey];
		}
		else $this->addWarning($bAllTrans?'Missing language "'.$sLang.'"':'Missing translation in "'.$sLang.'" for the key "'.$sTransKey.'"');

		return $oTransText;
	}
	
	public function getTranslations($sLang='') {
		return $this->getTranslation('', $sLang);
	}

	public function getHashToPage($asMenuPages)
	{
		$asHashToPage = array();
		foreach($asMenuPages as $sHash)
		{
			foreach($this->asLanguages as $sLang)
			{
				$asHashToPage[$this->getTranslation('menu_'.$sHash.'_key', $sLang)] = $sHash;
			}
		}
		return $asHashToPage;
	}
	
	public function getPageToHash($asMenuPages)
	{
		$asPageToHash = array();
		foreach($asMenuPages as $sHash)
		{
			$asPageToHash[$sHash] = $this->getTranslation('menu_'.$sHash.'_key');
		}
		return $asPageToHash;
	}

	private function loadLanguages()
	{
		//List all available languages
		$asLangPaths = glob(self::getLangPath('*'));
		$this->asLanguages = array_map('basename', $asLangPaths, array_fill(1, count($asLangPaths), self::LANG_EXT));

		//Load languages
		array_walk($this->asLanguages, array($this, 'loadLanguageFile'));
	}

	private function loadLanguageFile($sLang)
	{
		if(!in_array($sLang, $this->asTranslations))
		{
			$sData = file_get_contents(self::getLangPath($sLang));
			$asData = explode("\n", $sData);
			foreach($asData as $sTranslation)
			{
				$iSepPos = mb_stripos($sTranslation, self::LANG_SEP);
				if($iSepPos !== false)
				{
					$sTransKey = trim(mb_substr($sTranslation, 0, $iSepPos));
					$sTransText = trim(mb_substr($sTranslation, $iSepPos+1));
					$this->asTranslations[$sLang][$sTransKey] = $sTransText;
				}
			}
		}
	}

	private static function getLangPath($sLang)
	{
		return self::LANG_FOLDER.$sLang.self::LANG_EXT;
	}
}