<?php
/*
**	$Id$
**
**	ITools - the Internet Tools Library
**
**	Copyright (C) 1995-2006 by the ITools Authors.
**	This program is free software; you can redistribute it and/or
**	modify it under the terms of either the GNU General Public License
**	or the GNU Lesser General Public License, as published by the Free
**	Software Foundation. See http://www.gnu.org/licenses/ for details.
**
*/

class it_text
{
	var $defaultlanguage;			# Preferred language (without cookie)
	var $actlanguage;			# Selected language
	var $actlanguagename;			# Name of selected language
	var $languages = array();		# Active languages
	var $languages_available = array();	# Available languages
	var $language_failsafe;			# First available language. Must be complete (used as fallback)
	var $statictext = array();		# Text array, read from php file on init
	var $unknown_labels = array();		# array for spooling unknown labels in debug mode

/**
 * Constructor
 * @param $p['cookiename'] optional cookie name (default: 'LANGUAGE')
 * @param $p['debug'] optional debug mode: display label of unknown texts, set to 'label' to always display labels instead of actual text
 * @param $p['forcelanguage'] optional language to use instead of user's prefered language
 * @param $p['phpfile'] optional texts file, defaults to service's phpinclude/texts.php
 */
function it_text($p = null)
{
	$this->p = (array)$p + array('cookiename' => 'LANGUAGE', 'debug' => false, 'phpfile' => $GLOBALS['ULTRAHOME'] . '/phpinclude/texts.php');

	# Read $this->statictext from php file if it's not defined yet
	if (!$this->statictext)
		include($this->p['phpfile']);

	# Get array of supported languages and their names
	foreach(array_keys($this->statictext['_']) as $code)
	{
		# If a language's name in '_' is unset, ignore it
		if ($languagename = $this->statictext['_'][$code])
		{
			$this->languages_available[$code] = $languagename;

			# Only use a language in browser/cookie detection below if it's not diasbled by a leading '-'
			if (substr($languagename, 0, 1) != '-')
			{
				$this->languages[$code] = $languagename;
				if (!isset($this->language_failsafe))
					$this->language_failsafe = $code;
			}
		}
	}

	# Set our default language according to browser preference
	if (isset($_SERVER['HTTP_ACCEPT_LANGUAGE']))
	{
		foreach(explode(',', $_SERVER['HTTP_ACCEPT_LANGUAGE']) as $lang)
		{
			if (isset($this->languages[$lang]))
			{
				$this->defaultlanguage = $lang;
				debug("Got language from browser: {$this->defaultlanguage}", 6);
				break;
			}
			else
			{
				$short = substr($lang, 0, 2);
				if (isset($this->languages[$short]))
				{
					$this->defaultlanguage = $short;
					debug("Got language family from browser: {$this->defaultlanguage}", 6);
					break;
				}
			}
		}
		if (count($this->languages) == 0)
			debug("No active languages found!", 5);
	}

	# If no language matched, use failsafe language
	if (!$this->languages[$this->defaultlanguage])
		$this->defaultlanguage = $this->language_failsafe;

	# If a cookie is set, use its value as our active language
	if (isset($_COOKIE[$this->p['cookiename']]) && ($this->languages[$cookie = $_COOKIE[$this->p['cookiename']]]))
	{
		$this->actlanguage = $cookie;
		debug("Got language from cookie: {$this->actlanguage}", 6);
	}

	# If the cookie supplied no valid language, we use our calculated default language
	if (!isset($this->actlanguage))
		$this->actlanguage = $this->defaultlanguage;

	# If the user wants something else, comply
	if (isset($this->p['forcelanguge']) && isset($this->languages[$this->p['forcelanguage']]))
		$this->actlanguage = $this->p['forcelanguage'];

	# And finally, record the name of our active language.
	$this->actlanguagename = $this->languages[$this->actlanguage];

	# Make this object available under $GLOBALS['it_text'], or add my texts to $GLOBALS['it_text'] if it exists
	if (!$GLOBALS['it_text'])
		$GLOBALS['it_text'] =& $this;
	else
		$GLOBALS['it_text']->statictext += $this->statictext;

	debug("Used language is {$this->actlanguagename}, default language is {$this->defaultlanguage}.", 6);
}

/**
 * Instanciate singleton if necessary
 */
function init()
{
	if (!$GLOBALS['it_text'])
		new it_text;
}

/**
 * Return a text in the selected language.
 * @param $label Label of text to return
 * @param $raw Optional unused obsolete parameter
 * @param $language Optional language to return text in.
 * @return Localized text string
 */
function text($label, $raw = null, $language = null)
{
	if ($this->p['debug'] === 'label')
		return $label;
	
	if (!isset($language))
		$language = $this->actlanguage;

	if ($this->statictext[$label][$language] !== '')
		return $this->statictext[$label][$language];

	$this->unknown_labels[] = $label;
	return $this->p['debug'] ? "<blink>$label ($language)</blink>" : $this->statictext[$label][$this->language_failsafe];
}


/**
 * Return a text in the selected language, with correctly encoded umlauts.
 * Replaces variables of the form {obj.var} with value, e.g. {user.name}
 * NOTE: Invalid object names or non-existing variables are simply deleted.
 * @param $label Label of text to return
 * @param $values Associative array containing values to fill in
 * @param $language Optional language to return text in.
 * @return Localized text string with variables replaced by their values
 */
function etext($label, $values = null, $language = null)
{
	return $this->transmogrify($this->text($label, null, $language), $values);
}


/**
 * Change language
 * @param $language New language to set
 * @param $setcookie Optional flag if a cookie is to be set (default: true)
 */
function set_language($language, $setcookie = true)
{
	# If $language is unknown, delete the cookie
	if ($this->languages_available[$language])
	{
		if (!$this->languages[$language])
			debug('Selected an existing but currently disabled language!', 6);
		$this->actlanguage = $language;
		if ($setcookie)
			SetCookie($this->p['cookiename'], $this->actlanguage, time() + 31536000, '/');	# 1 year
	}
	else
	{
		$this->actlanguage = $this->defaultlanguage;
		if ($setcookie)
			SetCookie($this->p['cookiename'], '', time() + 31536000, '/');
	}
}


/**
 * Get active language
 * @return currently active language
 */
function get_language()
{
	return $this->actlanguage;
}


/**
 * Get default language
 * @return default language
 */
function get_default_language()
{
	return $this->defaultlanguage;
}


/**
 * Check if a text entry for a specific label exists
 * @param $label Label to check
 * @return true if text exists in actual (or supplied) language, false otherwise.
 */
function text_exists($label, $language = null)
{
	return isset($this->statictext[$label][isset($language) ? $language : $this->actlanguage]);
}


/**
 * Create / overwrite a text in the selected language. Call dump_php() to make the change permanent.
 * @param $label Label of text to change
 * @param $text New text to set
 * @param $language Optional language that is to be manipulated
 */
function set($label, $text = null, $language = null)
{
	if (!isset($language))
		$language = $this->actlanguage;

	$this->statictext[$label][$language] = $text;
}


/**
 * Replaces variables of the form {obj.var} with value, e.g. {user.name}
 * NOTE: Invalid object names or non-existing variables are simply deleted.
 */
function transmogrify($text, $values = null)
{
	while (preg_match('/{([\w.]+)}/', $text, $regs))
	{
		$path = explode('.', $regs[1]);
		if ($values)
			$value =& $values;
		else
			$value =& $GLOBALS;

		# Recurse into nested arrays/object members
		foreach ($path as $key)
		{
			if (is_object($value))
				$value =& $value->$key;
			else
				$value =& $value[$key];
		}

		$text = str_replace($regs[0], $value, $text);
	}

	return $text;
}


/**
 * when running it_text in debug mode, you can use this to die
 * in case there were unknown labels with a list of all unknown labels
 */
function checkout_unknown_labels()
{
	if ($this->unknown_labels)
		it::fatal('No text found for labels: ' . implode(',', $this->unknown_labels));
}
	

/**
 * Replaces special chars with their TeX equivalent
 * @param $text Text to convert from ISO-8859-1 to TeX encoding
 * @param $convertlinebreaks Whether to convert LFs to TeX linebreaks
 * @return TeX encoded text to be inserted into TeX template
 */
function texify($text, $convertlinebreaks = true)
{
	$translation = array
	(
		'À' => '{\`A}',
		'Á' => "{\'A}",
		'Â' => '{\^A}',
		'Ã' => '{\~A}',
		'Ä' => '{\"A}',
		'Ç' => '{\c C}',
		'È' => '{\`E}',
		'É' => "{\'E}",
		'Ê' => '{\^E}',
		'Ë' => '{\"E}',
		'Ì' => '{\`I}',
		'Í' => "{\'I}",
		'Î' => '{\^I}',
		'Ï' => '{\"I}',
		'Ñ' => '{\~N}',
		'Ò' => '{\`O}',
		'Ó' => "{\'O}",
		'Ô' => '{\^O}',
		'Õ' => '{\~O}',
		'Ö' => '{\"O}',
		'Ù' => '{\`U}',
		'Ú' => "{\'U}",
		'Û' => '{\^U}',
		'Ü' => '{\"U}',
		'ß' => '{\ss}',
		'à' => '{\`a}',
		'á' => "{\'a}",
		'â' => '{\^a}',
		'ã' => '{\~a}',
		'ä' => '{\"a}',
		'ç' => '{\c c}',
		'è' => '{\`e}',
		'é' => "{\'e}",
		'ê' => '{\^e}',
		'ë' => '{\"e}',
		'ì' => '{\`i}',
		'í' => "{\'i}",
		'î' => '{\^i}',
		'ï' => '{\"i}',
		'ñ' => '{\~n}',
		'ò' => '{\`o}',
		'ó' => "{\'o}",
		'ô' => '{\^o}',
		'õ' => '{\~o}',
		'ö' => '{\"o}',
		'ù' => '{\`u}',
		'ú' => "{\'u}",
		'û' => '{\^u}',
		'ü' => '{\"u}',
		'ÿ' => '{\"y}',
		'"' => "''",
		'\\' => '/',
		'%' => '\%',
		'$' => '\$',
		'#' => '\#',
		'&' => '\&',
		'_' => '\_',
		'^' => '',
	);

	if ($convertlinebreaks)
		$translation["\n"] = "\\\\\n";

	return strtr($text, $translation);
}

/**
 * Re-create php text file from $this->statictext
 * @return true if successful, false if not (usually if file is not writeable by user www)
 */
function dump_php()
{
	$result = false;

	# Special sorting: natural, but _ is the first entry
	$keys = array_keys($this->statictext);
	natsort($keys);
	foreach($keys as $key)
		$text[$key] = $this->statictext[$key];
	$this->statictext = array_merge(array('_' => $text['_']), $text);

	$oldmask = umask(002);
	if ($f = fopen($this->p['phpfile'], 'w'))
	{
		$result = (fputs($f, '<?php $this->statictext = ' . strtr(var_export($this->statictext, true), array("=> \n  array (" => "=> array(", "array (\n  '_'" => "array(\n'_'", "\n  ),\n  " => "\n),\n", "\n  ),\n" => "\n)\n")) . ";\n?>\n") !== false);
		fclose($f);
	}

	umask($oldmask);
	return $result;
}

} /* End class it_text */
?>