<?php
/*
**	$Id$
**
**	Copyright (C) 1995-2008 by the ITools Authors.
**	This file is part of ITools - the Internet Tools Library
**
**	ITools is free software; you can redistribute it and/or modify
**	it under the terms of the GNU General Public License as published by
**	the Free Software Foundation; either version 3 of the License, or
**	(at your option) any later version.
**
**	ITools is distributed in the hope that it will be useful,
**	but WITHOUT ANY WARRANTY; without even the implied warranty of
**	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
**	GNU General Public License for more details.
**
**	You should have received a copy of the GNU General Public License
**	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

class it_text
{
	var $actlanguage;			# Selected language
	var $defaultlanguage;			# Browser language
	var $languages = array();		# Active languages
	var $languages_available = array();	# Available languages
	var $statictext = array();		# Text array, read from php file on init

/**
 * Constructor
 * Loads all texts.php in include path for translated labels. Singleton; if instanciated mutiple times, texts are merged
 * Example texts.php: <?php return array('_' => array('en'=>"English", 'de'=>"Deutsch"), 'edit'=>array('en'=>"Edit", 'de'=>("Editieren")));
 * @param $p['fallbacklanguage'] optional language to use for undefined texts (useful for partially translated projects)
 * @param $p['forcelanguage'] optional language to use instead of user's preferred language
 * @param $p['global'] store text object in global it_text for global functions (default: true)
 * @param $p['phpfile'] optional texts file(s), default: all texts.php in include path
 * @param $p['phpfiles'] text files to load in addition to $p['phpfile'] (Note: $p['phpfile'] defaults to all texts.php files in include path)
 */
function it_text($p = array())
{
	if (!$p['phpfile'])
	{
		# Find all texts.php in path (abs path in case we need to save)
		foreach (explode(PATH_SEPARATOR, ini_get('include_path')) as $dir)
			if (file_exists($phpfile = "$dir/texts.php"))
				$p['phpfiles'][] = $phpfile;
	}

	$this->p = ($p += array(
		'global' => true,
		'phpfiles' => array_unique(array_merge((array)$p['phpfiles'], (array)$p['phpfile'])),
	));

	# Read and merge texts from php files if none defined yet
	foreach ($p['phpfiles'] as $phpfile)
	{
		$oldtext = $this->statictext;
		if (is_array($ret = include($phpfile)))
			$this->statictext += $ret;
		else
			$this->statictext = $oldtext + $this->statictext; # FIXME: compatibility mode
	}

	# Get array of supported languages and their names
	$this->languages_available = (array)$this->statictext['_'];
	foreach ($this->languages_available as $code => $languagename)
	{
		# Only use a language in browser detection below if it's not disabled by a leading '-'
		if (substr($languagename, 0, 1) != '-')
		{
			$this->languages[$code] = $languagename;
			if (!$this->actlanguage)
				$this->initlang($code, "setting failsafe language");
		}
	}

	# Set our default language according to browser preference
	if (isset($_SERVER['HTTP_ACCEPT_LANGUAGE']))
	{
		foreach (explode(',', $_SERVER['HTTP_ACCEPT_LANGUAGE']) as $code)
			if ($this->initlang($code, "setting language from browser") || $this->initlang(substr($code, 0, 2), "setting language family from browser"))
				break;
	}
	$this->defaultlanguage = $this->actlanguage;

	$this->initlang(it::match('\.([a-z]{2})\.[^./]+$', $_SERVER['PHP_SELF']), "setting language from url override");
	$this->initlang($p['forcelanguage'], "setting language from programmer override");

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


# internal: overwrite language setting if code is valid, return success
function initlang($code)
{
	if ($this->languages[$code])
		$this->actlanguage = $code;

	return $this->languages[$code];
}


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


/**
 * INTERNAL function for T(): : Return translated text in the selected language
 */
function text($label, $language = null)
{	
	if (!$language)
		$language = $this->actlanguage;

	$text = $this->statictext[$label][$language];
	if (!isset($text))
	{
		$text = $this->statictext[$label][$this->p['fallbacklanguage']];
		if (!isset($text))
		{
			$text = "<span style='background:#F88' title='$label (" . it_debug::backtrace(array('levels'=>1, 'skipfiles'=>"text|auto_prepend")) . ")'>$label</span'>";
			it::error(array('title'=>"unknown label $label language $language - see /tmp/alertdata/alert.log", 'backtraceskip'=>2, 'blockmail'=>21600));
		}
	}

	if ($GLOBALS['debug_texts'] && !eregi('submit|reset|button|_search$|service|claim', $label))
		$text = "<span style='background:#8F8' title='$label (" . it_debug::backtrace(array('levels'=>1, 'skipfiles'=>"text|auto_prepend")) . ")'>" . ($text ? $text : $label) . "</span>";

	return $text;
}


/**
 * INTERNAL function for ET(): Return translated text with values replaced
 */
function etext($label, $values = null, $language = null)
{
	return $this->transmogrify($this->text($label, $language), $values);
}


/**
 * INTERNAL function for T_set_language()
 */
function set_language($language)
{
	$this->actlanguage = $this->languages_available[$language] ? $language : $this->defaultlanguage;
}


/**
 * INTERNAL function for T_lang(): Get active language
 */
function get_language()
{
	return $this->actlanguage;
}


/**
 * INTERNAL function for T_exists(): Check if a text entry for a specific label exists
 */
function text_exists($label, $language = null)
{
	return isset($this->statictext[$label][isset($language) ? $language : $this->actlanguage]) || $this->p['fallbacklanguage'] && isset($this->statictext[$label][$this->p['fallbacklanguage']]);
}


/**
 * 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;
}


/**
 * 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
	uksort($this->statictext, "strnatcmp");
	$this->statictext = array_merge(array('_' => $this->statictext['_']), $this->statictext);

	$oldmask = umask(002);
	if ((count($this->p['phpfiles']) == 1) && ($f = fopen($this->p['phpfiles'][0], 'w')))
	{
		$result = (fputs($f, '<?php return ' . strtr(var_export($this->statictext, true), array("=> \n  array (" => "=> array(", "array (\n  '_'" => "array(\n'_'", "\n  ),\n  " => "\n),\n", "\n  ),\n" => "\n),\n", "\r" => "")) . ";\n?>\n") !== false);
		fclose($f);
	}

	umask($oldmask);
	return $result;
}

} /* End class it_text */
?>