/**
 * Class for a set of entries for translation and their associated headers
 *
 * @version $Id: translations.php 1157 2015-11-20 04:30:11Z dd32 $
 * @package pomo
 * @subpackage translations
 */

require_once dirname(__FILE__) . '/entry.php';

if ( ! class_exists( 'Translations', false ) ):
class Translations {
	var $entries = array();
	var $headers = array();

	/**
	 * Add entry to the PO structure
	 *
	 * @param array|Translation_Entry &$entry
	 * @return bool true on success, false if the entry doesn't have a key
	 */
	function add_entry($entry) {
		if (is_array($entry)) {
			$entry = new Translation_Entry($entry);
		}
		$key = $entry->key();
		if (false === $key) return false;
		$this->entries[$key] = &$entry;
		return true;
	}

	/**
	 * @param array|Translation_Entry $entry
	 * @return bool
	 */
	function add_entry_or_merge($entry) {
		if (is_array($entry)) {
			$entry = new Translation_Entry($entry);
		}
		$key = $entry->key();
		if (false === $key) return false;
		if (isset($this->entries[$key]))
			$this->entries[$key]->merge_with($entry);
		else
			$this->entries[$key] = &$entry;
		return true;
	}

	/**
	 * Sets $header PO header to $value
	 *
	 * If the header already exists, it will be overwritten
	 *
	 * TODO: this should be out of this class, it is gettext specific
	 *
	 * @param string $header header name, without trailing :
	 * @param string $value header value, without trailing \n
	 */
	function set_header($header, $value) {
		$this->headers[$header] = $value;
	}

	/**
	 * @param array $headers
	 */
	function set_headers($headers) {
		foreach($headers as $header => $value) {
			$this->set_header($header, $value);
		}
	}

	/**
	 * @param string $header
	 */
	function get_header($header) {
		return isset($this->headers[$header])? $this->headers[$header] : false;
	}

	/**
	 * @param Translation_Entry $entry
	 */
	function translate_entry(&$entry) {
		$key = $entry->key();
		return isset($this->entries[$key])? $this->entries[$key] : false;
	}

	/**
	 * @param string $singular
	 * @param string $context
	 * @return string
	 */
	function translate($singular, $context=null) {
		$entry = new Translation_Entry(array('singular' => $singular, 'context' => $context));
		$translated = $this->translate_entry($entry);
		return ($translated && !empty($translated->translations))? $translated->translations[0] : $singular;
	}

	/**
	 * Given the number of items, returns the 0-based index of the plural form to use
	 *
	 * Here, in the base Translations class, the common logic for English is implemented:
	 * 	0 if there is one element, 1 otherwise
	 *
	 * This function should be overridden by the sub-classes. For example MO/PO can derive the logic
	 * from their headers.
	 *
	 * @param integer $count number of items
	 */
	function select_plural_form($count) {
		return 1 == $count? 0 : 1;
	}

	/**
	 * @return int
	 */
	function get_plural_forms_count() {
		return 2;
	}

	/**
	 * @param string $singular
	 * @param string $plural
	 * @param int    $count
	 * @param string $context
	 */
	function translate_plural($singular, $plural, $count, $context = null) {
		$entry = new Translation_Entry(array('singular' => $singular, 'plural' => $plural, 'context' => $context));
		$translated = $this->translate_entry($entry);
		$index = $this->select_plural_form($count);
		$total_plural_forms = $this->get_plural_forms_count();
		if ($translated && 0 <= $index && $index < $total_plural_forms &&
				is_array($translated->translations) &&
				isset($translated->translations[$index]))
			return $translated->translations[$index];
		else
			return 1 == $count? $singular : $plural;
	}

	/**
	 * Merge $other in the current object.
	 *
	 * @param Object &$other Another Translation object, whose translations will be merged in this one
	 * @return void
	 **/
	function merge_with(&$other) {
		foreach( $other->entries as $entry ) {
			$this->entries[$entry->key()] = $entry;
		}
	}

	/**
	 * @param object $other
	 */
	function merge_originals_with(&$other) {
		foreach( $other->entries as $entry ) {
			if ( !isset( $this->entries[$entry->key()] ) )
				$this->entries[$entry->key()] = $entry;
			else
				$this->entries[$entry->key()]->merge_with($entry);
		}
	}
}

class Gettext_Translations extends Translations {
	/**
	 * The gettext implementation of select_plural_form.
	 *
	 * It lives in this class, because there are more than one descendand, which will use it and
	 * they can't share it effectively.
	 *
	 * @param int $count
	 */
	function gettext_select_plural_form($count) {
		if (!isset($this->_gettext_select_plural_form) || is_null($this->_gettext_select_plural_form)) {
			list( $nplurals, $expression ) = $this->nplurals_and_expression_from_header($this->get_header('Plural-Forms'));
			$this->_nplurals = $nplurals;
			$this->_gettext_select_plural_form = $this->make_plural_form_function($nplurals, $expression);
		}
		return call_user_func($this->_gettext_select_plural_form, $count);
	}

	/**
	 * @param string $header
	 * @return array
	 */
	function nplurals_and_expression_from_header($header) {
		if (preg_match('/^\s*nplurals\s*=\s*(\d+)\s*;\s+plural\s*=\s*(.+)$/', $header, $matches)) {
			$nplurals = (int)$matches[1];
			$expression = trim($this->parenthesize_plural_exression($matches[2]));
			return array($nplurals, $expression);
		} else {
			return array(2, 'n != 1');
		}
	}

	/**
	 * Makes a function, which will return the right translation index, according to the
	 * plural forms header
	 * @param int    $nplurals
	 * @param string $expression
	 */
	function make_plural_form_function($nplurals, $expression) {
		$expression = str_replace('n', '$n', $expression);
		$func_body = "
			\$index = (int)($expression);
			return (\$index < $nplurals)? \$index : $nplurals - 1;";
		return create_function('$n', $func_body);
	}

	/**
	 * Adds parentheses to the inner parts of ternary operators in
	 * plural expressions, because PHP evaluates ternary oerators from left to right
	 *
	 * @param string $expression the expression without parentheses
	 * @return string the expression with parentheses added
	 */
	function parenthesize_plural_exression($expression) {
		$expression .= ';';
		$res = '';
		$depth = 0;
		for ($i = 0; $i < strlen($expression); ++$i) {
			$char = $expression[$i];
			switch ($char) {
				case '?':
					$res .= ' ? (';
					$depth++;
					break;
				case ':':
					$res .= ') : (';
					break;
				case ';':
					$res .= str_repeat(')', $depth) . ';';
					$depth= 0;
					break;
				default:
					$res .= $char;
			}
		}
		return rtrim($res, ';');
	}

	/**
	 * @param string $translation
	 * @return array
	 */
	function make_headers($translation) {
		$headers = array();
		// sometimes \ns are used instead of real new lines
		$translation = str_replace('\n', "\n", $translation);
		$lines = explode("\n", $translation);
		foreach($lines as $line) {
			$parts = explode(':', $line, 2);
			if (!isset($parts[1])) continue;
			$headers[trim($parts[0])] = trim($parts[1]);
		}
		return $headers;
	}

	/**
	 * @param string $header
	 * @param string $value
	 */
	function set_header($header, $value) {
		parent::set_header($header, $value);
		if ('Plural-Forms' == $header) {
			list( $nplurals, $expression ) = $this->nplurals_and_expression_from_header($this->get_header('Plural-Forms'));
			$this->_nplurals = $nplurals;
			$this->_gettext_select_plural_form = $this->make_plural_form_function($nplurals, $expression);
		}
	}
}
endif;

if ( ! class_exists( 'NOOP_Translations', false ) ):
/**
 * Provides the same interface as Translations, but doesn't do anything
 */
class NOOP_Translations {
	var $entries = array();
	var $headers = array();

	function add_entry($entry) {
		return true;
	}

	/**
	 *
	 * @param string $header
	 * @param string $value
	 */
	function set_header($header, $value) {
	}

	/**
	 *
	 * @param array $headers
	 */
	function set_headers($headers) {
	}

	/**
	 * @param string $header
	 * @return false
	 */
	function get_header($header) {
		return false;
	}

	/**
	 * @param Translation_Entry $entry
	 * @return false
	 */
	function translate_entry(&$entry) {
		return false;
	}

	/**
	 * @param string $singular
	 * @param string $context
	 */
	function translate($singular, $context=null) {
		return $singular;
	}

	/**
	 *
	 * @param int $count
	 * @return bool
	 */
	function select_plural_form($count) {
		return 1 == $count? 0 : 1;
	}

	/**
	 * @return int
	 */
	function get_plural_forms_count() {
		return 2;
	}

	/**
	 * @param string $singular
	 * @param string $plural
	 * @param int    $count
	 * @param string $context
	 */
	function translate_plural($singular, $plural, $count, $context = null) {
			return 1 == $count? $singular : $plural;
	}

	/**
	 * @param object $other
	 */
	function merge_with(&$other) {
	}
}
endif;

/**
 * Classes, which help reading streams of data from files.
 * Based on the classes from Danilo Segan <danilo@kvota.net>
 *
 * @version $Id: streams.php 1157 2015-11-20 04:30:11Z dd32 $
 * @package pomo
 * @subpackage streams
 */

if ( ! class_exists( 'POMO_Reader', false ) ):
class POMO_Reader {

	var $endian = 'little';
	var $_post = '';

	/**
	 * PHP5 constructor.
	 */
	function __construct() {
		$this->is_overloaded = ((ini_get("mbstring.func_overload") & 2) != 0) && function_exists('mb_substr');
		$this->_pos = 0;
	}

	/**
	 * PHP4 constructor.
	 */
	public function POMO_Reader() {
		self::__construct();
	}

	/**
	 * Sets the endianness of the file.
	 *
	 * @param $endian string 'big' or 'little'
	 */
	function setEndian($endian) {
		$this->endian = $endian;
	}

	/**
	 * Reads a 32bit Integer from the Stream
	 *
	 * @return mixed The integer, corresponding to the next 32 bits from
	 * 	the stream of false if there are not enough bytes or on error
	 */
	function readint32() {
		$bytes = $this->read(4);
		if (4 != $this->strlen($bytes))
			return false;
		$endian_letter = ('big' == $this->endian)? 'N' : 'V';
		$int = unpack($endian_letter, $bytes);
		return reset( $int );
	}

	/**
	 * Reads an array of 32-bit Integers from the Stream
	 *
	 * @param integer count How many elements should be read
	 * @return mixed Array of integers or false if there isn't
	 * 	enough data or on error
	 */
	function readint32array($count) {
		$bytes = $this->read(4 * $count);
		if (4*$count != $this->strlen($bytes))
			return false;
		$endian_letter = ('big' == $this->endian)? 'N' : 'V';
		return unpack($endian_letter.$count, $bytes);
	}

	/**
	 * @param string $string
	 * @param int    $start
	 * @param int    $length
	 * @return string
	 */
	function substr($string, $start, $length) {
		if ($this->is_overloaded) {
			return mb_substr($string, $start, $length, 'ascii');
		} else {
			return substr($string, $start, $length);
		}
	}

	/**
	 * @param string $string
	 * @return int
	 */
	function strlen($string) {
		if ($this->is_overloaded) {
			return mb_strlen($string, 'ascii');
		} else {
			return strlen($string);
		}
	}

	/**
	 * @param string $string
	 * @param int    $chunk_size
	 * @return array
	 */
	function str_split($string, $chunk_size) {
		if (!function_exists('str_split')) {
			$length = $this->strlen($string);
			$out = array();
			for ($i = 0; $i < $length; $i += $chunk_size)
				$out[] = $this->substr($string, $i, $chunk_size);
			return $out;
		} else {
			return str_split( $string, $chunk_size );
		}
	}

	/**
	 * @return int
	 */
	function pos() {
		return $this->_pos;
	}

	/**
	 * @return true
	 */
	function is_resource() {
		return true;
	}

	/**
	 * @return true
	 */
	function close() {
		return true;
	}
}
endif;

if ( ! class_exists( 'POMO_FileReader', false ) ):
class POMO_FileReader extends POMO_Reader {

	/**
	 * @param string $filename
	 */
	function __construct( $filename ) {
		parent::POMO_Reader();
		$this->_f = fopen($filename, 'rb');
	}

	/**
	 * PHP4 constructor.
	 */
	public function POMO_FileReader( $filename ) {
		self::__construct( $filename );
	}

	/**
	 * @param int $bytes
	 */
	function read($bytes) {
		return fread($this->_f, $bytes);
	}

	/**
	 * @param int $pos
	 * @return boolean
	 */
	function seekto($pos) {
		if ( -1 == fseek($this->_f, $pos, SEEK_SET)) {
			return false;
		}
		$this->_pos = $pos;
		return true;
	}

	/**
	 * @return bool
	 */
	function is_resource() {
		return is_resource($this->_f);
	}

	/**
	 * @return bool
	 */
	function feof() {
		return feof($this->_f);
	}

	/**
	 * @return bool
	 */
	function close() {
		return fclose($this->_f);
	}

	/**
	 * @return string
	 */
	function read_all() {
		$all = '';
		while ( !$this->feof() )
			$all .= $this->read(4096);
		return $all;
	}
}
endif;

if ( ! class_exists( 'POMO_StringReader', false ) ):
/**
 * Provides file-like methods for manipulating a string instead
 * of a physical file.
 */
class POMO_StringReader extends POMO_Reader {

	var $_str = '';

	/**
	 * PHP5 constructor.
	 */
	function __construct( $str = '' ) {
		parent::POMO_Reader();
		$this->_str = $str;
		$this->_pos = 0;
	}

	/**
	 * PHP4 constructor.
	 */
	public function POMO_StringReader( $str = '' ) {
		self::__construct( $str );
	}

	/**
	 * @param string $bytes
	 * @return string
	 */
	function read($bytes) {
		$data = $this->substr($this->_str, $this->_pos, $bytes);
		$this->_pos += $bytes;
		if ($this->strlen($this->_str) < $this->_pos) $this->_pos = $this->strlen($this->_str);
		return $data;
	}

	/**
	 * @param int $pos
	 * @return int
	 */
	function seekto($pos) {
		$this->_pos = $pos;
		if ($this->strlen($this->_str) < $this->_pos) $this->_pos = $this->strlen($this->_str);
		return $this->_pos;
	}

	/**
	 * @return int
	 */
	function length() {
		return $this->strlen($this->_str);
	}

	/**
	 * @return string
	 */
	function read_all() {
		return $this->substr($this->_str, $this->_pos, $this->strlen($this->_str));
	}

}
endif;

if ( ! class_exists( 'POMO_CachedFileReader', false ) ):
/**
 * Reads the contents of the file in the beginning.
 */
class POMO_CachedFileReader extends POMO_StringReader {
	/**
	 * PHP5 constructor.
	 */
	function __construct( $filename ) {
		parent::POMO_StringReader();
		$this->_str = file_get_contents($filename);
		if (false === $this->_str)
			return false;
		$this->_pos = 0;
	}

	/**
	 * PHP4 constructor.
	 */
	public function POMO_CachedFileReader( $filename ) {
		self::__construct( $filename );
	}
}
endif;

if ( ! class_exists( 'POMO_CachedIntFileReader', false ) ):
/**
 * Reads the contents of the file in the beginning.
 */
class POMO_CachedIntFileReader extends POMO_CachedFileReader {
	/**
	 * PHP5 constructor.
	 */
	public function __construct( $filename ) {
		parent::POMO_CachedFileReader($filename);
	}

	/**
	 * PHP4 constructor.
	 */
	function POMO_CachedIntFileReader( $filename ) {
		self::__construct( $filename );
	}
}
endif;