<?php

/**

 * Class for working with PO files

 *

 * @version $Id: po.php 123 2009-05-13 19:35:43Z nbachiyski $

 * @package pomo

 * @subpackage po

 */

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

define('PO_MAX_LINE_LEN', 79);

ini_set('auto_detect_line_endings', 1);

/**

 * Routines for working with PO files

 */

class PO extends Gettext_Translations {

	/**

	 * Exports headers to a PO entry

	 *

	 * @return string msgid/msgstr PO entry for this PO file headers, doesn't contain newline at the end

	 */

	function export_headers() {

		$header_string = '';

		foreach($this->headers as $header => $value) {

			$header_string.= "$header: $value\n";

		}

		$poified = PO::poify($header_string);

		return rtrim("msgid \"\"\nmsgstr $poified");

	}

	/**

	 * Exports all entries to PO format

	 *

	 * @return string sequence of mgsgid/msgstr PO strings, doesn't containt newline at the end

	 */

	function export_entries() {

		//TODO sorting

		return implode("\n\n", array_map(array('PO', 'export_entry'), $this->entries));

	}

	/**

	 * Exports the whole PO file as a string

	 *

	 * @param bool $include_headers whether to include the headers in the export

	 * @return string ready for inclusion in PO file string for headers and all the enrtries

	 */

	function export($include_headers = true) {

		$res = '';

		if ($include_headers) {

			$res .= $this->export_headers();

			$res .= "\n\n";

		}

		$res .= $this->export_entries();

		return $res;

	}

	/**

	 * Same as {@link export}, but writes the result to a file

	 *

	 * @param string $filename where to write the PO string

	 * @param bool $include_headers whether to include tje headers in the export

	 * @return bool true on success, false on error

	 */

	function export_to_file($filename, $include_headers = true) {

		$fh = fopen($filename, 'w');

		if (false === $fh) return false;

		$export = $this->export($include_headers);

		$res = fwrite($fh, $export);

		if (false === $res) return false;

		return fclose($fh);

	}

	/**

	 * Formats a string in PO-style

	 *

	 * @static

	 * @param string $string the string to format

	 * @return string the poified string

	 */

	function poify($string) {

		$quote = '"';

		$slash = '\\';

		$newline = "\n";

		$replaces = array(

			"$slash" 	=> "$slash$slash",

			"$quote"	=> "$slash$quote",

			"\t" 		=> '\t',

		);

		$string = str_replace(array_keys($replaces), array_values($replaces), $string);

		$po = $quote.implode("${slash}n$quote$newline$quote", explode($newline, $string)).$quote;

		// add empty string on first line for readbility

		if (false !== strpos($string, $newline) &&

				(substr_count($string, $newline) > 1 || !($newline === substr($string, -strlen($newline))))) {

			$po = "$quote$quote$newline$po";

		}

		// remove empty strings

		$po = str_replace("$newline$quote$quote", '', $po);

		return $po;

	}

	/**

	 * Gives back the original string from a PO-formatted string

	 * 

	 * @static

	 * @param string $string PO-formatted string

	 * @return string enascaped string

	 */

	function unpoify($string) {

		$escapes = array('t' => "\t", 'n' => "\n", '\\' => '\\');

		$lines = array_map('trim', explode("\n", $string));

		$lines = array_map(array('PO', 'trim_quotes'), $lines);

		$unpoified = '';

		$previous_is_backslash = false;

		foreach($lines as $line) {

			preg_match_all('/./u', $line, $chars);

			$chars = $chars[0];

			foreach($chars as $char) {

				if (!$previous_is_backslash) {

					if ('\\' == $char)

						$previous_is_backslash = true;

					else

						$unpoified .= $char;

				} else {

					$previous_is_backslash = false;

					$unpoified .= isset($escapes[$char])? $escapes[$char] : $char;

				}

			}

		}

		return $unpoified;

	}

	/**

	 * Inserts $with in the beginning of every new line of $string and 

	 * returns the modified string

	 *

	 * @static

	 * @param string $string prepend lines in this string

	 * @param string $with prepend lines with this string

	 */

	function prepend_each_line($string, $with) {

		$php_with = var_export($with, true);

		$lines = explode("\n", $string);

		// do not prepend the string on the last empty line, artefact by explode

		if ("\n" == substr($string, -1)) unset($lines[count($lines) - 1]);

		$res = implode("\n", array_map(create_function('$x', "return $php_with.\$x;"), $lines));

		// give back the empty line, we ignored above

		if ("\n" == substr($string, -1)) $res .= "\n";

		return $res;

	}

	/**

	 * Prepare a text as a comment -- wraps the lines and prepends #

	 * and a special character to each line

	 *

	 * @access private

	 * @param string $text the comment text

	 * @param string $char character to denote a special PO comment,

	 * 	like :, default is a space

	 */

	function comment_block($text, $char=' ') {

		$text = wordwrap($text, PO_MAX_LINE_LEN - 3);

		return PO::prepend_each_line($text, "#$char ");

	}

	/**

	 * Builds a string from the entry for inclusion in PO file

	 *

	 * @static

	 * @param object &$entry the entry to convert to po string

	 * @return string|bool PO-style formatted string for the entry or

	 * 	false if the entry is empty

	 */

	function export_entry(&$entry) {

		if (is_null($entry->singular)) return false;

		$po = array();

		if (!empty($entry->translator_comments)) $po[] = PO::comment_block($entry->translator_comments);

		if (!empty($entry->extracted_comments)) $po[] = PO::comment_block($entry->extracted_comments, '.');

		if (!empty($entry->references)) $po[] = PO::comment_block(implode(' ', $entry->references), ':');

		if (!empty($entry->flags)) $po[] = PO::comment_block(implode(", ", $entry->flags), ',');

		if (!is_null($entry->context)) $po[] = 'msgctxt '.PO::poify($entry->context);

		$po[] = 'msgid '.PO::poify($entry->singular);

		if (!$entry->is_plural) {

			$translation = empty($entry->translations)? '' : $entry->translations[0];

			$po[] = 'msgstr '.PO::poify($translation);

		} else {

			$po[] = 'msgid_plural '.PO::poify($entry->plural);

			$translations = empty($entry->translations)? array('', '') : $entry->translations;

			foreach($translations as $i => $translation) {

				$po[] = "msgstr[$i] ".PO::poify($translation);

			}

		}

		return implode("\n", $po);

	}

	function import_from_file($filename) {

		$f = fopen($filename, 'r');

		if (!$f) return false;

		$lineno = 0;

		while (true) {

			$res = $this->read_entry($f, $lineno);

			if (!$res) break;

			if ($res['entry']->singular == '') {

				$this->set_headers($this->make_headers($res['entry']->translations[0]));

			} else {

				$this->add_entry($res['entry']);

			}

		}

		PO::read_line($f, 'clear');

		return $res !== false;

	}

	function read_entry($f, $lineno = 0) {

		$entry = new Translation_Entry();

		// where were we in the last step

		// can be: comment, msgctxt, msgid, msgid_plural, msgstr, msgstr_plural

		$context = '';

		$msgstr_index = 0;

		$is_final = create_function('$context', 'return $context == "msgstr" || $context == "msgstr_plural";');

		while (true) {

			$lineno++;

			$line = PO::read_line($f);

			if (!$line)  {

				if (feof($f)) {

					if ($is_final($context))

						break;

					elseif (!$context) // we haven't read a line and eof came

						return null;

					else

						return false;

				} else {

					return false;

				}

			}

			if ($line == "\n") continue;

			$line = trim($line);

			if (preg_match('/^#/', $line, $m)) {

				// the comment is the start of a new entry

				if ($is_final($context)) {

					PO::read_line($f, 'put-back');

					$lineno--;

					break;

				}

				// comments have to be at the beginning

				if ($context && $context != 'comment') {

					return false;

				}

				// add comment

				$this->add_comment_to_entry($entry, $line);;

			} elseif (preg_match('/^msgctxt\s+(".*")/', $line, $m)) {

				if ($is_final($context)) {

					PO::read_line($f, 'put-back');

					$lineno--;

					break;

				}

				if ($context && $context != 'comment') {

					return false;

				}

				$context = 'msgctxt';

				$entry->context .= PO::unpoify($m[1]);

			} elseif (preg_match('/^msgid\s+(".*")/', $line, $m)) {

				if ($is_final($context)) {

					PO::read_line($f, 'put-back');

					$lineno--;

					break;

				}

				if ($context && $context != 'msgctxt' && $context != 'comment') {

					return false;

				}

				$context = 'msgid';

				$entry->singular .= PO::unpoify($m[1]);

			} elseif (preg_match('/^msgid_plural\s+(".*")/', $line, $m)) {

				if ($context != 'msgid') {

					return false;

				}

				$context = 'msgid_plural';

				$entry->is_plural = true;

				$entry->plural .= PO::unpoify($m[1]);

			} elseif (preg_match('/^msgstr\s+(".*")/', $line, $m)) {

				if ($context != 'msgid') {

					return false;

				}

				$context = 'msgstr';

				$entry->translations = array(PO::unpoify($m[1]));

			} elseif (preg_match('/^msgstr\[(\d+)\]\s+(".*")/', $line, $m)) {

				if ($context != 'msgid_plural' && $context != 'msgstr_plural') {

					return false;

				}

				$context = 'msgstr_plural';

				$msgstr_index = $m[1];

				$entry->translations[$m[1]] = PO::unpoify($m[2]);

			} elseif (preg_match('/^".*"$/', $line)) {

				$unpoified = PO::unpoify($line);

				switch ($context) {

					case 'msgid':

						$entry->singular .= $unpoified; break;

					case 'msgctxt':

						$entry->context .= $unpoified; break;

					case 'msgid_plural':

						$entry->plural .= $unpoified; break;

					case 'msgstr':

						$entry->translations[0] .= $unpoified; break;

					case 'msgstr_plural':

						$entry->translations[$msgstr_index] .= $unpoified; break;

					default:

						return false;

				}

			} else {

				return false;

			}

		}

		if (array() == array_filter($entry->translations)) $entry->translations = array();

		return array('entry' => $entry, 'lineno' => $lineno);

	}

	function read_line($f, $action = 'read') {

		static $last_line = '';

		static $use_last_line = false;

		if ('clear' == $action) {

			$last_line = '';

			return true;

		}

		if ('put-back' == $action) {

			$use_last_line = true;

			return true;

		}

		$line = $use_last_line? $last_line : fgets($f);

		$last_line = $line;

		$use_last_line = false;

		return $line;

	}

	function add_comment_to_entry(&$entry, $po_comment_line) {

		$first_two = substr($po_comment_line, 0, 2);

		$comment = trim(substr($po_comment_line, 2));

		if ('#:' == $first_two) {

			$entry->references = array_merge($entry->references, preg_split('/\s+/', $comment));

		} elseif ('#.' == $first_two) {

			$entry->extracted_comments = trim($entry->extracted_comments . "\n" . $comment);

		} elseif ('#,' == $first_two) {

			$entry->flags = array_merge($entry->flags, preg_split('/,\s*/', $comment));

		} else {

			$entry->translator_comments = trim($entry->translator_comments . "\n" . $comment);

		}

	}

	function trim_quotes($s) {

		if ( substr($s, 0, 1) == '"') $s = substr($s, 1);

		if ( substr($s, -1, 1) == '"') $s = substr($s, 0, -1);

		return $s;

	}

}

?>