#!/usr/bin/php
<?php
chdir ( dirname ( __FILE__ ) );
require_once 'common.php';
assertCli ();

/**
 * @file
 * Parses *.ent files into an entity lookup table, and then serializes and
 * writes the whole kaboodle to a file.
 * The resulting file is cached so
 * that this script does not need to be run. This script should rarely,
 * if ever, be run, since HTML's entities are fairly immutable.
 */

// here's where the entity files are located, assuming working directory
// is the same as the location of this PHP file. Needs trailing slash.
$entity_dir = '../docs/entities/';

// defines the output file for the serialized content.
$output_file = '../library/HTMLPurifier/EntityLookup/entities.ser';

// courtesy of a PHP manual comment
function unichr($dec) {
	if ($dec < 128) {
		$utf = chr ( $dec );
	} elseif ($dec < 2048) {
		$utf = chr ( 192 + (($dec - ($dec % 64)) / 64) );
		$utf .= chr ( 128 + ($dec % 64) );
	} else {
		$utf = chr ( 224 + (($dec - ($dec % 4096)) / 4096) );
		$utf .= chr ( 128 + ((($dec % 4096) - ($dec % 64)) / 64) );
		$utf .= chr ( 128 + ($dec % 64) );
	}
	return $utf;
}

if (! is_dir ( $entity_dir ))
	exit ( "Fatal Error: Can't find entity directory.\n" );
if (file_exists ( $output_file ))
	exit ( "Fatal Error: output file already exists.\n" );

$dh = @opendir ( $entity_dir );
if (! $dh)
	exit ( "Fatal Error: Cannot read entity directory.\n" );

$entity_files = array ();
while ( ($file = readdir ( $dh )) !== false ) {
	if (@$file [0] === '.')
		continue;
	if (substr ( strrchr ( $file, "." ), 1 ) !== 'ent')
		continue;
	$entity_files [] = $file;
}
closedir ( $dh );

if (! $entity_files)
	exit ( "Fatal Error: No entity files to parse.\n" );

$entity_table = array ();
$regexp = '/<!ENTITY\s+([A-Za-z0-9]+)\s+"&#(?:38;#)?([0-9]+);">/';

foreach ( $entity_files as $file ) {
	$contents = file_get_contents ( $entity_dir . $file );
	$matches = array ();
	preg_match_all ( $regexp, $contents, $matches, PREG_SET_ORDER );
	foreach ( $matches as $match ) {
		$entity_table [$match [1]] = unichr ( $match [2] );
	}
}

$output = serialize ( $entity_table );

$fh = fopen ( $output_file, 'w' );
fwrite ( $fh, $output );
fclose ( $fh );

echo "Completed successfully.";

// vim: et sw=4 sts=4