<?php
/**
 * Take page text out of an XML dump file and render basic HTML out to files.
 * This is *NOT* suitable for publishing or offline use; it's intended for
 * running comparative tests of parsing behavior using real-world data.
 *
 * Templates etc are pulled from the local wiki database, not from the dump.
 *
 * Copyright (C) 2011 Platonides - http://www.mediawiki.org/
 * 
 * This program 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 * @ingroup Maintenance
 */
 
require_once( dirname( __FILE__ ) . '/dumpIterator.php' );

class CompareParsers extends DumpIterator {

	private $count = 0;

	public function __construct() {
		parent::__construct();
		$this->saveFailed = false;
		$this->mDescription = "Run a file or dump with several parsers";
		$this->addOption( 'parser1', 'The first parser to compare.', true, true );
		$this->addOption( 'parser2', 'The second parser to compare.', true, true );
		$this->addOption( 'tidy', 'Run tidy on the articles.', false, false );
		$this->addOption( 'save-failed', 'Folder in which articles which differ will be stored.', false, true );
		$this->addOption( 'show-diff', 'Show a diff of the two renderings.', false, false );
		$this->addOption( 'diff-bin', 'Binary to use for diffing (can also be provided by DIFF env var).', false, false );
		$this->addOption( 'strip-parameters', 'Remove parameters of html tags to increase readability.', false, false );
		$this->addOption( 'show-parsed-output', 'Show the parsed html if both Parsers give the same output.', false, false );
	}

	public function checkOptions() {
		if ( $this->hasOption('save-failed') ) {
			$this->saveFailed = $this->getOption('save-failed');
		}
		
		$this->stripParametersEnabled = $this->hasOption( 'strip-parameters' );
		$this->showParsedOutput = $this->hasOption( 'show-parsed-output' );
		
		$this->showDiff = $this->hasOption( 'show-diff' );
		if ( $this->showDiff ) {
			$bin = $this->getOption( 'diff-bin', getenv( 'DIFF' ) );
			if ( $bin != '' ) {
				global $wgDiff;
				$wgDiff = $bin;
			}
		}
		
		$user = new User();		
		$this->options = ParserOptions::newFromUser( $user );
		
		if ( $this->hasOption( 'tidy' ) ) {
			global $wgUseTidy;
			if ( !$wgUseTidy ) {
				$this->error( 'Tidy was requested but $wgUseTidy is not set in LocalSettings.php', true );
			}
			$this->options->setTidy( true );
		}
		
		$this->failed = 0;
	}
	
	public function conclusions() {	
		$this->error( "{$this->failed} failed revisions out of {$this->count}" );
		if ($this->count > 0)
			$this->output( " (" . ( $this->failed / $this->count ) . "%)\n" );
	}
	
	function stripParameters( $text ) {
		if ( !$this->stripParametersEnabled ) {
			return $text;
		}
		return preg_replace( '/(<a) [^>]+>/', '$1>', $text );
	}
	
	/**
	 * Callback function for each revision, parse with both parsers and compare
	 * @param $rev Revision
	 */
	public function processRevision( $rev ) {
		$title = $rev->getTitle();
				
		$parser1Name = $this->getOption( 'parser1' );
		$parser2Name = $this->getOption( 'parser2' );
		
		self::checkParserLocally( $parser1Name );
		self::checkParserLocally( $parser2Name );
		
		$parser1 = new $parser1Name();
		$parser2 = new $parser2Name();
		
		$output1 = $parser1->parse( $rev->getText(), $title, $this->options );
		$output2 = $parser2->parse( $rev->getText(), $title, $this->options );

		if ( $output1->getText() != $output2->getText() ) {
			$this->failed++;
			$this->error( "Parsing for {$title->getPrefixedText()} differs\n" );
			
			if ( $this->saveFailed ) {
				file_put_contents( $this->saveFailed . '/' . rawurlencode( $title->getPrefixedText() ) . ".txt", $rev->getText());
			}
			if ( $this->showDiff ) {
				$this->output( wfDiff( $this->stripParameters( $output1->getText() ), $this->stripParameters( $output2->getText() ), '' ) );
			}
		} else {
			$this->output( $title->getPrefixedText() . "\tOK\n" );
			if ( $this->showParsedOutput ) {
				$this->output( $this->stripParameters( $output1->getText() ) );
			}
		}
	}
	
	private static function checkParserLocally( $parserName ) {
		/* Look for the parser in a file appropiately named in the current folder */
		if ( !class_exists( $parserName ) && file_exists( "$parserName.php" ) ) {
			global $wgAutoloadClasses;
			$wgAutoloadClasses[ $parserName ] = realpath( '.' ) . "/$parserName.php";
		}
	}

}

$maintClass = "CompareParsers";
require_once( RUN_MAINTENANCE_IF_MAIN );
