<?php
if ( ! defined( 'MEDIAWIKI' ) )
	die();

class AbuseFilterHooks {

// So far, all of the error message out-params for these hooks accept HTML.
// Hooray!

	public static function onEditFilter($editor, $text, $section, &$error, $summary) {
		// Load vars
		$vars = array();
		
		global $wgUser;
		$vars = array_merge( $vars, AbuseFilter::generateUserVars( $wgUser ) );
		$vars = array_merge( $vars, AbuseFilter::generateTitleVars( $editor->mTitle , 'ARTICLE' ));
		$vars['ACTION'] = 'edit';
		$vars['SUMMARY'] = $summary;
		
		$old_text = $editor->getBaseRevision() ? $editor->getBaseRevision()->getText() : '';
		$new_text = $editor->textbox1;
		
		$vars['EDIT_DELTA'] = strlen($new_text) - strlen($old_text);
		$vars['OLD_SIZE'] = strlen($old_text);
		$diff = wfDiff( $old_text, $new_text );
		$diff = trim( str_replace( '\No newline at end of file', '', $diff ) );
		$vars['EDIT_DIFF'] = $diff;
		$vars['NEW_SIZE'] = strlen($new_text);

		$vars['OLD_WIKITEXT'] = $old_text;
		$vars['NEW_WIKITEXT'] = $new_text;
		
		// Some more specific/useful details about the changes.
		$diff_lines = explode( "\n", $diff );
		$added_lines = array();
		$removed_lines = array();
		foreach( $diff_lines as $line ) {
			if (strpos( $line, '-' )===0) {
				$removed_lines[] = substr($line,1);
			} elseif (strpos( $line, '+' )===0) {
				$added_lines[] = substr($line,1);
			}
		}
		$vars['ADDED_LINES'] = implode( "\n", $added_lines );
		$vars['REMOVED_LINES'] = implode( "\n", $removed_lines );
		
		// Added links...
		$oldLinks = self::getOldLinks( $editor->mTitle );
		$editInfo = $editor->mArticle->prepareTextForEdit( $text );
		$newLinks = array_keys( $editInfo->output->getExternalLinks() );
		$vars['ALL_LINKS'] = implode( "\n", $newLinks );
		$vars['ADDED_LINKS'] = implode( "\n", array_diff( $newLinks, array_intersect( $newLinks, $oldLinks ) ) );
		$vars['REMOVED_LINKS'] = implode( "\n", array_diff( $oldLinks, array_intersect( $newLinks, $oldLinks ) ) );

		// Pull other useful stuff from $editInfo.
		$newHTML = $vars['NEW_HTML'] = $editInfo->output->getText();
		$newText = $vars['NEW_TEXT'] = preg_replace( '/<[^>]+>/', '', $newHTML );

		$filter_result = AbuseFilter::filterAction( $vars, $editor->mTitle );

		if( $filter_result !== true ){
			$error = $filter_result;
		}
		return true;
	}
	
	/**
	 * Load external links from the externallinks table
	 * Stolen from ConfirmEdit
	 */
	static function getOldLinks( $title ) {
		$dbr = wfGetDB( DB_SLAVE );
		$id = $title->getArticleId(); // should be zero queries
		$res = $dbr->select( 'externallinks', array( 'el_to' ), 
			array( 'el_from' => $id ), __METHOD__ );
		$links = array();
		while ( $row = $dbr->fetchObject( $res ) ) {
			$links[] = $row->el_to;
		}
		return $links;
	}
	
	public static function onGetAutoPromoteGroups( $user, &$promote ) {
		global $wgMemc;
		
		$key = AbuseFilter::autoPromoteBlockKey( $user );
		
		if ($wgMemc->get( $key ) ) {
			$promote = array();
		}
		
		return true;
	}
	
	public static function onAbortMove( $oldTitle, $newTitle, $user, &$error, $reason ) {
		$vars = array();
		
		global $wgUser;
		$vars = array_merge( $vars, AbuseFilter::generateUserVars( $wgUser ),
					AbuseFilter::generateTitleVars( $oldTitle, 'MOVED_FROM' ),
					AbuseFilter::generateTitleVars( $newTitle, 'MOVED_TO' ) );
		$vars['SUMMARY'] = $reason;
		$vars['ACTION'] = 'move';
		
		$filter_result = AbuseFilter::filterAction( $vars, $oldTitle );
		
		$error = $filter_result;
		
		return $filter_result == '' || $filter_result === true;
	}
	
	public static function onArticleDelete( &$article, &$user, &$reason, &$error ) {
		$vars = array();
		
		global $wgUser;
		$vars = array_merge( $vars, AbuseFilter::generateUserVars( $wgUser ),
					AbuseFilter::generateTitleVars( $article->mTitle, 'ARTICLE' ) );
		$vars['SUMMARY'] = $reason;
		$vars['ACTION'] = 'delete';
		
		$filter_result = AbuseFilter::filterAction( $vars, $article->mTitle );
		
		$error = $filter_result;
		
		return $filter_result == '' || $filter_result === true;
	}
	
	public static function onAbortNewAccount( $user, &$message ) {
		wfLoadExtensionMessages( 'AbuseFilter' );
		if ($user->getName() == wfMsgForContent( 'abusefilter-blocker' )) {
			$message = wfMsg( 'abusefilter-accountreserved' );
			return false;
		}
		$vars = array();
		
		$vars['ACTION'] = 'createaccount';
		$vars['ACCOUNTNAME'] = $vars['USER_NAME'] = $user->getName();
		
		$filter_result = AbuseFilter::filterAction( $vars, SpecialPage::getTitleFor( 'Userlogin' ) );
		
		$message = $filter_result;
		
		return $filter_result == '' || $filter_result === true;
	}
	
	public static function onSchemaUpdate() {
		global $wgDatabase;
		
		if ( !$wgDatabase->tableExists( 'abuse_filter' ) ) {
			// Full tables
			dbsource( dirname(__FILE__).'/abusefilter.tables.sql', $wgDatabase );
		}
		
		if ( ! $wgDatabase->fieldExists( 'abuse_filter', 'af_deleted' ) ) {
			dbsource( dirname( __FILE__ ) . '/db_patches/patch-af_deleted.sql' );
		}
		
		return true;
	}
	
	public static function onAbortDeleteQueueNominate( $user, $article, $queue, $reason, &$error ) {
		$vars = array();
		
		$vars = array_merge( $vars, AbuseFilter::generateUserVars( $user ), AbuseFilter::generateTitleVars( $article->mTitle, 'ARTICLE' ) );
		$vars['SUMMARY'] = $reason;
		$vars['ACTION'] = 'delnom';
		$vars['QUEUE'] = $queue;
		
		$filter_result = AbuseFilter::filterAction( $vars, $article->mTitle );
		$error = $filter_result;
		
		return $filter_result == '' || $filter_result === true;
	}

	public static function onRecentChangeSave( $recentChange ) {
		$title = Title::makeTitle( $recentChange->mAttribs['rc_namespace'], $recentChange->mAttribs['rc_title'] );
		$action = $recentChange->mAttribs['rc_log_type'] ? $recentChange->mAttribs['rc_log_type'] : 'edit';
		$actionID = implode( '-', array(
				$title->getPrefixedText(), $recentChange->mAttribs['rc_user_text'], $action
			) );

		if ( !empty( AbuseFilter::$tagsToSet[$actionID] ) && count( $tags = AbuseFilter::$tagsToSet[$actionID]) ) {
			ChangeTags::addTags( $tags, $recentChange->mAttribs['rc_id'], $recentChange->mAttribs['rc_this_oldid'], $recentChange->mAttribs['rc_logid'] );
		}

		return true;
	}

	public static function onListDefinedTags( &$emptyTags ) {
		## This is a pretty awful hack.
		$dbr = wfGetDB( DB_SLAVE );

		$res = $dbr->select( 'abuse_filter_action', 'afa_parameters', array( 'afa_consequence' => 'tag' ), __METHOD__ );

		while( $row = $res->fetchObject() ) {
			$emptyTags = array_filter( array_merge( explode( "\n", $row->afa_parameters ), $emptyTags ) );
		}

		return true;
	}
}