<?php

if (!defined( 'MEDIAWIKI' ))
	die();

class AbuseFilterViewDiff extends AbuseFilterView {
	var $mOldVersion = null;
	var $mNewVersion = null;
	var $mFilter = null;
	
	function show( ) {
		$show = $this->loadData();
		
		global $wgOut, $wgUser, $wgLang;
		$this->mSkin = $wgUser->getSkin();
		
		$links = array();
		if ($this->mFilter) {
			$links['abusefilter-history-backedit'] = $this->getTitle( $this->mFilter );
			$links['abusefilter-diff-backhistory'] = $this->getTitle( "history/".$this->mFilter );
		}

		foreach( $links as $msg => $title ) {
			$links[$msg] = $this->mSkin->link( $title, wfMsgExt( $msg, 'parseinline' ) );
		}
		
		$backlinks = $wgLang->pipeList( $links );
		$wgOut->addHTML( Xml::tags( 'p', null, $backlinks ) );
		
		if ($show)
			$wgOut->addHTML( $this->formatDiff() );
	}
	
	function loadData() {
		$oldSpec = $this->mParams[3];
		$newSpec = $this->mParams[4];
		$this->mFilter = $this->mParams[1];
		
		$this->mOldVersion = $this->loadSpec( $oldSpec, $newSpec );
		$this->mNewVersion = $this->loadSpec( $newSpec, $oldSpec );
		
		if (is_null( $this->mOldVersion) || is_null( $this->mNewVersion ) ) {
			global $wgOut;
			$wgOut->addWikiMsg( 'abusefilter-diff-invalid' );
			return false;
		}
		
		return true;
	}
	
	function loadSpec( $spec, $otherSpec ) {
		static $dependentSpecs = array( 'prev', 'next' );
		static $cache = array();
		
		global $wgUser;
		
		if ( AbuseFilter::filterHidden( $this->mFilter ) &&
				!$wgUser->isAllowed( 'abusefilter-modify' ) ) {
			return null;		
		}
		
		if ( isset( $cache[$spec] ) )
			return $cache[$spec];
		
		$dbr = wfGetDB( DB_SLAVE );
		if ( is_numeric($spec) ) {
			$row = $dbr->selectRow(
						'abuse_filter_history',
						'*',
						array( 'afh_id' => $spec, 'afh_filter' => $this->mFilter ),
						__METHOD__
					);
		} elseif ( $spec == 'cur' ) {
			$row = $dbr->selectRow(
						'abuse_filter_history',
						'*',
						array( 'afh_filter' => $this->mFilter ),
						__METHOD__,
						array( 'ORDER BY' => 'afh_timestamp desc' )
					);
		} elseif ($spec == 'prev' && !in_array( $otherSpec, $dependentSpecs ) ) {
			// cached
			$other = $this->loadSpec( $otherSpec, $spec );
			
			$row = $dbr->selectRow(
						'abuse_filter_history',
						'*',
						array(
							'afh_filter' => $this->mFilter,
							'afh_id<'.$dbr->addQuotes( $other['meta']['history_id'] ),
						),
						__METHOD__,
						array( 'ORDER BY' => 'afh_timestamp desc' )
					);
			if ($other && !$row) {
				$t = $this->getTitle(
					"history/".$this->mFilter."/item/".$other['meta']['history_id'] );
				global $wgOut;
				$wgOut->redirect( $t->getFullURL() );
				return;
			}
			
		} elseif ($spec == 'next' && !in_array( $otherSpec, $dependentSpecs ) ) {
			// cached
			$other = $this->loadSpec( $otherSpec, $spec );
			
			$row = $dbr->selectRow(
						'abuse_filter_history',
						'*',
						array(
							'afh_filter' => $this->mFilter,
							'afh_id>'.$dbr->addQuotes( $other['meta']['history_id'] ),
						),
						__METHOD__,
						array( 'ORDER BY' => 'afh_timestamp desc' )
					);
					
			if ($other && !$row) {
				$t = $this->getTitle( 
					"history/".$this->mFilter."/item/".$other['meta']['history_id'] );
				global $wgOut;
				$wgOut->redirect( $t->getFullURL() );
				return;
			}
		}
		
		if (!$row)
			return null;
		
		$data = $this->loadFromHistoryRow( $row );
		$cache[$spec] = $data;
		return $data;
	}
	
	function loadFromHistoryRow( $row ) {
			return array(
				'meta' => array(
						'history_id' => $row->afh_id,
						'modified_by' => $row->afh_user,
						'modified_by_text' => $row->afh_user_text,
						'modified' => $row->afh_timestamp,
					),
				'info' => array(
						'description' => $row->afh_public_comments,
						'flags' => $row->afh_flags,
						'notes' => $row->afh_comments,
					),
				'pattern' => $row->afh_pattern,
				'actions' => unserialize( $row->afh_actions ),
			);
	}
	
	function formatVersionLink( $timestamp, $history_id ) {
		global $wgLang, $wgUser;
		$sk = $wgUser->getSkin();
		
		$filter = $this->mFilter;
		$text = $wgLang->timeanddate( $timestamp );
		$title = $this->getTitle( "history/$filter/item/$history_id" );
		
		$link = $sk->link( $title, $text );
		
		return $link;
	}
	
	function formatDiff() {
		$oldVersion = $this->mOldVersion;
		$newVersion = $this->mNewVersion;
		
		// headings
		$oldLink = $this->formatVersionLink(
												$oldVersion['meta']['modified'],
												$oldVersion['meta']['history_id']
											);
		$newLink = $this->formatVersionLink(
												$newVersion['meta']['modified'],
												$newVersion['meta']['history_id']
											);
											
		$sk = $this->mSkin;
		$oldUserLink = $sk->userLink(
								$oldVersion['meta']['modified_by'],
								$oldVersion['meta']['modified_by_text']
							);
		$newUserLink = $sk->userLink(
								$newVersion['meta']['modified_by'],
								$newVersion['meta']['modified_by_text']
							);
							
		$headings = '';
		$headings .= Xml::tags( 'th', null,
						wfMsgExt( 'abusefilter-diff-item', 'parseinline' ) );
		$headings .= Xml::tags( 'th', null,
							wfMsgExt( 'abusefilter-diff-version',
								array( 'parseinline', 'replaceafter' ),
								array( $oldLink, $oldUserLink,
										$newVersion['meta']['modified_by_text'] )
							)
						);
		$headings .= Xml::tags( 'th', null,
							wfMsgExt( 'abusefilter-diff-version',
								array( 'parseinline', 'replaceafter' ),
								array( $newLink, $newUserLink )
							)
						);
							
		$headings = Xml::tags( 'tr', null, $headings );
		
		// Basic info
		$info = '';
		$info .= $this->getHeaderRow( 'abusefilter-diff-info' );
		$info .= $this->getSimpleRow(
										'abusefilter-edit-description',
										$oldVersion['info']['description'],
										$newVersion['info']['description'],
										'wikitext'
									);
		$info .= $this->getSimpleRow(
										'abusefilter-edit-flags',
										AbuseFilter::formatFlags( $oldVersion['info']['flags'] ),
										AbuseFilter::formatFlags( $newVersion['info']['flags'] )
									);
									
		$info .= $this->getMultiLineRow(
											'abusefilter-edit-notes',
											$oldVersion['info']['notes'],
											$newVersion['info']['notes']
										);
			
		// Pattern
		$info .= $this->getHeaderRow( 'abusefilter-diff-pattern' );
		$info .= $this->getMultiLineRow(
											'abusefilter-edit-rules',
											$oldVersion['pattern'],
											$newVersion['pattern'],
											'text'
										);
		
		// Actions
		$oldActions = $this->stringifyActions( $oldVersion['actions'] );
		$newActions = $this->stringifyActions( $newVersion['actions'] );
		
		$info .= $this->getHeaderRow( 'abusefilter-edit-consequences' );
		$info .= $this->getMultiLineRow(
											'abusefilter-edit-consequences',
											$oldActions,
											$newActions
										);
		
		$html = "<table class='mw-abusefilter-diff'>
		<thead>$headings</thead>
		<tbody>$info</tbody>
</table>";

		$html = Xml::tags( 'h2', null, wfMsgExt( 'abusefilter-diff-title', 'parseinline' ) ) . $html;

		return $html;
	}
	
	function stringifyActions( $actions ) {
		$lines = array();
		
		ksort( $actions );
		foreach( $actions as $action => $parameters ) {
			$lines[] = AbuseFilter::formatAction( $action, $parameters );
		}
		
		if ( !count($lines) )
			$lines[] = '';
		
		return $lines;
	}
	
	function getHeaderRow( $msg ) {
		$html = wfMsgExt( $msg, 'parseinline' );
		$html = Xml::tags( 'th', array( 'colspan' => 3 ), $html );
		$html = Xml::tags( 'tr', array( 'class' => 'mw-abusefilter-diff-header' ), $html );
		
		return $html;
	}
	
	function getSimpleRow( $msg, $old, $new, $format='wikitext' ) {
		$row = '';
		
		$row .= Xml::tags( 'th', null, wfMsgExt( $msg, 'parseinline' ) );
		
		$oldClass = $newClass = 'mw-abusefilter-diff-context';
		if ( trim($old) != trim($new) ) {
			$oldClass = 'mw-abusefilter-diff-removed';
			$newClass = 'mw-abusefilter-diff-added';
		}
		
		if ($format == 'wikitext') {
			global $wgOut;
			$old = $wgOut->parseInline( $old );
			$new = $wgOut->parseInline( $new );
		}
		
		if ($format == 'text') {
			$old = htmlspecialchars($old);
			$new = htmlspecialchars($new);
		}
		
		$row .= Xml::tags( 'td', array( 'class' => $oldClass ), $old );
		$row .= Xml::tags( 'td', array( 'class' => $newClass ), $new );
		
		return Xml::tags( 'tr', null, $row )."\n";
	}
	
	function getMultiLineRow( $msg, $old, $new ) {
		if (!is_array($old))
			$old = explode( "\n", $old );
		if (!is_array($new))
			$new = explode( "\n", $new );
			
		if ( $old == $new ) {
			$old = implode( "<br/>\n", $old );
			$new = implode( "<br/>\n", $new );
			return $this->getSimpleRow( $msg, $old, $new );
		}
		
		// Hacky fix for double-escaping.
		$old = array_map( 'html_entity_decode', $old );
		$new = array_map( 'html_entity_decode', $new );
		
		$row = '';
		$row .= Xml::tags( 'th', null, wfMsgExt( $msg, 'parseinline' ) );
		
		$diff = new Diff( $old, $new );
		$formatter = new TableDiffFormatter();
		$formattedDiff = $formatter->format( $diff );
		$formattedDiff =
			"<table class='mw-abusefilter-diff-multiline'><tbody>$formattedDiff</tbody></table>";
		$row .= Xml::tags( 'td', array( 'colspan' => 2 ), $formattedDiff );
		
		return Xml::tags( 'tr', null, $row )."\n";
	}
}