From 4605baa2897d3297a4b3de37bfeb88315ddcb56f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mat=C4=9Bj=20Such=C3=A1nek?= <matejsuchanek97@gmail.com>
Date: Sun, 11 Mar 2018 15:30:33 +0100
Subject: [PATCH] Let sysops see difflinks to deleted revisions on
 Special:AbuseLog

Bug: T261630
Change-Id: I01eeecea28cbd3520702155860b340ea673bab0d
---
 includes/pagers/AbuseLogPager.php    | 26 ++++++++++-
 includes/special/SpecialAbuseLog.php | 67 +++++++++++++++++++++++++++-
 2 files changed, 90 insertions(+), 3 deletions(-)

diff --git a/includes/pagers/AbuseLogPager.php b/includes/pagers/AbuseLogPager.php
index e5e8fe3df..95ae85432 100644
--- a/includes/pagers/AbuseLogPager.php
+++ b/includes/pagers/AbuseLogPager.php
@@ -17,16 +17,26 @@ class AbuseLogPager extends ReverseChronologicalPager {
 	/** @var LinkBatchFactory */
 	private $linkBatchFactory;
 
+	/** @var bool */
+	private $joinWithArchive;
+
 	/**
 	 * @param SpecialAbuseLog $form
 	 * @param array $conds
 	 * @param LinkBatchFactory $linkBatchFactory
+	 * @param bool $joinWithArchive
 	 */
-	public function __construct( SpecialAbuseLog $form, array $conds, LinkBatchFactory $linkBatchFactory ) {
+	public function __construct(
+		SpecialAbuseLog $form,
+		array $conds,
+		LinkBatchFactory $linkBatchFactory,
+		bool $joinWithArchive = false
+	) {
 		parent::__construct( $form->getContext(), $form->getLinkRenderer() );
 		$this->mForm = $form;
 		$this->mConds = $conds;
 		$this->linkBatchFactory = $linkBatchFactory;
+		$this->joinWithArchive = $joinWithArchive;
 	}
 
 	/**
@@ -67,6 +77,20 @@ class AbuseLogPager extends ReverseChronologicalPager {
 			],
 		];
 
+		if ( $this->joinWithArchive ) {
+			$info['tables'][] = 'archive';
+			$info['fields'][] = 'ar_timestamp';
+			$info['join_conds']['archive'] = [
+				'LEFT JOIN',
+				[
+					'afl_wiki IS NULL',
+					'afl_rev_id IS NOT NULL',
+					'rev_id IS NULL',
+					'ar_rev_id=afl_rev_id',
+				]
+			];
+		}
+
 		if ( !$this->mForm->canSeeHidden( $this->getUser() ) ) {
 			$info['conds']['afl_deleted'] = 0;
 		}
diff --git a/includes/special/SpecialAbuseLog.php b/includes/special/SpecialAbuseLog.php
index 3f7ea75ac..621bbcc81 100644
--- a/includes/special/SpecialAbuseLog.php
+++ b/includes/special/SpecialAbuseLog.php
@@ -1,6 +1,7 @@
 <?php
 
 use MediaWiki\Cache\LinkBatchFactory;
+use MediaWiki\Linker\LinkTarget;
 use MediaWiki\Logger\LoggerFactory;
 use MediaWiki\MediaWikiServices;
 use MediaWiki\Permissions\PermissionManager;
@@ -603,7 +604,12 @@ class SpecialAbuseLog extends AbuseFilterSpecialPage {
 			}
 		}
 
-		$pager = new AbuseLogPager( $this, $conds, $this->linkBatchFactory );
+		$pager = new AbuseLogPager(
+			$this,
+			$conds,
+			$this->linkBatchFactory,
+			$this->canSeeUndeleteDiffs()
+		);
 		$pager->doQuery();
 		$result = $pager->getResult();
 		if ( $result && $result->numRows() !== 0 ) {
@@ -623,7 +629,12 @@ class SpecialAbuseLog extends AbuseFilterSpecialPage {
 		$out = $this->getOutput();
 		$user = $this->getUser();
 
-		$pager = new AbuseLogPager( $this, [], $this->linkBatchFactory );
+		$pager = new AbuseLogPager(
+			$this,
+			[],
+			$this->linkBatchFactory,
+			$this->canSeeUndeleteDiffs()
+		);
 
 		[
 			'tables' => $tables,
@@ -737,6 +748,44 @@ class SpecialAbuseLog extends AbuseFilterSpecialPage {
 		$out->addHTML( Xml::tags( 'fieldset', null, $output ) );
 	}
 
+	/**
+	 * Can this user see diffs generated by Special:Undelete?
+	 * @see \SpecialUndelete
+	 *
+	 * @return bool
+	 */
+	private function canSeeUndeleteDiffs() : bool {
+		if ( !$this->permissionManager->userHasRight( $this->getUser(), 'deletedhistory' ) ) {
+			return false;
+		}
+
+		return $this->permissionManager->userHasAnyRight(
+			$this->getUser(), 'deletedtext', 'undelete' );
+	}
+
+	/**
+	 * Can this user see diffs generated by Special:Undelete for the page?
+	 * @see \SpecialUndelete
+	 * @param LinkTarget $page
+	 *
+	 * @return bool
+	 */
+	private function canSeeUndeleteDiffForPage( LinkTarget $page ) : bool {
+		if ( !$this->canSeeUndeleteDiffs() ) {
+			return false;
+		}
+
+		foreach ( [ 'deletedtext', 'undelete' ] as $action ) {
+			if ( $this->permissionManager->userCan(
+				$action, $this->getUser(), $page, PermissionManager::RIGOR_QUICK
+			) ) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
 	/**
 	 * Helper function to select a row with private details and some more context
 	 * for an AbuseLog entry.
@@ -1088,6 +1137,20 @@ class SpecialAbuseLog extends AbuseFilterSpecialPage {
 					[],
 					[ 'diff' => 'prev', 'oldid' => $row->rev_id ]
 				);
+			} elseif (
+				isset( $row->ar_timestamp ) && $row->ar_timestamp
+				&& $this->canSeeUndeleteDiffForPage( $title )
+			) {
+				$diffLink = $linkRenderer->makeKnownLink(
+					SpecialPage::getTitleFor( 'Undelete' ),
+					new HtmlArmor( $this->msg( 'abusefilter-log-diff' )->parse() ),
+					[],
+					[
+						'diff' => 'prev',
+						'target' => $title->getPrefixedText(),
+						'timestamp' => $row->ar_timestamp,
+					]
+				);
 			}
 		} else {
 			$pageLink = WikiMap::makeForeignLink( $row->afl_wiki, $row->afl_title );