From 5928b906e94de4ac71057905a845a15ff7388623 Mon Sep 17 00:00:00 2001
From: Brion Vibber <brion@users.mediawiki.org>
Date: Fri, 30 May 2008 17:50:04 +0000
Subject: [PATCH] Perform a duplicate check on upload and throw a warning which
 can be observed or ignored.

---
 includes/SpecialUpload.php        | 28 ++++++++++++++++++++++++++++
 languages/messages/MessagesEn.php |  1 +
 2 files changed, 29 insertions(+)

diff --git a/includes/SpecialUpload.php b/includes/SpecialUpload.php
index ac52d44559..a5096b3ede 100644
--- a/includes/SpecialUpload.php
+++ b/includes/SpecialUpload.php
@@ -539,6 +539,9 @@ class UploadForm {
 			if ( !$this->mDestWarningAck ) {
 				$warning .= self::getExistsWarning( $this->mLocalFile );
 			}
+			
+			$warning .= $this->getDupeWarning( $this->mTempPath );
+			
 			if( $warning != '' ) {
 				/**
 				 * Stash the file in a temporary location; the user can choose
@@ -739,6 +742,31 @@ class UploadForm {
 
 		return $output->getText();
 	}
+	
+	/**
+	 * Check for duplicate files and throw up a warning before the upload
+	 * completes.
+	 */
+	function getDupeWarning( $tempfile ) {
+		$hash = File::sha1Base36( $tempfile );
+		$dupes = RepoGroup::singleton()->findBySha1( $hash );
+		if( $dupes ) {
+			global $wgOut;
+			$msg = "<gallery>";
+			foreach( $dupes as $file ) {
+				$title = $file->getTitle();
+				$msg .= $title->getPrefixedText() .
+					"|" . $title->getText() . "\n";
+			}
+			$msg .= "</gallery>";
+			return "<li>" .
+				wfMsgExt( "file-exists-duplicate", array( "parse" ), count( $dupes ) ) .
+				$wgOut->parse( $msg ) .
+				"</li>\n";
+		} else {
+			return '';
+		}
+	}
 
 	/**
 	 * Get a list of blacklisted filename prefixes from [[MediaWiki:filename-prefix-blacklist]]
diff --git a/languages/messages/MessagesEn.php b/languages/messages/MessagesEn.php
index d8e220a3a6..1c9004b016 100644
--- a/languages/messages/MessagesEn.php
+++ b/languages/messages/MessagesEn.php
@@ -1631,6 +1631,7 @@ If you have this image in full resolution upload this one, otherwise change the
 please go back and upload this file under a new name. [[Image:$1|thumb|center|$1]]',
 'fileexists-shared-forbidden' => 'A file with this name exists already in the shared file repository;
 please go back and upload this file under a new name. [[Image:$1|thumb|center|$1]]',
+'file-exists-duplicate'       => 'This file seems to be a duplicate of the following {{PLURAL:$1|file|files}}:',
 'successfulupload'            => 'Successful upload',
 'uploadwarning'               => 'Upload warning',
 'savefile'                    => 'Save file',
-- 
2.20.1