From 5f7d7a9ddb5b64dbe7dc0290801c710b5a64bec2 Mon Sep 17 00:00:00 2001
From: Thomas Tanghus <thomas@tanghus.net>
Date: Thu, 28 Nov 2013 14:15:17 +0100
Subject: [PATCH] Prevent duplicate URI. Fix #263

---
 lib/backend/database.php | 34 ++++++++++++++++++++++++++++++----
 lib/utils/properties.php |  2 +-
 2 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/lib/backend/database.php b/lib/backend/database.php
index 7ad7f892..ac894daa 100644
--- a/lib/backend/database.php
+++ b/lib/backend/database.php
@@ -22,9 +22,10 @@
 
 namespace OCA\Contacts\Backend;
 
-use OCA\Contacts\Contact;
-use OCA\Contacts\VObject\VCard;
-use Sabre\VObject\Reader;
+use OCA\Contacts\Contact,
+	OCA\Contacts\VObject\VCard,
+	OCA\Contacts\Utils\Properties,
+	Sabre\VObject\Reader;
 
 /**
  * Subclass this class for Cantacts backends
@@ -516,7 +517,7 @@ class Database extends AbstractBackend {
 			return false;
 		}
 
-		$uri = is_null($uri) ? $contact->UID . '.vcf' : $uri;
+		$uri = is_null($uri) ? $this->uniqueURI($addressbookid, $contact->UID . '.vcf') : $uri;
 		$now = new \DateTime;
 		$contact->REV = $now->format(\DateTime::W3C);
 
@@ -782,4 +783,29 @@ class Database extends AbstractBackend {
 		return $newname;
 	}
 
+	/**
+	* @brief Checks if a contact with the same URI already exist in the address book.
+	* @param string $addressBookId Address book ID.
+	* @param string $uri
+	* @returns string Unique URI
+	*/
+	protected function uniqueURI($addressBookId, $uri) {
+		$stmt = \OCP\DB::prepare( 'SELECT * FROM `' . $this->cardsTableName . '` WHERE `addressbookid` = ? AND `uri` = ?' );
+
+		$result = $stmt->execute(array($addressBookId, $uri));
+
+		if($result->numRows() > 0) {
+			while(true) {
+				$uri = Properties::generateUID() . '.vcf';
+				$result = $stmt->execute(array($addressBookId, $uri));
+				if($result->numRows() > 0) {
+					continue;
+				} else {
+					return $uri;
+				}
+			}
+		} else {
+			return $uri;
+		}
+	}
 }
diff --git a/lib/utils/properties.php b/lib/utils/properties.php
index 09402ab9..cdf42d50 100644
--- a/lib/utils/properties.php
+++ b/lib/utils/properties.php
@@ -197,7 +197,7 @@ Class Properties {
 	}
 
 	public static function generateUID($app = 'contacts') {
-		return date('Ymd\\THis') . '.' . time(). '@' . \OCP\Util::getServerHostName();
+		return date('Ymd\\THis') . '.' . substr(md5(rand().time()), 0, 10). '@' . \OCP\Util::getServerHostName();
 	}
 
 	/**