LicenseHandler: Use current date string in file moved to trash

To prevent errors resulting from trying to move the license file to the
trash when a file with the same name already exists there, use a custom
file name with a time stamp.

Instead of naming the trashed file "license.plist", prepend "dome-key-"
to the filename to make it clear to users that the file came from
DomeKey. Append the current date in the format "2018-10-26-19.28.13"
before the file extension.

1 files changed, 13 insertions, 1 deletions

diff --git a/DomeKey/LicenseHandler.m b/DomeKey/LicenseHandler.m
index 576e255..780efef 100644
--- a/DomeKey/LicenseHandler.m
+++ b/DomeKey/LicenseHandler.m
@@ -75,7 +75,8 @@ static NSString * const LICENSE_FILE_NAME = @"license.plist";
 
         BOOL moved = [[NSFileManager defaultManager]
             moveItemAtURL:[self licensePath]
-            toURL:trash_url
+            toURL:[trash_url
+                URLByAppendingPathComponent:[self trashedLicenseFilename]]
             error:&error];
 
         if (!moved) {
@@ -89,6 +90,17 @@ static NSString * const LICENSE_FILE_NAME = @"license.plist";
     // If license does validate, print a success message
 }
 
++ (NSString *)trashedLicenseFilename
+{
+    NSDate *now = [NSDate date];
+    NSDateFormatter *date_formatter = [[NSDateFormatter alloc] init];
+    [date_formatter setDateFormat:@"yyyy-MM-dd-HH.mm.ss"];
+    NSString *date_string = [date_formatter stringFromDate:now];
+    return [NSString
+        stringWithFormat:@"dome-key-license-%@.plist",
+        date_string];
+}
+
 + (NSURL *)licensePath
 {
     return [[XDG domeKeyDataPath]