Fix first reminder too early, offset bugs.

Schedule first reminder date relative to now, handle overflow

// FREEBIE

Signal/src/ViewControllers/DebugUI/DebugUIMisc.m

@@ -116,6 +116,12 @@ NS_ASSUME_NONNULL_BEGIN
                                                         completion:nil];
                                      }]];
 
+    [items addObject:[OWSTableItem itemWithTitle:@"Reset 2FA Repetition Interval"
+                                     actionBlock:^() {
+                                         [OWS2FAManager.sharedManager setDefaultRepetitionInterval];
+                                     }]];
+
+
 #ifdef DEBUG
     [items addObject:[OWSTableItem subPageItemWithText:@"Share UIImage"
                                            actionBlock:^(UIViewController *viewController) {

SignalServiceKit/src/Util/OWS2FAManager.h

@@ -33,6 +33,9 @@ typedef void (^OWS2FAFailure)(NSError *error);
 
 - (void)updateRepetitionIntervalWithWasSuccessful:(BOOL)wasSuccessful;
 
+// used for testing
+- (void)setDefaultRepetitionInterval;
+
 @end
 
 NS_ASSUME_NONNULL_END

SignalServiceKit/src/Util/OWS2FAManager.m

@@ -95,6 +95,9 @@ const NSUInteger kDaySecs = kHourSecs * 24;
 
     [self.dbConnection setObject:pin forKey:kOWS2FAManager_PinCode inCollection:kOWS2FAManager_Collection];
 
+    // Schedule next reminder relative to now
+    self.lastSuccessfulReminderDate = [NSDate new];
+
     [[NSNotificationCenter defaultCenter] postNotificationNameAsync:NSNotificationName_2FAStateDidChange
                                                              object:nil
                                                            userInfo:nil];
@@ -232,14 +235,15 @@ const NSUInteger kDaySecs = kHourSecs * 24;
 
     NSUInteger oldIndex =
         [allIntervals indexOfObjectPassingTest:^BOOL(NSNumber *_Nonnull obj, NSUInteger idx, BOOL *_Nonnull stop) {
-            return oldInterval >= (NSTimeInterval)obj.doubleValue;
+            return oldInterval <= (NSTimeInterval)obj.doubleValue;
         }];
 
     NSUInteger newIndex;
     if (wasSuccessful) {
         newIndex = oldIndex + 1;
     } else {
-        newIndex = oldIndex - 1;
+        // prevent overflow
+        newIndex = oldIndex <= 0 ? 0 : oldIndex - 1;
     }
 
     // clamp to be valid
@@ -249,6 +253,13 @@ const NSUInteger kDaySecs = kHourSecs * 24;
     return newInterval;
 }
 
+- (void)setDefaultRepetitionInterval
+{
+    [self.dbConnection setDouble:self.defaultRepetitionInterval
+                          forKey:kOWS2FAManager_RepetitionInterval
+                    inCollection:kOWS2FAManager_Collection];
+}
+
 @end
 
 NS_ASSUME_NONNULL_END