/*
 * Copyright 2017 Google
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#import "FIRMessagingRegistrar.h"

#import "FIRMessagingDefines.h"
#import "FIRMessagingLogger.h"
#import "FIRMessagingPubSubRegistrar.h"
#import "FIRMessagingUtilities.h"
#import "NSError+FIRMessaging.h"

@interface FIRMessagingRegistrar ()

@property(nonatomic, readwrite, assign) BOOL stopAllSubscriptions;

@property(nonatomic, readwrite, strong) FIRMessagingCheckinService *checkinService;
@property(nonatomic, readwrite, strong) FIRMessagingPubSubRegistrar *pubsubRegistrar;

@end

@implementation FIRMessagingRegistrar

- (NSString *)deviceAuthID {
  return self.checkinService.deviceAuthID;
}

- (NSString *)secretToken {
  return self.checkinService.secretToken;
}

- (instancetype)init {
  self = [super init];
  if (self) {
    _checkinService = [[FIRMessagingCheckinService alloc] init];
    // TODO(chliangGoogle): Merge pubsubRegistrar with Registrar as it is hard to track how many
    // checkinService instances by separating classes too often.
    _pubsubRegistrar = [[FIRMessagingPubSubRegistrar alloc] initWithCheckinService:_checkinService];
  }
  return self;
}

#pragma mark - Checkin

- (BOOL)tryToLoadValidCheckinInfo {
  [self.checkinService tryToLoadPrefetchedCheckinPreferences];
  return [self.checkinService hasValidCheckinInfo];
}

#pragma mark - Subscribe/Unsubscribe

- (void)updateSubscriptionToTopic:(NSString *)topic
                        withToken:(NSString *)token
                          options:(NSDictionary *)options
                     shouldDelete:(BOOL)shouldDelete
                          handler:(FIRMessagingTopicOperationCompletion)handler {
  _FIRMessagingDevAssert(handler, @"Invalid nil handler");

  if ([self tryToLoadValidCheckinInfo]) {
    [self doUpdateSubscriptionForTopic:topic
                                 token:token
                               options:options
                          shouldDelete:shouldDelete
                            completion:handler];

  } else {
    FIRMessagingLoggerDebug(kFIRMessagingMessageCodeRegistrar000,
                            @"Device check in error, no auth credentials found");
    NSError *error = [NSError errorWithFCMErrorCode:kFIRMessagingErrorCodeMissingDeviceID];
    handler(error);
  }
}

- (void)cancelAllRequests {
  self.stopAllSubscriptions = YES;
  [self.pubsubRegistrar stopAllSubscriptionRequests];
}

#pragma mark - Private

- (void)doUpdateSubscriptionForTopic:(NSString *)topic
                               token:(NSString *)token
                             options:(NSDictionary *)options
                        shouldDelete:(BOOL)shouldDelete
                          completion:(FIRMessagingTopicOperationCompletion)completion {
  _FIRMessagingDevAssert([self.checkinService hasValidCheckinInfo],
                @"No valid checkin info found before subscribe");

  [self.pubsubRegistrar updateSubscriptionToTopic:topic
                                        withToken:token
                                          options:options
                                     shouldDelete:shouldDelete
                                          handler:completion];
}

@end