--- /dev/null
+/*
+ * 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 <Foundation/Foundation.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+/**
+ * @related FIRMessaging
+ *
+ * The completion handler invoked when the registration token returns.
+ * If the call fails we return the appropriate `error code`, described by
+ * `FIRMessagingError`.
+ *
+ * @param FCMToken The valid registration token returned by FCM.
+ * @param error The error describing why a token request failed. The error code
+ * will match a value from the FIRMessagingError enumeration.
+ */
+typedef void(^FIRMessagingFCMTokenFetchCompletion)(NSString * _Nullable FCMToken,
+ NSError * _Nullable error)
+ NS_SWIFT_NAME(MessagingFCMTokenFetchCompletion);
+
+
+/**
+ * @related FIRMessaging
+ *
+ * The completion handler invoked when the registration token deletion request is
+ * completed. If the call fails we return the appropriate `error code`, described
+ * by `FIRMessagingError`.
+ *
+ * @param error The error describing why a token deletion failed. The error code
+ * will match a value from the FIRMessagingError enumeration.
+ */
+typedef void(^FIRMessagingDeleteFCMTokenCompletion)(NSError * _Nullable error)
+ NS_SWIFT_NAME(MessagingDeleteFCMTokenCompletion);
+
+/**
+ * Callback to invoke once the HTTP call to FIRMessaging backend for updating
+ * subscription finishes.
+ *
+ * @param error The error which occurred while updating the subscription topic
+ * on the FIRMessaging server. This will be nil in case the operation
+ * was successful, or if the operation was cancelled.
+ */
+typedef void (^FIRMessagingTopicOperationCompletion)(NSError *_Nullable error);
+
+/**
+ * The completion handler invoked once the data connection with FIRMessaging is
+ * established. The data connection is used to send a continous stream of
+ * data and all the FIRMessaging data notifications arrive through this connection.
+ * Once the connection is established we invoke the callback with `nil` error.
+ * Correspondingly if we get an error while trying to establish a connection
+ * we invoke the handler with an appropriate error object and do an
+ * exponential backoff to try and connect again unless successful.
+ *
+ * @param error The error object if any describing why the data connection
+ * to FIRMessaging failed.
+ */
+typedef void(^FIRMessagingConnectCompletion)(NSError * __nullable error)
+ NS_SWIFT_NAME(MessagingConnectCompletion)
+ __deprecated_msg("Please listen for the FIRMessagingConnectionStateChangedNotification "
+ "NSNotification instead.");
+
+#if defined(__IPHONE_10_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_10_0
+/**
+ * Notification sent when the upstream message has been delivered
+ * successfully to the server. The notification object will be the messageID
+ * of the successfully delivered message.
+ */
+FOUNDATION_EXPORT const NSNotificationName FIRMessagingSendSuccessNotification
+ NS_SWIFT_NAME(MessagingSendSuccess);
+
+/**
+ * Notification sent when the upstream message was failed to be sent to the
+ * server. The notification object will be the messageID of the failed
+ * message. The userInfo dictionary will contain the relevant error
+ * information for the failure.
+ */
+FOUNDATION_EXPORT const NSNotificationName FIRMessagingSendErrorNotification
+ NS_SWIFT_NAME(MessagingSendError);
+
+/**
+ * Notification sent when the Firebase messaging server deletes pending
+ * messages due to exceeded storage limits. This may occur, for example, when
+ * the device cannot be reached for an extended period of time.
+ *
+ * It is recommended to retrieve any missing messages directly from the
+ * server.
+ */
+FOUNDATION_EXPORT const NSNotificationName FIRMessagingMessagesDeletedNotification
+ NS_SWIFT_NAME(MessagingMessagesDeleted);
+
+/**
+ * Notification sent when Firebase Messaging establishes or disconnects from
+ * an FCM socket connection. You can query the connection state in this
+ * notification by checking the `isDirectChannelEstablished` property of FIRMessaging.
+ */
+FOUNDATION_EXPORT const NSNotificationName FIRMessagingConnectionStateChangedNotification
+ NS_SWIFT_NAME(MessagingConnectionStateChanged);
+
+/**
+ * Notification sent when the FCM registration token has been refreshed. Please use the
+ * FIRMessaging delegate method `messaging:didReceiveRegistrationToken:` to receive current and
+ * updated tokens.
+ */
+FOUNDATION_EXPORT const NSNotificationName
+ FIRMessagingRegistrationTokenRefreshedNotification
+ NS_SWIFT_NAME(MessagingRegistrationTokenRefreshed);
+#else
+/**
+ * Notification sent when the upstream message has been delivered
+ * successfully to the server. The notification object will be the messageID
+ * of the successfully delivered message.
+ */
+FOUNDATION_EXPORT NSString *const FIRMessagingSendSuccessNotification
+ NS_SWIFT_NAME(MessagingSendSuccessNotification);
+
+/**
+ * Notification sent when the upstream message was failed to be sent to the
+ * server. The notification object will be the messageID of the failed
+ * message. The userInfo dictionary will contain the relevant error
+ * information for the failure.
+ */
+FOUNDATION_EXPORT NSString *const FIRMessagingSendErrorNotification
+ NS_SWIFT_NAME(MessagingSendErrorNotification);
+
+/**
+ * Notification sent when the Firebase messaging server deletes pending
+ * messages due to exceeded storage limits. This may occur, for example, when
+ * the device cannot be reached for an extended period of time.
+ *
+ * It is recommended to retrieve any missing messages directly from the
+ * server.
+ */
+FOUNDATION_EXPORT NSString *const FIRMessagingMessagesDeletedNotification
+ NS_SWIFT_NAME(MessagingMessagesDeletedNotification);
+
+/**
+ * Notification sent when Firebase Messaging establishes or disconnects from
+ * an FCM socket connection. You can query the connection state in this
+ * notification by checking the `isDirectChannelEstablished` property of FIRMessaging.
+ */
+FOUNDATION_EXPORT NSString *const FIRMessagingConnectionStateChangedNotification
+ NS_SWIFT_NAME(MessagingConnectionStateChangedNotification);
+
+/**
+ * Notification sent when the FCM registration token has been refreshed. Please use the
+ * FIRMessaging delegate method `messaging:didReceiveRegistrationToken:` to receive current and
+ * updated tokens.
+ */
+FOUNDATION_EXPORT NSString *const FIRMessagingRegistrationTokenRefreshedNotification
+ NS_SWIFT_NAME(MessagingRegistrationTokenRefreshedNotification);
+#endif // defined(__IPHONE_10_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_10_0
+
+/**
+ * @enum FIRMessagingError
+ */
+typedef NS_ENUM(NSUInteger, FIRMessagingError) {
+ /// Unknown error.
+ FIRMessagingErrorUnknown = 0,
+
+ /// FIRMessaging couldn't validate request from this client.
+ FIRMessagingErrorAuthentication = 1,
+
+ /// InstanceID service cannot be accessed.
+ FIRMessagingErrorNoAccess = 2,
+
+ /// Request to InstanceID backend timed out.
+ FIRMessagingErrorTimeout = 3,
+
+ /// No network available to reach the servers.
+ FIRMessagingErrorNetwork = 4,
+
+ /// Another similar operation in progress, bailing this one.
+ FIRMessagingErrorOperationInProgress = 5,
+
+ /// Some parameters of the request were invalid.
+ FIRMessagingErrorInvalidRequest = 7,
+} NS_SWIFT_NAME(MessagingError);
+
+/// Status for the downstream message received by the app.
+typedef NS_ENUM(NSInteger, FIRMessagingMessageStatus) {
+ /// Unknown status.
+ FIRMessagingMessageStatusUnknown,
+ /// New downstream message received by the app.
+ FIRMessagingMessageStatusNew,
+} NS_SWIFT_NAME(MessagingMessageStatus);
+
+/**
+ * The APNS token type for the app. If the token type is set to `UNKNOWN`
+ * Firebase Messaging will implicitly try to figure out what the actual token type
+ * is from the provisioning profile.
+ * Unless you really need to specify the type, you should use the `APNSToken`
+ * property instead.
+ */
+typedef NS_ENUM(NSInteger, FIRMessagingAPNSTokenType) {
+ /// Unknown token type.
+ FIRMessagingAPNSTokenTypeUnknown,
+ /// Sandbox token type.
+ FIRMessagingAPNSTokenTypeSandbox,
+ /// Production token type.
+ FIRMessagingAPNSTokenTypeProd,
+} NS_SWIFT_NAME(MessagingAPNSTokenType);
+
+/// Information about a downstream message received by the app.
+NS_SWIFT_NAME(MessagingMessageInfo)
+@interface FIRMessagingMessageInfo : NSObject
+
+/// The status of the downstream message
+@property(nonatomic, readonly, assign) FIRMessagingMessageStatus status;
+
+@end
+
+/**
+ * A remote data message received by the app via FCM (not just the APNs interface).
+ *
+ * This is only for devices running iOS 10 or above. To support devices running iOS 9 or below, use
+ * the local and remote notifications handlers defined in UIApplicationDelegate protocol.
+ */
+NS_SWIFT_NAME(MessagingRemoteMessage)
+@interface FIRMessagingRemoteMessage : NSObject
+
+/// The downstream message received by the application.
+@property(nonatomic, readonly, strong) NSDictionary *appData;
+@end
+
+@class FIRMessaging;
+/**
+ * A protocol to handle token update or data message delivery from FCM.
+ *
+ */
+NS_SWIFT_NAME(MessagingDelegate)
+@protocol FIRMessagingDelegate <NSObject>
+
+@optional
+/// This method will be called once a token is available, or has been refreshed. Typically it
+/// will be called once per app start, but may be called more often, if token is invalidated or
+/// updated. In this method, you should perform operations such as:
+///
+/// * Uploading the FCM token to your application server, so targeted notifications can be sent.
+///
+/// * Subscribing to any topics.
+- (void)messaging:(FIRMessaging *)messaging
+ didReceiveRegistrationToken:(NSString *)fcmToken
+ NS_SWIFT_NAME(messaging(_:didReceiveRegistrationToken:));
+
+/// This method is called on iOS 10 devices to handle data messages received via FCM through its
+/// direct channel (not via APNS). For iOS 9 and below, the FCM data message is delivered via the
+/// UIApplicationDelegate's -application:didReceiveRemoteNotification: method.
+- (void)messaging:(FIRMessaging *)messaging
+ didReceiveMessage:(FIRMessagingRemoteMessage *)remoteMessage
+ NS_SWIFT_NAME(messaging(_:didReceive:))
+ __IOS_AVAILABLE(10.0);
+
+@end
+
+/**
+ * Firebase Messaging lets you reliably deliver messages at no cost.
+ *
+ * To send or receive messages, the app must get a
+ * registration token from FIRInstanceID. This token authorizes an
+ * app server to send messages to an app instance.
+ *
+ * In order to receive FIRMessaging messages, declare `application:didReceiveRemoteNotification:`.
+ */
+NS_SWIFT_NAME(Messaging)
+@interface FIRMessaging : NSObject
+
+/**
+ * Delegate to handle FCM token refreshes, and remote data messages received via FCM for devices
+ * running iOS 10 or above.
+ */
+@property(nonatomic, weak, nullable) id<FIRMessagingDelegate> delegate;
+
+/**
+ * When set to `YES`, Firebase Messaging will automatically establish a socket-based, direct
+ * channel to the FCM server. Enable this only if you are sending upstream messages or
+ * receiving non-APNS, data-only messages in foregrounded apps.
+ * Default is `NO`.
+ */
+@property(nonatomic) BOOL shouldEstablishDirectChannel;
+
+/**
+ * Returns `YES` if the direct channel to the FCM server is active, and `NO` otherwise.
+ */
+@property(nonatomic, readonly) BOOL isDirectChannelEstablished;
+
+/**
+ * FIRMessaging
+ *
+ * @return An instance of FIRMessaging.
+ */
++ (instancetype)messaging NS_SWIFT_NAME(messaging());
+
+/**
+ * Unavailable. Use +messaging instead.
+ */
+- (instancetype)init __attribute__((unavailable("Use +messaging instead.")));
+
+#pragma mark - APNS
+
+/**
+ * This property is used to set the APNS Token received by the application delegate.
+ *
+ * FIRMessaging uses method swizzling to ensure that the APNS token is set
+ * automatically. However, if you have disabled swizzling by setting
+ * `FirebaseAppDelegateProxyEnabled` to `NO` in your app's
+ * Info.plist, you should manually set the APNS token in your application
+ * delegate's `-application:didRegisterForRemoteNotificationsWithDeviceToken:`
+ * method.
+ *
+ * If you would like to set the type of the APNS token, rather than relying on
+ * automatic detection, see: `-setAPNSToken:type:`.
+ */
+@property(nonatomic, copy, nullable) NSData *APNSToken NS_SWIFT_NAME(apnsToken);
+
+/**
+ * Set APNS token for the application. This APNS token will be used to register
+ * with Firebase Messaging using `FCMToken` or
+ * `tokenWithAuthorizedEntity:scope:options:handler`.
+ *
+ * @param apnsToken The APNS token for the application.
+ * @param type The type of APNS token. Debug builds should use
+ * FIRMessagingAPNSTokenTypeSandbox. Alternatively, you can supply
+ * FIRMessagingAPNSTokenTypeUnknown to have the type automatically
+ * detected based on your provisioning profile.
+ */
+- (void)setAPNSToken:(NSData *)apnsToken type:(FIRMessagingAPNSTokenType)type;
+
+#pragma mark - FCM Tokens
+
+/**
+ * Is Firebase Messaging token auto generation enabled? If this flag is disabled,
+ * Firebase Messaging will not generate token automatically for message delivery.
+ *
+ * If this flag is disabled, Firebase Messaging does not generate new tokens automatically for
+ * message delivery. If this flag is enabled, FCM generates a registration token on application
+ * start when there is no existing valid token. FCM also generates a new token when an existing
+ * token is deleted.
+ *
+ * This setting is persisted, and is applied on future
+ * invocations of your application. Once explicitly set, it overrides any
+ * settings in your Info.plist.
+ *
+ * By default, FCM automatic initialization is enabled. If you need to change the
+ * default (for example, because you want to prompt the user before getting token)
+ * set FirebaseMessagingAutoInitEnabled to false in your application's Info.plist.
+ */
+@property(nonatomic, assign, getter=isAutoInitEnabled) BOOL autoInitEnabled;
+
+/**
+ * The FCM token is used to identify this device so that FCM can send notifications to it.
+ * It is associated with your APNS token when the APNS token is supplied, so that sending
+ * messages to the FCM token will be delivered over APNS.
+ *
+ * The FCM token is sometimes refreshed automatically. In your FIRMessaging delegate, the
+ * delegate method `messaging:didReceiveRegistrationToken:` will be called once a token is
+ * available, or has been refreshed. Typically it should be called once per app start, but
+ * may be called more often, if token is invalidated or updated.
+ *
+ * Once you have an FCM token, you should send it to your application server, so it can use
+ * the FCM token to send notifications to your device.
+ */
+@property(nonatomic, readonly, nullable) NSString *FCMToken NS_SWIFT_NAME(fcmToken);
+
+
+/**
+ * Retrieves an FCM registration token for a particular Sender ID. This can be used to allow
+ * multiple senders to send notifications to the same device. By providing a different Sender
+ * ID than your default when fetching a token, you can create a new FCM token which you can
+ * give to a different sender. Both tokens will deliver notifications to your device, and you
+ * can revoke a token when you need to.
+ *
+ * This registration token is not cached by FIRMessaging. FIRMessaging should have an APNS
+ * token set before calling this to ensure that notifications can be delivered via APNS using
+ * this FCM token. You may re-retrieve the FCM token once you have the APNS token set, to
+ * associate it with the FCM token. The default FCM token is automatically associated with
+ * the APNS token, if the APNS token data is available.
+ *
+ * @param senderID The Sender ID for a particular Firebase project.
+ * @param completion The completion handler to handle the token request.
+ */
+- (void)retrieveFCMTokenForSenderID:(NSString *)senderID
+ completion:(FIRMessagingFCMTokenFetchCompletion)completion
+ NS_SWIFT_NAME(retrieveFCMToken(forSenderID:completion:));
+
+
+/**
+ * Invalidates an FCM token for a particular Sender ID. That Sender ID cannot no longer send
+ * notifications to that FCM token.
+ *
+ * @param senderID The senderID for a particular Firebase project.
+ * @param completion The completion handler to handle the token deletion.
+ */
+- (void)deleteFCMTokenForSenderID:(NSString *)senderID
+ completion:(FIRMessagingDeleteFCMTokenCompletion)completion
+ NS_SWIFT_NAME(deleteFCMToken(forSenderID:completion:));
+
+
+#pragma mark - Connect
+
+/**
+ * Create a FIRMessaging data connection which will be used to send the data notifications
+ * sent by your server. It will also be used to send ACKS and other messages based
+ * on the FIRMessaging ACKS and other messages based on the FIRMessaging protocol.
+ *
+ *
+ * @param handler The handler to be invoked once the connection is established.
+ * If the connection fails we invoke the handler with an
+ * appropriate error code letting you know why it failed. At
+ * the same time, FIRMessaging performs exponential backoff to retry
+ * establishing a connection and invoke the handler when successful.
+ */
+- (void)connectWithCompletion:(FIRMessagingConnectCompletion)handler
+ NS_SWIFT_NAME(connect(handler:))
+ __deprecated_msg("Please use the shouldEstablishDirectChannel property instead.");
+
+/**
+ * Disconnect the current FIRMessaging data connection. This stops any attempts to
+ * connect to FIRMessaging. Calling this on an already disconnected client is a no-op.
+ *
+ * Call this before `teardown` when your app is going to the background.
+ * Since the FIRMessaging connection won't be allowed to live when in the background, it is
+ * prudent to close the connection.
+ */
+- (void)disconnect
+ __deprecated_msg("Please use the shouldEstablishDirectChannel property instead.");
+
+#pragma mark - Topics
+
+/**
+ * Asynchronously subscribes to a topic.
+ *
+ * @param topic The name of the topic, for example, @"sports".
+ */
+- (void)subscribeToTopic:(NSString *)topic NS_SWIFT_NAME(subscribe(toTopic:));
+
+/**
+ * Asynchronously subscribe to the provided topic, retrying on failure.
+ *
+ * @param topic The topic name to subscribe to, for example, @"sports".
+ * @param completion The completion that is invoked once the subscribe call ends.
+ * In case of success, nil error is returned. Otherwise, an
+ * appropriate error object is returned.
+ */
+- (void)subscribeToTopic:(nonnull NSString *)topic
+ completion:(nullable FIRMessagingTopicOperationCompletion)completion;
+
+/**
+ * Asynchronously unsubscribe from a topic.
+ *
+ * @param topic The name of the topic, for example @"sports".
+ */
+- (void)unsubscribeFromTopic:(NSString *)topic NS_SWIFT_NAME(unsubscribe(fromTopic:));
+
+/**
+ * Asynchronously unsubscribe from the provided topic, retrying on failure.
+ *
+ * @param topic The topic name to unsubscribe from, for example @"sports".
+ * @param completion The completion that is invoked once the unsubscribe call ends.
+ * In case of success, nil error is returned. Otherwise, an
+ * appropriate error object is returned.
+ */
+- (void)unsubscribeFromTopic:(nonnull NSString *)topic
+ completion:(nullable FIRMessagingTopicOperationCompletion)completion;
+
+#pragma mark - Upstream
+
+/**
+ * Sends an upstream ("device to cloud") message.
+ *
+ * The message is queued if we don't have an active connection.
+ * You can only use the upstream feature if your FCM implementation
+ * uses the XMPP server protocol.
+ *
+ * @param message Key/Value pairs to be sent. Values must be String, any
+ * other type will be ignored.
+ * @param receiver A string identifying the receiver of the message. For FCM
+ * project IDs the value is `SENDER_ID@gcm.googleapis.com`.
+ * @param messageID The ID of the message. This is generated by the application. It
+ * must be unique for each message generated by this application.
+ * It allows error callbacks and debugging, to uniquely identify
+ * each message.
+ * @param ttl The time to live for the message. In case we aren't able to
+ * send the message before the TTL expires we will send you a
+ * callback. If 0, we'll attempt to send immediately and return
+ * an error if we're not connected. Otherwise, the message will
+ * be queued. As for server-side messages, we don't return an error
+ * if the message has been dropped because of TTL; this can happen
+ * on the server side, and it would require extra communication.
+ */
+- (void)sendMessage:(NSDictionary *)message
+ to:(NSString *)receiver
+ withMessageID:(NSString *)messageID
+ timeToLive:(int64_t)ttl;
+
+#pragma mark - Analytics
+
+/**
+ * Use this to track message delivery and analytics for messages, typically
+ * when you receive a notification in `application:didReceiveRemoteNotification:`.
+ * However, you only need to call this if you set the `FirebaseAppDelegateProxyEnabled`
+ * flag to `NO` in your Info.plist. If `FirebaseAppDelegateProxyEnabled` is either missing
+ * or set to `YES` in your Info.plist, the library will call this automatically.
+ *
+ * @param message The downstream message received by the application.
+ *
+ * @return Information about the downstream message.
+ */
+- (FIRMessagingMessageInfo *)appDidReceiveMessage:(NSDictionary *)message;
+
+@end
+
+NS_ASSUME_NONNULL_END