1 files changed, 118 insertions, 0 deletions
diff --git a/Firestore/Source/Remote/FSTWatchChange.h b/Firestore/Source/Remote/FSTWatchChange.h
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+++ b/Firestore/Source/Remote/FSTWatchChange.h
@@ -0,0 +1,118 @@
+/*
+ * 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>
+
+#import "FSTTypes.h"
+
+@class FSTDocumentKey;
+@class FSTExistenceFilter;
+@class FSTMaybeDocument;
+@class FSTSnapshotVersion;
+
+NS_ASSUME_NONNULL_BEGIN
+
+/**
+ * FSTWatchChange is the internal representation of the watcher API protocol buffers.
+ * This is an empty abstract class so that all the different kinds of changes can have a common
+ * base class.
+ */
+@interface FSTWatchChange : NSObject
+@end
+
+/**
+ * FSTDocumentWatchChange represents a changed document and a list of target ids to which this
+ * change applies. If the document has been deleted, the deleted document will be provided.
+ */
+@interface FSTDocumentWatchChange : FSTWatchChange
+
+- (instancetype)initWithUpdatedTargetIDs:(NSArray<NSNumber *> *)updatedTargetIDs
+                        removedTargetIDs:(NSArray<NSNumber *> *)removedTargetIDs
+                             documentKey:(FSTDocumentKey *)documentKey
+                                document:(nullable FSTMaybeDocument *)document
+    NS_DESIGNATED_INITIALIZER;
+
+- (instancetype)init NS_UNAVAILABLE;
+
+/** The new document applies to all of these targets. */
+@property(nonatomic, strong, readonly) NSArray<NSNumber *> *updatedTargetIDs;
+
+/** The new document is removed from all of these targets. */
+@property(nonatomic, strong, readonly) NSArray<NSNumber *> *removedTargetIDs;
+
+/** The key of the document for this change. */
+@property(nonatomic, strong, readonly) FSTDocumentKey *documentKey;
+
+/**
+ * The new document or DeletedDocument if it was deleted. Is null if the document went out of
+ * view without the server sending a new document.
+ */
+@property(nonatomic, strong, readonly, nullable) FSTMaybeDocument *document;
+
+@end
+
+/**
+ * An ExistenceFilterWatchChange applies to the targets and is required to verify the current client
+ * state against expected state sent from the server.
+ */
+@interface FSTExistenceFilterWatchChange : FSTWatchChange
+
++ (instancetype)changeWithFilter:(FSTExistenceFilter *)filter targetID:(FSTTargetID)targetID;
+
+- (instancetype)init NS_UNAVAILABLE;
+
+@property(nonatomic, strong, readonly) FSTExistenceFilter *filter;
+@property(nonatomic, assign, readonly) FSTTargetID targetID;
+@end
+
+/** FSTWatchTargetChangeState is the kind of change that happened to the watch target. */
+typedef NS_ENUM(NSInteger, FSTWatchTargetChangeState) {
+  FSTWatchTargetChangeStateNoChange,
+  FSTWatchTargetChangeStateAdded,
+  FSTWatchTargetChangeStateRemoved,
+  FSTWatchTargetChangeStateCurrent,
+  FSTWatchTargetChangeStateReset,
+};
+
+/** FSTWatchTargetChange is a change to a watch target. */
+@interface FSTWatchTargetChange : FSTWatchChange
+
+- (instancetype)initWithState:(FSTWatchTargetChangeState)state
+                    targetIDs:(NSArray<NSNumber *> *)targetIDs
+                  resumeToken:(NSData *)resumeToken
+                        cause:(nullable NSError *)cause NS_DESIGNATED_INITIALIZER;
+
+- (instancetype)init NS_UNAVAILABLE;
+
+/** What kind of change occurred to the watch target. */
+@property(nonatomic, assign, readonly) FSTWatchTargetChangeState state;
+
+/** The target IDs that were added/removed/set. */
+@property(nonatomic, strong, readonly) NSArray<NSNumber *> *targetIDs;
+
+/**
+ * An opaque, server-assigned token that allows watching a query to be resumed after disconnecting
+ * without retransmitting all the data that matches the query. The resume token essentially
+ * identifies a point in time from which the server should resume sending results.
+ */
+@property(nonatomic, strong, readonly) NSData *resumeToken;
+
+/** An RPC error indicating why the watch failed. */
+@property(nonatomic, strong, readonly, nullable) NSError *cause;
+
+@end
+
+NS_ASSUME_NONNULL_END