1 files changed, 49 insertions, 0 deletions
diff --git a/Firebase/Database/Snapshot/FIndexedNode.h b/Firebase/Database/Snapshot/FIndexedNode.h
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+++ b/Firebase/Database/Snapshot/FIndexedNode.h
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+/*
+ * 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 "FNode.h"
+#import "FIndex.h"
+#import "FNamedNode.h"
+
+/**
+ * Represents a node together with an index. The index and node are updated in unison. In the case where the index
+ * does not affect the ordering (i.e. the ordering is identical to the key ordering) this class uses a fallback index
+ * to save memory. Everything operating on the index must special case the fallback index.
+ */
+@interface FIndexedNode : NSObject
+
+@property (nonatomic, strong, readonly) id<FNode> node;
+
++ (FIndexedNode *)indexedNodeWithNode:(id<FNode>)node;
++ (FIndexedNode *)indexedNodeWithNode:(id<FNode>)node index:(id<FIndex>)index;
+
+- (BOOL)hasIndex:(id<FIndex>)index;
+- (FIndexedNode *)updateChild:(NSString *)key withNewChild:(id<FNode>)newChildNode;
+- (FIndexedNode *)updatePriority:(id<FNode>)priority;
+
+- (FNamedNode *)firstChild;
+- (FNamedNode *)lastChild;
+
+- (NSString *)predecessorForChildKey:(NSString *)childKey childNode:(id<FNode>)childNode index:(id<FIndex>)index;
+
+- (void)enumerateChildrenReverse:(BOOL)reverse usingBlock:(void (^)(NSString *key, id<FNode> node, BOOL *stop))block;
+
+- (NSEnumerator *)childEnumerator;
+
+@end