1 files changed, 89 insertions, 0 deletions
diff --git a/Firebase/Database/Core/View/FValueEventRegistration.m b/Firebase/Database/Core/View/FValueEventRegistration.m
new file mode 100644
index 0000000..d351a4b
--- /dev/null
+++ b/Firebase/Database/Core/View/FValueEventRegistration.m
@@ -0,0 +1,89 @@
+/*
+ * 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 "FValueEventRegistration.h"
+#import "FIRDatabaseQuery_Private.h"
+#import "FQueryParams.h"
+#import "FQuerySpec.h"
+#import "FIRDataSnapshot_Private.h"
+#import "FCancelEvent.h"
+#import "FDataEvent.h"
+
+@interface FValueEventRegistration ()
+@property (nonatomic, strong) FRepo* repo;
+@property (nonatomic, copy, readwrite) fbt_void_datasnapshot callback;
+@property (nonatomic, copy, readwrite) fbt_void_nserror cancelCallback;
+@property (nonatomic, readwrite) FIRDatabaseHandle handle;
+@end
+
+@implementation FValueEventRegistration
+
+- (id) initWithRepo:(FRepo *)repo
+             handle:(FIRDatabaseHandle)fHandle
+           callback:(fbt_void_datasnapshot)callbackBlock
+     cancelCallback:(fbt_void_nserror)cancelCallbackBlock {
+    self = [super init];
+    if (self) {
+        self.repo = repo;
+        self.handle = fHandle;
+        self.callback = callbackBlock;
+        self.cancelCallback = cancelCallbackBlock;
+    }
+    return self;
+}
+
+- (BOOL) responseTo:(FIRDataEventType)eventType {
+    return eventType == FIRDataEventTypeValue;
+}
+
+- (FDataEvent *) createEventFrom:(FChange *)change query:(FQuerySpec *)query {
+    FIRDatabaseReference *ref = [[FIRDatabaseReference alloc] initWithRepo:self.repo path:query.path];
+    FIRDataSnapshot *snapshot = [[FIRDataSnapshot alloc] initWithRef:ref indexedNode:change.indexedNode];
+    FDataEvent *eventData = [[FDataEvent alloc] initWithEventType:FIRDataEventTypeValue eventRegistration:self
+                                                     dataSnapshot:snapshot];
+    return eventData;
+}
+
+- (void) fireEvent:(id <FEvent>)event queue:(dispatch_queue_t)queue {
+    if ([event isCancelEvent]) {
+        FCancelEvent *cancelEvent = event;
+        FFLog(@"I-RDB065001", @"Raising cancel value event on %@", event.path);
+        NSAssert(self.cancelCallback != nil, @"Raising a cancel event on a listener with no cancel callback");
+        dispatch_async(queue, ^{
+            self.cancelCallback(cancelEvent.error);
+        });
+    } else if (self.callback != nil) {
+        FDataEvent *dataEvent = event;
+        FFLog(@"I-RDB065002", @"Raising value event on %@", dataEvent.snapshot.key);
+        dispatch_async(queue, ^{
+            self.callback(dataEvent.snapshot);
+        });
+    }
+}
+
+- (FCancelEvent *) createCancelEventFromError:(NSError *)error path:(FPath *)path {
+    if (self.cancelCallback != nil) {
+        return [[FCancelEvent alloc] initWithEventRegistration:self error:error path:path];
+    } else {
+        return nil;
+    }
+}
+
+- (BOOL) matches:(id<FEventRegistration>)other {
+    return self.handle == NSNotFound || other.handle == NSNotFound || self.handle == other.handle;
+}
+
+@end