1/*
2 *
3 * Copyright 2016 gRPC authors.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 */
18
19#import "GRXImmediateSingleWriter.h"
20
21@implementation GRXImmediateSingleWriter {
22  id _value;
23  id<GRXWriteable> _writeable;
24}
25
26@synthesize state = _state;
27
28- (instancetype)initWithValue:(id)value {
29  if (self = [super init]) {
30    _value = value;
31    _state = GRXWriterStateNotStarted;
32  }
33  return self;
34}
35
36+ (GRXWriter *)writerWithValue:(id)value {
37  return [[self alloc] initWithValue:value];
38}
39
40- (void)startWithWriteable:(id<GRXWriteable>)writeable {
41  _state = GRXWriterStateStarted;
42  _writeable = writeable;
43  [writeable writeValue:_value];
44  [self finish];
45}
46
47- (void)finish {
48  _state = GRXWriterStateFinished;
49  _value = nil;
50  id<GRXWriteable> writeable = _writeable;
51  _writeable = nil;
52  [writeable writesFinishedWithError:nil];
53}
54
55// Overwrite the setter to disallow manual state transition. The getter
56// of _state is synthesized.
57- (void)setState:(GRXWriterState)newState {
58  // Manual state transition is not allowed
59  return;
60}
61
62// Overrides [requestWriter(Transformations):map:] for Protocol Buffers
63// encoding.
64// We need the return value of this map to be a GRXImmediateSingleWriter but
65// the original \a map function returns a new Writer of another type. So we
66// need to override this function here.
67- (GRXWriter *)map:(id (^)(id))map {
68  // Since _value is available when creating the object, we can simply
69  // apply the map and store the output.
70  _value = map(_value);
71  return self;
72}
73
74@end
75