grpc/src/objective-c/RxLibrary/GRXWriteable.m

/*
 *
 * Copyright 2015, Google Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#import "GRXWriteable.h"

@implementation GRXWriteable {
  GRXValueHandler _valueHandler;
  GRXCompletionHandler _completionHandler;
}

+ (instancetype)writeableWithSingleValueHandler:(GRXSingleValueHandler)handler {
  if (!handler) {
    return [[self alloc] init];
  }
  return [[self alloc] initWithValueHandler:^(id value) {
    handler(value, nil);
  } completionHandler:^(NSError *errorOrNil) {
    if (errorOrNil) {
      handler(nil, errorOrNil);
    }
  }];
}

+ (instancetype)writeableWithStreamHandler:(GRXStreamHandler)handler {
  if (!handler) {
    return [[self alloc] init];
  }
  return [[self alloc] initWithValueHandler:^(id value) {
    handler(NO, value, nil);
  } completionHandler:^(NSError *errorOrNil) {
    handler(YES, nil, errorOrNil);
  }];
}

- (instancetype)init {
  return [self initWithValueHandler:nil completionHandler:nil];
}

// Designated initializer
- (instancetype)initWithValueHandler:(GRXValueHandler)valueHandler
                   completionHandler:(GRXCompletionHandler)completionHandler {
  if ((self = [super init])) {
    _valueHandler = valueHandler;
    _completionHandler = completionHandler;
  }
  return self;
}

- (void)didReceiveValue:(id)value {
  if (_valueHandler) {
    _valueHandler(value);
  }
}

- (void)didFinishWithError:(NSError *)errorOrNil {
  if (_completionHandler) {
    _completionHandler(errorOrNil);
  }
}
@end