components/Snackbar/src/MDCSnackbarMessage.m

/*
 Copyright 2016-present the Material Components for iOS authors. All Rights Reserved.

 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 "MDCSnackbarMessage.h"
#import "MDCSnackbarMessageView.h"
#import "private/MDCSnackbarMessageInternal.h"

static const NSTimeInterval kDefaultDuration = 4.0f;

const NSTimeInterval MDCSnackbarMessageDurationMax = 10;
NSString *const MDCSnackbarMessageBoldAttributeName = @"MDCSnackbarMessageBoldAttributeName";

@interface MDCSnackbarMessage ()

@property(nonatomic, readonly, strong) dispatch_queue_t targetQueue;

@property(nonatomic, assign) BOOL hasSetTextAlignment;

@end

@implementation MDCSnackbarMessage

@synthesize accessibilityIdentifier;
@dynamic text;

+ (instancetype)messageWithText:(NSString *)text {
  MDCSnackbarMessage *message = [[MDCSnackbarMessage alloc] init];
  message.text = text;
  return message;
}

+ (instancetype)messageWithAttributedText:(NSAttributedString *)attributedText {
  MDCSnackbarMessage *message = [[MDCSnackbarMessage alloc] init];
  message.attributedText = attributedText;
  return message;
}

- (instancetype)init {
  self = [super init];
  if (self) {
    _duration = kDefaultDuration;
  }
  return self;
}

- (Class)viewClass {
  return [MDCSnackbarMessageView class];
}

- (instancetype)copyWithZone:(NSZone *)zone {
  MDCSnackbarMessage *copy = [[[self class] alloc] init];
  copy.attributedText = self.attributedText;
  copy.duration = self.duration;
  copy.category = self.category;
  copy.accessibilityLabel = self.accessibilityLabel;
  copy.buttonTextColor = self.buttonTextColor;
  copy.highlightedButtonTextColor = self.highlightedButtonTextColor;

  // Unfortunately there's not really a concept of 'copying' a block (in the same way you would copy
  // a string, for example). A block's pointer is immutable once it is created and copied to the
  // heap, so we're pretty safe just using the same block.
  copy.completionHandler = self.completionHandler;
  copy.action = self.action;

  return copy;
}

- (dispatch_queue_t)targetQueue {
  return dispatch_get_main_queue();
}

#pragma mark Text

- (void)setText:(NSString *)text {
  self.attributedText = [[NSAttributedString alloc] initWithString:[text copy]];
}

- (NSString *)text {
  return [self.attributedText string];
}

#pragma mark - Duration

- (void)setDuration:(NSTimeInterval)duration {
  NSAssert(duration <= MDCSnackbarMessageDurationMax,
           @"Duration %g is longer than the maximum allowed: %g.", duration,
           MDCSnackbarMessageDurationMax);
  _duration = MIN(MDCSnackbarMessageDurationMax, duration);
}

#pragma mark - A11y

- (NSString *)voiceNotificationText {
  if ([self.accessibilityLabel length]) {
    return self.accessibilityLabel;
  } else {
    return self.text;
  }
}

#pragma mark - Internal

- (void)executeCompletionHandlerWithUserInteraction:(BOOL)userInteraction
                                         completion:(void (^)(void))completion {
  if (self.completionHandler) {
    dispatch_async(self.targetQueue, ^{
      self.completionHandler(userInteraction);
      if (completion) {
        completion();
      }
    });
  } else {
    if (completion) {
      completion();
    }
  }
}

- (void)executeActionHandler:(MDCSnackbarMessageAction *)action
                  completion:(void (^)(void))completion {
  if (!action || !action.handler) {
    if (completion) {
      completion();
    }
    return;
  }

  // Fire off the action handler.
  dispatch_async(self.targetQueue, ^{
    action.handler();
    if (completion) {
      completion();
    }
  });
}

@end

@implementation MDCSnackbarMessageAction

@synthesize accessibilityIdentifier;

- (instancetype)copyWithZone:(NSZone *)zone {
  MDCSnackbarMessageAction *copy = [[[self class] alloc] init];
  copy.title = self.title;
  copy.handler = self.handler;  // See the comment on @c completionHandler above.
  copy.accessibilityIdentifier = self.accessibilityIdentifier;

  return copy;
}

@end