notification.m

//
//  PJNotificationCenter.m
//  NotificationSample
//
//  Created by Peter Foti on 6/21/16.
//  Copyright © 2016 Peter Foti. All rights reserved.
//

#import "PJNotificationCenter.h"
#import "PJNotificationKey.h"

@interface PJNotificationCenter ()

@property (strong, nonatomic) NSMutableDictionary *observerDict;

@end

@implementation PJNotificationCenter

- (NSMutableDictionary *)observerDict
{
    return _observerDict = _observerDict ?: [NSMutableDictionary new];
}

- (void)pj_addObserverForName:(NSString *)name object:(id)obj usingBlock:(void (^)(NSNotification * _Nonnull))block
{
    PJNotificationKey *key = [PJNotificationKey keyForName:name object:obj];
   
    NSMutableSet *observerBlocks = self.observerDict[key];
    
    if (!observerBlocks) {
        observerBlocks = [NSMutableSet new];
        self.observerDict[key] = observerBlocks;
    }
    
    [observerBlocks addObject:[block copy]];
}

- (void)pj_postNotificationName:(NSString *)aName object:(id)anObject
{
    PJNotificationKey *key = [PJNotificationKey keyForName:aName object:anObject];
    
    NSMutableSet *observerBlocks = self.observerDict[key];
    
    NSNotification *note = [NSNotification notificationWithName:aName object:anObject];
    
    for (void (^block)(NSNotification *) in observerBlocks) {
        block(note);
    }
}

@end

//
//  PJNotificationKey.m
//  NotificationSample
//
//  Created by Peter Foti on 6/21/16.
//  Copyright © 2016 Peter Foti. All rights reserved.
//

#import "PJNotificationKey.h"

@interface PJNotificationKey ()

@property (copy, nonatomic) NSString *name;
@property (weak, nonatomic) id object;
@end

@implementation PJNotificationKey

+ (PJNotificationKey *)keyForName:(NSString *)name object:(id)object
{
    return [[self alloc] initWithName:name object:object];
}

- (id)copyWithZone:(NSZone *)zone
{
    return self;
}

- (NSUInteger)hash
{
    return [self.name hash] ^ [self.object hash];
}

- (BOOL)isEqual:(id)object
{
    if ([object isKindOfClass:[self class]]) {
        PJNotificationKey *key = (PJNotificationKey *)object;
        if ([key.name isEqualToString:self.name] && [key.object isEqual:self.object]) {
            return YES;
        } else {
            return [object isEqual:self];
        }
    } else {
        return NO;
    }
}

- (id)initWithName:(NSString *)name object:(id)obj
{
    if (self = [self init]) {
        _name = name;
        _object = obj;
    }
    
    return self;
}

@end