//
//  MBIMUpdateQueue.m
//  kordophoned
//
//  Created by James Magahern on 11/16/18.
//  Copyright © 2018 James Magahern. All rights reserved.
//

#import "MBIMUpdateQueue.h"
#import "IMMessageItem+Encoded.h"
#import "IMChat+Encoded.h"

@interface MBIMUpdateItem (/*INTERNAL*/)
@property (nonatomic, assign) NSUInteger messageSequenceNumber;
@end

@implementation MBIMUpdateQueue {
    NSUInteger           _messageSequenceNumber;
    dispatch_queue_t     _accessQueue;
    NSMutableArray      *_consumers;
}

+ (instancetype)sharedInstance
{
    static MBIMUpdateQueue *sharedInstance = nil;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        sharedInstance = [[self alloc] init];
    });
    
    return sharedInstance;
}

- (instancetype)init
{
    self = [super init];
    if (self) {
        _accessQueue = dispatch_queue_create("net.buzzert.MBIMUpdateQueue", DISPATCH_QUEUE_SERIAL);
        _consumers = [[NSMutableArray alloc] init];
        _messageSequenceNumber = 0;
    }
    
    return self;
}

- (void)addConsumer:(MBIMUpdateConsumer)consumer
{
    __weak NSMutableArray *consumers = _consumers;
    dispatch_async(_accessQueue, ^{
        [consumers addObject:consumer];
    });
}

- (void)removeConsumer:(MBIMUpdateConsumer)consumer
{
    __weak NSMutableArray *consumers = _consumers;
    dispatch_async(_accessQueue, ^{
        [consumers removeObject:consumer];
    });
}

- (void)enqueueUpdateItem:(MBIMUpdateItem *)item
{
    _messageSequenceNumber++;
    item.messageSequenceNumber = _messageSequenceNumber;
    
    __weak NSMutableArray *consumers = _consumers;
    dispatch_async(_accessQueue, ^{
        for (MBIMUpdateConsumer consumer in consumers) {
            consumer(item);
        }
        
        [consumers removeAllObjects];
    });
}

@end

@implementation MBIMUpdateItem
- (NSDictionary *)dictionaryRepresentation
{
    NSMutableDictionary *updateDict = [NSMutableDictionary dictionary];
    updateDict[@"messageSequenceNumber"] = @(_messageSequenceNumber);
    
    if ([self changedChat]) {
        updateDict[@"conversation"] = [[self changedChat] mbim_dictionaryRepresentation];
    }
    
    if ([self addedMessage]) {
        updateDict[@"message"] = [[self addedMessage] mbim_dictionaryRepresentation];
    }
    
    return updateDict;
}

@end