/*
 * Copyright (c) 2012-2014,2016 Apple Inc. All Rights Reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */

//
//  CKDKVSProxy.m
//  ckd-xpc
//

#import <Foundation/Foundation.h>

#import <utilities/debugging.h>
#import <os/activity.h>

#import "CKDKVSProxy.h"
#import "CKDPersistentState.h"
#import "CKDKVSStore.h"
#import "CKDSecuritydAccount.h"

#include <Security/SecureObjectSync/SOSARCDefines.h>
#include <utilities/SecCFWrappers.h>

#include "SOSCloudKeychainConstants.h"

#include <utilities/SecAKSWrappers.h>

/*
 The total space available in your app’s iCloud key-value storage is 1 MB.
 The maximum number of keys you can specify is 1024, and the size limit for
 each value associated with a key is 1 MB. So, for example, if you store a
 single large value of 1 MB for a single key, that consumes your total
 available storage. If you store 1 KB of data for each key, you can use
 1,000 key-value pairs.
 */

static const char *kStreamName = "com.apple.notifyd.matching";

static NSString *kKeyKeyParameterKeys = @"KeyParameterKeys";
static NSString *kKeyCircleKeys = @"CircleKeys";
static NSString *kKeyMessageKeys = @"MessageKeys";

static NSString *kKeyAlwaysKeys = @"AlwaysKeys";
static NSString *kKeyFirstUnlockKeys = @"FirstUnlockKeys";
static NSString *kKeyUnlockedKeys = @"UnlockedKeys";
static NSString *kKeyPendingKeys = @"PendingKeys";
static NSString *kKeyUnsentChangedKeys = @"unsentChangedKeys";
static NSString *kKeyUnlockNotificationRequested = @"unlockNotificationRequested";
static NSString *kKeySyncWithPeersPending = @"SyncWithPeersPending";
static NSString *kKeyEnsurePeerRegistration = @"EnsurePeerRegistration";
static NSString *kKeyDSID = @"DSID";
static NSString *kMonitorState = @"MonitorState";

static NSString *kMonitorPenaltyBoxKey = @"Penalty";
static NSString *kMonitorMessageKey = @"Message";
static NSString *kMonitorConsecutiveWrites = @"ConsecutiveWrites";
static NSString *kMonitorLastWriteTimestamp = @"LastWriteTimestamp";
static NSString *kMonitorMessageQueue = @"MessageQueue";
static NSString *kMonitorPenaltyTimer = @"PenaltyTimer";
static NSString *kMonitorDidWriteDuringPenalty = @"DidWriteDuringPenalty";

static NSString *kMonitorTimeTable = @"TimeTable";
static NSString *kMonitorFirstMinute = @"AFirstMinute";
static NSString *kMonitorSecondMinute = @"BSecondMinute";
static NSString *kMonitorThirdMinute = @"CThirdMinute";
static NSString *kMonitorFourthMinute = @"DFourthMinute";
static NSString *kMonitorFifthMinute = @"EFifthMinute";
static NSString *kMonitorWroteInTimeSlice = @"TimeSlice";
const CFStringRef kSOSKVSKeyParametersKey = CFSTR(">KeyParameters");
const CFStringRef kSOSKVSInitialSyncKey = CFSTR("^InitialSync");
const CFStringRef kSOSKVSAccountChangedKey = CFSTR("^AccountChanged");
const CFStringRef kSOSKVSRequiredKey = CFSTR("^Required");
const CFStringRef kSOSKVSOfficialDSIDKey = CFSTR("^OfficialDSID");

#define kSecServerKeychainChangedNotification "com.apple.security.keychainchanged"

static int max_penalty_timeout = 32;
static int seconds_per_minute = 60;

static const int64_t kMinSyncDelay = (NSEC_PER_MSEC * 500);         // 500ms minimum delay before a syncWithAllPeers call.
static const int64_t kMaxSyncDelay = (NSEC_PER_SEC * 5);            //   5s  maximun delay for a given request
static const int64_t kMinSyncInterval = (NSEC_PER_SEC * 15);        //  15s  minimum time between successive syncWithAllPeers calls.
static const int64_t kSyncTimerLeeway = (NSEC_PER_MSEC * 250);      // 250ms leeway for sync events.

static NSString* asNSString(NSObject* object) {
    return [object isKindOfClass:[NSString class]] ? (NSString*) object : nil;
}

@interface NSMutableDictionary (FindAndRemove)
-(NSObject*)extractObjectForKey:(NSString*)key;
@end

@implementation NSMutableDictionary (FindAndRemove)
-(NSObject*)extractObjectForKey:(NSString*)key {
    NSObject* result = [self objectForKey:key];
    [self removeObjectForKey: key];
    return result;
}
@end

@implementation UbiqitousKVSProxy

- (void)persistState
{
    [SOSPersistentState setRegisteredKeys:[self exportKeyInterests]];
}

+ (UbiqitousKVSProxy *) sharedKVSProxy
{
    static UbiqitousKVSProxy *sharedKVSProxy;
    if (!sharedKVSProxy) {
        static dispatch_once_t onceToken;
        dispatch_once(&onceToken, ^{
            sharedKVSProxy = [[self alloc] initWithAccount: [CKDSecuritydAccount securitydAccount]
                                                     store: [CKDKVSStore kvsInterface]];
        });
    }
    return sharedKVSProxy;
}

- (id)initWithAccount:(NSObject<CKDAccount>*) account
                store:(NSObject<CKDStore>*) store
{
    if (self = [super init])
    {
        secnotice("event", "%@ start", self);

#if !(TARGET_OS_EMBEDDED)
        // rdar://problem/26247270
        if (geteuid() == 0) {
            secerror("Cannot run CloudKeychainProxy as root");
            return NULL;
        }
#endif
        _unlockedSinceBoot = NO;
        _isLocked = YES;                // until we know for sure
        _ensurePeerRegistration = NO;
        _syncWithPeersPending = NO;


        _account = account;
        _store = store;

        _calloutQueue = dispatch_queue_create("CKDCallout", DISPATCH_QUEUE_SERIAL);
        _ckdkvsproxy_queue = dispatch_get_main_queue();

        _freshnessCompletions = [NSMutableArray<FreshnessResponseBlock> array];

        _syncTimer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, _ckdkvsproxy_queue);
        dispatch_source_set_timer(_syncTimer, DISPATCH_TIME_FOREVER, DISPATCH_TIME_FOREVER, kSyncTimerLeeway);
        dispatch_source_set_event_handler(_syncTimer, ^{
            [self timerFired];
        });
        dispatch_resume(_syncTimer);

        _monitor = [NSMutableDictionary dictionary];

        int notificationToken;
        notify_register_dispatch(kSecServerKeychainChangedNotification, &notificationToken, _ckdkvsproxy_queue,
                                 ^ (int token __unused)
                                 {
                                     secinfo("backoff", "keychain changed, wiping backoff monitor state");
                                     _monitor = [NSMutableDictionary dictionary];
                                 });

        [self importKeyInterests: [SOSPersistentState registeredKeys]];

        // Register for lock state changes
        xpc_set_event_stream_handler(kStreamName, _ckdkvsproxy_queue,
                                     ^(xpc_object_t notification){
                                         [self streamEvent:notification];
                                     });
        _dsid =  @"";

        [self updateUnlockedSinceBoot];
        [self updateIsLocked];
        if (!_isLocked)
            [self keybagDidUnlock];

        [[self store] connectToProxy: self];

        secdebug(XPROXYSCOPE, "%@ done", self);
    }
    return self;
}

- (NSString *)description
{
    return [NSString stringWithFormat:@"<%s%s%s%s%s%s%s%s%s%s%s>",
            _isLocked ? "L" : "U",
            _unlockedSinceBoot ? "B" : "-",
            _seenKVSStoreChange ? "K" : "-",
            _syncTimerScheduled ? "T" : "-",
            _syncWithPeersPending ? "s" : "-",
            _ensurePeerRegistration ? "e" : "-",
            [_pendingKeys count] ? "p" : "-",
            _inCallout ? "C" : "-",
            _shadowSyncWithPeersPending ? "S" : "-",
            _shadowEnsurePeerRegistration ? "E" : "-",
            [_shadowPendingKeys count] ? "P" : "-"];
}

//
// MARK: XPC Function commands
//
- (void) clearStore {
    [self.store removeAllObjects];
}

- (void)synchronizeStore {
    [self.store pushWrites];
}

- (id) objectForKey: (NSString*) key {
    return [self.store objectForKey: key];
}
- (NSDictionary<NSString *, id>*) copyAsDictionary {
    return [self.store copyAsDictionary];
}

//
//
//
- (void)processAllItems
{
    NSDictionary *allItems = [self.store copyAsDictionary];
    if (allItems)
    {
        secnotice("event", "%@ sending: %@", self, [[allItems allKeys] componentsJoinedByString: @" "]);
        [self processKeyChangedEvent:allItems];
    }
    else
        secdebug(XPROXYSCOPE, "%@ No items in KVS", self);
}

- (void)dealloc
{
    secdebug(XPROXYSCOPE, "%@", self);
    [[NSNotificationCenter defaultCenter] removeObserver:self
                                                    name:NSUbiquitousKeyValueStoreDidChangeExternallyNotification
                                                  object:nil];
    
    [[NSNotificationCenter defaultCenter] removeObserver:self
                                                    name:NSUbiquityIdentityDidChangeNotification
                                                  object:nil];
}

// MARK: Penalty measurement and handling
-(dispatch_source_t)setNewTimer:(int)timeout key:(NSString*)key
{
    __block dispatch_source_t timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, _ckdkvsproxy_queue);
    dispatch_source_set_timer(timer, dispatch_time(DISPATCH_TIME_NOW, timeout * NSEC_PER_SEC * seconds_per_minute), DISPATCH_TIME_FOREVER, kSyncTimerLeeway);
    dispatch_source_set_event_handler(timer, ^{
        [self penaltyTimerFired:key];
    });
    dispatch_resume(timer);
    return timer;
}

-(void) increasePenalty:(NSNumber*)currentPenalty key:(NSString*)key keyEntry:(NSMutableDictionary**)keyEntry
{
    secnotice("backoff", "increasing penalty!");
    int newPenalty = 0;
    if([currentPenalty intValue] == max_penalty_timeout){
        newPenalty = max_penalty_timeout;
    }
    else if ([currentPenalty intValue] == 0)
        newPenalty = 1;
    else
        newPenalty = [currentPenalty intValue]*2;
    
    secnotice("backoff", "key %@, waiting %d minutes long to send next messages", key, newPenalty);
    
    NSNumber* penalty_timeout = [[NSNumber alloc]initWithInt:newPenalty];
    dispatch_source_t existingTimer = [*keyEntry valueForKey:kMonitorPenaltyTimer];
    
    if(existingTimer != nil){
        [*keyEntry removeObjectForKey:kMonitorPenaltyTimer];
        dispatch_suspend(existingTimer);
        dispatch_source_set_timer(existingTimer,dispatch_time(DISPATCH_TIME_NOW, newPenalty * NSEC_PER_SEC * seconds_per_minute), DISPATCH_TIME_FOREVER, kSyncTimerLeeway);
        dispatch_resume(existingTimer);
        [*keyEntry setObject:existingTimer forKey:kMonitorPenaltyTimer];
    }
    else{
        dispatch_source_t timer = [self setNewTimer:newPenalty key:key];
        [*keyEntry setObject:timer forKey:kMonitorPenaltyTimer];
    }
    
    [*keyEntry setObject:penalty_timeout forKey:kMonitorPenaltyBoxKey];
    [_monitor setObject:*keyEntry forKey:key];
}

-(void) decreasePenalty:(NSNumber*)currentPenalty key:(NSString*)key keyEntry:(NSMutableDictionary**)keyEntry
{
    int newPenalty = 0;
    secnotice("backoff","decreasing penalty!");
    if([currentPenalty intValue] == 0 || [currentPenalty intValue] == 1)
        newPenalty = 0;
    else
        newPenalty = [currentPenalty intValue]/2;
    
    secnotice("backoff","key %@, waiting %d minutes long to send next messages", key, newPenalty);
    
    NSNumber* penalty_timeout = [[NSNumber alloc]initWithInt:newPenalty];
    
    dispatch_source_t existingTimer = [*keyEntry valueForKey:kMonitorPenaltyTimer];
    if(existingTimer != nil){
        [*keyEntry removeObjectForKey:kMonitorPenaltyTimer];
        dispatch_suspend(existingTimer);
        if(newPenalty != 0){
            dispatch_source_set_timer(existingTimer,dispatch_time(DISPATCH_TIME_NOW, newPenalty * NSEC_PER_SEC * seconds_per_minute), DISPATCH_TIME_FOREVER, kSyncTimerLeeway);
            dispatch_resume(existingTimer);
            [*keyEntry setObject:existingTimer forKey:kMonitorPenaltyTimer];
        }
        else{
            dispatch_resume(existingTimer);
            dispatch_source_cancel(existingTimer);
        }
    }
    else{
        if(newPenalty != 0){
            dispatch_source_t timer = [self setNewTimer:newPenalty key:key];
            [*keyEntry setObject:timer forKey:kMonitorPenaltyTimer];
        }
    }
    
    [*keyEntry setObject:penalty_timeout forKey:kMonitorPenaltyBoxKey];
    [_monitor setObject:*keyEntry forKey:key];
    
}

- (void)penaltyTimerFired:(NSString*)key
{
    secnotice("backoff", "key: %@, !!!!!!!!!!!!!!!!penalty timeout is up!!!!!!!!!!!!", key);

    NSMutableDictionary *keyEntry = [_monitor objectForKey:key];
    NSMutableDictionary *queuedMessages = [keyEntry objectForKey:kMonitorMessageQueue];
    secnotice("backoff","key: %@, queuedMessages: %@", key, queuedMessages);
    if(queuedMessages && [queuedMessages count] != 0){
        secnotice("backoff","key: %@, message queue not empty, writing to KVS!", key);
        [self setObjectsFromDictionary:queuedMessages];
        [keyEntry setObject:[NSMutableDictionary dictionary] forKey:kMonitorMessageQueue];
    }
    
    NSNumber *penalty_timeout = [keyEntry valueForKey:kMonitorPenaltyBoxKey];
    secnotice("backoff", "key: %@, current penalty timeout: %@", key, penalty_timeout);

    NSString* didWriteDuringTimeout = [keyEntry objectForKey:kMonitorDidWriteDuringPenalty];
    if( didWriteDuringTimeout && [didWriteDuringTimeout isEqualToString:@"YES"] )
    {
        //increase timeout since we wrote during out penalty timeout
        [self increasePenalty:penalty_timeout key:key keyEntry:&keyEntry];
    }
    else{
        //decrease timeout since we successfully wrote messages out
        [self decreasePenalty:penalty_timeout key:key keyEntry:&keyEntry];
    }
    
    //resetting the check
    [keyEntry setObject: @"NO" forKey:kMonitorDidWriteDuringPenalty];
    
    //recompute the timetable and number of consecutive writes to KVS
    NSMutableDictionary *timetable = [keyEntry valueForKey:kMonitorTimeTable];
    NSNumber *consecutiveWrites = [keyEntry valueForKey:kMonitorConsecutiveWrites];
    [self recordTimestampForAppropriateInterval:&timetable key:key consecutiveWrites:&consecutiveWrites];
    
    [keyEntry setObject:consecutiveWrites forKey:kMonitorConsecutiveWrites];
    [keyEntry setObject:timetable forKey:kMonitorTimeTable];
    [_monitor setObject:keyEntry forKey:key];
}

-(NSMutableDictionary*)initializeTimeTable:(NSString*)key
{
    NSDate *currentTime = [NSDate date];
    NSMutableDictionary *firstMinute = [NSMutableDictionary dictionaryWithObjectsAndKeys:[currentTime dateByAddingTimeInterval: seconds_per_minute], kMonitorFirstMinute, @"YES", kMonitorWroteInTimeSlice, nil];
    NSMutableDictionary *secondMinute = [NSMutableDictionary dictionaryWithObjectsAndKeys:[currentTime dateByAddingTimeInterval: seconds_per_minute * 2],kMonitorSecondMinute, @"NO", kMonitorWroteInTimeSlice, nil];
    NSMutableDictionary *thirdMinute = [NSMutableDictionary dictionaryWithObjectsAndKeys:[currentTime dateByAddingTimeInterval: seconds_per_minute * 3], kMonitorThirdMinute, @"NO",kMonitorWroteInTimeSlice, nil];
    NSMutableDictionary *fourthMinute = [NSMutableDictionary dictionaryWithObjectsAndKeys:[currentTime dateByAddingTimeInterval: seconds_per_minute * 4],kMonitorFourthMinute, @"NO", kMonitorWroteInTimeSlice, nil];
    NSMutableDictionary *fifthMinute = [NSMutableDictionary dictionaryWithObjectsAndKeys:[currentTime dateByAddingTimeInterval: seconds_per_minute * 5], kMonitorFifthMinute, @"NO", kMonitorWroteInTimeSlice, nil];
    
    NSMutableDictionary *timeTable = [NSMutableDictionary dictionaryWithObjectsAndKeys: firstMinute, kMonitorFirstMinute,
                                      secondMinute, kMonitorSecondMinute,
                                      thirdMinute, kMonitorThirdMinute,
                                      fourthMinute, kMonitorFourthMinute,
                                      fifthMinute, kMonitorFifthMinute, nil];
    return timeTable;
}

- (void)initializeKeyEntry:(NSString*)key
{
    NSMutableDictionary *timeTable = [self initializeTimeTable:key];
    NSDate *currentTime = [NSDate date];
    
    NSMutableDictionary *keyEntry = [NSMutableDictionary dictionaryWithObjectsAndKeys: key, kMonitorMessageKey, @0, kMonitorConsecutiveWrites, currentTime, kMonitorLastWriteTimestamp, @0, kMonitorPenaltyBoxKey, timeTable, kMonitorTimeTable,[NSMutableDictionary dictionary], kMonitorMessageQueue, nil];
    
    [_monitor setObject:keyEntry forKey:key];
    
}

- (void)recordTimestampForAppropriateInterval:(NSMutableDictionary**)timeTable key:(NSString*)key consecutiveWrites:(NSNumber**)consecutiveWrites
{
    NSDate *currentTime = [NSDate date];
    __block int cWrites = [*consecutiveWrites intValue];
    __block BOOL foundTimeSlot = NO;
    __block NSMutableDictionary *previousTable = nil;
    NSArray *sorted = [[*timeTable allKeys] sortedArrayUsingSelector:@selector(compare:)];
    [sorted enumerateObjectsUsingBlock:^(id sortedKey, NSUInteger idx, BOOL *stop)
     {
         if(foundTimeSlot == YES)
             return;
         [*timeTable enumerateKeysAndObjectsUsingBlock: ^(id minute, id obj, BOOL *stop2)
          {
              if(foundTimeSlot == YES)
                  return;
              if([sortedKey isEqualToString:minute]){
                  NSMutableDictionary *minutesTable = (NSMutableDictionary*)obj;
                  NSString *minuteKey = (NSString*)minute;
                  NSDate *date = [minutesTable valueForKey:minuteKey];
                  if([date compare:currentTime] == NSOrderedDescending){
                      foundTimeSlot = YES;
                      NSString* written = [minutesTable valueForKey:kMonitorWroteInTimeSlice];
                      if([written isEqualToString:@"NO"]){
                          [minutesTable setObject:@"YES" forKey:kMonitorWroteInTimeSlice];
                          if(previousTable != nil){
                              written = [previousTable valueForKey:kMonitorWroteInTimeSlice];
                              if([written isEqualToString:@"YES"]){
                                  cWrites++;
                              }
                              else if ([written isEqualToString:@"NO"]){
                                  cWrites = 0;
                              }
                          }
                      }
                      return;
                  }
                  previousTable = minutesTable;
              }
          }];
     }];
    
    if(foundTimeSlot == NO){
        //reset the time table
        secnotice("backoff","didn't find a time slot, resetting the table");
        NSMutableDictionary *lastTable = [*timeTable valueForKey:kMonitorFifthMinute];
        NSDate *lastDate = [lastTable valueForKey:kMonitorFifthMinute];
        
        if((double)[currentTime timeIntervalSinceDate: lastDate] >= seconds_per_minute){
            *consecutiveWrites = [[NSNumber alloc]initWithInt:0];
        }
        else{
            NSString* written = [lastTable valueForKey:kMonitorWroteInTimeSlice];
            if([written isEqualToString:@"YES"]){
                cWrites++;
                *consecutiveWrites = [[NSNumber alloc]initWithInt:cWrites];
            }
            else{
                *consecutiveWrites = [[NSNumber alloc]initWithInt:0];
            }
        }
        
        *timeTable  = [self initializeTimeTable:key];
        return;
    }
    *consecutiveWrites = [[NSNumber alloc]initWithInt:cWrites];
}
- (void)recordWriteToKVS:(NSDictionary *)values
{
    if([_monitor count] == 0){
        [values enumerateKeysAndObjectsUsingBlock: ^(id key, id obj, BOOL *stop)
         {
             [self initializeKeyEntry: key];
         }];
    }
    else{
        [values enumerateKeysAndObjectsUsingBlock: ^(id key, id obj, BOOL *stop)
         {
             NSMutableDictionary *keyEntry = [_monitor objectForKey:key];
             if(keyEntry == nil){
                 [self initializeKeyEntry: key];
             }
             else{
                 NSNumber *penalty_timeout = [keyEntry objectForKey:kMonitorPenaltyBoxKey];
                 NSDate *lastWriteTimestamp = [keyEntry objectForKey:kMonitorLastWriteTimestamp];
                 NSMutableDictionary *timeTable = [keyEntry objectForKey: kMonitorTimeTable];
                 NSNumber *existingWrites = [keyEntry objectForKey: kMonitorConsecutiveWrites];
                 NSDate *currentTime = [NSDate date];
                 
                 [self recordTimestampForAppropriateInterval:&timeTable key:key consecutiveWrites:&existingWrites];
                 
                 int consecutiveWrites = [existingWrites intValue];
                 secnotice("backoff","consecutive writes: %d", consecutiveWrites);
                 [keyEntry setObject:existingWrites forKey:kMonitorConsecutiveWrites];
                 [keyEntry setObject:timeTable forKey:kMonitorTimeTable];
                 [keyEntry setObject:currentTime forKey:kMonitorLastWriteTimestamp];
                 [_monitor setObject:keyEntry forKey:key];
                 
                 if([penalty_timeout intValue] != 0 || ((double)[currentTime timeIntervalSinceDate: lastWriteTimestamp] <= 60 && consecutiveWrites >= 5)){
                     if([penalty_timeout intValue] != 0 && consecutiveWrites == 5){
                         secnotice("backoff","written for 5 consecutive minutes, time to start throttling");
                         [self increasePenalty:penalty_timeout key:key keyEntry:&keyEntry];
                     }
                     else
                         secnotice("backoff","monitor: keys have been written for 5 or more minutes, recording we wrote during timeout");
                   
                     //record we wrote during a timeout
                     [keyEntry setObject: @"YES" forKey:kMonitorDidWriteDuringPenalty];
                 }
                 //keep writing freely but record it
                 else if((double)[currentTime timeIntervalSinceDate: lastWriteTimestamp] <= 60 && consecutiveWrites < 5){
                     secnotice("backoff","monitor: still writing freely");
                 }
             }
         }];
    }
}

- (NSDictionary*)recordHaltedValuesAndReturnValuesToSafelyWrite:(NSDictionary *)values
{
    NSMutableDictionary *SafeMessages = [NSMutableDictionary dictionary];
    [values enumerateKeysAndObjectsUsingBlock: ^(id key, id obj, BOOL *stop)
     {
         NSMutableDictionary *keyEntry = [_monitor objectForKey:key];
         NSNumber *penalty = [keyEntry objectForKey:kMonitorPenaltyBoxKey];
         if([penalty intValue] != 0){
             NSMutableDictionary* existingQueue = [keyEntry valueForKey:kMonitorMessageQueue];
             
             [existingQueue setObject:obj forKey:key];
             
             [keyEntry setObject:existingQueue forKey:kMonitorMessageQueue];
             [_monitor setObject:keyEntry forKey:key];
         }
         else{
             [SafeMessages setObject:obj forKey:key];
         }
     }];
    return SafeMessages;
}

// MARK: Object setting


- (void)setStoreObjectsFromDictionary:(NSDictionary *)values
{
    if (values == nil) {
        secdebug(XPROXYSCOPE, "%@ NULL? values: %@", self, values);
        return;
    }

    NSMutableDictionary<NSString*, NSObject*> *mutableValues = [values mutableCopy];
    NSString* newDSID = asNSString([mutableValues extractObjectForKey:(__bridge NSString*) kSOSKVSOfficialDSIDKey]);
    if (newDSID) {
        _dsid = newDSID;
    }

    NSString* requiredDSID = asNSString([mutableValues extractObjectForKey:(__bridge NSString*) kSOSKVSRequiredKey]);
    if (requiredDSID) {
        if (_dsid == nil || [_dsid isEqualToString: @""]) {
            secdebug("dsid", "CloudKeychainProxy setting dsid to :%@ from securityd", requiredDSID);
            _dsid = requiredDSID;
        } else if (![_dsid isEqual: requiredDSID]) {
            secerror("Account DSIDs do not match, cloud keychain proxy: %@, securityd: %@", _dsid, requiredDSID);
            secerror("Not going to write these: %@ into KVS!", values);
            return;
        } else {
            secnoticeq("dsid", "DSIDs match, writing");
        }
    }

    secnoticeq("keytrace", "%@ sending: %@", self, [[mutableValues allKeys] componentsJoinedByString: @" "]);
    [mutableValues enumerateKeysAndObjectsUsingBlock: ^(id key, id obj, BOOL *stop)
     {
         if (obj == NULL || obj == [NSNull null]) {
             [self.store removeObjectForKey:key];
         } else {
             if ([key hasPrefix:@"ak|"]) {  // TODO: somewhat of a hack
                 id oldObj = [self.store objectForKey:key];
                 if ([oldObj isEqual: obj]) {
                     // Fix KVS repeated message undelivery by sending a NULL first (deafness)
                     secnoticeq("keytrace", "forcing resend of key write: %@", key);
                     [self.store removeObjectForKey:key];
                 }
             }
             [self.store setObject:obj forKey:key];
         }
     }];

    [self.store pushWrites];
}

- (void)setObjectsFromDictionary:(NSDictionary<NSString*, NSObject*> *)values
{
    [[UbiqitousKVSProxy sharedKVSProxy] recordWriteToKVS: values];
    NSDictionary *safeValues = [[UbiqitousKVSProxy sharedKVSProxy] recordHaltedValuesAndReturnValuesToSafelyWrite: values];
    if([safeValues count] !=0){
        [[UbiqitousKVSProxy sharedKVSProxy] setStoreObjectsFromDictionary:safeValues];
    }
}

- (void)waitForSynchronization:(void (^)(NSDictionary<NSString*, NSObject*> *results, NSError *err))handler
{
    secnoticeq("fresh", "%s Requesting WFS", kWAIT2MINID);

    [_freshnessCompletions addObject: ^(bool success, NSError *error){
        secnoticeq("fresh", "%s WFS Done", kWAIT2MINID);
        handler(nil, error);
    }];

    if ([self.freshnessCompletions count] == 1) {
        // We can't talk to synchronize on the _ckdkvsproxy_queue or we deadlock,
        // bounce to a global concurrent queue
        dispatch_after(_nextFreshnessTime, dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
            NSError *error = nil;
            bool success = [self.store pullUpdates:&error];

            dispatch_async(_ckdkvsproxy_queue, ^{
                [self waitForSyncDone: success error: error];
            });
        });
    }
}

- (void) waitForSyncDone: (bool) success error: (NSError*) error{
    if (success) {
        const uint64_t delayBeforeCallingAgainInSeconds = 5ull * NSEC_PER_SEC;
        _nextFreshnessTime  = dispatch_time(DISPATCH_TIME_NOW, delayBeforeCallingAgainInSeconds);
    }

    secnoticeq("fresh", "%s Completing WFS", kWAIT2MINID);
    [_freshnessCompletions enumerateObjectsUsingBlock:^(FreshnessResponseBlock _Nonnull block,
                                                        NSUInteger idx,
                                                        BOOL * _Nonnull stop) {
        block(success, error);
    }];
    [_freshnessCompletions removeAllObjects];

}

//
// MARK: ----- KVS key lists -----
//


- (NSDictionary*) exportKeyInterests
{
    return @{ kKeyAlwaysKeys:[_alwaysKeys allObjects],
              kKeyFirstUnlockKeys:[_firstUnlockKeys allObjects],
              kKeyUnlockedKeys:[_unlockedKeys allObjects],
              kMonitorState:_monitor,
              kKeyPendingKeys:[_pendingKeys allObjects],
              kKeySyncWithPeersPending:[NSNumber numberWithBool:_syncWithPeersPending],
              kKeyEnsurePeerRegistration:[NSNumber numberWithBool:_ensurePeerRegistration],
              kKeyDSID:_dsid
              };
}

- (void) importKeyInterests: (NSDictionary*) interests
{
    _alwaysKeys = [NSMutableSet setWithArray: interests[kKeyAlwaysKeys]];
    _firstUnlockKeys = [NSMutableSet setWithArray: interests[kKeyFirstUnlockKeys]];
    _unlockedKeys = [NSMutableSet setWithArray: interests[kKeyUnlockedKeys]];

    _pendingKeys = [NSMutableSet setWithArray: interests[kKeyPendingKeys]];
    _syncWithPeersPending = [interests[kKeySyncWithPeersPending] boolValue];
    _ensurePeerRegistration = [interests[kKeyEnsurePeerRegistration] boolValue];
    _dsid = interests[kKeyDSID];
    _monitor = interests[kMonitorState];
    if(_monitor == nil)
        _monitor = [NSMutableDictionary dictionary];
    
}

- (NSMutableSet *)copyAllKeyInterests
{
    NSMutableSet *allKeys = [NSMutableSet setWithSet: _alwaysKeys];
    [allKeys unionSet: _firstUnlockKeys];
    [allKeys unionSet: _unlockedKeys];
    return allKeys;
}

-(void)registerAtTimeKeys:(NSDictionary*)keyparms
{
    if (keyparms == nil)
        return;

    NSArray *alwaysArray = [keyparms valueForKey: kKeyAlwaysKeys];
    NSArray *firstUnlockedKeysArray = [keyparms valueForKey: kKeyFirstUnlockKeys];
    NSArray *whenUnlockedKeysArray = [keyparms valueForKey: kKeyUnlockedKeys];
    
    if(alwaysArray)
        [_alwaysKeys unionSet: [NSMutableSet setWithArray: alwaysArray]];
    if(firstUnlockedKeysArray)
        [_firstUnlockKeys unionSet: [NSMutableSet setWithArray: firstUnlockedKeysArray]];
    if(whenUnlockedKeysArray)
        [_unlockedKeys unionSet: [NSMutableSet setWithArray: whenUnlockedKeysArray]];
}


- (void)registerKeys: (NSDictionary*)keys
{
    secdebug(XPROXYSCOPE, "registerKeys: keys: %@", keys);
    
    NSMutableSet *allOldKeys = [self copyAllKeyInterests];

    NSDictionary *keyparms = [keys valueForKey: [NSString stringWithUTF8String: kMessageKeyParameter]];
    NSDictionary *circles = [keys valueForKey: [NSString stringWithUTF8String: kMessageCircle]];
    NSDictionary *messages = [keys valueForKey: [NSString stringWithUTF8String: kMessageMessage]];
    
    _alwaysKeys = [NSMutableSet set];
    _firstUnlockKeys = [NSMutableSet set];
    _unlockedKeys = [NSMutableSet set];

    [self registerAtTimeKeys: keyparms];
    [self registerAtTimeKeys: circles];
    [self registerAtTimeKeys: messages];

    NSMutableSet *allNewKeys = [self copyAllKeyInterests];
    
    // Make sure keys we no longer care about are not pending
    [_pendingKeys intersectSet:allNewKeys];
    if (_shadowPendingKeys) {
        [_shadowPendingKeys intersectSet:allNewKeys];
    }

    // All new keys only is new keys (remove old keys)
    [allNewKeys minusSet:allOldKeys];

    // Mark new keys pending, they're new!
    NSMutableSet *newKeysForCurrentLockState = [self pendKeysAndGetNewlyPended:allNewKeys];

    [self persistState]; // Before we might call out, save our state so we recover if we crash
    
    [self intersectWithCurrentLockState: newKeysForCurrentLockState];
    // TODO: Don't processPendingKeysForCurrentLockState if none of the new keys have values.
    if ([newKeysForCurrentLockState count] != 0) {
        [self processPendingKeysForCurrentLockState];
    }
}

// MARK: ----- Event Handling -----

- (void)streamEvent:(xpc_object_t)notification
{
#if (!TARGET_IPHONE_SIMULATOR)
    const char *notificationName = xpc_dictionary_get_string(notification, "Notification");
    if (!notificationName) {
    } else if (strcmp(notificationName, kUserKeybagStateChangeNotification)==0) {
        return [self keybagStateChange];
    } else if (strcmp(notificationName, kCloudKeychainStorechangeChangeNotification)==0) {
        return [self kvsStoreChange];
    } else if (strcmp(notificationName, kNotifyTokenForceUpdate)==0) {
        // DEBUG -- Possibly remove in future
        return [self processAllItems];
    }
    const char *eventName = xpc_dictionary_get_string(notification, "XPCEventName");
    char *desc = xpc_copy_description(notification);
    secnotice("event", "%@ event: %s name: %s desc: %s", self, eventName, notificationName, desc);
    if (desc)
        free((void *)desc);
#endif
}

- (void)storeKeysChanged: (NSSet<NSString*>*) changedKeys initial: (bool) initial
{
    // Mark that our store is talking to us, so we don't have to make up for missing anything previous.
    _seenKVSStoreChange = YES;

    // Unmark them as pending as they have just changed and we'll process them.
    [_pendingKeys minusSet:changedKeys];

    // Only send values that we're currently interested in.
    NSSet *keysOfInterestThatChanged = [self pendKeysAndGetPendingForCurrentLockState:changedKeys];
    NSMutableDictionary *changedValues = [self copyValues:keysOfInterestThatChanged];
    if (initial)
        changedValues[(__bridge NSString*)kSOSKVSInitialSyncKey] =  @"true";

    secnotice("event", "%@ keysChangedInCloud: %@ keysOfInterest: %@ initial: %@",
              self,
              [[changedKeys allObjects] componentsJoinedByString: @" "],
              [[changedValues allKeys] componentsJoinedByString: @" "],
              initial ? @"YES" : @"NO");

    if ([changedValues count])
        [self processKeyChangedEvent:changedValues];
}

- (void)storeAccountChanged
{
    secnotice("event", "%@", self);

    NSDictionary *changedValues = nil;
    if(_dsid)
        changedValues = @{ (__bridge NSString*)kSOSKVSAccountChangedKey: _dsid };
    else
        changedValues = @{ (__bridge NSString*)kSOSKVSAccountChangedKey: @"true" };

    [self processKeyChangedEvent:changedValues];
}

- (void) doAfterFlush: (dispatch_block_t) block
{
    //Flush any pending communication to Securityd.
    if(!_inCallout)
        dispatch_async(_calloutQueue, block);
    else
        _shadowFlushBlock = block;
}

- (void) calloutWith: (void(^)(NSSet *pending, bool syncWithPeersPending, bool ensurePeerRegistration,
                               dispatch_queue_t queue, void(^done)(NSSet *handledKeys, bool handledSyncWithPeers, bool handledEnsurePeerRegistration, NSError* error))) callout
{
    // In CKDKVSProxy's serial queue

    // dispatch_get_global_queue - well-known global concurrent queue
    // dispatch_get_main_queue   - default queue that is bound to the main thread
    xpc_transaction_begin();
    dispatch_async(_calloutQueue, ^{
        __block NSSet *myPending;
        __block bool mySyncWithPeersPending;
        __block bool myEnsurePeerRegistration;
        __block bool wasLocked;
        dispatch_sync(_ckdkvsproxy_queue, ^{
            myPending = [_pendingKeys copy];
            mySyncWithPeersPending = _syncWithPeersPending;
            myEnsurePeerRegistration = _ensurePeerRegistration;
            wasLocked = _isLocked;

            _inCallout = YES;

            _shadowPendingKeys = [NSMutableSet set];
            _shadowSyncWithPeersPending = NO;
        });

        callout(myPending, mySyncWithPeersPending, myEnsurePeerRegistration, _ckdkvsproxy_queue, ^(NSSet *handledKeys, bool handledSyncWithPeers, bool handledEnsurePeerRegistration, NSError* failure) {
            secdebug("event", "%@ %s%s before callout handled: %s%s", self, mySyncWithPeersPending ? "S" : "s", myEnsurePeerRegistration ? "E" : "e", handledSyncWithPeers ? "S" : "s", handledEnsurePeerRegistration ? "E" : "e");
            
            // In CKDKVSProxy's serial queue
            _inCallout = NO;
            
            // Update ensurePeerRegistration
            _ensurePeerRegistration = ((myEnsurePeerRegistration && !handledEnsurePeerRegistration) || _shadowEnsurePeerRegistration);
            
            _shadowEnsurePeerRegistration = NO;
            
            if(_ensurePeerRegistration && !_isLocked)
                [self doEnsurePeerRegistration];
            
            // Update SyncWithPeers stuff.
            _syncWithPeersPending = ((mySyncWithPeersPending && (!handledSyncWithPeers)) || _shadowSyncWithPeersPending);
            
            _shadowSyncWithPeersPending = NO;
            if (handledSyncWithPeers)
                _lastSyncTime = dispatch_time(DISPATCH_TIME_NOW, 0);
            
            // Update pendingKeys and handle them
            [_pendingKeys removeObject: [NSNull null]]; // Don't let NULL hang around

            [_pendingKeys minusSet: handledKeys];
            bool hadShadowPendingKeys = [_shadowPendingKeys count];
            // Move away shadownPendingKeys first, because pendKeysAndGetPendingForCurrentLockState
            // will look at them. See rdar://problem/20733166.
            NSSet *oldShadowPendingKeys = _shadowPendingKeys;
            _shadowPendingKeys = nil;

            NSSet *filteredKeys = [self pendKeysAndGetPendingForCurrentLockState:oldShadowPendingKeys];

            secnoticeq("keytrace", "%@ account handled: %@ pending: %@", self,
                       [[handledKeys allObjects] componentsJoinedByString: @" "],
                       [[filteredKeys allObjects] componentsJoinedByString: @" "]);

            // Write state to disk
            [self persistState];
            
            // Handle shadow pended stuff
            if (_syncWithPeersPending && !_isLocked)
                [self scheduleSyncRequestTimer];
            /* We don't want to call processKeyChangedEvent if we failed to
             handle pending keys and the device didn't unlock nor receive
             any kvs changes while we were in our callout.
             Doing so will lead to securityd and CloudKeychainProxy
             talking to each other forever in a tight loop if securityd
             repeatedly returns an error processing the same message.
             Instead we leave any old pending keys until the next event. */

            if (hadShadowPendingKeys || (!_isLocked && wasLocked)){
                [self processKeyChangedEvent:[self copyValues:filteredKeys]];
                if(_shadowFlushBlock != NULL)
                    secerror("Flush block is not null and sending new keys");
            }
            if(_shadowFlushBlock != NULL){
                dispatch_async(_calloutQueue, _shadowFlushBlock);
                _shadowFlushBlock = NULL;
            }

            if (failure) {
                [self updateIsLocked];
            }
            
            xpc_transaction_end();
        });
    });
}

- (void) sendKeysCallout: (NSSet *(^)(NSSet* pending, NSError** error)) handleKeys {
    [self calloutWith: ^(NSSet *pending, bool syncWithPeersPending, bool ensurePeerRegistration, dispatch_queue_t queue, void(^done)(NSSet *, bool, bool, NSError*)) {
        NSError* error = NULL;

        secnotice("CloudKeychainProxy", "send keys: %@", pending);
        NSSet * handled = handleKeys(pending, &error);

        dispatch_async(queue, ^{
            if (!handled) {
                secerror("%@ ensurePeerRegistration failed: %@", self, error);
            }

            done(handled, NO, NO, error);
        });
    }];
}

- (void) doEnsurePeerRegistration
{
    NSObject<CKDAccount>* accountDelegate = [self account];
    [self calloutWith:^(NSSet *pending, bool syncWithPeersPending, bool ensurePeerRegistration, dispatch_queue_t queue, void(^done)(NSSet *, bool, bool, NSError*)) {
        NSError* error = nil;
        bool handledEnsurePeerRegistration = [accountDelegate ensurePeerRegistration:&error];
        secnotice("EnsurePeerRegistration", "%@ ensurePeerRegistration called, %@ (%@)", self, handledEnsurePeerRegistration ? @"success" : @"failure", error);
        dispatch_async(queue, ^{
            done(nil, NO, handledEnsurePeerRegistration, error);
        });
    }];
}

- (void) doSyncWithAllPeers
{
    NSObject<CKDAccount>* accountDelegate = [self account];
    [self calloutWith:^(NSSet *pending, bool syncWithPeersPending, bool ensurePeerRegistration, dispatch_queue_t queue, void(^done)(NSSet *, bool, bool, NSError*)) {
        NSError* error = NULL;
        SyncWithAllPeersReason reason = [accountDelegate syncWithAllPeers: &error];
        dispatch_async(queue, ^{
            bool handledSyncWithPeers = NO;
            if (reason == kSyncWithAllPeersSuccess) {
                handledSyncWithPeers = YES;
                secnotice("event", "%@ syncWithAllPeers succeeded", self);
            } else if (reason == kSyncWithAllPeersLocked) {
                secnotice("event", "%@ syncWithAllPeers attempted while locked - waiting for unlock", self);
                handledSyncWithPeers = NO;
                [self updateIsLocked];
            } else if (reason == kSyncWithAllPeersOtherFail) {
                // Pretend we handled syncWithPeers, by pushing out the _lastSyncTime
                // This will cause us to wait for kMinSyncInterval seconds before
                // retrying, so we don't spam securityd if sync is failing
                secerror("%@ syncWithAllPeers %@, rescheduling timer", self, error);
                _lastSyncTime = dispatch_time(DISPATCH_TIME_NOW, 0);
            } else {
                secerror("%@ syncWithAllPeers %@, unknown reason: %d", self, error, reason);
            }
            
            done(nil, handledSyncWithPeers, false, error);
        });
    }];
}

- (void)timerFired
{
    secnotice("event", "%@ syncWithPeersPending: %d inCallout: %d isLocked: %d", self, _syncWithPeersPending, _inCallout, _isLocked);
    _syncTimerScheduled = NO;
    if(_ensurePeerRegistration){
        [self doEnsurePeerRegistration];
    }
    if (_syncWithPeersPending && !_inCallout && !_isLocked){
        [self doSyncWithAllPeers];
    }
}

- (dispatch_time_t) nextSyncTime
{
    dispatch_time_t nextSync = dispatch_time(DISPATCH_TIME_NOW, kMinSyncDelay);
    
    // Don't sync again unless we waited at least kMinSyncInterval
    if (_lastSyncTime) {
        dispatch_time_t soonest = dispatch_time(_lastSyncTime, kMinSyncInterval);
        if (nextSync < soonest || _deadline < soonest) {
            secdebug("timer", "%@ backing off", self);
            return soonest;
        }
    }
    
    // Don't delay more than kMaxSyncDelay after the first request.
    if (nextSync > _deadline) {
        secdebug("timer", "%@ hit deadline", self);
        return _deadline;
    }
    
    // Bump the timer by kMinSyncDelay
    if (_syncTimerScheduled)
        secdebug("timer", "%@ bumped timer", self);
    else
        secdebug("timer", "%@ scheduled timer", self);
    
    return nextSync;
}

- (void)scheduleSyncRequestTimer
{
    dispatch_source_set_timer(_syncTimer, [self nextSyncTime], DISPATCH_TIME_FOREVER, kSyncTimerLeeway);
    _syncTimerScheduled = YES;
}

- (void)requestSyncWithAllPeers // secd calling SOSCCSyncWithAllPeers invokes this
{
#if !defined(NDEBUG)
    NSString *desc = [self description];
#endif
        
    if (!_syncWithPeersPending || (_inCallout && !_shadowSyncWithPeersPending))
        _deadline = dispatch_time(DISPATCH_TIME_NOW, kMaxSyncDelay);
    
    if (!_syncWithPeersPending) {
        _syncWithPeersPending = YES;
        [self persistState];
    }
    
    if (_inCallout)
        _shadowSyncWithPeersPending = YES;
    else if (!_isLocked)
        [self scheduleSyncRequestTimer];
    
    secdebug("event", "%@ %@", desc, self);
}

- (void)requestEnsurePeerRegistration // secd calling SOSCCSyncWithAllPeers invokes this
{
#if !defined(NDEBUG)
    NSString *desc = [self description];
#endif
    
    if (_inCallout) {
        _shadowEnsurePeerRegistration = YES;
    } else {
        _ensurePeerRegistration = YES;
        if (!_isLocked){
            [self doEnsurePeerRegistration];
        }
        [self persistState];
    }
    
    secdebug("event", "%@ %@", desc, self);
}


- (BOOL) updateUnlockedSinceBoot
{
    CFErrorRef aksError = NULL;
    if (!SecAKSGetHasBeenUnlocked(&_unlockedSinceBoot, &aksError)) {
        secerror("%@ Got error from SecAKSGetHasBeenUnlocked: %@", self, aksError);
        CFReleaseSafe(aksError);
        return NO;
    }
    return YES;
}

- (BOOL) updateIsLocked
{
    CFErrorRef aksError = NULL;
    if (!SecAKSGetIsLocked(&_isLocked, &aksError)) {
        _isLocked = YES;
        secerror("%@ Got error querying lock state: %@", self, aksError);
        CFReleaseSafe(aksError);
        return NO;
    }
    if (!_isLocked)
        _unlockedSinceBoot = YES;
    return YES;
}

- (void) keybagStateChange
{
    os_activity_initiate("keybagStateChanged", OS_ACTIVITY_FLAG_DEFAULT, ^{
        BOOL wasLocked = _isLocked;
        if ([self updateIsLocked]) {
            if (wasLocked == _isLocked)
                secdebug("event", "%@ still %s ignoring", self, _isLocked ? "locked" : "unlocked");
            else if (_isLocked)
                [self keybagDidLock];
            else
                [self keybagDidUnlock];
        }
    });
}

- (void) keybagDidLock
{
    secnotice("event", "%@", self);
}

- (void) keybagDidUnlock
{
    secnotice("event", "%@", self);
    if (_ensurePeerRegistration) {
        [self doEnsurePeerRegistration];
    }
    
    // First send changed keys to securityd so it can proccess updates
    [self processPendingKeysForCurrentLockState];
    
    // Then, tickle securityd to perform a sync if needed.
    if (_syncWithPeersPending && !_syncTimerScheduled) {
        [self doSyncWithAllPeers];
    }
}

- (void) kvsStoreChange {
    os_activity_initiate("kvsStoreChange", OS_ACTIVITY_FLAG_DEFAULT, ^{
        if (!_seenKVSStoreChange) {
            secnotice("event", "%@ received darwin notification before first NSNotification", self);
            // TODO This might not be needed if we always get the NSNotification
            // deleived even if we were launched due to a kvsStoreChange
            // Send all keys for current lock state to securityd so it can proccess them
            [self pendKeysAndGetNewlyPended: [self copyAllKeyInterests]];
            [self processPendingKeysForCurrentLockState];
        } else {
            secdebug("event", "%@ ignored, waiting for NSNotification", self);
        }
    });
}

//
// MARK: ----- Key Filtering -----
//

- (NSSet*) keysForCurrentLockState
{
    secdebug("filtering", "%@ Filtering: unlockedSinceBoot: %d\n unlocked: %d\n, keysOfInterest: <%@>", self, (int) _unlockedSinceBoot, (int) !_isLocked, [SOSPersistentState dictionaryDescription: [self exportKeyInterests]]);

    NSMutableSet *currentStateKeys = [NSMutableSet setWithSet: _alwaysKeys];
    if (_unlockedSinceBoot)
        [currentStateKeys unionSet: _firstUnlockKeys];
    
    if (!_isLocked)
        [currentStateKeys unionSet: _unlockedKeys];
    
    return currentStateKeys;
}


- (NSMutableSet*) pendKeysAndGetNewlyPended: (NSSet*) keysToPend
{
    NSMutableSet *filteredKeysToPend = [self copyAllKeyInterests];
    [filteredKeysToPend intersectSet: keysToPend];
    
    NSMutableSet *newlyPendedKeys = [filteredKeysToPend mutableCopy];
    [newlyPendedKeys minusSet: _pendingKeys];
    if (_shadowPendingKeys) {
        [newlyPendedKeys minusSet: _shadowPendingKeys];
    }
    
    if (_shadowPendingKeys) {
        [_shadowPendingKeys unionSet:filteredKeysToPend];
    }
    else{
        [_pendingKeys unionSet:filteredKeysToPend];
    }
    
    return newlyPendedKeys;
}

- (void) intersectWithCurrentLockState: (NSMutableSet*) set
{
    [set intersectSet: [self keysForCurrentLockState]];
}

- (NSMutableSet*) pendingKeysForCurrentLockState
{
    NSMutableSet * result = [_pendingKeys mutableCopy];
    [self intersectWithCurrentLockState:result];
    return result;
}

- (NSMutableSet*) pendKeysAndGetPendingForCurrentLockState: (NSSet*) startingSet
{
    [self pendKeysAndGetNewlyPended: startingSet];
    
    return [self pendingKeysForCurrentLockState];
}

- (NSMutableDictionary *)copyValues:(NSSet*)keysOfInterest
{
    // Grab values from store.
    NSObject<CKDStore> *store = [self store];
    NSMutableDictionary *changedValues = [NSMutableDictionary dictionaryWithCapacity:0];
    [keysOfInterest enumerateObjectsUsingBlock:^(id obj, BOOL *stop)
     {
         NSString* key = (NSString*) obj;
         id objval = [store objectForKey:key];
         if (!objval) objval = [NSNull null];
         
         [changedValues setObject:objval forKey:key];
         secdebug(XPROXYSCOPE, "%@ storeChanged updated value for %@", self, key);
     }];
    return changedValues;
}

/*
 During RegisterKeys, separate keys-of-interest into three disjoint sets:
 - keys that we always want to be notified about; this means we can get the
 value at any time
 - keys that require the device to have been unlocked at least once
 - keys that require the device to be unlocked now
 
 Typically, the sets of keys will be:
 
 - Dk: alwaysKeys
 - Ck: firstUnlock
 - Ak: unlocked
 
 The caller is responsible for making sure that the keys in e.g. alwaysKeys are
 values that can be handled at any time (that is, not when unlocked)
 
 Each time we get a notification from ubiquity that keys have changed, we need to
 see if anything of interest changed. If we don't care, then done.
 
 For each key-of-interest that changed, we either notify the client that things
 changed, or add it to a pendingNotifications list. If the notification to the
 client fails, also add it to the pendingNotifications list. This pending list
 should be written to persistent storage and consulted any time we either get an
 item changed notification, or get a stream event signalling a change in lock state.
 
 We can notify the client either through XPC if a connection is set up, or call a
 routine in securityd to launch it.
 
 */

- (void)processKeyChangedEvent:(NSDictionary *)changedValues
{
    NSMutableDictionary* filtered = [NSMutableDictionary dictionary];

    secnotice("processKeyChangedEvent", "changedValues:%@", changedValues);
    NSMutableArray* nullKeys = [NSMutableArray array];
    // Remove nulls because we don't want them in securityd.
    [changedValues enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) {
        if (obj == [NSNull null]){
            [nullKeys addObject:key];
        }else{
            filtered[key] = obj;
        }
    }];
    if ([nullKeys count])
        [_pendingKeys minusSet: [NSSet setWithArray: nullKeys]];
    
    if([filtered count] != 0 ) {
        [self sendKeysCallout:^NSSet *(NSSet *pending, NSError** error) {
            secnotice("processing keys", "pending:%@", pending);
            NSError *updateError = nil;
            return [[self account] keysChanged: filtered error: &updateError];
        }];
    } else {
        secnoticeq("keytrace", "%@ null: %@ pending: %@", self,
                  [nullKeys componentsJoinedByString: @" "],
                  [[_pendingKeys allObjects] componentsJoinedByString: @" "]);
    }
}

- (void) processPendingKeysForCurrentLockState
{
    [self processKeyChangedEvent: [self copyValues: [self pendingKeysForCurrentLockState]]];
}

@end


