Add SignalAccount class.

// FREEBIE

Signal/src/ViewControllers/SignalAccount.h

@@ -15,12 +15,13 @@ NS_ASSUME_NONNULL_BEGIN
 //
 // New instances of SignalAccount for active accounts are
 // created every time we do a contacts intersection (e.g.
-// in response to a
+// in response to a change to the device contacts).
 @interface SignalAccount : NSObject
 
-@property (nonatomic) SignalRecipient *signalRecipient;
-
 // An E164 value identifying the signal account.
+//
+// This is the key property of this class and it
+// will always be non-null.
 @property (nonatomic, readonly) NSString *recipientId;
 
 // This property is optional and will not be set for
@@ -33,6 +34,19 @@ NS_ASSUME_NONNULL_BEGIN
 // this is a label for the account.
 @property (nonatomic) NSString *multipleAccountLabel;
 
+- (instancetype)init NS_UNAVAILABLE;
+
+- (instancetype)initWithSignalRecipient:(SignalRecipient *)signalRecipient;
+
+- (instancetype)initWithRecipientId:(NSString *)recipientId;
+
+// In most cases this should be non-null. This should only
+// be non-null in the case where the SignalRecipient was
+// deleted before this property was accessed.
+//
+// NOTE: This may create a database transaction.
+- (nullable SignalRecipient *)signalRecipient;
+
 @end
 
 NS_ASSUME_NONNULL_END

Signal/src/ViewControllers/SignalAccount.m

@@ -4,16 +4,57 @@
 
 #import "SignalAccount.h"
 #import <SignalServiceKit/SignalRecipient.h>
+#import <SignalServiceKit/TSStorageManager.h>
 
 NS_ASSUME_NONNULL_BEGIN
 
+@interface SignalAccount ()
+
+@property (nonatomic, nullable) SignalRecipient *signalRecipient;
+
+// This property may be modified after construction, so it should
+// only be modified on the main thread.
+@property (nonatomic) NSString *recipientId;
+
+@end
+
+#pragma mark -
+
 @implementation SignalAccount
 
-- (NSString *)recipientId
+- (instancetype)initWithSignalRecipient:(SignalRecipient *)signalRecipient
 {
-    OWSAssert(self.signalRecipient);
+    if (self = [super init]) {
+        OWSAssert(signalRecipient);
+
+        _signalRecipient = signalRecipient;
+        _recipientId = signalRecipient.uniqueId;
+    }
+    return self;
+}
+
+- (instancetype)initWithRecipientId:(NSString *)recipientId
+{
+    if (self = [super init]) {
+        OWSAssert(recipientId.length > 0);
+
+        _recipientId = recipientId;
+    }
+    return self;
+}
+
+- (nullable SignalRecipient *)signalRecipient
+{
+    OWSAssert([NSThread isMainThread]);
+
+    if (!_signalRecipient) {
+        [[TSStorageManager sharedManager].dbConnection readWithBlock:^(YapDatabaseReadTransaction *transaction) {
+            _signalRecipient =
+                [SignalRecipient recipientWithTextSecureIdentifier:self.recipientId withTransaction:transaction];
+        }];
+    }
 
-    return self.signalRecipient.uniqueId;
+    return _signalRecipient;
 }
 
 @end

Signal/src/contact/OWSContactsManager.m

@@ -216,25 +216,21 @@ void onAddressBookChanged(ABAddressBookRef notifyAddressBook, CFDictionaryRef in
 
         NSArray<SignalRecipient *> *signalRecipients = contact.signalRecipients;
         for (SignalRecipient *signalRecipient in contact.signalRecipients) {
-
-            if (signalRecipients.count == 1) {
-                SignalAccount *signalAccount = [SignalAccount new];
-                signalAccount.signalRecipient = signalRecipient;
+            for (NSString *recipientId in
+                [contact.textSecureIdentifiers sortedArrayUsingSelector:@selector(compare:)]) {
+                SignalAccount *signalAccount = [[SignalAccount alloc] initWithSignalRecipient:signalRecipient];
                 signalAccount.contact = contact;
-                signalAccountMap[signalAccount.recipientId] = signalAccount;
-                [signalAccounts addObject:signalAccount];
-            } else if (contact.textSecureIdentifiers.count > 1) {
-                for (NSString *recipientId in
-                    [contact.textSecureIdentifiers sortedArrayUsingSelector:@selector(compare:)]) {
-                    SignalAccount *signalAccount = [SignalAccount new];
-                    signalAccount.signalRecipient = signalRecipient;
-                    signalAccount.contact = contact;
+                if (signalRecipients.count > 1) {
                     signalAccount.isMultipleAccountContact = YES;
                     signalAccount.multipleAccountLabel =
                         [[self class] accountLabelForContact:contact recipientId:recipientId];
-                    signalAccountMap[signalAccount.recipientId] = signalAccount;
-                    [signalAccounts addObject:signalAccount];
                 }
+                if (signalAccountMap[signalAccount.recipientId]) {
+                    DDLogInfo(@"Ignoring duplicate contact: %@, %@", signalAccount.recipientId, contact.fullName);
+                    continue;
+                }
+                signalAccountMap[signalAccount.recipientId] = signalAccount;
+                [signalAccounts addObject:signalAccount];
             }
         }
     }
@@ -441,7 +437,8 @@ void onAddressBookChanged(ABAddressBookRef notifyAddressBook, CFDictionaryRef in
     NSArray *filteredContacts = [sortedPeople filteredArrayUsingPredicate:predicate];
 
     return [filteredContacts map:^id(id item) {
-      return [self contactForRecord:(__bridge ABRecordRef)item];
+        Contact *contact = [self contactForRecord:(__bridge ABRecordRef)item];
+        return contact;
     }];
 }
 

Signal/src/util/ObservableValue.m

@@ -95,6 +95,7 @@
       }
     }];
 }
+
 - (void)adjustValue:(id (^)(id))adjustment {
     ows_require(adjustment != nil);
     [self queueRun:^{