Add a database view for dynamic interactions.

// FREEBIE

src/Messages/Interactions/TSInteraction.h

@@ -35,6 +35,14 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (nullable NSDate *)receiptDateForSorting;
 
+// "Dynamic" interactions are not messages or static events (like
+// info messages, error messages, etc.).  They are interactions
+// created, updated and deleted by the views.
+//
+// These include block offers, "add to contact" offers,
+// unseen message indicators, etc.
+- (BOOL)isDynamicInteraction;
+
 @end
 
 NS_ASSUME_NONNULL_END

src/Messages/Interactions/TSInteraction.m

@@ -109,6 +109,11 @@ NS_ASSUME_NONNULL_BEGIN
     [fetchedThread updateWithLastMessage:self transaction:transaction];
 }
 
+- (BOOL)isDynamicInteraction
+{
+    return NO;
+}
+
 @end
 
 NS_ASSUME_NONNULL_END

src/Messages/OWSAddToContactsOfferMessage.m

@@ -42,6 +42,11 @@ NS_ASSUME_NONNULL_BEGIN
     return self.date;
 }
 
+- (BOOL)isDynamicInteraction
+{
+    return YES;
+}
+
 @end
 
 NS_ASSUME_NONNULL_END

src/Messages/OWSUnknownContactBlockOfferMessage.m

@@ -44,6 +44,11 @@ NS_ASSUME_NONNULL_BEGIN
     return self.date;
 }
 
+- (BOOL)isDynamicInteraction
+{
+    return YES;
+}
+
 @end
 
 NS_ASSUME_NONNULL_END

src/Storage/TSDatabaseView.h

@@ -1,9 +1,5 @@
 //
-//  TSDatabaseView.h
-//  TextSecureKit
-//
-//  Created by Frederic Jacobs on 17/11/14.
-//  Copyright (c) 2014 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2017 Open Whisper Systems. All rights reserved.
 //
 
 #import <Foundation/Foundation.h>
@@ -19,11 +15,13 @@ extern NSString *TSSecondaryDevicesGroup;
 extern NSString *TSThreadDatabaseViewExtensionName;
 extern NSString *TSMessageDatabaseViewExtensionName;
 extern NSString *TSUnreadDatabaseViewExtensionName;
+extern NSString *TSDynamicMessagesDatabaseViewExtensionName;
 extern NSString *TSSecondaryDevicesDatabaseViewExtensionName;
 
 + (BOOL)registerThreadDatabaseView;
 + (BOOL)registerBuddyConversationDatabaseView;
 + (BOOL)registerUnreadDatabaseView;
++ (BOOL)registerDynamicMessagesDatabaseView;
 + (void)asyncRegisterSecondaryDevicesDatabaseView;
 
 @end

src/Storage/TSDatabaseView.m

@@ -22,6 +22,7 @@ NSString *TSSecondaryDevicesGroup = @"TSSecondaryDevicesGroup";
 NSString *TSThreadDatabaseViewExtensionName  = @"TSThreadDatabaseViewExtensionName";
 NSString *TSMessageDatabaseViewExtensionName = @"TSMessageDatabaseViewExtensionName";
 NSString *TSUnreadDatabaseViewExtensionName  = @"TSUnreadDatabaseViewExtensionName";
+NSString *TSDynamicMessagesDatabaseViewExtensionName = @"TSDynamicMessagesDatabaseViewExtensionName";
 NSString *TSSecondaryDevicesDatabaseViewExtensionName = @"TSSecondaryDevicesDatabaseViewExtensionName";
 
 @implementation TSDatabaseView
@@ -58,6 +59,41 @@ NSString *TSSecondaryDevicesDatabaseViewExtensionName = @"TSSecondaryDevicesData
         [[TSStorageManager sharedManager].database registerExtension:view withName:TSUnreadDatabaseViewExtensionName];
 }
 
++ (BOOL)registerDynamicMessagesDatabaseView
+{
+    YapDatabaseView *existingView =
+        [[TSStorageManager sharedManager].database registeredExtension:TSDynamicMessagesDatabaseViewExtensionName];
+    if (existingView) {
+        return YES;
+    }
+
+    YapDatabaseViewGrouping *viewGrouping = [YapDatabaseViewGrouping withObjectBlock:^NSString *(
+        YapDatabaseReadTransaction *transaction, NSString *collection, NSString *key, id object) {
+        if ([object isKindOfClass:[TSInteraction class]]) {
+            TSInteraction *interaction = (TSInteraction *)object;
+            if ([interaction isDynamicInteraction]) {
+                return interaction.uniqueThreadId;
+            }
+        } else {
+            OWSAssert(0);
+        }
+        return nil;
+    }];
+
+    YapDatabaseViewSorting *viewSorting = [self messagesSorting];
+
+    YapDatabaseViewOptions *options = [[YapDatabaseViewOptions alloc] init];
+    options.isPersistent = YES;
+    options.allowedCollections =
+        [[YapWhitelistBlacklist alloc] initWithWhitelist:[NSSet setWithObject:[TSInteraction collection]]];
+
+    YapDatabaseView *view =
+        [[YapDatabaseView alloc] initWithGrouping:viewGrouping sorting:viewSorting versionTag:@"1" options:options];
+
+    return [[TSStorageManager sharedManager].database registerExtension:view
+                                                               withName:TSDynamicMessagesDatabaseViewExtensionName];
+}
+
 + (BOOL)registerThreadDatabaseView {
     YapDatabaseView *threadView =
         [[TSStorageManager sharedManager].database registeredExtension:TSThreadDatabaseViewExtensionName];

src/Storage/TSStorageManager.m

@@ -199,6 +199,7 @@ static NSString *keychainDBPassAccount    = @"TSDatabasePass";
     [TSDatabaseView registerThreadDatabaseView];
     [TSDatabaseView registerBuddyConversationDatabaseView];
     [TSDatabaseView registerUnreadDatabaseView];
+    [TSDatabaseView registerDynamicMessagesDatabaseView];
     [self.database registerExtension:[TSDatabaseSecondaryIndexes registerTimeStampIndex] withName:@"idx"];
 
     // Register extensions which aren't essential for rendering threads async