Target SiriIntents: Split IntentHandler into smaller files (#6203)

* Add protocol `ContactResolving`

* Let the `IntentHandler` implement `ContactResolving` (#6203)

Nothing has changed about the implementation itself; this prepares
the separation of this logic into a dedicated unit.

* Prepare the separation of the contact resolver from the intents handler (#6203)

* Move the implementation of `ContactResolving` to a dedicated class (#6203)

* Move `ContactResolver` to a dedicated file (#6203)

* Prepare the separation of the `StartAudioCallIntentHandler` from `IntentsHandler` (#6203)

* Move the implementation of `INStartAudioCallIntentHandling` to a dedicated class (#6203)

* Prepare the separation of the `StartVideoCallIntentHandler` from `IntentsHandler` (#6203)

* Move the implementation of `INStartVideoCallIntentHandling` to a dedicated class (#6203)

* Prepare the separation of the `SendMessageIntentHandler` from `IntentsHandler` (#6203)

* Move the implementation of `INSendMessageIntentHandling` to a dedicated class (#6203)

* Remove unused property (#6203)

* Return `nil` if the requested intent cannot be handled (#6203)

* Initialize the intent handlers _after_ everything else is configured (#6203)

In `init()`, there might be some configuration being done that is
required for the handlers.

* Add changelog entry

* Move curly braces in Objective-C to dedicated lines

This ensures that the code follows the style that is present in other Objective-C files.

Co-authored-by: Doug <6060466+pixlwave@users.noreply.github.com>

* Inject the `ContactResolver` into the intent handlers during initialization

In #6365, @pixlwave pointed out that

> If the resolver ever gained a cache or stored properties it would
> help keep the memory usage down in the extension

* Prefer forward-declaration over import in Objective-C header files

Per @pixlwave, this helps prevent build failures:

> We had random cycle errors while building a while back and it was
> eventually solved by removing all imports of `GeneratedInterface-Swift.h`
> in every [Objective-C header] file.

Co-authored-by: Doug <6060466+pixlwave@users.noreply.github.com>

SiriIntents/IntentHandlers/SendMessage/SendMessageIntentHandler.m

@@ -0,0 +1,161 @@
+// 
+// Copyright 2022 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#import "SendMessageIntentHandler.h"
+#import "ContactResolver.h"
+#import "MXKAccountManager.h"
+#import "GeneratedInterface-Swift.h"
+
+@interface SendMessageIntentHandler ()
+
+@property (nonatomic) id<ContactResolving> contactResolver;
+
+/**
+ The room that is currently being used to send a message. This is to ensure a
+ strong ref is maintained on the `MXRoom` until sending has completed.
+ */
+@property (nonatomic) MXRoom *selectedRoom;
+
+@end
+
+@implementation SendMessageIntentHandler
+
+- (instancetype)initWithContactResolver:(id<ContactResolving>)contactResolver
+{
+    if (self = [super init]) {
+        _contactResolver = contactResolver;
+    }
+    
+    return self;
+}
+
+#pragma mark - INSendMessageIntentHandling
+
+- (void)resolveRecipientsForSendMessage:(INSendMessageIntent *)intent completion:(void (^)(NSArray<INSendMessageRecipientResolutionResult *> * _Nonnull))completion
+{
+    [self.contactResolver resolveContacts:intent.recipients withCompletion:completion];
+}
+
+- (void)resolveContentForSendMessage:(INSendMessageIntent *)intent withCompletion:(void (^)(INStringResolutionResult * _Nonnull))completion
+{
+    NSString *message = intent.content;
+    if (message && ![message isEqualToString:@""])
+        completion([INStringResolutionResult successWithResolvedString:message]);
+    else
+        completion([INStringResolutionResult needsValue]);
+}
+
+- (void)confirmSendMessage:(INSendMessageIntent *)intent completion:(void (^)(INSendMessageIntentResponse * _Nonnull))completion
+{
+    INSendMessageIntentResponse *response = nil;
+    
+    MXKAccount *account = [MXKAccountManager sharedManager].activeAccounts.firstObject;
+    if (account)
+    {
+        NSUserActivity *userActivity = [[NSUserActivity alloc] initWithActivityType:NSStringFromClass([INSendMessageIntent class])];
+        response = [[INSendMessageIntentResponse alloc] initWithCode:INSendMessageIntentResponseCodeReady userActivity:userActivity];
+    }
+    else
+    {
+        // User hasn't logged in
+        response = [[INSendMessageIntentResponse alloc] initWithCode:INSendMessageIntentResponseCodeFailureRequiringAppLaunch userActivity:nil];
+    }
+    
+    completion(response);
+}
+
+- (void)handleSendMessage:(INSendMessageIntent *)intent completion:(void (^)(INSendMessageIntentResponse * _Nonnull))completion
+{
+    void (^completeWithCode)(INSendMessageIntentResponseCode) = ^(INSendMessageIntentResponseCode code) {
+        NSUserActivity *userActivity = nil;
+        if (code == INSendMessageIntentResponseCodeSuccess)
+            userActivity = [[NSUserActivity alloc] initWithActivityType:NSStringFromClass([INSendMessageIntent class])];
+        INSendMessageIntentResponse *response = [[INSendMessageIntentResponse alloc] initWithCode:INSendMessageIntentResponseCodeSuccess
+                                                                                     userActivity:userActivity];
+        completion(response);
+    };
+    
+    INPerson *person = intent.recipients.firstObject;
+    if (person && person.customIdentifier)
+    {
+        MXKAccount *account = [MXKAccountManager sharedManager].activeAccounts.firstObject;
+        MXFileStore *fileStore = [[MXFileStore alloc] initWithCredentials:account.mxCredentials];
+        [fileStore.roomSummaryStore fetchAllSummaries:^(NSArray<id<MXRoomSummaryProtocol>> * _Nonnull summaries) {
+            NSString *roomID = person.customIdentifier;
+            
+            BOOL isEncrypted = NO;
+            for (id<MXRoomSummaryProtocol> summary in summaries)
+            {
+                if ([summary.roomId isEqualToString:roomID])
+                {
+                    isEncrypted = summary.isEncrypted;
+                    break;
+                }
+            }
+
+            if (isEncrypted)
+            {
+                [MXFileStore setPreloadOptions:0];
+
+                MXSession *session = [[MXSession alloc] initWithMatrixRestClient:account.mxRestClient];
+                MXWeakify(session);
+                [session setStore:fileStore success:^{
+                    MXStrongifyAndReturnIfNil(session);
+
+                    self.selectedRoom = [MXRoom loadRoomFromStore:fileStore withRoomId:roomID matrixSession:session];
+
+                    // Do not warn for unknown devices. We have cross-signing now
+                    session.crypto.warnOnUnknowDevices = NO;
+
+                    MXWeakify(self);
+                    [self.selectedRoom sendTextMessage:intent.content
+                                              threadId:nil
+                                               success:^(NSString *eventId) {
+                        completeWithCode(INSendMessageIntentResponseCodeSuccess);
+                        MXStrongifyAndReturnIfNil(self);
+                        self.selectedRoom = nil;
+                    } failure:^(NSError *error) {
+                        completeWithCode(INSendMessageIntentResponseCodeFailure);
+                        MXStrongifyAndReturnIfNil(self);
+                        self.selectedRoom = nil;
+                    }];
+
+                } failure:^(NSError *error) {
+                    completeWithCode(INSendMessageIntentResponseCodeFailure);
+                }];
+
+                return;
+            }
+            
+            [account.mxRestClient sendTextMessageToRoom:roomID
+                                               threadId:nil
+                                                   text:intent.content
+                                                success:^(NSString *eventId) {
+                completeWithCode(INSendMessageIntentResponseCodeSuccess);
+            }
+                                                failure:^(NSError *error) {
+                completeWithCode(INSendMessageIntentResponseCodeFailure);
+            }];
+            
+        }];
+    }
+    else
+    {
+        completeWithCode(INSendMessageIntentResponseCodeFailure);
+    }
+}
+
+@end