[CRD iOS] Refactor an interface for RemotingAuthorization

remoting/ios/facade/remoting_service.mm

Index: remoting/ios/facade/remoting_service.mm
diff --git a/remoting/ios/facade/remoting_service.mm b/remoting/ios/facade/remoting_service.mm
index 10096f18f6a3a2a0083ddfe0731485ed948b6343..5c5a8f6a48876dc41a6a9aafdd8b8e1e1a57b104 100644
--- a/remoting/ios/facade/remoting_service.mm
+++ b/remoting/ios/facade/remoting_service.mm
@@ -18,7 +18,6 @@
 #import "remoting/ios/facade/host_list_fetcher.h"
 #import "remoting/ios/facade/ios_client_runtime_delegate.h"
 #import "remoting/ios/facade/remoting_authentication.h"
-#import "remoting/ios/facade/remoting_service.h"
 #import "remoting/ios/keychain_wrapper.h"
 
 #include "base/i18n/time_formatting.h"
@@ -37,19 +36,19 @@ NSString* const kUserDidUpdate = @"kUserDidUpdate";
 NSString* const kUserInfo = @"kUserInfo";
 
 @interface RemotingService ()<RemotingAuthenticationDelegate> {
-  std::unique_ptr<remoting::OAuthTokenGetter> _tokenGetter;
+  id<RemotingAuthentication> _authentication;
   remoting::HostListFetcher* _hostListFetcher;
   remoting::IosClientRuntimeDelegate* _clientRuntimeDelegate;
+  BOOL _isHostListFetching;
 }
 @end
 
 @implementation RemotingService
 
-@synthesize authentication = _authentication;
 @synthesize hosts = _hosts;
 
 // RemotingService is a singleton.
-+ (RemotingService*)SharedInstance {
++ (RemotingService*)instance {
   static RemotingService* sharedInstance = nil;
   static dispatch_once_t guard;
   dispatch_once(&guard, ^{
@@ -61,10 +60,10 @@ NSString* const kUserInfo = @"kUserInfo";
 - (instancetype)init {
   self = [super init];
   if (self) {
-    _authentication = [[RemotingAuthentication alloc] init];
-    _authentication.delegate = self;
     _hosts = nil;
     _hostListFetcher = nil;
+    // TODO(yuweih): Maybe better to just cancel the previous request.
+    _isHostListFetching = NO;
     // TODO(nicholss): This might need a pointer back to the service.
     _clientRuntimeDelegate =
         new remoting::IosClientRuntimeDelegate();
@@ -76,6 +75,10 @@ NSString* const kUserInfo = @"kUserInfo";
 #pragma mark - RemotingService Implementation
 
 - (void)startHostListFetchWith:(NSString*)accessToken {
+  if (_isHostListFetching) {
+    return;
+  }
+  _isHostListFetching = YES;
   if (!_hostListFetcher) {
     _hostListFetcher = new remoting::HostListFetcher(
         remoting::ChromotingClientRuntime::GetInstance()->url_requester());
@@ -116,6 +119,7 @@ NSString* const kUserInfo = @"kUserInfo";
         }
         _hosts = hosts;
         [self hostListUpdated];
+        _isHostListFetching = NO;
       }));
 }
 
@@ -133,6 +137,7 @@ NSString* const kUserInfo = @"kUserInfo";
   NSDictionary* userInfo = nil;
   if (user) {
     userInfo = [NSDictionary dictionaryWithObject:user forKey:kUserInfo];
+    [self requestHostListFetch];
   } else {
     _hosts = nil;
     [self hostListUpdated];
@@ -159,13 +164,21 @@ NSString* const kUserInfo = @"kUserInfo";
 
 - (void)requestHostListFetch {
   [_authentication
-      callbackWithAccessToken:base::BindBlockArc(^(
-                                  remoting::OAuthTokenGetter::Status status,
-                                  const std::string& user_email,
-                                  const std::string& access_token) {
-        NSString* accessToken = base::SysUTF8ToNSString(access_token);
+      callbackWithAccessToken:^(RemotingAuthenticationStatus status,
+                                NSString* userEmail, NSString* accessToken) {
         [self startHostListFetchWith:accessToken];
-      })];
+      }];
+}
+
+- (void)setAuthentication:(id<RemotingAuthentication>)authentication {
+  DCHECK(_authentication == nil);
+  authentication.delegate = self;
+  _authentication = authentication;
+}
+
+- (id<RemotingAuthentication>)authentication {
+  DCHECK(_authentication != nil);
+  return _authentication;
 }
 
 @end