[iOS] Implement add account and more button press actions.

Add button press actions for two of the four button styles for the
UserSigninViewController. The sign-in operations will be added in a
follow-up patch.

See go/chrome-ios-signin-migration for more information.

Bug: 971989
Change-Id: Id669d2a788dd85849b13e1c27021fc7442e6a63d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2064945
Commit-Queue: Nohemi Fernandez <fernandex@chromium.org>
Reviewed-by: Jérôme Lebel <jlebel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#743517}

ios/chrome/browser/ui/authentication/signin/user_signin/user_signin_coordinator.mm

@@ -69,19 +69,6 @@ using signin_metrics::PromoAction;
 
   [self.unifiedConsentCoordinator start];
 
-  self.addAccountSigninCoordinator = [SigninCoordinator
-      addAccountCoordinatorWithBaseViewController:self.viewController
-                                          browser:self.browser
-                                      accessPoint:self.accessPoint];
-
-  __weak UserSigninCoordinator* weakSelf = self;
-  self.addAccountSigninCoordinator.signinCompletion =
-      ^(SigninCoordinatorResult signinResult, ChromeIdentity* identity) {
-        if (signinResult == SigninCoordinatorResultSuccess) {
-          weakSelf.defaultIdentity = identity;
-        }
-      };
-
   // Display UnifiedConsentViewController within the host.
   self.viewController.unifiedConsentViewController =
       self.unifiedConsentCoordinator.viewController;
@@ -113,7 +100,7 @@ using signin_metrics::PromoAction;
 - (void)unifiedConsentCoordinatorDidTapOnAddAccount:
     (UnifiedConsentCoordinator*)coordinator {
   DCHECK_EQ(self.unifiedConsentCoordinator, coordinator);
-  [self.addAccountSigninCoordinator start];
+  [self userSigninViewControllerDidTapOnAddAccount];
 }
 
 - (void)unifiedConsentCoordinatorNeedPrimaryButtonUpdate:
@@ -128,4 +115,26 @@ using signin_metrics::PromoAction;
   return self.unifiedConsentCoordinator.selectedIdentity != nil;
 }
 
+- (void)userSigninViewControllerDidTapOnAddAccount {
+  self.addAccountSigninCoordinator = [SigninCoordinator
+      addAccountCoordinatorWithBaseViewController:self.viewController
+                                          browser:self.browser
+                                      accessPoint:self.accessPoint];
+
+  __weak UserSigninCoordinator* weakSelf = self;
+  self.addAccountSigninCoordinator.signinCompletion =
+      ^(SigninCoordinatorResult signinResult, ChromeIdentity* identity) {
+        if (signinResult == SigninCoordinatorResultSuccess) {
+          weakSelf.unifiedConsentCoordinator.selectedIdentity = identity;
+          [weakSelf.addAccountSigninCoordinator stop];
+          weakSelf.addAccountSigninCoordinator = nil;
+        }
+      };
+  [self.addAccountSigninCoordinator start];
+}
+
+- (void)userSigninViewControllerDidScrollOnUnifiedConsent {
+  [self.unifiedConsentCoordinator scrollToBottom];
+}
+
 @end

ios/chrome/browser/ui/authentication/signin/user_signin/user_signin_view_controller.h

@@ -9,9 +9,17 @@
 
 // Delegate that interacts with the user sign-in coordinator.
 @protocol UserSigninViewControllerDelegate
+
 // Returns whether the user has selected an identity from the unified consent
 // screen.
 - (BOOL)unifiedConsentCoordinatorHasIdentity;
+
+// Performs add account operation.
+- (void)userSigninViewControllerDidTapOnAddAccount;
+
+// Performs scroll operation on unified consent screen.
+- (void)userSigninViewControllerDidScrollOnUnifiedConsent;
+
 @end
 
 // View controller used to show sign-in UI.

ios/chrome/browser/ui/authentication/signin/user_signin/user_signin_view_controller.mm

@@ -44,7 +44,14 @@ const AuthenticationViewConstants kRegularConstants = {
     32,  // ButtonTopPadding
     32,  // ButtonBottomPadding
 };
-}
+
+// The style applied to a button type.
+enum AuthenticationButtonType {
+  AuthenticationButtonTypeMore,
+  AuthenticationButtonTypeAddAccount,
+  AuthenticationButtonTypeConfirmation,
+};
+}  // namespace
 
 @interface UserSigninViewController ()
 
@@ -80,16 +87,22 @@ const AuthenticationViewConstants kRegularConstants = {
     [self.confirmationButton setTitle:self.addAccountButtonTitle
                              forState:UIControlStateNormal];
     [self setConfirmationStylingWithButton:self.confirmationButton];
+    self.confirmationButton.tag = AuthenticationButtonTypeAddAccount;
   } else if (!self.hasUnifiedConsentScreenReachedBottom) {
     // User has not scrolled to the bottom of the user consent screen.
     // Display 'more' button.
     [self updateButtonAsMoreButton:self.confirmationButton];
+    self.confirmationButton.tag = AuthenticationButtonTypeMore;
   } else {
     // By default display 'Yes I'm in' button.
     [self.confirmationButton setTitle:self.confirmationButtonTitle
                              forState:UIControlStateNormal];
     [self setConfirmationStylingWithButton:self.confirmationButton];
+    self.confirmationButton.tag = AuthenticationButtonTypeConfirmation;
   }
+  [self.confirmationButton addTarget:self
+                              action:@selector(onConfirmationButtonPressed:)
+                    forControlEvents:UIControlEventTouchUpInside];
 }
 
 #pragma mark - UIViewController
@@ -203,18 +216,16 @@ const AuthenticationViewConstants kRegularConstants = {
   [self.skipSigninButton setTitle:self.skipSigninButtonTitle
                          forState:UIControlStateNormal];
   [self setSkipSigninStylingWithButton:self.skipSigninButton];
+  [self.skipSigninButton addTarget:self
+                            action:@selector(onSkipSigninButtonPressed:)
+                  forControlEvents:UIControlEventTouchUpInside];
 }
 
 // Sets up button properties and adds it to view.
 - (void)addSubviewWithButton:(UIButton*)button {
   button.titleLabel.font =
       [UIFont preferredFontForTextStyle:UIFontTextStyleSubheadline];
-
   [self.view addSubview:button];
-  [button addTarget:self
-                action:@selector(onButtonPressed:)
-      forControlEvents:UIControlEventTouchUpInside];
-
   button.translatesAutoresizingMaskIntoConstraints = NO;
 }
 
@@ -245,9 +256,28 @@ const AuthenticationViewConstants kRegularConstants = {
 
 #pragma mark - Events
 
-- (void)onButtonPressed:(id)sender {
+- (void)onSkipSigninButtonPressed:(id)sender {
   // TODO(crbug.com/971989): Populate action.
   NOTIMPLEMENTED();
 }
 
+- (void)onConfirmationButtonPressed:(id)sender {
+  DCHECK_EQ(self.confirmationButton, sender);
+  switch (self.confirmationButton.tag) {
+    case AuthenticationButtonTypeMore: {
+      [self.delegate userSigninViewControllerDidScrollOnUnifiedConsent];
+      break;
+    }
+    case AuthenticationButtonTypeAddAccount: {
+      [self.delegate userSigninViewControllerDidTapOnAddAccount];
+      break;
+    }
+    case AuthenticationButtonTypeConfirmation: {
+      // TODO(crbug.com/971989): Populate action.
+      NOTIMPLEMENTED();
+      break;
+    }
+  }
+}
+
 @end