[FastCheckout] Implement FC delegate preconditions.

We check that:
* FC is shown once per page (reset on navigation).
* The clicked field is focusable and empty.
* There is at least 1 complete valid credit card and address on file.
* UI is available (RFH is active).
More checks might be added once the requirements are clarified.

Also we now hide the Autofill Popup when FC is to be shown.

Full context: go/fast-checkout-keyboard-hiding

Bug: 1334642
Change-Id: Ief25fb95bfdd980141d2b13be18a7c0a3197737b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3830023
Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Reviewed-by: Mohamed Amir Yosef <mamir@chromium.org>
Reviewed-by: Christoph Schwering <schwering@google.com>
Reviewed-by: Bo Liu <boliu@chromium.org>
Reviewed-by: Jan Keitel <jkeitel@google.com>
Commit-Queue: Norge Vizcay <vizcay@google.com>
Reviewed-by: Elizabeth Popova <lizapopova@google.com>
Cr-Commit-Position: refs/heads/main@{#1041540}

android_webview/browser/aw_autofill_client.cc

@@ -189,6 +189,26 @@ void AwAutofillClient::ScanCreditCard(CreditCardScanCallback callback) {
   NOTIMPLEMENTED();
 }
 
+bool AwAutofillClient::IsFastCheckoutSupported() {
+  return false;
+}
+
+bool AwAutofillClient::IsFastCheckoutTriggerForm(
+    const autofill::FormData& form,
+    const autofill::FormFieldData& field) {
+  return false;
+}
+
+bool AwAutofillClient::ShowFastCheckout(
+    base::WeakPtr<autofill::FastCheckoutDelegate> delegate) {
+  NOTREACHED();
+  return false;
+}
+
+void AwAutofillClient::HideFastCheckout() {
+  NOTREACHED();
+}
+
 bool AwAutofillClient::IsTouchToFillCreditCardSupported() {
   return false;
 }

android_webview/browser/aw_autofill_client.h

@@ -112,6 +112,12 @@ class AwAutofillClient : public autofill::AutofillClient,
       AddressProfileSavePromptCallback callback) override;
   bool HasCreditCardScanFeature() override;
   void ScanCreditCard(CreditCardScanCallback callback) override;
+  bool IsFastCheckoutSupported() override;
+  bool IsFastCheckoutTriggerForm(const autofill::FormData& form,
+                                 const autofill::FormFieldData& field) override;
+  bool ShowFastCheckout(
+      base::WeakPtr<autofill::FastCheckoutDelegate> delegate) override;
+  void HideFastCheckout() override;
   bool IsTouchToFillCreditCardSupported() override;
   bool ShowTouchToFillCreditCard(
       base::WeakPtr<autofill::TouchToFillDelegate> delegate) override;

chrome/browser/ui/autofill/chrome_autofill_client.cc

@@ -677,6 +677,32 @@ void ChromeAutofillClient::ScanCreditCard(CreditCardScanCallback callback) {
                                               std::move(callback));
 }
 
+bool ChromeAutofillClient::IsFastCheckoutSupported() {
+  // TODO(crbug.com/1334642): Implement.
+  NOTIMPLEMENTED();
+  return false;
+}
+
+bool ChromeAutofillClient::IsFastCheckoutTriggerForm(
+    const FormData& form,
+    const FormFieldData& field) {
+  // TODO(crbug.com/1334642): Implement.
+  NOTIMPLEMENTED();
+  return false;
+}
+
+bool ChromeAutofillClient::ShowFastCheckout(
+    base::WeakPtr<FastCheckoutDelegate> delegate) {
+  // TODO(crbug.com/1334642): Implement.
+  NOTIMPLEMENTED();
+  return false;
+}
+
+void ChromeAutofillClient::HideFastCheckout() {
+  // TODO(crbug.com/1334642): Implement.
+  NOTIMPLEMENTED();
+}
+
 bool ChromeAutofillClient::IsTouchToFillCreditCardSupported() {
 #if BUILDFLAG(IS_ANDROID)
   return base::FeatureList::IsEnabled(

chrome/browser/ui/autofill/chrome_autofill_client.h

@@ -29,6 +29,7 @@
 
 #if BUILDFLAG(IS_ANDROID)
 #include "chrome/browser/autofill/android/save_update_address_profile_flow_manager.h"
+#include "chrome/browser/fast_checkout/fast_checkout_client.h"
 #include "chrome/browser/touch_to_fill/payments/android/touch_to_fill_credit_card_controller.h"
 #include "chrome/browser/ui/android/autofill/save_card_message_controller_android.h"
 #include "components/autofill/core/browser/ui/payments/card_expiration_date_fix_flow_controller_impl.h"
@@ -170,6 +171,11 @@ class ChromeAutofillClient
       AddressProfileSavePromptCallback callback) override;
   bool HasCreditCardScanFeature() override;
   void ScanCreditCard(CreditCardScanCallback callback) override;
+  bool IsFastCheckoutSupported() override;
+  bool IsFastCheckoutTriggerForm(const FormData& form,
+                                 const FormFieldData& field) override;
+  bool ShowFastCheckout(base::WeakPtr<FastCheckoutDelegate> delegate) override;
+  void HideFastCheckout() override;
   bool IsTouchToFillCreditCardSupported() override;
   bool ShowTouchToFillCreditCard(
       base::WeakPtr<TouchToFillDelegate> delegate) override;

components/autofill/core/browser/BUILD.gn

@@ -816,6 +816,7 @@ source_set("unit_tests") {
     "data_model/credit_card_unittest.cc",
     "data_model/iban_unittest.cc",
     "data_model/phone_number_unittest.cc",
+    "fast_checkout_delegate_impl_unittest.cc",
     "field_filler_unittest.cc",
     "field_types_unittest.cc",
     "form_data_importer_unittest.cc",

components/autofill/core/browser/autofill_client.h

@@ -16,6 +16,7 @@
 #include "base/memory/weak_ptr.h"
 #include "base/types/strong_alias.h"
 #include "build/build_config.h"
+#include "components/autofill/core/browser/fast_checkout_delegate.h"
 #include "components/autofill/core/browser/payments/legal_message_line.h"
 #include "components/autofill/core/browser/payments/risk_data_loader.h"
 #include "components/autofill/core/browser/ui/popup_item_ids.h"
@@ -587,6 +588,26 @@ class AutofillClient : public RiskDataLoader {
   // HasCreditCardScanFeature() returns true.
   virtual void ScanCreditCard(CreditCardScanCallback callback) = 0;
 
+  // Returns true if the Fast Checkout feature is both supported by platform and
+  // enabled. Should be called before `ShowFastCheckout` or `HideFastCheckout`.
+  virtual bool IsFastCheckoutSupported() = 0;
+
+  // Returns true if the form is one of the trigger forms for Fast Checkout on
+  // the domain. Should be called before `ShowFastCheckout`.
+  virtual bool IsFastCheckoutTriggerForm(const FormData& form,
+                                         const FormFieldData& field) = 0;
+
+  // Shows the FastCheckout surface (for autofilling information during the
+  // checkout flow) and returns `true` on success. `delegate` will be notified
+  // of events. Should be called only if `IsFastCheckoutSupported` returns true.
+  virtual bool ShowFastCheckout(
+      base::WeakPtr<FastCheckoutDelegate> delegate) = 0;
+
+  // Hides the Fast Checkout surface (for autofilling information during the
+  // checkout flow) if one is currently shown. Should be called only if
+  // `IsFastCheckoutSupported` returns true.
+  virtual void HideFastCheckout() = 0;
+
   // Returns true if the Touch To Fill feature is both supported by platform and
   // enabled. Should be called before |ShowTouchToFillCreditCard| or
   // |HideTouchToFillCreditCard|.

components/autofill/core/browser/browser_autofill_manager.cc

@@ -1121,7 +1121,7 @@ void BrowserAutofillManager::OnAskForValuesToFillImpl(
 
   if (fast_checkout_delegate_->IsShowingFastCheckoutUI() ||
       (form_element_was_clicked &&
-       fast_checkout_delegate_->TryToShowFastCheckout(field))) {
+       fast_checkout_delegate_->TryToShowFastCheckout(form, field))) {
     // The Fast Checkout surface is shown, so abort showing regular Autofill UI.
     // Now the flow is controlled by the `fast_checkout_delegate_` instead
     // of `external_delegate_`.

components/autofill/core/browser/browser_autofill_manager_unittest.cc

@@ -192,7 +192,7 @@ class MockFastCheckoutDelegate : public FastCheckoutDelegate {
 
   MOCK_METHOD(bool,
               TryToShowFastCheckout,
-              (const FormFieldData& field),
+              (const FormData& form, const FormFieldData& field),
               (override));
   MOCK_METHOD(bool, IsShowingFastCheckoutUI, (), (const, override));
   MOCK_METHOD(void, HideFastCheckoutUI, (), (override));

components/autofill/core/browser/data_model/credit_card.cc

@@ -1146,10 +1146,20 @@ bool CreditCard::IsExpired(const base::Time& current_time) const {
                                           current_time);
 }
 
+bool CreditCard::masked() const {
+  return record_type() == CreditCard::MASKED_SERVER_CARD ||
+         record_type() == CreditCard::VIRTUAL_CARD;
+}
+
 bool CreditCard::ShouldUpdateExpiration() const {
   return IsExpired(AutofillClock::Now());
 }
 
+bool CreditCard::IsCompleteValidCard() const {
+  return !IsExpired(AutofillClock::Now()) && HasNameOnCard() &&
+         (masked() || HasValidCardNumber());
+}
+
 // So we can compare CreditCards with EXPECT_EQ().
 std::ostream& operator<<(std::ostream& os, const CreditCard& credit_card) {
   return os << base::UTF16ToUTF8(credit_card.Label()) << " "

components/autofill/core/browser/data_model/credit_card.h

@@ -250,9 +250,17 @@ class CreditCard : public AutofillDataModel {
   // Returns whether the card is expired based on |current_time|.
   bool IsExpired(const base::Time& current_time) const;
 
+  // Returns whether the card is a masked card. Such cards will only have
+  // the last 4 digits of the card number.
+  bool masked() const;
+
   // Whether the card expiration date should be updated.
   bool ShouldUpdateExpiration() const;
 
+  // Complete = contains number, expiration date and name on card.
+  // Valid = unexpired with valid number format.
+  bool IsCompleteValidCard() const;
+
   const std::string& billing_address_id() const { return billing_address_id_; }
   void set_billing_address_id(const std::string& id) {
     billing_address_id_ = id;

components/autofill/core/browser/fast_checkout_delegate.h

@@ -22,7 +22,8 @@ class FastCheckoutDelegate {
 
   // Checks whether FastCheckout is eligible for the given web form data. On
   // success triggers the corresponding surface and returns `true`.
-  virtual bool TryToShowFastCheckout(const FormFieldData& field) = 0;
+  virtual bool TryToShowFastCheckout(const FormData& form,
+                                     const FormFieldData& field) = 0;
 
   // Returns whether the FC surface is currently being shown.
   virtual bool IsShowingFastCheckoutUI() const = 0;

components/autofill/core/browser/fast_checkout_delegate_impl.cc

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "components/autofill/core/browser/fast_checkout_delegate_impl.h"
+#include "components/autofill/core/browser/browser_autofill_manager.h"
 
 namespace autofill {
 
@@ -14,10 +15,34 @@ FastCheckoutDelegateImpl::FastCheckoutDelegateImpl(
 
 FastCheckoutDelegateImpl::~FastCheckoutDelegateImpl() = default;
 
+// TODO(crbug.com/1334642): Add metrics to record reasons why FC is not shown.
 bool FastCheckoutDelegateImpl::TryToShowFastCheckout(
+    const FormData& form,
     const FormFieldData& field) {
-  // TODO(crbug.com/1334642): Implement.
-  return false;
+  // Trigger only on supported platforms.
+  if (!manager_->client()->IsFastCheckoutSupported())
+    return false;
+  // Trigger only if the form is a trigger form for FC.
+  if (!manager_->client()->IsFastCheckoutTriggerForm(form, field))
+    return false;
+  // Trigger only if not shown before.
+  if (fast_checkout_state_ != FastCheckoutState::kNotShownYet)
+    return false;
+  // Trigger only on focusable empty fields.
+  if (!field.is_focusable || !field.value.empty())
+    return false;
+  // Trigger only if the UI is available.
+  if (!manager_->driver()->CanShowAutofillUi())
+    return false;
+
+  // Finally try showing the surface.
+  if (!manager_->client()->ShowFastCheckout(GetWeakPtr()))
+    return false;
+
+  fast_checkout_state_ = FastCheckoutState::kIsShowing;
+  manager_->client()->HideAutofillPopup(
+      PopupHidingReason::kOverlappingWithFastCheckoutSurface);
+  return true;
 }
 
 bool FastCheckoutDelegateImpl::IsShowingFastCheckoutUI() const {
@@ -28,12 +53,17 @@ void FastCheckoutDelegateImpl::OnFastCheckoutUIHidden() {
   fast_checkout_state_ = FastCheckoutState::kWasShown;
 }
 
+// TODO(crbug.com/1348538): Create a central point for TTF/FC hiding decision.
 void FastCheckoutDelegateImpl::HideFastCheckoutUI() {
-  // TODO(crbug.com/1334642): Implement.
+  if (IsShowingFastCheckoutUI()) {
+    manager_->client()->HideFastCheckout();
+    fast_checkout_state_ = FastCheckoutState::kWasShown;
+  }
 }
 
 void FastCheckoutDelegateImpl::Reset() {
-  // TODO(crbug.com/1334642): Implement.
+  HideFastCheckoutUI();
+  fast_checkout_state_ = FastCheckoutState::kNotShownYet;
 }
 
 base::WeakPtr<FastCheckoutDelegateImpl> FastCheckoutDelegateImpl::GetWeakPtr() {

components/autofill/core/browser/fast_checkout_delegate_impl.h

@@ -19,7 +19,8 @@ class FastCheckoutDelegateImpl : public FastCheckoutDelegate {
   ~FastCheckoutDelegateImpl() override;
 
   // FastCheckoutDelegate:
-  bool TryToShowFastCheckout(const FormFieldData& field) override;
+  bool TryToShowFastCheckout(const FormData& form,
+                             const FormFieldData& field) override;
   bool IsShowingFastCheckoutUI() const override;
   void HideFastCheckoutUI() override;
   void OnFastCheckoutUIHidden() override;