[Payments] Add the pay button, and control its enabled state

components/payments/content/payment_request.cc

Index: components/payments/content/payment_request.cc
diff --git a/components/payments/content/payment_request.cc b/components/payments/content/payment_request.cc
index 0a83cf2c5afd7ef3d4b6ffe48c37e57d90770c37..8eceeaed4c87383b4396fa71c90bf7aacb552b40 100644
--- a/components/payments/content/payment_request.cc
+++ b/components/payments/content/payment_request.cc
@@ -4,10 +4,13 @@
 
 #include "components/payments/content/payment_request.h"
 
+#include <algorithm>
 #include <unordered_map>
 #include <utility>
 
 #include "base/memory/ptr_util.h"
+#include "components/autofill/core/browser/autofill_data_util.h"
+#include "components/autofill/core/browser/field_types.h"
 #include "components/autofill/core/browser/personal_data_manager.h"
 #include "components/payments/content/payment_details_validation.h"
 #include "components/payments/content/payment_request_web_contents_manager.h"
@@ -26,6 +29,7 @@ PaymentRequest::PaymentRequest(
       delegate_(std::move(delegate)),
       manager_(manager),
       binding_(this, std::move(request)),
+      is_ready_to_pay_(false),
       selected_shipping_profile_(nullptr),
       selected_contact_profile_(nullptr),
       selected_credit_card_(nullptr) {
@@ -54,9 +58,11 @@ void PaymentRequest::Init(
   }
   client_ = std::move(client);
   details_ = std::move(details);
+  options_ = std::move(options);
   PopulateValidatedMethodData(method_data);
   PopulateProfileCache();
   SetDefaultProfileSelections();
+  UpdateIsReadyToPay();
 }
 
 void PaymentRequest::Show() {
@@ -103,6 +109,13 @@ void PaymentRequest::OnConnectionTerminated() {
   manager_->DestroyRequest(this);
 }
 
+void PaymentRequest::Pay() {
+  DCHECK(is_ready_to_pay_);
+
+  // TODO(mathp): Return the PaymentResponse to the |client_|.
+  UserCancelled();
+}
+
 CurrencyFormatter* PaymentRequest::GetOrCreateCurrencyFormatter(
     const std::string& currency_code,
     const std::string& currency_system,
@@ -241,4 +254,56 @@ void PaymentRequest::PopulateValidatedMethodData(
   }
 }
 
+void PaymentRequest::UpdateIsReadyToPay() {
+  is_ready_to_pay_ =
+      ArePaymentDetailsSatisfied() && ArePaymentOptionsSatisfied();
+}
+
+bool PaymentRequest::ArePaymentDetailsSatisfied() {
+  if (selected_credit_card_ == nullptr || !selected_credit_card_->IsValid())
+    return false;
+
+  const std::string basic_card_payment_type =
+      autofill::data_util::GetPaymentRequestData(selected_credit_card_->type())
+          .basic_card_payment_type;
+  return !supported_card_networks_.empty() &&
+         std::find(supported_card_networks_.begin(),
+                   supported_card_networks_.end(),
+                   basic_card_payment_type) != supported_card_networks_.end();
+}
+
+bool PaymentRequest::ArePaymentOptionsSatisfied() {
+  // TODO(mathp): Have a measure of shipping address completeness.
+  if (options_->request_shipping && selected_shipping_profile_ == nullptr)
+    return false;
+
+  // TODO(mathp): Make an encompassing class to validate contact info.
+  const std::string& app_locale = delegate_->GetApplicationLocale();
+  if (options_->request_payer_name &&
+      (selected_contact_profile_ == nullptr ||
+       selected_contact_profile_
+           ->GetInfo(autofill::AutofillType(autofill::NAME_FULL), app_locale)
+           .empty())) {
+    return false;
+  }
+  if (options_->request_payer_email &&
+      (selected_contact_profile_ == nullptr ||
+       selected_contact_profile_
+           ->GetInfo(autofill::AutofillType(autofill::EMAIL_ADDRESS),
+                     app_locale)
+           .empty())) {
+    return false;
+  }
+  if (options_->request_payer_phone &&
+      (selected_contact_profile_ == nullptr ||
+       selected_contact_profile_
+           ->GetInfo(autofill::AutofillType(autofill::PHONE_HOME_WHOLE_NUMBER),
+                     app_locale)
+           .empty())) {
+    return false;
+  }
+
+  return true;
+}
+
 }  // namespace payments