[Payments] Refactor into PaymentRequestState and Spec

components/payments/content/payment_request_state.h

Index: components/payments/content/payment_request_state.h
diff --git a/components/payments/content/payment_request_state.h b/components/payments/content/payment_request_state.h
new file mode 100644
index 0000000000000000000000000000000000000000..5c737c52538c79de58bfc3e0da00309775cb2060
--- /dev/null
+++ b/components/payments/content/payment_request_state.h
@@ -0,0 +1,141 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_PAYMENTS_CONTENT_PAYMENT_REQUEST_STATE_H_
+#define COMPONENTS_PAYMENTS_CONTENT_PAYMENT_REQUEST_STATE_H_
+
+#include "base/macros.h"
+#include "base/observer_list.h"
+#include "components/payments/content/payment_request.mojom.h"
+#include "components/payments/core/payment_instrument.h"
+
+namespace autofill {
+class AutofillProfile;
+class CreditCard;
+}  // namespace autofill
+
+namespace payments {
+
+class PaymentRequestSpec;
+
+// Keeps track of the information currently selected by the user and whether the
+// user is ready to pay. Uses information from the PaymentRequestSpec, which is
+// what the merchant has specified, as input into the "is ready to pay"
+// computation.
+class PaymentRequestState : public PaymentInstrument::Delegate {
+ public:
+  class Observer {
+   public:
+    // Called when the information (payment method, address/contact info,
+    // shipping option) changes.
+    virtual void OnSelectedInformationChanged() = 0;
+
+   protected:
+    virtual ~Observer() {}
+  };
+
+  class Delegate {
+   public:
+    virtual const std::string& GetApplicationLocale() = 0;

[anthonyvd, 2017/03/14 16:46:41]

Spec will also probably need the Locale, can we just pass it to both the ctors?

[Mathieu, 2017/03/14 18:05:39]

I don't think spec will need the locale... perhaps we can re-evaluate if it
does?

[anthonyvd, 2017/03/14 18:11:24]

I'm thinking of the shipping options provided by the website, for which we need
the locale to format the amount value. In any case, classes that use state and
spec need the locale, so they either need to get this delegate or call a
GetApplicationLocale function that just forwards the call to this one here. At
this point, might as well just pass locale to state's ctor (unless I'm missing
something and locale can change at runtime).

Not a big deal, I won't lose sleep if you feel strongly enough to leave it as-is
:)

[Mathieu, 2017/03/15 02:51:14]

You're right, I think I'll probably move the CurrencyFormatter somewhere (state
or spec or helper?) and provide the locale to that object at construction time
(since PaymentRequest has it).

+    virtual const std::vector<autofill::AutofillProfile*>&
+    GetBillingProfiles() = 0;
+
+    virtual void OnPaymentResponseAvailable(
+        mojom::PaymentResponsePtr response) = 0;
+
+   protected:
+    virtual ~Delegate() {}
+  };
+
+  PaymentRequestState(PaymentRequestSpec* spec, Delegate* delegate);
+  ~PaymentRequestState() override;
+
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
+  // PaymentInstrument::Delegate:
+  void OnInstrumentDetailsReady(
+      const std::string& method_name,
+      const std::string& stringified_details) override;
+  void OnInstrumentDetailsError() override {}
+
+  // Initiates the generation of the PaymentResponse. Callers should check
+  // |is_ready_to_pay|, which is inexpensive.
+  void GeneratePaymentResponse();
+
+  // Gets the Autofill Profile representing the shipping address or contact
+  // information currently selected for this PaymentRequest flow. Can return
+  // null.
+  autofill::AutofillProfile* selected_shipping_profile() const {
+    return selected_shipping_profile_;
+  }
+  autofill::AutofillProfile* selected_contact_profile() const {
+    return selected_contact_profile_;
+  }
+  // Returns the currently selected credit card for this PaymentRequest flow.
+  // It's not guaranteed to be complete. Returns nullptr if there is no selected
+  // card.
+  autofill::CreditCard* selected_credit_card() const {
+    return selected_credit_card_;
+  }
+  mojom::PaymentShippingOption* selected_shipping_option() {
+    return selected_shipping_option_;
+  }
+
+  // Setters to change the selected information. Will have the side effect of
+  // recomputing "is ready to pay" and notify observers.
+  void SetSelectedShippingProfile(autofill::AutofillProfile* profile);
+  void SetSelectedContactProfile(autofill::AutofillProfile* profile);
+  void SetSelectedCreditCard(autofill::CreditCard* card);
+  // Sets the initial selections and computes is ready to pay state, then
+  // notifies observers. Multiple arguments can be null.
+  void SetInitialSelections(autofill::AutofillProfile* shipping,
+                            autofill::AutofillProfile* contact,
+                            autofill::CreditCard* card);
+
+  bool is_ready_to_pay() { return is_ready_to_pay_; }
+
+ private:
+  // Uses the user-selected information as well as the merchant spec to update
+  // |is_ready_to_pay_| with the current state, by validating that all the
+  // required information is available. Will notify observers.
+  void UpdateIsReadyToPayAndNotifyObservers();
+
+  // Notifies all observers that selected information has changed.
+  void NotifyOnSelectedInformationChanged();
+
+  // Returns whether the selected data satisfies the PaymentDetails requirements
+  // (payment methods).
+  bool ArePaymentDetailsSatisfied();
+  // Returns whether the selected data satisfies the PaymentOptions requirements
+  // (contact info, shipping address).
+  bool ArePaymentOptionsSatisfied();
+
+  // Updates the selected_shipping_option based on the data passed to this
+  // payment request by the website. This will set selected_shipping_option_ to
+  // the last option marked selected in the options array.
+  void UpdateSelectedShippingOption();
+
+  bool is_ready_to_pay_;
+
+  PaymentRequestSpec* spec_;
+  Delegate* delegate_;
+
+  autofill::AutofillProfile* selected_shipping_profile_;
+  autofill::AutofillProfile* selected_contact_profile_;
+  autofill::CreditCard* selected_credit_card_;
+  // This is owned by |details_|, which is owned by this object and lives until
+  // |this| is destructed so it's safe to keep this raw pointer.
+  mojom::PaymentShippingOption* selected_shipping_option_;
+
+  std::unique_ptr<PaymentInstrument> selected_payment_instrument_;
+
+  base::ObserverList<Observer> observers_;
+
+  DISALLOW_COPY_AND_ASSIGN(PaymentRequestState);
+};
+
+}  // namespace payments
+
+#endif  // COMPONENTS_PAYMENTS_CONTENT_PAYMENT_REQUEST_STATE_H_