// Copyright 2018 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 CONTENT_PUBLIC_BROWSER_AUTHENTICATOR_REQUEST_CLIENT_DELEGATE_H_
#define CONTENT_PUBLIC_BROWSER_AUTHENTICATOR_REQUEST_CLIENT_DELEGATE_H_

#include <string>

#include "base/callback_forward.h"
#include "base/macros.h"
#include "base/optional.h"
#include "build/build_config.h"
#include "content/common/content_export.h"
#include "device/fido/fido_request_handler_base.h"
#include "device/fido/fido_transport_protocol.h"

#if defined(OS_MACOSX)
#include "device/fido/mac/authenticator_config.h"
#endif

namespace device {
class FidoAuthenticator;
}

namespace content {

// Interface that the embedder should implement to provide the //content layer
// with embedder-specific configuration for a single Web Authentication API [1]
// request serviced in a given RenderFrame.
//
// [1]: See https://www.w3.org/TR/webauthn/.
class CONTENT_EXPORT AuthenticatorRequestClientDelegate
    : public device::FidoRequestHandlerBase::Observer {
 public:
  // Failure reasons that might be of interest to the user, so the embedder may
  // decide to inform the user.
  enum class InterestingFailureReason {
    kTimeout,
    kKeyNotRegistered,
    kKeyAlreadyRegistered,
    kSoftPINBlock,
    kHardPINBlock,
  };

  AuthenticatorRequestClientDelegate();
  ~AuthenticatorRequestClientDelegate() override;

  // Called when the request fails for the given |reason|. Embedders may return
  // true if they want AuthenticatorImpl to hold off from resolving the WebAuthn
  // request with an error, e.g. because they want the user to dismiss an error
  // dialog first. In this case, embedders *must* eventually invoke the
  // FidoRequestHandlerBase::CancelCallback in order to resolve the request.
  // Returning false causes AuthenticatorImpl to resolve the request with the
  // error right away.
  virtual bool DoesBlockRequestOnFailure(InterestingFailureReason reason);

  // Supplies callbacks that the embedder can invoke to initiate certain
  // actions, namely: initiate BLE pairing process, cancel WebAuthN request, and
  // dispatch request to connected authenticators.
  virtual void RegisterActionCallbacks(
      base::OnceClosure cancel_callback,
      device::FidoRequestHandlerBase::RequestCallback request_callback,
      base::RepeatingClosure bluetooth_adapter_power_on_callback,
      device::FidoRequestHandlerBase::BlePairingCallback ble_pairing_callback);

  // Returns true if the given relying party ID is permitted to receive
  // individual attestation certificates. This:
  //  a) triggers a signal to the security key that returning individual
  //     attestation certificates is permitted, and
  //  b) skips any permission prompt for attestation.
  virtual bool ShouldPermitIndividualAttestation(
      const std::string& relying_party_id);

  // Invokes |callback| with |true| if the given relying party ID is permitted
  // to receive attestation certificates from a device. Otherwise invokes
  // |callback| with |false|.
  //
  // Since these certificates may uniquely identify the authenticator, the
  // embedder may choose to show a permissions prompt to the user, and only
  // invoke |callback| afterwards. This may hairpin |callback|.
  virtual void ShouldReturnAttestation(const std::string& relying_party_id,
                                       base::OnceCallback<void(bool)> callback);

  // Returns whether the WebContents corresponding to |render_frame_host| is the
  // active tab in the focused window. We do not want to allow
  // authenticatorMakeCredential operations to be triggered by background tabs.
  //
  // Note that the default implementation of this function, and the
  // implementation in ChromeContentBrowserClient for Android, return |true| so
  // that testing is possible.
  virtual bool IsFocused();

#if defined(OS_MACOSX)
  using TouchIdAuthenticatorConfig = device::fido::mac::AuthenticatorConfig;

  // Returns configuration data for the built-in Touch ID platform
  // authenticator. May return nullopt if the authenticator is not used or not
  // available.
  virtual base::Optional<TouchIdAuthenticatorConfig>
  GetTouchIdAuthenticatorConfig() const;
#endif

  // Saves transport type the user used during WebAuthN API so that the
  // WebAuthN UI will default to the same transport type during next API call.
  virtual void UpdateLastTransportUsed(device::FidoTransportProtocol transport);

  // Disables the UI (needed in cases when called by other components, like
  // cryptotoken).
  virtual void DisableUI();

  virtual bool IsWebAuthnUIEnabled();

  // device::FidoRequestHandlerBase::Observer:
  void OnTransportAvailabilityEnumerated(
      device::FidoRequestHandlerBase::TransportAvailabilityInfo data) override;
  // If true, the request handler will defer dispatch of its request onto the
  // given authenticator to the embedder. The embedder needs to call
  // |StartAuthenticatorRequest| when it wants to initiate request dispatch.
  //
  // This method is invoked before |FidoAuthenticatorAdded|, and may be
  // invoked multiple times for the same authenticator. Depending on the
  // result, the request handler might decide not to make the authenticator
  // available, in which case it never gets passed to
  // |FidoAuthenticatorAdded|.
  bool EmbedderControlsAuthenticatorDispatch(
      const device::FidoAuthenticator& authenticator) override;
  void BluetoothAdapterPowerChanged(bool is_powered_on) override;
  void FidoAuthenticatorAdded(
      const device::FidoAuthenticator& authenticator) override;
  void FidoAuthenticatorRemoved(base::StringPiece device_id) override;
  void FidoAuthenticatorIdChanged(base::StringPiece old_authenticator_id,
                                  std::string new_authenticator_id) override;
  void FidoAuthenticatorPairingModeChanged(base::StringPiece authenticator_id,
                                           bool is_in_pairing_mode) override;
  void CollectPIN(
      base::Optional<int> attempts,
      base::OnceCallback<void(std::string)> provide_pin_cb) override;
  void FinishCollectPIN() override;

 private:
  DISALLOW_COPY_AND_ASSIGN(AuthenticatorRequestClientDelegate);
};

}  // namespace content

#endif  // CONTENT_PUBLIC_BROWSER_AUTHENTICATOR_REQUEST_CLIENT_DELEGATE_H_