nfc: Add native NFC API definitions.

device/nfc/nfc_peer.h

+// Copyright (c) 2013 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 DEVICE_NFC_NFC_PEER_H_
+#define DEVICE_NFC_NFC_PEER_H_
+
+#include <map>
+#include <string>
+#include <vector>
+
+#include "base/callback.h"
+#include "device/nfc/nfc_ndef_record.h"
+
+namespace device {
+
+// NfcPeer represents a remote NFC adapter that is available for P2P
+// communication with the local adapter. Instances of NfcPeer allow two
+// kinds of P2P interaction that is supported by NFC:
+//
+//    - NDEF. Specifically, reading NDEF records found on the peer device and
+//      pushing NDEF records to it (e.g. via SNEP or Android Beam), in the form
+//      of an NDEF message as specified by the NFC forum.
+//    - Initiating a handover. On platforms that support it, handover can be
+//      used to quickly bootstrap a Bluetooth or WiFi based connection between
+//      the two devices over NFC.
+class NfcPeer {
+ public:
+  // NFC handover types.
+  enum HandoverType {
+    kHandoverTypeBluetooth,
+    kHandoverTypeWiFi
+  };
+
+  // Interface for observing changes from NFC peer devices.
+  class Observer {
+   public:
+    virtual ~Observer() {}
+
+    // This method will be called when an NDEF message |message| from the peer
+    // device |peer| is received. Users can use this method to be notified of
+    // new records on the device and when the initial set of records are
+    // received from it, if any.
+    virtual void RecordsReceived(NfcPeer* peer,
+                                 const NfcNdefMessage& message) {}
+  };
+
+  // The ErrorCallback is used by methods to asynchronously report errors.
+  typedef base::Closure ErrorCallback;
+
+  virtual ~NfcPeer();
+
+  // Adds and removes observers for events on this NFC peer. If monitoring
+  // multiple peers, check the |peer| parameter of observer methods to
+  // determine which peer is issuing the event.
+  virtual void AddObserver(Observer* observer) = 0;
+  virtual void RemoveObserver(Observer* observer) = 0;
+
+  // Returns the unique identifier assigned to this peer.
+  virtual std::string GetIdentifier() const = 0;
+
+  // Returns all NDEF records that were received from the peer device in the
+  // form of a NDEF message. If the returned NDEF message contains no records,
+  // this only means that no records have yet been received from the device.
+  // Users should use this method in conjunction with the Observer methods
+  // to be notified when the records are ready.
+  virtual NfcNdefMessage GetNdefMessage() const = 0;
+
+  // Sends the NDEF records contained in |message| to the peer device. On
+  // success, |callback| will be invoked. On failure, |error_callback| will be
+  // invoked.
+  virtual void PushNdef(NfcNdefMessage* message,
+                        const base::Closure& callback,
+                        const ErrorCallback& error_callback) = 0;
+
+  // Initiates WiFi or Bluetooth pairing with the NFC peer device based on
+  // |handover_type|. On success, |callback| will be invoked. On failure,
+  // |error_callback| will be invoked.
+  virtual void StartHandover(HandoverType handover_type,
+                             const base::Closure& callback,
+                             const ErrorCallback& error_callback) = 0;
+
+ protected:
+  NfcPeer();
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(NfcPeer);
+};
+
+}  // namespace device
+
+#endif  // DEVICE_NFC_NFC_PEER_H_