device/nfc/nfc_peer.h

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef DEVICE_NFC_NFC_PEER_H_
   6 #define DEVICE_NFC_NFC_PEER_H_
   7
   8 #include <map>
   9 #include <string>
  10 #include <vector>
  11
  12 #include "base/callback.h"
  13 #include "device/nfc/nfc_ndef_record.h"
  14
  15 namespace device {
  16
  17 // NfcPeer represents a remote NFC adapter that is available for P2P
  18 // communication with the local adapter. Instances of NfcPeer allow two
  19 // kinds of P2P interaction that is supported by NFC:
  20 //
  21 //    - NDEF. Specifically, reading NDEF records found on the peer device and
  22 //      pushing NDEF records to it (e.g. via SNEP or Android Beam), in the form
  23 //      of an NDEF message as specified by the NFC forum.
  24 //    - Initiating a handover. On platforms that support it, handover can be
  25 //      used to quickly bootstrap a Bluetooth or WiFi based connection between
  26 //      the two devices over NFC.
  27 class NfcPeer {
  28  public:
  29   // NFC handover types.
  30   enum HandoverType {
  31     kHandoverTypeBluetooth,
  32     kHandoverTypeWiFi
  33   };
  34
  35   // Interface for observing changes from NFC peer devices.
  36   class Observer {
  37    public:
  38     virtual ~Observer() {}
  39
  40     // This method will be called when an NDEF record |record| from the peer
  41     // device |peer| is received. Users can use this method to be notified of
  42     // new records on the device and when the initial set of records are
  43     // received from it, if any. All records received from |peer| can be
  44     // accessed by calling |peer->GetNdefMessage()|.
  45     virtual void RecordReceived(NfcPeer* peer, const NfcNdefRecord* record) {}
  46   };
  47
  48   // The ErrorCallback is used by methods to asynchronously report errors.
  49   typedef base::Closure ErrorCallback;
  50
  51   virtual ~NfcPeer();
  52
  53   // Adds and removes observers for events on this NFC peer. If monitoring
  54   // multiple peers, check the |peer| parameter of observer methods to
  55   // determine which peer is issuing the event.
  56   virtual void AddObserver(Observer* observer) = 0;
  57   virtual void RemoveObserver(Observer* observer) = 0;
  58
  59   // Returns the unique identifier assigned to this peer.
  60   virtual std::string GetIdentifier() const = 0;
  61
  62   // Returns all NDEF records that were received from the peer device in the
  63   // form of a NDEF message. If the returned NDEF message contains no records,
  64   // this only means that no records have yet been received from the device.
  65   // Users should use this method in conjunction with the Observer methods
  66   // to be notified when the records are ready.
  67   virtual const NfcNdefMessage& GetNdefMessage() const = 0;
  68
  69   // Sends the NDEF records contained in |message| to the peer device. On
  70   // success, |callback| will be invoked. On failure, |error_callback| will be
  71   // invoked.
  72   virtual void PushNdef(const NfcNdefMessage& message,
  73                         const base::Closure& callback,
  74                         const ErrorCallback& error_callback) = 0;
  75
  76   // Initiates WiFi or Bluetooth pairing with the NFC peer device based on
  77   // |handover_type|. On success, |callback| will be invoked. On failure,
  78   // |error_callback| will be invoked.
  79   virtual void StartHandover(HandoverType handover_type,
  80                              const base::Closure& callback,
  81                              const ErrorCallback& error_callback) = 0;
  82
  83  protected:
  84   NfcPeer();
  85
  86  private:
  87   DISALLOW_COPY_AND_ASSIGN(NfcPeer);
  88 };
  89
  90 }  // namespace device
  91
  92 #endif  // DEVICE_NFC_NFC_PEER_H_