1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130

// Copyright 2008, Google Inc.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
//  1. Redistributions of source code must retain the above copyright notice,
//     this list of conditions and the following disclaimer.
//  2. Redistributions in binary form must reproduce the above copyright notice,
//     this list of conditions and the following disclaimer in the documentation
//     and/or other materials provided with the distribution.
//  3. Neither the name of Google Inc. nor the names of its contributors may be
//     used to endorse or promote products derived from this software without
//     specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
// WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
// EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
// OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
// OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
// ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#ifndef GEARS_GEOLOCATION_NETWORK_LOCATION_PROVIDER_H__
#define GEARS_GEOLOCATION_NETWORK_LOCATION_PROVIDER_H__

#include "gears/base/common/common.h"
#include "gears/base/common/mutex.h"
#include "gears/base/common/string16.h"
#include "gears/base/common/thread.h"
#include "gears/geolocation/device_data_provider.h"
#include "gears/geolocation/location_provider.h"
#include "gears/geolocation/network_location_request.h"

class NetworkLocationProvider
    : public LocationProviderBase,
      public RadioDataProvider::ListenerInterface,
      public WifiDataProvider::ListenerInterface,
      public NetworkLocationRequest::ListenerInterface,
      public Thread {
 public:
  NetworkLocationProvider(const std::string16 &url,
                          const std::string16 &host_name,
                          const std::string16 &language);
  virtual ~NetworkLocationProvider();

  // Override LocationProviderBase implementation.
  virtual void RegisterListener(
      LocationProviderBase::ListenerInterface *listener,
      bool request_address);
  virtual void UnregisterListener(
    LocationProviderBase::ListenerInterface *listener);

  // LocationProviderBase implementation
  virtual void GetPosition(Position *position);

 private:
  // DeviceDataProvider::ListenerInterface implementation.
  virtual void DeviceDataUpdateAvailable(RadioDataProvider *provider);
  virtual void DeviceDataUpdateAvailable(WifiDataProvider *provider);

  // NetworkLocationRequest::ListenerInterface implementation.
  virtual void LocationResponseAvailable(const Position &position,
                                         bool server_error,
                                         const std::string16 &access_token);

  // Thread implementation
  virtual void Run();

  // Internal helper used by worker thread to make a network request
  bool MakeRequest();

  // Internal helper used by DeviceDataUpdateAvailable
  void DeviceDataUpdateAvailableImpl();

  // The network location request object and the url and host name it will use.
  NetworkLocationRequest *request_;
  std::string16 url_;
  std::string16 host_name_;

  // The device data providers
  RadioDataProvider *radio_data_provider_;
  WifiDataProvider *wifi_data_provider_;

  // The radio and wifi data, flags to indicate if each data set is complete,
  // and their guarding mutex.
  RadioData radio_data_;
  WifiData wifi_data_;
  bool is_radio_data_complete_;
  bool is_wifi_data_complete_;
  Mutex data_mutex_;

  // The timestamp for the latest device data update.
  int64 timestamp_;

  // Parameters for the network request
  bool request_address_;
  bool request_address_from_last_request_;
  std::string16 address_language_;

  // The current best position estimate and its guarding mutex
  Position position_;
  Mutex position_mutex_;

  // The event used to notify this object's (ie the network location provider)
  // worker thread about changes in available data, the network request status
  // and whether we're shutting down. The booleans are used to indicate what the
  // event signals.
  Event thread_notification_event_;
  bool is_shutting_down_;
  bool is_new_data_available_;
  bool is_last_request_complete_;
  bool is_new_listener_waiting_;

  // When the last request did not request an address, this stores any new
  // listeners which have been added and require an address to be requested.
  typedef std::set<LocationProviderBase::ListenerInterface*> ListenerSet;
  ListenerSet new_listeners_requiring_address_;
  Mutex new_listeners_requiring_address_mutex_;

  // The earliest timestamp at which the next request can be made, in
  // milliseconds.
  int64 earliest_next_request_time_;

  DISALLOW_EVIL_CONSTRUCTORS(NetworkLocationProvider);
};

#endif  // GEARS_GEOLOCATION_NETWORK_LOCATION_PROVIDER_H__