// Copyright 2008, Google Inc.
//
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//
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//
// A location provider provides position information from a particular source
// (GPS, network etc). The GearsGeolocation object uses a set of location
// providers to obtain a position fix.
//
// This file declares a base class to be used by all location providers.
// Primarily, this class declares interface methods to be implemented by derived
// classes. It also provides ref-counting.

#ifndef GEARS_GEOLOCATION_LOCATION_PROVIDER_H__
#define GEARS_GEOLOCATION_LOCATION_PROVIDER_H__

#include "gears/base/common/scoped_refptr.h"
#include "gears/base/common/string16.h"

struct Position;

// The base class used by all location providers.
class LocationProviderBase : public RefCounted {
 public:
  class ListenerInterface {
   public:
    virtual bool LocationUpdateAvailable(LocationProviderBase *provider,
                                         const Position &position) = 0;
    virtual ~ListenerInterface() {}
  };

  virtual ~LocationProviderBase() {}

  // Interface methods.
  virtual void SetListener(ListenerInterface *listener) = 0;
  // This should call back to ListenerInterface::LocationUpdateAvailable.
  virtual bool GetCurrentPosition() = 0;
};

// Factory functions for the various types of location provider to abstract over
// the platform-dependent implementations.
#ifdef USING_CCTESTS
LocationProviderBase *NewMockLocationProvider();
#endif
LocationProviderBase *NewGpsLocationProvider();
LocationProviderBase *NewNetworkLocationProvider(
    const std::string16 &url, const std::string16 &host_name);

#endif  // GEARS_GEOLOCATION_LOCATION_PROVIDER_H__