extensions/browser/api/webcam_private/visca_webcam.h

   1 // Copyright 2015 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 EXTENSIONS_BROWSER_API_WEBCAM_PRIVATE_VISCA_WEBCAM_H_
   6 #define EXTENSIONS_BROWSER_API_WEBCAM_PRIVATE_VISCA_WEBCAM_H_
   7
   8 #include <deque>
   9
  10 #include "base/callback.h"
  11 #include "base/memory/weak_ptr.h"
  12 #include "extensions/browser/api/serial/serial_connection.h"
  13 #include "extensions/browser/api/webcam_private/webcam.h"
  14 #include "extensions/common/api/serial.h"
  15
  16 namespace extensions {
  17
  18 class ViscaWebcam : public Webcam {
  19  public:
  20   ViscaWebcam(const std::string& path, const std::string& extension_id);
  21
  22   using OpenCompleteCallback = base::Callback<void(bool)>;
  23
  24   // Open and initialize the web camera. This is done by the following three
  25   // steps (in order): 1. Open the serial port;  2. Request address; 3. Clear
  26   // the command buffer. After these three steps completes, |open_callback| will
  27   // be called.
  28   void Open(const OpenCompleteCallback& open_callback);
  29
  30  private:
  31   ~ViscaWebcam() override;
  32
  33   enum CommandType {
  34     COMMAND,
  35     INQUIRY_PAN,
  36     INQUIRY_TILT,
  37     INQUIRY_PAN_TILT,
  38     INQUIRY_ZOOM,
  39   };
  40
  41   using CommandCompleteCallback =
  42       base::Callback<void(bool, const std::vector<char>&)>;
  43
  44   void OpenOnIOThread(const OpenCompleteCallback& open_callback);
  45   // Callback function that will be called after the serial connection has been
  46   // opened successfully.
  47   void OnConnected(const OpenCompleteCallback& open_callback, bool success);
  48   // Callback function that will be called after the address has been set
  49   // successfully.
  50   void OnAddressSetCompleted(const OpenCompleteCallback& open_callback,
  51                              bool success,
  52                              const std::vector<char>& response);
  53   // Callback function that will be called after the command buffer has been
  54   // cleared successfully.
  55   void OnClearAllCompleted(const OpenCompleteCallback& open_callback,
  56                            bool success,
  57                            const std::vector<char>& response);
  58
  59   // Send or queue a command and wait for the camera's response.
  60   void Send(const std::vector<char>& command,
  61             const CommandCompleteCallback& callback);
  62   void OnSendCompleted(const CommandCompleteCallback& callback,
  63                        int bytes_sent,
  64                        api::serial::SendError error);
  65   void ReceiveLoop(const CommandCompleteCallback& callback);
  66   void OnReceiveCompleted(const CommandCompleteCallback& callback,
  67                           const std::vector<char>& data,
  68                           api::serial::ReceiveError error);
  69   // Callback function that will be called after the send and reply of a command
  70   // are both completed. Update |value| according to |type| and |response| if
  71   // necessory.
  72   void OnCommandCompleted(CommandType type,
  73                           int* value,
  74                           bool success,
  75                           const std::vector<char>& response);
  76
  77   // Webcam Overrides:
  78   void Reset(bool pan, bool tilt, bool zoom) override;
  79   bool GetPan(int* value) override;
  80   bool GetTilt(int* value) override;
  81   bool GetZoom(int* value) override;
  82   bool SetPan(int value) override;
  83   bool SetTilt(int value) override;
  84   bool SetZoom(int value) override;
  85   bool SetPanDirection(PanDirection direction) override;
  86   bool SetTiltDirection(TiltDirection direction) override;
  87
  88   const std::string path_;
  89   const std::string extension_id_;
  90
  91   scoped_ptr<SerialConnection> serial_connection_;
  92
  93   // Stores the response for the current command.
  94   std::vector<char> data_buffer_;
  95   // Queues commands till the current command completes.
  96   std::deque<std::pair<std::vector<char>, CommandCompleteCallback>> commands_;
  97
  98   // Visca webcam always get/set pan-tilt together. |pan| and |tilt| are used to
  99   // store the current value of pan and tilt positions.
 100   int pan_;
 101   int tilt_;
 102
 103   base::WeakPtrFactory<ViscaWebcam> weak_ptr_factory_;
 104
 105   DISALLOW_COPY_AND_ASSIGN(ViscaWebcam);
 106 };
 107
 108 }  // namespace extensions
 109
 110 #endif  // EXTENSIONS_BROWSER_API_WEBCAM_PRIVATE_VISCA_WEBCAM_H_