1// Copyright 2014 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 MEDIA_MIDI_USB_MIDI_INPUT_STREAM_H_
6#define MEDIA_MIDI_USB_MIDI_INPUT_STREAM_H_
7
8#include <map>
9#include <vector>
10
11#include "base/basictypes.h"
12#include "base/containers/hash_tables.h"
13#include "base/time/time.h"
14#include "media/base/media_export.h"
15#include "media/midi/usb_midi_jack.h"
16
17namespace media {
18
19class UsbMidiDevice;
20
21// UsbMidiInputStream converts USB-MIDI data to MIDI data.
22// See "USB Device Class Definition for MIDI Devices" Release 1.0,
23// Section 4 "USB-MIDI Event Packets" for details.
24class MEDIA_EXPORT UsbMidiInputStream {
25 public:
26  class MEDIA_EXPORT Delegate {
27   public:
28    virtual ~Delegate() {}
29    // This function is called when some data arrives to a USB-MIDI jack.
30    // An input USB-MIDI jack corresponds to an input MIDIPortInfo.
31    virtual void OnReceivedData(size_t jack_index,
32                                const uint8* data,
33                                size_t size,
34                                base::TimeTicks time) = 0;
35  };
36
37  // This is public for testing.
38  struct JackUniqueKey {
39    JackUniqueKey(UsbMidiDevice* device, int endpoint_number, int cable_number);
40    bool operator==(const JackUniqueKey& that) const;
41    bool operator<(const JackUniqueKey& that) const;
42
43    UsbMidiDevice* device;
44    int endpoint_number;
45    int cable_number;
46  };
47
48  UsbMidiInputStream(const std::vector<UsbMidiJack>& jacks,
49                     Delegate* delegate);
50  ~UsbMidiInputStream();
51
52  // This function should be called when some data arrives to a USB-MIDI
53  // endpoint. This function converts the data to MIDI data and call
54  // |delegate->OnReceivedData| with it.
55  // |size| must be a multiple of |kPacketSize|.
56  void OnReceivedData(UsbMidiDevice* device,
57                      int endpoint_number,
58                      const uint8* data,
59                      size_t size,
60                      base::TimeTicks time);
61
62  std::vector<JackUniqueKey> RegisteredJackKeysForTesting() const;
63
64 private:
65  static const size_t kPacketSize = 4;
66  // Processes a USB-MIDI Event Packet.
67  // The first |kPacketSize| bytes of |packet| must be accessible.
68  void ProcessOnePacket(UsbMidiDevice* device,
69                        int endpoint_number,
70                        const uint8* packet,
71                        base::TimeTicks time);
72
73  // A map from UsbMidiJack to its index in |jacks_|.
74  std::map<JackUniqueKey, size_t> jack_dictionary_;
75
76  // Not owned
77  Delegate* delegate_;
78
79  DISALLOW_COPY_AND_ASSIGN(UsbMidiInputStream);
80};
81
82}  // namespace media
83
84#endif  // MEDIA_MIDI_USB_MIDI_INPUT_STREAM_H_
85