[Cast] Refactor/clean-up VideoReceiver to match AudioReceiver as closely as possible.

media/cast/video_receiver/video_receiver_unittest.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include <stdint.h>
-
 #include "base/bind.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/test/simple_test_tick_clock.h"
 #include "media/cast/cast_defines.h"
 #include "media/cast/cast_environment.h"
 #include "media/cast/logging/simple_event_subscriber.h"
 #include "media/cast/test/fake_single_thread_task_runner.h"
 #include "media/cast/transport/pacing/mock_paced_packet_sender.h"
 #include "media/cast/video_receiver/video_receiver.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
-static const int kPacketSize = 1500;
-static const int64 kStartMillisecond = INT64_C(12345678900000);
-
 namespace media {
 namespace cast {
 
-using testing::_;
+using ::testing::_;
 
 namespace {
-// Was thread counted thread safe.
-class TestVideoReceiverCallback
-    : public base::RefCountedThreadSafe<TestVideoReceiverCallback> {
+
+const int kPacketSize = 1500;
+const int64 kStartMillisecond = INT64_C(12345678900000);
+const uint32 kFirstFrameId = 1234;
+
+class FakeVideoClient {
  public:
-  TestVideoReceiverCallback() : num_called_(0) {}
+  FakeVideoClient() : num_called_(0) {}
+  virtual ~FakeVideoClient() {}
 
-  // TODO(mikhal): Set and check expectations.
-  void DecodeComplete(const scoped_refptr<media::VideoFrame>& video_frame,
-                      const base::TimeTicks& render_time) {
-    ++num_called_;
+  void SetNextExpectedResult(uint32 expected_frame_id,
+                             const base::TimeTicks& expected_playout_time) {
+    expected_frame_id_ = expected_frame_id;
+    expected_playout_time_ = expected_playout_time;
   }
 
-  void FrameToDecode(scoped_ptr<transport::EncodedVideoFrame> video_frame,
-                     const base::TimeTicks& render_time) {
-    EXPECT_TRUE(video_frame->key_frame);
+  void DeliverEncodedVideoFrame(
+      scoped_ptr<transport::EncodedVideoFrame> video_frame,
+      const base::TimeTicks& playout_time) {
+    ASSERT_FALSE(!video_frame)
+        << "If at shutdown: There were unsatisfied requests enqueued.";
+    EXPECT_EQ(expected_frame_id_, video_frame->frame_id);
     EXPECT_EQ(transport::kVp8, video_frame->codec);
+    EXPECT_EQ(expected_playout_time_, playout_time);
     ++num_called_;
   }
 
   int number_times_called() const { return num_called_; }
 
- protected:
-  virtual ~TestVideoReceiverCallback() {}
+ private:
+  int num_called_;
+  uint32 expected_frame_id_;
+  base::TimeTicks expected_playout_time_;
 
- private:
-  friend class base::RefCountedThreadSafe<TestVideoReceiverCallback>;
-
-  int num_called_;
-
-  DISALLOW_COPY_AND_ASSIGN(TestVideoReceiverCallback);
+  DISALLOW_COPY_AND_ASSIGN(FakeVideoClient);
 };
 }  // namespace
 
 class VideoReceiverTest : public ::testing::Test {
  protected:
   VideoReceiverTest() {
     // Configure to use vp8 software implementation.
+    config_.rtp_max_delay_ms = 100;
+    config_.use_external_decoder = false;
+    // Note: Frame rate must divide 1000 without remainder so the test code
+    // doesn't have to account for rounding errors.
+    config_.max_frame_rate = 25;
     config_.codec = transport::kVp8;
-    config_.use_external_decoder = false;
     testing_clock_ = new base::SimpleTestTickClock();
+    testing_clock_->Advance(
+        base::TimeDelta::FromMilliseconds(kStartMillisecond));
     task_runner_ = new test::FakeSingleThreadTaskRunner(testing_clock_);
+
     cast_environment_ =
         new CastEnvironment(scoped_ptr<base::TickClock>(testing_clock_).Pass(),
                             task_runner_,
                             task_runner_,
                             task_runner_);
+
     receiver_.reset(new VideoReceiver(
-        cast_environment_, config_, &mock_transport_, target_delay_cb_));
-    testing_clock_->Advance(
-        base::TimeDelta::FromMilliseconds(kStartMillisecond));
-    video_receiver_callback_ = new TestVideoReceiverCallback();
+        cast_environment_, config_, &mock_transport_));
+  }
 
+  virtual ~VideoReceiverTest() {}
+
+  virtual void SetUp() {
     payload_.assign(kPacketSize, 0);
 
     // Always start with a key frame.
     rtp_header_.is_key_frame = true;
-    rtp_header_.frame_id = 1234;
+    rtp_header_.frame_id = kFirstFrameId;
     rtp_header_.packet_id = 0;
     rtp_header_.max_packet_id = 0;
     rtp_header_.is_reference = false;
     rtp_header_.reference_frame_id = 0;
-    rtp_header_.webrtc.header.timestamp = 9000;
+    rtp_header_.webrtc.header.timestamp = 0;
   }
 
-  virtual ~VideoReceiverTest() {}
+  void FeedOneFrameIntoReceiver() {
+    receiver_->OnReceivedPayloadData(
+        payload_.data(), payload_.size(), rtp_header_);
+  }
 
-  transport::MockPacedPacketSender mock_transport_;
   VideoReceiverConfig config_;
-  scoped_ptr<VideoReceiver> receiver_;
   std::vector<uint8> payload_;
   RtpCastHeader rtp_header_;
   base::SimpleTestTickClock* testing_clock_;  // Owned by CastEnvironment.
-
+  transport::MockPacedPacketSender mock_transport_;
   scoped_refptr<test::FakeSingleThreadTaskRunner> task_runner_;
   scoped_refptr<CastEnvironment> cast_environment_;
-  scoped_refptr<TestVideoReceiverCallback> video_receiver_callback_;
-  SetTargetDelayCallback target_delay_cb_;
+  FakeVideoClient fake_video_client_;
+
+  // Important for the VideoReceiver to be declared last, since its dependencies
+  // must remain alive until after its destruction.
+  scoped_ptr<VideoReceiver> receiver_;
 
   DISALLOW_COPY_AND_ASSIGN(VideoReceiverTest);
 };
 
-TEST_F(VideoReceiverTest, GetOnePacketEncodedframe) {
-  EXPECT_CALL(mock_transport_, SendRtcpPacket(_))
-      .WillRepeatedly(testing::Return(true));
-  receiver_->OnReceivedPayloadData(
-      payload_.data(), payload_.size(), rtp_header_);
-
-  VideoFrameEncodedCallback frame_to_decode_callback = base::Bind(
-      &TestVideoReceiverCallback::FrameToDecode, video_receiver_callback_);
-
-  receiver_->GetEncodedVideoFrame(frame_to_decode_callback);
-  task_runner_->RunTasks();
-  EXPECT_EQ(video_receiver_callback_->number_times_called(), 1);
-}
-
-TEST_F(VideoReceiverTest, MultiplePackets) {
+TEST_F(VideoReceiverTest, GetOnePacketEncodedFrame) {
   SimpleEventSubscriber event_subscriber;
   cast_environment_->Logging()->AddRawEventSubscriber(&event_subscriber);
 
   EXPECT_CALL(mock_transport_, SendRtcpPacket(_))
       .WillRepeatedly(testing::Return(true));
-  rtp_header_.max_packet_id = 2;
-  receiver_->OnReceivedPayloadData(
-      payload_.data(), payload_.size(), rtp_header_);
-  ++rtp_header_.packet_id;
-  ++rtp_header_.webrtc.header.sequenceNumber;
-  receiver_->OnReceivedPayloadData(
-      payload_.data(), payload_.size(), rtp_header_);
-  ++rtp_header_.packet_id;
-  receiver_->OnReceivedPayloadData(
-      payload_.data(), payload_.size(), rtp_header_);
 
-  VideoFrameEncodedCallback frame_to_decode_callback = base::Bind(
-      &TestVideoReceiverCallback::FrameToDecode, video_receiver_callback_);
+  // Enqueue a request for a video frame.
+  receiver_->GetEncodedVideoFrame(
+      base::Bind(&FakeVideoClient::DeliverEncodedVideoFrame,
+                 base::Unretained(&fake_video_client_)));
 
-  receiver_->GetEncodedVideoFrame(frame_to_decode_callback);
+  // The request should not be satisfied since no packets have been received.
+  task_runner_->RunTasks();
+  EXPECT_EQ(0, fake_video_client_.number_times_called());
 
+  // Deliver one video frame to the receiver and expect to get one frame back.
+  fake_video_client_.SetNextExpectedResult(kFirstFrameId,
+                                           testing_clock_->NowTicks());
+  FeedOneFrameIntoReceiver();
   task_runner_->RunTasks();
-  EXPECT_EQ(video_receiver_callback_->number_times_called(), 1);
+  EXPECT_EQ(1, fake_video_client_.number_times_called());
 
   std::vector<FrameEvent> frame_events;
   event_subscriber.GetFrameEventsAndReset(&frame_events);
 
   ASSERT_TRUE(!frame_events.empty());
   EXPECT_EQ(kVideoAckSent, frame_events.begin()->type);
   EXPECT_EQ(rtp_header_.frame_id, frame_events.begin()->frame_id);
   EXPECT_EQ(rtp_header_.webrtc.header.timestamp,
             frame_events.begin()->rtp_timestamp);
+
   cast_environment_->Logging()->RemoveRawEventSubscriber(&event_subscriber);
 }
 
-TEST_F(VideoReceiverTest, GetOnePacketRawframe) {
+TEST_F(VideoReceiverTest, MultiplePendingGetCalls) {
   EXPECT_CALL(mock_transport_, SendRtcpPacket(_))
       .WillRepeatedly(testing::Return(true));
-  receiver_->OnReceivedPayloadData(
-      payload_.data(), payload_.size(), rtp_header_);
-  // Decode error - requires legal input.
-  VideoFrameDecodedCallback frame_decoded_callback = base::Bind(
-      &TestVideoReceiverCallback::DecodeComplete, video_receiver_callback_);
-  receiver_->GetRawVideoFrame(frame_decoded_callback);
+
+  // Enqueue a request for an video frame.
+  const VideoFrameEncodedCallback frame_encoded_callback =
+      base::Bind(&FakeVideoClient::DeliverEncodedVideoFrame,
+                 base::Unretained(&fake_video_client_));
+  receiver_->GetEncodedVideoFrame(frame_encoded_callback);
   task_runner_->RunTasks();
-  EXPECT_EQ(video_receiver_callback_->number_times_called(), 0);
+  EXPECT_EQ(0, fake_video_client_.number_times_called());
+
+  // Receive one video frame and expect to see the first request satisfied.
+  fake_video_client_.SetNextExpectedResult(kFirstFrameId,
+                                           testing_clock_->NowTicks());
+  const base::TimeTicks time_at_first_frame_feed = testing_clock_->NowTicks();
+  FeedOneFrameIntoReceiver();
+  task_runner_->RunTasks();
+  EXPECT_EQ(1, fake_video_client_.number_times_called());
+
+  testing_clock_->Advance(
+      base::TimeDelta::FromSeconds(1) / config_.max_frame_rate);
+
+  // Enqueue a second request for an video frame, but it should not be
+  // fulfilled yet.
+  receiver_->GetEncodedVideoFrame(frame_encoded_callback);
+  task_runner_->RunTasks();
+  EXPECT_EQ(1, fake_video_client_.number_times_called());
+
+  // Receive one video frame out-of-order: Make sure that we are not continuous
+  // and that the RTP timestamp represents a time in the future.
+  rtp_header_.is_key_frame = false;
+  rtp_header_.frame_id = kFirstFrameId + 2;
+  rtp_header_.is_reference = true;
+  rtp_header_.reference_frame_id = 0;
+  rtp_header_.webrtc.header.timestamp +=
+      config_.rtp_max_delay_ms * kVideoFrequency / 1000;
+  fake_video_client_.SetNextExpectedResult(
+      kFirstFrameId + 2,
+      time_at_first_frame_feed +
+          base::TimeDelta::FromMilliseconds(config_.rtp_max_delay_ms));
+  FeedOneFrameIntoReceiver();
+
+  // Frame 2 should not come out at this point in time.
+  task_runner_->RunTasks();
+  EXPECT_EQ(1, fake_video_client_.number_times_called());
+
+  // Enqueue a third request for an video frame.
+  receiver_->GetEncodedVideoFrame(frame_encoded_callback);
+  task_runner_->RunTasks();
+  EXPECT_EQ(1, fake_video_client_.number_times_called());
+
+  // After |rtp_max_delay_ms| has elapsed, Frame 2 is emitted (to satisfy the
+  // second request) because a decision was made to skip over the no-show Frame
+  // 1.
+  testing_clock_->Advance(
+      base::TimeDelta::FromMilliseconds(config_.rtp_max_delay_ms));
+  task_runner_->RunTasks();
+  EXPECT_EQ(2, fake_video_client_.number_times_called());
+
+  // Receive Frame 3 and expect it to fulfill the third request immediately.
+  rtp_header_.frame_id = kFirstFrameId + 3;
+  rtp_header_.is_reference = false;
+  rtp_header_.reference_frame_id = 0;
+  rtp_header_.webrtc.header.timestamp +=
+      kVideoFrequency / config_.max_frame_rate;
+  fake_video_client_.SetNextExpectedResult(kFirstFrameId + 3,
+                                           testing_clock_->NowTicks());
+  FeedOneFrameIntoReceiver();
+  task_runner_->RunTasks();
+  EXPECT_EQ(3, fake_video_client_.number_times_called());
+
+  // Move forward another |rtp_max_delay_ms| and run any pending tasks (there
+  // should be none).  Expect no additional frames where emitted.
+  testing_clock_->Advance(
+      base::TimeDelta::FromMilliseconds(config_.rtp_max_delay_ms));
+  task_runner_->RunTasks();
+  EXPECT_EQ(3, fake_video_client_.number_times_called());
 }
 
-// TODO(pwestin): add encoded frames.
-
 }  // namespace cast
 }  // namespace media