// This file is part of Moonfire NVR, a security camera digital video recorder.
// Copyright (C) 2016 Scott Lamb <slamb@slamb.org>
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// In addition, as a special exception, the copyright holders give
// permission to link the code of portions of this program with the
// OpenSSL library under certain conditions as described in each
// individual source file, and distribute linked combinations including
// the two.
//
// You must obey the GNU General Public License in all respects for all
// of the code used other than OpenSSL. If you modify file(s) with this
// exception, you may extend this exception to your version of the
// file(s), but you are not obligated to do so. If you do not wish to do
// so, delete this exception statement from your version. If you delete
// this exception statement from all source files in the program, then
// also delete it here.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
//
// moonfire-nvr-test.cc: tests of the moonfire-nvr.cc interface.

#include <gflags/gflags.h>
#include <gmock/gmock.h>
#include <gtest/gtest.h>

#include "moonfire-nvr.h"
#include "string.h"
#include "testutil.h"

DECLARE_bool(alsologtostderr);

using testing::_;
using testing::AnyNumber;
using testing::HasSubstr;
using testing::Invoke;
using testing::Return;

namespace moonfire_nvr {
namespace {

class MockVideoSource : public VideoSource {
 public:
  // Proxy, as gmock doesn't support non-copyable return values.
  std::unique_ptr<InputVideoPacketStream> OpenRtsp(
      const std::string &url, std::string *error_message) final {
    return std::unique_ptr<InputVideoPacketStream>(
        OpenRtspRaw(url, error_message));
  }
  std::unique_ptr<InputVideoPacketStream> OpenFile(
      const std::string &file, std::string *error_message) final {
    return std::unique_ptr<InputVideoPacketStream>(
        OpenFileRaw(file, error_message));
  }

  MOCK_METHOD2(OpenRtspRaw,
               InputVideoPacketStream *(const std::string &, std::string *));
  MOCK_METHOD2(OpenFileRaw,
               InputVideoPacketStream *(const std::string &, std::string *));
};

class FileManagerTest : public testing::Test {
 protected:
  FileManagerTest() {
    test_dir_ = PrepareTempDirOrDie("moonfire-nvr-file-manager");
  }

  std::vector<std::string> GetFilenames(const FileManager &mgr) {
    std::vector<std::string> out;
    mgr.ForEachFile([&out](const std::string &f, const struct stat &) {
      out.push_back(f);
    });
    return out;
  }

  std::string test_dir_;
};

TEST_F(FileManagerTest, InitWithNoDirectory) {
  std::string subdir = test_dir_ + "/" + "subdir";
  FileManager manager("foo", subdir, 0);

  // Should succeed.
  std::string error_message;
  EXPECT_TRUE(manager.Init(&error_message)) << error_message;

  // Should create the directory.
  struct stat buf;
  ASSERT_EQ(0, lstat(subdir.c_str(), &buf)) << strerror(errno);
  EXPECT_TRUE(S_ISDIR(buf.st_mode));

  // Should report empty.
  EXPECT_EQ(0, manager.total_bytes());
  EXPECT_THAT(GetFilenames(manager), testing::ElementsAre());

  // Adding files: nonexistent, simple, out of order.
  EXPECT_FALSE(manager.AddFile("nonexistent.mp4", &error_message));
  WriteFileOrDie(subdir + "/1.mp4", "1");
  WriteFileOrDie(subdir + "/2.mp4", "123");
  EXPECT_TRUE(manager.AddFile("2.mp4", &error_message)) << error_message;
  EXPECT_EQ(3, manager.total_bytes());
  EXPECT_THAT(GetFilenames(manager), testing::ElementsAre("2.mp4"));
  EXPECT_TRUE(manager.AddFile("1.mp4", &error_message)) << error_message;
  EXPECT_EQ(4, manager.total_bytes());
  EXPECT_THAT(GetFilenames(manager), testing::ElementsAre("1.mp4", "2.mp4"));

  EXPECT_TRUE(manager.Rotate(&error_message)) << error_message;
  EXPECT_EQ(0, manager.total_bytes());
  EXPECT_THAT(GetFilenames(manager), testing::ElementsAre());
}

TEST_F(FileManagerTest, InitAndRotateWithExistingFiles) {
  WriteFileOrDie(test_dir_ + "/1.mp4", "1");
  WriteFileOrDie(test_dir_ + "/2.mp4", "123");
  WriteFileOrDie(test_dir_ + "/3.mp4", "12345");
  WriteFileOrDie(test_dir_ + "/other", "1234567");
  FileManager manager("foo", test_dir_, 8);

  // Should succeed.
  std::string error_message;
  EXPECT_TRUE(manager.Init(&error_message)) << error_message;

  EXPECT_THAT(GetFilenames(manager),
              testing::ElementsAre("1.mp4", "2.mp4", "3.mp4"));
  EXPECT_EQ(1 + 3 + 5, manager.total_bytes());

  EXPECT_TRUE(manager.Rotate(&error_message)) << error_message;
  EXPECT_THAT(GetFilenames(manager), testing::ElementsAre("2.mp4", "3.mp4"));
  EXPECT_EQ(8, manager.total_bytes());
}

class StreamTest : public testing::Test {
 public:
  StreamTest() {
    test_dir_ = PrepareTempDirOrDie("moonfire-nvr-stream-copier");
    env_.clock = &clock_;
    env_.video_source = &video_source_;
    clock_.Sleep({1430006400, 0});  // 2016-04-26 00:00:00 UTC

    config_.set_base_path(test_dir_);
    config_.set_rotate_sec(5);
    auto *camera = config_.add_camera();
    camera->set_short_name("test");
    camera->set_host("test-camera");
    camera->set_user("foo");
    camera->set_password("bar");
    camera->set_main_rtsp_path("/main");
    camera->set_sub_rtsp_path("/sub");
    camera->set_retain_bytes(1000000);
  }

  // A function to use in OpenRtspRaw invocations which shuts down the stream
  // and indicates that the input video source can't be opened.
  InputVideoPacketStream *Shutdown(const std::string &url,
                                   std::string *error_message) {
    *error_message = "(shutting down)";
    signal_.Shutdown();
    return nullptr;
  }

  struct Frame {
    Frame(bool is_key, int64_t pts, int64_t duration)
        : is_key(is_key), pts(pts), duration(duration) {}
    bool is_key;
    int64_t pts;
    int64_t duration;

    bool operator==(const Frame &o) const {
      return is_key == o.is_key && pts == o.pts && duration == o.duration;
    }

    friend std::ostream &operator<<(std::ostream &os, const Frame &f) {
      return os << "Frame(" << f.is_key << ", " << f.pts << ", " << f.duration
                << ")";
    }
  };

  std::vector<Frame> GetFrames(const std::string &path) {
    std::vector<Frame> frames;
    std::string error_message;
    std::string full_path = StrCat(test_dir_, "/test/", path);
    auto f = GetRealVideoSource()->OpenFile(full_path, &error_message);
    if (f == nullptr) {
      ADD_FAILURE() << full_path << ": " << error_message;
      return frames;
    }
    VideoPacket pkt;
    while (f->GetNext(&pkt, &error_message)) {
      frames.push_back(Frame(pkt.is_key(), pkt.pts(), pkt.pkt()->duration));
    }
    EXPECT_EQ("", error_message);
    return frames;
  }

  ShutdownSignal signal_;
  Config config_;
  SimulatedClock clock_;
  testing::StrictMock<MockVideoSource> video_source_;
  Environment env_;
  std::string test_dir_;
};

class ProxyingInputVideoPacketStream : public InputVideoPacketStream {
 public:
  explicit ProxyingInputVideoPacketStream(
      std::unique_ptr<InputVideoPacketStream> base, SimulatedClock *clock)
      : base_(std::move(base)), clock_(clock) {}

  bool GetNext(VideoPacket *pkt, std::string *error_message) final {
    if (pkts_left_-- == 0) {
      *error_message = "(pkt limit reached)";
      return false;
    }

    // Advance time to when this packet starts.
    clock_->Sleep(SecToTimespec(last_duration_sec_));
    if (!base_->GetNext(pkt, error_message)) {
      return false;
    }
    last_duration_sec_ =
        pkt->pkt()->duration * av_q2d(base_->stream()->time_base);

    // Adjust timestamps.
    if (ts_offset_pkts_left_ > 0) {
      pkt->pkt()->pts += ts_offset_;
      pkt->pkt()->dts += ts_offset_;
      --ts_offset_pkts_left_;
    }

    // Use a fixed duration, as the duration from a real RTSP stream is only
    // an estimate. Our test video is 1 fps, 90 kHz time base.
    pkt->pkt()->duration = 90000;

    return true;
  }

  const AVStream *stream() const final { return base_->stream(); }

  void set_ts_offset(int64_t offset, int pkts) {
    ts_offset_ = offset;
    ts_offset_pkts_left_ = pkts;
  }

  void set_pkts(int num) { pkts_left_ = num; }

 private:
  std::unique_ptr<InputVideoPacketStream> base_;
  SimulatedClock *clock_ = nullptr;
  double last_duration_sec_ = 0.;
  int64_t ts_offset_ = 0;
  int ts_offset_pkts_left_ = 0;
  int pkts_left_ = std::numeric_limits<int>::max();
};

TEST_F(StreamTest, Basic) {
  Stream stream(&signal_, config_, &env_, config_.camera(0));
  std::string error_message;
  ASSERT_TRUE(stream.Init(&error_message)) << error_message;

  // This is a ~1 fps test video with a timebase of 90 kHz.
  auto in_stream = GetRealVideoSource()->OpenFile("../src/testdata/clip.mp4",
                                                  &error_message);
  ASSERT_TRUE(in_stream != nullptr) << error_message;
  auto *proxy_stream =
      new ProxyingInputVideoPacketStream(std::move(in_stream), &clock_);

  // The starting pts of the input should be irrelevant.
  proxy_stream->set_ts_offset(180000, std::numeric_limits<int>::max());

  EXPECT_CALL(video_source_, OpenRtspRaw("rtsp://foo:bar@test-camera/main", _))
      .WillOnce(Return(proxy_stream))
      .WillOnce(Invoke(this, &StreamTest::Shutdown));
  stream.Run();

  // Compare frame-by-frame.
  // Note below that while the rotation is scheduled to happen near 5-second
  // boundaries (such as 2016-04-26 00:00:05), it gets deferred until the next
  // key frame, which in this case is 00:00:07.
  EXPECT_THAT(stream.GetFilesForTesting(),
              testing::ElementsAre("20150426000000_test.mp4",
                                   "20150426000007_test.mp4"));
  EXPECT_THAT(GetFrames("20150426000000_test.mp4"),
              testing::ElementsAre(
                  Frame(true, 0, 90379), Frame(false, 90379, 89884),
                  Frame(false, 180263, 89749), Frame(false, 270012, 89981),
                  Frame(true, 359993, 90055),
                  Frame(false, 450048,
                        89967),  // pts_time 5.000533, past rotation time.
                  Frame(false, 540015, 90021),
                  Frame(false, 630036,
                        90000)));  // XXX: duration=89958 would be better!
  EXPECT_THAT(
      GetFrames("20150426000007_test.mp4"),
      testing::ElementsAre(Frame(true, 0, 90011), Frame(false, 90011, 90000)));
  // Note that the final "90000" duration is ffmpeg's estimate based on frame
  // rate. For non-final packets, the correct duration gets written based on
  // the next packet's timestamp. The same currently applies to the first
  // written segment---it uses an estimated time, not the real time until the
  // next packet. This probably should be fixed...
}

TEST_F(StreamTest, NonIncreasingTimestamp) {
  Stream stream(&signal_, config_, &env_, config_.camera(0));
  std::string error_message;
  ASSERT_TRUE(stream.Init(&error_message)) << error_message;
  auto in_stream = GetRealVideoSource()->OpenFile("../src/testdata/clip.mp4",
                                                  &error_message);
  ASSERT_TRUE(in_stream != nullptr) << error_message;
  auto *proxy_stream =
      new ProxyingInputVideoPacketStream(std::move(in_stream), &clock_);
  proxy_stream->set_ts_offset(12345678, 1);
  EXPECT_CALL(video_source_, OpenRtspRaw("rtsp://foo:bar@test-camera/main", _))
      .WillOnce(Return(proxy_stream))
      .WillOnce(Invoke(this, &StreamTest::Shutdown));

  {
    ScopedMockLog log;
    EXPECT_CALL(log, Log(_, _, _)).Times(AnyNumber());
    EXPECT_CALL(log,
                Log(_, _, HasSubstr("Rejecting non-increasing pts=90379")));
    log.Start();
    stream.Run();
  }

  // The output file should still be added to the file manager, with the one
  // packet that made it.
  EXPECT_THAT(stream.GetFilesForTesting(),
              testing::ElementsAre("20150426000000_test.mp4"));
  EXPECT_THAT(
      GetFrames("20150426000000_test.mp4"),
      testing::ElementsAre(Frame(true, 0, 90000)));  // estimated duration.
}

TEST_F(StreamTest, RetryOnInputError) {
  Stream stream(&signal_, config_, &env_, config_.camera(0));
  std::string error_message;
  ASSERT_TRUE(stream.Init(&error_message)) << error_message;

  auto in_stream_1 = GetRealVideoSource()->OpenFile("../src/testdata/clip.mp4",
                                                    &error_message);
  ASSERT_TRUE(in_stream_1 != nullptr) << error_message;
  auto *proxy_stream_1 =
      new ProxyingInputVideoPacketStream(std::move(in_stream_1), &clock_);
  proxy_stream_1->set_pkts(1);

  auto in_stream_2 = GetRealVideoSource()->OpenFile("../src/testdata/clip.mp4",
                                                    &error_message);
  ASSERT_TRUE(in_stream_2 != nullptr) << error_message;
  auto *proxy_stream_2 =
      new ProxyingInputVideoPacketStream(std::move(in_stream_2), &clock_);
  proxy_stream_2->set_pkts(1);

  EXPECT_CALL(video_source_, OpenRtspRaw("rtsp://foo:bar@test-camera/main", _))
      .WillOnce(Return(proxy_stream_1))
      .WillOnce(Return(proxy_stream_2))
      .WillOnce(Invoke(this, &StreamTest::Shutdown));
  stream.Run();

  // Each attempt should have resulted in a file with one packet.
  EXPECT_THAT(stream.GetFilesForTesting(),
              testing::ElementsAre("20150426000000_test.mp4",
                                   "20150426000001_test.mp4"));
  EXPECT_THAT(GetFrames("20150426000000_test.mp4"),
              testing::ElementsAre(Frame(true, 0, 90000)));
  EXPECT_THAT(GetFrames("20150426000001_test.mp4"),
              testing::ElementsAre(Frame(true, 0, 90000)));
}

TEST_F(StreamTest, DiscardInitialNonKeyFrames) {
  Stream stream(&signal_, config_, &env_, config_.camera(0));
  std::string error_message;
  ASSERT_TRUE(stream.Init(&error_message)) << error_message;
  auto in_stream = GetRealVideoSource()->OpenFile("../src/testdata/clip.mp4",
                                                  &error_message);
  ASSERT_TRUE(in_stream != nullptr) << error_message;

  // Discard the initial key frame packet.
  VideoPacket dummy;
  ASSERT_TRUE(in_stream->GetNext(&dummy, &error_message)) << error_message;

  auto *proxy_stream =
      new ProxyingInputVideoPacketStream(std::move(in_stream), &clock_);
  EXPECT_CALL(video_source_, OpenRtspRaw("rtsp://foo:bar@test-camera/main", _))
      .WillOnce(Return(proxy_stream))
      .WillOnce(Invoke(this, &StreamTest::Shutdown));
  stream.Run();

  // Skipped: initial key frame packet (duration 90379)
  // Ignored: duration 89884, 89749, 89981 (total pts time: 2.99571... sec)
  // Thus, the first output file should start at 00:00:02.
  EXPECT_THAT(stream.GetFilesForTesting(),
              testing::ElementsAre("20150426000002_test.mp4",
                                   "20150426000006_test.mp4"));
  EXPECT_THAT(
      GetFrames("20150426000002_test.mp4"),
      testing::ElementsAre(
          Frame(true, 0, 90055),
          Frame(false, 90055, 89967),  // pts_time 5.000533, past rotation time.
          Frame(false, 180022, 90021),
          Frame(false, 270043,
                90000)));  // XXX: duration=89958 would be better!
  EXPECT_THAT(
      GetFrames("20150426000006_test.mp4"),
      testing::ElementsAre(Frame(true, 0, 90011), Frame(false, 90011, 90000)));
}

// TODO: test output stream error (on open, writing packet, closing).

}  // namespace
}  // namespace moonfire_nvr

int main(int argc, char **argv) {
  FLAGS_alsologtostderr = true;
  google::ParseCommandLineFlags(&argc, &argv, true);
  testing::InitGoogleTest(&argc, argv);
  google::InitGoogleLogging(argv[0]);
  return RUN_ALL_TESTS();
}