// Copyright 2014 Google Inc. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd

#include "base/file_util.h"
#include "base/logging.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/stringprintf.h"
#include "mpd/base/mpd_builder.h"
#include "mpd/base/mpd_utils.h"
#include "mpd/test/mpd_builder_test_helper.h"
#include "mpd/test/xml_compare.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "third_party/libxml/src/include/libxml/xmlstring.h"

namespace dash_packager {

namespace {
// Get 'id' attribute from |node|, convert it to std::string and convert it to a
// number.
void ExpectXmlElementIdEqual(xmlNodePtr node, uint32 id) {
  const char kId[] = "id";
  xml::ScopedXmlPtr<xmlChar>::type id_attribute_xml_str(
      xmlGetProp(node, BAD_CAST kId));
  ASSERT_TRUE(id_attribute_xml_str);

  unsigned id_attribute_unsigned = 0;
  std::string id_attribute_str =
      reinterpret_cast<const char*>(id_attribute_xml_str.get());
  ASSERT_TRUE(base::StringToUint(id_attribute_str, &id_attribute_unsigned));

  ASSERT_EQ(id, id_attribute_unsigned);
}

// Using template to support both AdaptationSet and Representation.
template <typename T>
void CheckIdEqual(uint32 expected_id, T* node) {
  ASSERT_EQ(expected_id, node->id());

  // Also check if the XML generated by libxml2 has the correct id attribute.
  xml::ScopedXmlPtr<xmlNode>::type node_xml(node->GetXml());
  ASSERT_NO_FATAL_FAILURE(ExpectXmlElementIdEqual(node_xml.get(), expected_id));
}
}  // namespace

template <MpdBuilder::MpdType type>
class MpdBuilderTest: public ::testing::Test {
 public:
  MpdBuilderTest() : mpd_(type, MpdOptions()), representation_() {}
  virtual ~MpdBuilderTest() {}

  void CheckMpd(const std::string& expected_output_file) {
    std::string mpd_doc;
    ASSERT_TRUE(mpd_.ToString(&mpd_doc));
    ASSERT_TRUE(ValidateMpdSchema(mpd_doc));

    ASSERT_NO_FATAL_FAILURE(
        ExpectMpdToEqualExpectedOutputFile(mpd_doc, expected_output_file));
  }

 protected:
  void AddRepresentation(const MediaInfo& media_info) {
    AdaptationSet* adaptation_set = mpd_.AddAdaptationSet();
    ASSERT_TRUE(adaptation_set);

    Representation* representation =
        adaptation_set->AddRepresentation(media_info);
    ASSERT_TRUE(representation);

    representation_ = representation;
  }

  MpdBuilder mpd_;

  // We usually need only one representation.
  Representation* representation_;  // Owned by |mpd_|.

 private:
  DISALLOW_COPY_AND_ASSIGN(MpdBuilderTest);
};

class StaticMpdBuilderTest : public MpdBuilderTest<MpdBuilder::kStatic> {};

class DynamicMpdBuilderTest : public MpdBuilderTest<MpdBuilder::kDynamic> {
 public:
  virtual ~DynamicMpdBuilderTest() {}

  // Anchors availabilityStartTime so that the test result doesn't depend on the
  // current time.
  virtual void SetUp() {
    mpd_.options_.availability_start_time = "2011-12-25T12:30:00";
  }

  std::string GetDefaultMediaInfo() {
    const char kMediaInfo[] =
        "video_info {\n"
        "  codec: \"avc1.010101\"\n"
        "  width: 720\n"
        "  height: 480\n"
        "  time_scale: 10\n"
        "}\n"
        "reference_time_scale: %lu\n"
        "container_type: 1\n"
        "init_segment_name: \"init.mp4\"\n"
        "segment_template: \"$Time$.mp4\"\n";

    return base::StringPrintf(kMediaInfo, DefaultTimeScale());
  }

  uint64 DefaultTimeScale() const { return 1000; };
};

class SegmentTemplateTest : public DynamicMpdBuilderTest {
 public:
  SegmentTemplateTest()
      : bandwidth_estimator_(BandwidthEstimator::kUseAllBlocks) {}
  virtual ~SegmentTemplateTest() {}

  virtual void SetUp() {
    DynamicMpdBuilderTest::SetUp();
    ASSERT_NO_FATAL_FAILURE(AddRepresentationWithDefaultMediaInfo());
  }

  void AddSegments(uint64 start_time,
                   uint64 duration,
                   uint64 size,
                   uint64 repeat) {
    DCHECK(representation_);
    const char kSElementTemplate[] = "<S t=\"%lu\" d=\"%lu\" r=\"%lu\"/>\n";
    const char kSElementTemplateWithoutR[] = "<S t=\"%lu\" d=\"%lu\"/>\n";

    SegmentInfo s = {start_time, duration, repeat};
    segment_infos_for_expected_out_.push_back(s);
    if (repeat == 0) {
      expected_s_elements_ +=
          base::StringPrintf(kSElementTemplateWithoutR, start_time, duration);
    } else {
      expected_s_elements_ +=
          base::StringPrintf(kSElementTemplate, start_time, duration, repeat);
    }

    for (uint64 i = 0; i < repeat + 1; ++i) {
      representation_->AddNewSegment(start_time, duration, size);
      start_time += duration;
      bandwidth_estimator_.AddBlock(
          size, static_cast<double>(duration) / DefaultTimeScale());
    }
  }

 protected:
  void AddRepresentationWithDefaultMediaInfo() {
    ASSERT_NO_FATAL_FAILURE(
        AddRepresentation(ConvertToMediaInfo(GetDefaultMediaInfo())));
  }

  std::string TemplateOutputInsertSElementsAndBandwidth(
      const std::string& s_elements_string, uint64 bandwidth) {
    const char kOutputTemplate[] =
        "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
        "<MPD xmlns=\"urn:mpeg:DASH:schema:MPD:2011\" "
        "xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" "
        "xmlns:xlink=\"http://www.w3.org/1999/xlink\" "
        "xsi:schemaLocation=\"urn:mpeg:DASH:schema:MPD:2011 DASH-MPD.xsd\" "
        "availabilityStartTime=\"2011-12-25T12:30:00\" minBufferTime=\"PT2S\" "
        "type=\"dynamic\" profiles=\"urn:mpeg:dash:profile:isoff-live:2011\">\n"
        "  <Period start=\"PT0S\">\n"
        "    <AdaptationSet id=\"0\">\n"
        "      <Representation id=\"0\" bandwidth=\"%lu\" "
        "codecs=\"avc1.010101\" mimeType=\"video/mp4\" width=\"720\" "
        "height=\"480\">\n"
        "        <SegmentTemplate timescale=\"1000\" "
        "initialization=\"init.mp4\" media=\"$Time$.mp4\">\n"
        "          <SegmentTimeline>\n%s"
        "          </SegmentTimeline>\n"
        "        </SegmentTemplate>\n"
        "      </Representation>\n"
        "    </AdaptationSet>\n"
        "  </Period>\n"
        "</MPD>\n";

    return base::StringPrintf(
        kOutputTemplate, bandwidth, s_elements_string.data());
  }

  void CheckMpdAgainstExpectedResult() {
    std::string mpd_doc;
    ASSERT_TRUE(mpd_.ToString(&mpd_doc));
    ASSERT_TRUE(ValidateMpdSchema(mpd_doc));
    const std::string& expected_output =
        TemplateOutputInsertSElementsAndBandwidth(
            expected_s_elements_, bandwidth_estimator_.Estimate());
    ASSERT_TRUE(XmlEqual(expected_output, mpd_doc));
  }

 private:
  std::list<SegmentInfo> segment_infos_for_expected_out_;
  std::string expected_s_elements_;
  BandwidthEstimator bandwidth_estimator_;
};

TEST_F(StaticMpdBuilderTest, CheckAdaptationSetId) {
  base::AtomicSequenceNumber sequence_counter;
  const uint32 kAdaptationSetId = 42;

  AdaptationSet adaptation_set(kAdaptationSetId, &sequence_counter);
  ASSERT_NO_FATAL_FAILURE(CheckIdEqual(kAdaptationSetId, &adaptation_set));
}

TEST_F(StaticMpdBuilderTest, CheckRepresentationId) {
  const MediaInfo video_media_info = GetTestMediaInfo(kFileNameVideoMediaInfo1);
  const uint32 kRepresentationId = 1;

  Representation representation(video_media_info, kRepresentationId);
  EXPECT_TRUE(representation.Init());
  ASSERT_NO_FATAL_FAILURE(CheckIdEqual(kRepresentationId, &representation));
}

// Add one video check the output.
TEST_F(StaticMpdBuilderTest, Video) {
  MediaInfo video_media_info = GetTestMediaInfo(kFileNameVideoMediaInfo1);
  ASSERT_NO_FATAL_FAILURE(AddRepresentation(video_media_info));
  EXPECT_NO_FATAL_FAILURE(CheckMpd(kFileNameExpectedMpdOutputVideo1));
}

// Add both video and audio and check the output.
TEST_F(StaticMpdBuilderTest, VideoAndAudio) {
  MediaInfo video_media_info = GetTestMediaInfo(kFileNameVideoMediaInfo1);
  MediaInfo audio_media_info = GetTestMediaInfo(kFileNameAudioMediaInfo1);

  // The order matters here to check against expected output.
  AdaptationSet* video_adaptation_set = mpd_.AddAdaptationSet();
  ASSERT_TRUE(video_adaptation_set);

  AdaptationSet* audio_adaptation_set = mpd_.AddAdaptationSet();
  ASSERT_TRUE(audio_adaptation_set);

  Representation* audio_representation =
      audio_adaptation_set->AddRepresentation(audio_media_info);
  ASSERT_TRUE(audio_representation);

  Representation* video_representation =
      video_adaptation_set->AddRepresentation(video_media_info);
  ASSERT_TRUE(video_representation);

  EXPECT_NO_FATAL_FAILURE(CheckMpd(kFileNameExpectedMpdOutputAudio1AndVideo1));
}

// MPD schema has strict ordering. AudioChannelConfiguration must appear before
// ContentProtection.
TEST_F(StaticMpdBuilderTest, AudioChannelConfigurationWithContentProtection) {
  MediaInfo encrypted_audio_media_info =
      GetTestMediaInfo(kFileNameEncytpedAudioMediaInfo);

  AdaptationSet* audio_adaptation_set = mpd_.AddAdaptationSet();
  ASSERT_TRUE(audio_adaptation_set);

  Representation* audio_representation =
      audio_adaptation_set->AddRepresentation(encrypted_audio_media_info);
  ASSERT_TRUE(audio_representation);

  EXPECT_NO_FATAL_FAILURE(CheckMpd(kFileNameExpectedMpdOutputEncryptedAudio));
}

// Static profile requires bandwidth to be set because it has no other way to
// get the bandwidth for the Representation.
TEST_F(StaticMpdBuilderTest, MediaInfoMissingBandwidth) {
  MediaInfo video_media_info = GetTestMediaInfo(kFileNameVideoMediaInfo1);
  video_media_info.clear_bandwidth();
  AddRepresentation(video_media_info);

  std::string mpd_doc;
  ASSERT_FALSE(mpd_.ToString(&mpd_doc));
}

// Check whether the attributes are set correctly for dynamic <MPD> element.
TEST_F(DynamicMpdBuilderTest, CheckMpdAttributes) {
  static const char kExpectedOutput[] =
      "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
      "<MPD xmlns=\"urn:mpeg:DASH:schema:MPD:2011\" "
      "xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" "
      "xmlns:xlink=\"http://www.w3.org/1999/xlink\" "
      "xsi:schemaLocation=\"urn:mpeg:DASH:schema:MPD:2011 "
      "DASH-MPD.xsd\" availabilityStartTime=\"2011-12-25T12:30:00\" "
      "minBufferTime=\"PT2S\" type=\"dynamic\" "
      "profiles=\"urn:mpeg:dash:profile:isoff-live:2011\">\n"
      "  <Period start=\"PT0S\"/>\n"
      "</MPD>\n";

  std::string mpd_doc;
  ASSERT_TRUE(mpd_.ToString(&mpd_doc));
  ASSERT_EQ(kExpectedOutput, mpd_doc);
}

// Estimate the bandwidth given the info from AddNewSegment().
TEST_F(SegmentTemplateTest, OneSegmentNormal) {
  const uint64 kStartTime = 0;
  const uint64 kDuration = 10;
  const uint64 kSize = 128;
  AddSegments(kStartTime, kDuration, kSize, 0);

  // TODO(rkuroiwa): Clean up the test/data directory. It's a mess.
  EXPECT_NO_FATAL_FAILURE(CheckMpd(kFileNameExpectedMpdOutputDynamicNormal));
}

TEST_F(SegmentTemplateTest, NormalRepeatedSegmentDuration) {
  const uint64 kSize = 256;
  uint64 start_time = 0;
  uint64 duration = 40000;
  uint64 repeat = 2;
  AddSegments(start_time, duration, kSize, repeat);

  start_time += duration * (repeat + 1);
  duration = 54321;
  repeat = 0;
  AddSegments(start_time, duration, kSize, repeat);

  start_time += duration * (repeat + 1);
  duration = 12345;
  repeat = 0;
  AddSegments(start_time, duration, kSize, repeat);

  ASSERT_NO_FATAL_FAILURE(CheckMpdAgainstExpectedResult());
}

TEST_F(SegmentTemplateTest, RepeatedSegmentsFromNonZeroStartTime) {
  const uint64 kSize = 100000;
  uint64 start_time = 0;
  uint64 duration = 100000;
  uint64 repeat = 2;
  AddSegments(start_time, duration, kSize, repeat);

  start_time += duration * (repeat + 1);
  duration = 20000;
  repeat = 3;
  AddSegments(start_time, duration, kSize, repeat);

  start_time += duration * (repeat + 1);
  duration = 32123;
  repeat = 3;
  AddSegments(start_time, duration, kSize, repeat);

  ASSERT_NO_FATAL_FAILURE(CheckMpdAgainstExpectedResult());
}

// Segments not starting from 0.
// Start time is 10. Make sure r gets set correctly.
TEST_F(SegmentTemplateTest, NonZeroStartTime) {
  const uint64 kStartTime = 10;
  const uint64 kDuration = 22000;
  const uint64 kSize = 123456;
  const uint64 kRepeat = 1;
  AddSegments(kStartTime, kDuration, kSize, kRepeat);

  ASSERT_NO_FATAL_FAILURE(CheckMpdAgainstExpectedResult());
}

// There is a gap in the segments, but still valid.
TEST_F(SegmentTemplateTest, NonContiguousLiveInfo) {
  const uint64 kStartTime = 10;
  const uint64 kDuration = 22000;
  const uint64 kSize = 123456;
  const uint64 kRepeat = 0;
  AddSegments(kStartTime, kDuration, kSize, kRepeat);

  const uint64 kStartTimeOffset = 100;
  AddSegments(kDuration + kStartTimeOffset, kDuration, kSize, kRepeat);

  ASSERT_NO_FATAL_FAILURE(CheckMpdAgainstExpectedResult());
}

// Add segments out of order. Segments that start before the previous segment
// cannot be added.
TEST_F(SegmentTemplateTest, OutOfOrder) {
  const uint64 kEarlierStartTime = 0;
  const uint64 kLaterStartTime = 1000;
  const uint64 kDuration = 1000;
  const uint64 kSize = 123456;
  const uint64 kRepeat = 0;

  AddSegments(kLaterStartTime, kDuration, kSize, kRepeat);
  EXPECT_DEBUG_DEATH(AddSegments(kEarlierStartTime, kDuration, kSize, kRepeat),
                     "");

  ASSERT_NO_FATAL_FAILURE(CheckMpdAgainstExpectedResult());
}

// No segments should be overlapping.
TEST_F(SegmentTemplateTest, OverlappingSegments) {
  const uint64 kEarlierStartTime = 0;
  const uint64 kDuration = 1000;
  const uint64 kSize = 123456;
  const uint64 kRepeat = 0;

  const uint64 kOverlappingSegmentStartTime = kDuration / 2;
  CHECK_GT(kDuration, kOverlappingSegmentStartTime);

  AddSegments(kEarlierStartTime, kDuration, kSize, kRepeat);
  EXPECT_DEBUG_DEATH(
      AddSegments(kOverlappingSegmentStartTime, kDuration, kSize, kRepeat), "");

  ASSERT_NO_FATAL_FAILURE(CheckMpdAgainstExpectedResult());
}

// Some segments can be overlapped due to rounding errors. As long as it falls
// in the range of rounding error defined inside MpdBuilder, the segment gets
// accepted.
TEST_F(SegmentTemplateTest, OverlappingSegmentsWithinErrorRange) {
  const uint64 kEarlierStartTime = 0;
  const uint64 kDuration = 1000;
  const uint64 kSize = 123456;
  const uint64 kRepeat = 0;

  const uint64 kOverlappingSegmentStartTime = kDuration - 1;
  CHECK_GT(kDuration, kOverlappingSegmentStartTime);

  AddSegments(kEarlierStartTime, kDuration, kSize, kRepeat);
  AddSegments(kOverlappingSegmentStartTime, kDuration, kSize, kRepeat);

  ASSERT_NO_FATAL_FAILURE(CheckMpdAgainstExpectedResult());
}

}  // namespace dash_packager