shaka-packager/packager/media/formats/webvtt/webvtt_parser_unittest.cc

// Copyright 2017 Google LLC. 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 <packager/media/formats/webvtt/webvtt_parser.h>

#include <functional>

#include <gtest/gtest.h>

#include <packager/media/base/stream_info.h>
#include <packager/media/base/text_sample.h>

namespace shaka {
namespace media {
namespace {

const uint32_t kStreamId = 0;
const int32_t kTimeScale = 1000;

const char* kNoId = "";

void ExpectNoStyle(const TextFragmentStyle& style) {
  EXPECT_FALSE(style.underline);
  EXPECT_FALSE(style.bold);
  EXPECT_FALSE(style.italic);
}

void ExpectPlainCueWithBody(const TextFragment& fragment,
                            const std::string& expected) {
  ExpectNoStyle(fragment.style);
  ASSERT_TRUE(fragment.body.empty());
  ASSERT_FALSE(fragment.newline);

  if (expected.empty()) {
    EXPECT_TRUE(fragment.sub_fragments.empty());
  } else {
    ASSERT_EQ(fragment.sub_fragments.size(), 1u);
    ExpectNoStyle(fragment.sub_fragments[0].style);
    EXPECT_EQ(fragment.sub_fragments[0].body, expected);
  }
}

}  // namespace

class WebVttParserTest : public testing::Test {
 protected:
  void SetUpAndInitialize() {
    parser_ = std::make_shared<WebVttParser>();
    parser_->Init(
        std::bind(&WebVttParserTest::InitCB, this, std::placeholders::_1),
        std::bind(&WebVttParserTest::NewMediaSampleCB, this,
                  std::placeholders::_1, std::placeholders::_2),
        std::bind(&WebVttParserTest::NewTextSampleCB, this,
                  std::placeholders::_1, std::placeholders::_2),
        nullptr);
  }

  void InitCB(const std::vector<std::shared_ptr<StreamInfo>>& streams) {
    streams_ = streams;
  }

  bool NewMediaSampleCB(uint32_t stream_id,
                        std::shared_ptr<MediaSample> sample) {
    ADD_FAILURE() << "Should not get media samples";
    return false;
  }

  bool NewTextSampleCB(uint32_t stream_id, std::shared_ptr<TextSample> sample) {
    EXPECT_EQ(stream_id, kStreamId);
    samples_.emplace_back(std::move(sample));
    return true;
  }

  std::shared_ptr<WebVttParser> parser_;
  std::vector<std::shared_ptr<StreamInfo>> streams_;
  std::vector<std::shared_ptr<TextSample>> samples_;
};

TEST_F(WebVttParserTest, FailToParseEmptyFile) {
  const uint8_t text[] = "";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_TRUE(streams_.empty());
  ASSERT_TRUE(samples_.empty());
}

TEST_F(WebVttParserTest, ParseOnlyHeader) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_TRUE(streams_.empty());
  ASSERT_TRUE(samples_.empty());
}

TEST_F(WebVttParserTest, ParseHeaderWithBOM) {
  const uint8_t text[] =
      "\xEF\xBB\xBFWEBVTT\n"
      "\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_TRUE(streams_.empty());
  ASSERT_TRUE(samples_.empty());
}

TEST_F(WebVttParserTest, ParseNoHeaderWithoutExiting) {
  // A proper WebVTT file should have the "WEBVTT" string header.
  // But UDP input (not file) may be ingested when the header already
  // passed, and it will not be repeated later.
  const uint8_t text[] =
      "00:00:01.000 --> 00:00:02.000\n"
      "\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));

  ASSERT_TRUE(streams_.empty());
  ASSERT_TRUE(samples_.empty());
}

TEST_F(WebVttParserTest, FailToParseHeaderNotOneLine) {
  const uint8_t text[] =
      "WEBVTT\n"
      "WEBVTT\n"
      "\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));

  ASSERT_TRUE(streams_.empty());
  ASSERT_TRUE(samples_.empty());
}

TEST_F(WebVttParserTest, SendsStreamInfo) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "00:00:00.000 --> 00:01:00.000\n"
      "Testing\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  EXPECT_EQ(streams_[0]->time_scale(), kTimeScale);
  EXPECT_EQ(streams_[0]->is_encrypted(), false);
  EXPECT_EQ(streams_[0]->codec(), kCodecWebVtt);
  EXPECT_EQ(streams_[0]->codec_string(), "wvtt");
}

TEST_F(WebVttParserTest, IgnoresZeroDurationCues) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "00:01:00.000 --> 00:01:00.000\n"
      "This subtitle would never show\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  ASSERT_TRUE(samples_.empty());
}

TEST_F(WebVttParserTest, ParseOneCue) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "00:01:00.000 --> 01:00:00.000\n"
      "subtitle\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  ASSERT_EQ(samples_.size(), 1u);
  EXPECT_EQ(samples_[0]->id(), kNoId);
  EXPECT_EQ(samples_[0]->start_time(), 60000u);
  EXPECT_EQ(samples_[0]->duration(), 3540000u);
  ExpectPlainCueWithBody(samples_[0]->body(), "subtitle");

  // No settings
  const auto& settings = samples_[0]->settings();
  EXPECT_FALSE(settings.line);
  EXPECT_FALSE(settings.position);
  EXPECT_FALSE(settings.width);
  EXPECT_FALSE(settings.height);
  EXPECT_EQ(settings.region, "");
  EXPECT_EQ(settings.writing_direction, WritingDirection::kHorizontal);
  EXPECT_EQ(settings.text_alignment, TextAlignment::kCenter);
}

TEST_F(WebVttParserTest, ParseOneCueWithoutNewLine) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "00:01:00.000 --> 01:00:00.000\n"
      "subtitle";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  ASSERT_EQ(samples_.size(), 1u);
  EXPECT_EQ(samples_[0]->id(), kNoId);
  EXPECT_EQ(samples_[0]->start_time(), 60000u);
  EXPECT_EQ(samples_[0]->duration(), 3540000u);
  ExpectPlainCueWithBody(samples_[0]->body(), "subtitle");

  // No settings
  const auto& settings = samples_[0]->settings();
  EXPECT_FALSE(settings.line);
  EXPECT_FALSE(settings.position);
  EXPECT_FALSE(settings.width);
  EXPECT_FALSE(settings.height);
  EXPECT_EQ(settings.region, "");
  EXPECT_EQ(settings.writing_direction, WritingDirection::kHorizontal);
  EXPECT_EQ(settings.text_alignment, TextAlignment::kCenter);
}

TEST_F(WebVttParserTest, ParseOneCueWithStyle) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "STYLE\n"
      "::cue { color:lime }\n"
      "\n"
      "REGION\n"
      "id:scroll\n"
      "scroll:up\n"
      "\n"
      "00:01:00.000 --> 01:00:00.000\n"
      "subtitle\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  ASSERT_EQ(samples_.size(), 1u);
  auto* stream = static_cast<const TextStreamInfo*>(streams_[0].get());

  EXPECT_EQ(stream->css_styles(), "::cue { color:lime }");
  EXPECT_EQ(samples_[0]->id(), kNoId);
  EXPECT_EQ(samples_[0]->start_time(), 60000u);
  EXPECT_EQ(samples_[0]->duration(), 3540000u);
  ExpectPlainCueWithBody(samples_[0]->body(), "subtitle");
}

TEST_F(WebVttParserTest, ParseOneEmptyCue) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "00:01:00.000 --> 01:00:00.000\n"
      "\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  ASSERT_EQ(samples_.size(), 1u);
  ExpectPlainCueWithBody(samples_[0]->body(), "");
}

TEST_F(WebVttParserTest, FailToParseCueWithArrowInId) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "-->\n"
      "00:01:00.000 --> 01:00:00.000\n"
      "subtitle\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_FALSE(parser_->Flush());
}

TEST_F(WebVttParserTest, ParseOneCueWithId) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "id\n"
      "00:01:00.000 --> 01:00:00.000\n"
      "subtitle\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  ASSERT_EQ(samples_.size(), 1u);
  EXPECT_EQ(samples_[0]->id(), "id");
  ExpectPlainCueWithBody(samples_[0]->body(), "subtitle");
}

TEST_F(WebVttParserTest, ParseOneEmptyCueWithId) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "id\n"
      "00:01:00.000 --> 01:00:00.000\n"
      "\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  ASSERT_EQ(samples_.size(), 1u);
  EXPECT_EQ(samples_[0]->id(), "id");
  ExpectPlainCueWithBody(samples_[0]->body(), "");
}

TEST_F(WebVttParserTest, ParseSettingSize) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "00:01:00.000 --> 01:00:00.000 size:50%\n"
      "subtitle\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  ASSERT_EQ(samples_.size(), 1u);
  ASSERT_TRUE(samples_[0]->settings().width);
  EXPECT_EQ(samples_[0]->settings().width->type, TextUnitType::kPercent);
  EXPECT_EQ(samples_[0]->settings().width->value, 50.0f);
}

TEST_F(WebVttParserTest, ParseOneCueWithManySettings) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "00:01:00.000 --> 01:00:00.000 line:5 vertical:lr region:foo"
      " align:right position:20%\n"
      "subtitle\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  ASSERT_EQ(samples_.size(), 1u);
  EXPECT_EQ(samples_[0]->settings().writing_direction,
            WritingDirection::kVerticalGrowingRight);
  EXPECT_EQ(samples_[0]->settings().text_alignment, TextAlignment::kRight);
  EXPECT_FALSE(samples_[0]->settings().width);
  ASSERT_TRUE(samples_[0]->settings().position);
  EXPECT_EQ(samples_[0]->settings().position->type, TextUnitType::kPercent);
  EXPECT_EQ(samples_[0]->settings().position->value, 20.0f);
  ASSERT_TRUE(samples_[0]->settings().line);
  EXPECT_EQ(samples_[0]->settings().line->type, TextUnitType::kLines);
  EXPECT_EQ(samples_[0]->settings().line->value, 5.0f);
}

TEST_F(WebVttParserTest, ParseRegions) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "REGION\n"
      "id:foo\n"
      "width:20%\n"
      "lines:6\n"
      "viewportanchor:25%,75%\n"
      "scroll:up\n"
      "\n"
      "00:01:00.000 --> 01:00:00.000 region:foo\n"
      "subtitle\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  ASSERT_EQ(samples_.size(), 1u);

  auto* stream = static_cast<const TextStreamInfo*>(streams_[0].get());
  const auto& regions = stream->regions();
  ASSERT_EQ(regions.size(), 1u);
  ASSERT_EQ(regions.count("foo"), 1u);

  EXPECT_EQ(samples_[0]->settings().region, "foo");
  const auto& region = regions.at("foo");
  EXPECT_EQ(region.width.value, 20.0f);
  EXPECT_EQ(region.width.type, TextUnitType::kPercent);
  EXPECT_EQ(region.height.value, 6.0f);
  EXPECT_EQ(region.height.type, TextUnitType::kLines);
  EXPECT_EQ(region.window_anchor_x.value, 25.0f);
  EXPECT_EQ(region.window_anchor_x.type, TextUnitType::kPercent);
  EXPECT_EQ(region.window_anchor_y.value, 75.0f);
  EXPECT_EQ(region.window_anchor_y.type, TextUnitType::kPercent);
  EXPECT_TRUE(region.scroll);
}

TEST_F(WebVttParserTest, ParseRegionsMaxPercent) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "REGION\n"
      "id:foo\n"
      "width:20%\n"
      "lines:6\n"
      "viewportanchor:25%,100%\n"
      "scroll:up\n"
      "\n"
      "00:01:00.000 --> 01:00:00.000 region:foo\n"
      "subtitle\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  ASSERT_EQ(samples_.size(), 1u);

  auto* stream = static_cast<const TextStreamInfo*>(streams_[0].get());
  const auto& regions = stream->regions();
  ASSERT_EQ(regions.size(), 1u);
  ASSERT_EQ(regions.count("foo"), 1u);

  EXPECT_EQ(samples_[0]->settings().region, "foo");
  const auto& region = regions.at("foo");
  EXPECT_EQ(region.width.value, 20.0f);
  EXPECT_EQ(region.width.type, TextUnitType::kPercent);
  EXPECT_EQ(region.height.value, 6.0f);
  EXPECT_EQ(region.height.type, TextUnitType::kLines);
  EXPECT_EQ(region.window_anchor_x.value, 25.0f);
  EXPECT_EQ(region.window_anchor_x.type, TextUnitType::kPercent);
  EXPECT_EQ(region.window_anchor_y.value, 100.0f);
  EXPECT_EQ(region.window_anchor_y.type, TextUnitType::kPercent);
  EXPECT_TRUE(region.scroll);
}

// Verify that a typical case with mulitple cues work.
TEST_F(WebVttParserTest, ParseMultipleCues) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "00:00:01.000 --> 00:00:05.200\n"
      "subtitle A\n"
      "\n"
      "00:00:02.321 --> 00:00:07.000\n"
      "subtitle B\n"
      "\n"
      "00:00:05.800 --> 00:00:08.000\n"
      "subtitle C\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  ASSERT_EQ(samples_.size(), 3u);

  EXPECT_EQ(samples_[0]->start_time(), 1000u);
  EXPECT_EQ(samples_[0]->duration(), 4200u);
  ExpectPlainCueWithBody(samples_[0]->body(), "subtitle A");
  EXPECT_EQ(samples_[1]->start_time(), 2321u);
  EXPECT_EQ(samples_[1]->duration(), 4679u);
  ExpectPlainCueWithBody(samples_[1]->body(), "subtitle B");
  EXPECT_EQ(samples_[2]->start_time(), 5800u);
  EXPECT_EQ(samples_[2]->duration(), 2200u);
  ExpectPlainCueWithBody(samples_[2]->body(), "subtitle C");
}

// Verify that a typical case with mulitple cues work even when comments are
// present.
TEST_F(WebVttParserTest, ParseWithComments) {
  const uint8_t text[] =
      "WEBVTT\n"
      "\n"
      "NOTE This is a one line comment\n"
      "\n"
      "00:00:01.000 --> 00:00:05.200\n"
      "subtitle A\n"
      "\n"
      "NOTE\n"
      "This is a multi-line comment\n"
      "\n"
      "00:00:02.321 --> 00:00:07.000\n"
      "subtitle B\n"
      "\n"
      "NOTE This is a single line comment that\n"
      "spans two lines\n"
      "\n"
      "NOTE\tThis is a comment that using a tab\n"
      "\n"
      "00:00:05.800 --> 00:00:08.000\n"
      "subtitle C\n";

  ASSERT_NO_FATAL_FAILURE(SetUpAndInitialize());

  ASSERT_TRUE(parser_->Parse(text, sizeof(text) - 1));
  ASSERT_TRUE(parser_->Flush());

  ASSERT_EQ(streams_.size(), 1u);
  ASSERT_EQ(samples_.size(), 3u);

  ExpectPlainCueWithBody(samples_[0]->body(), "subtitle A");
  ExpectPlainCueWithBody(samples_[1]->body(), "subtitle B");
  ExpectPlainCueWithBody(samples_[2]->body(), "subtitle C");
}

}  // namespace media
}  // namespace shaka