// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "media/parsers/jpeg_parser.h"

#include <stdint.h>

#include "base/files/memory_mapped_file.h"
#include "base/path_service.h"
#include "base/test/scoped_feature_list.h"
#include "media/base/media_switches.h"
#include "media/base/test_data_util.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace media {

class JpegParserTest : public testing::Test {};

TEST_F(JpegParserTest, Parsing) {
  base::FilePath data_dir;
  ASSERT_TRUE(base::PathService::Get(base::DIR_SRC_TEST_DATA_ROOT, &data_dir));

  // This sample frame is captured from Chromebook Pixel
  base::FilePath file_path = data_dir.AppendASCII("media")
                                 .AppendASCII("test")
                                 .AppendASCII("data")
                                 .AppendASCII("pixel-1280x720.jpg");

  base::MemoryMappedFile stream;
  ASSERT_TRUE(stream.Initialize(file_path))
      << "Couldn't open stream file: " << file_path.MaybeAsASCII();

  JpegParseResult result;
  ASSERT_TRUE(ParseJpegPicture(stream.bytes(), &result));

  // Verify selected fields

  // SOF fields
  EXPECT_EQ(1280, result.frame_header.visible_width);
  EXPECT_EQ(720, result.frame_header.visible_height);
  EXPECT_EQ(1280, result.frame_header.coded_width);
  EXPECT_EQ(720, result.frame_header.coded_height);
  EXPECT_EQ(3, result.frame_header.num_components);
  EXPECT_EQ(1, result.frame_header.components[0].id);
  EXPECT_EQ(2, result.frame_header.components[0].horizontal_sampling_factor);
  EXPECT_EQ(1, result.frame_header.components[0].vertical_sampling_factor);
  EXPECT_EQ(0, result.frame_header.components[0].quantization_table_selector);
  EXPECT_EQ(2, result.frame_header.components[1].id);
  EXPECT_EQ(1, result.frame_header.components[1].horizontal_sampling_factor);
  EXPECT_EQ(1, result.frame_header.components[1].vertical_sampling_factor);
  EXPECT_EQ(1, result.frame_header.components[1].quantization_table_selector);
  EXPECT_EQ(3, result.frame_header.components[2].id);
  EXPECT_EQ(1, result.frame_header.components[2].horizontal_sampling_factor);
  EXPECT_EQ(1, result.frame_header.components[2].vertical_sampling_factor);
  EXPECT_EQ(1, result.frame_header.components[2].quantization_table_selector);

  // DRI fields
  EXPECT_EQ(0, result.restart_interval);

  // DQT fields
  EXPECT_TRUE(result.q_table[0].valid);
  EXPECT_TRUE(result.q_table[1].valid);
  EXPECT_FALSE(result.q_table[2].valid);
  EXPECT_FALSE(result.q_table[3].valid);

  // DHT fields (no DHT marker)
  EXPECT_FALSE(result.dc_table[0].valid);
  EXPECT_FALSE(result.ac_table[0].valid);
  EXPECT_FALSE(result.dc_table[1].valid);
  EXPECT_FALSE(result.ac_table[1].valid);

  // SOS fields
  EXPECT_EQ(3, result.scan.num_components);
  EXPECT_EQ(1, result.scan.components[0].component_selector);
  EXPECT_EQ(0, result.scan.components[0].dc_selector);
  EXPECT_EQ(0, result.scan.components[0].ac_selector);
  EXPECT_EQ(2, result.scan.components[1].component_selector);
  EXPECT_EQ(1, result.scan.components[1].dc_selector);
  EXPECT_EQ(1, result.scan.components[1].ac_selector);
  EXPECT_EQ(3, result.scan.components[2].component_selector);
  EXPECT_EQ(1, result.scan.components[2].dc_selector);
  EXPECT_EQ(1, result.scan.components[2].ac_selector);
  EXPECT_EQ(121148u, result.data.size());
  EXPECT_EQ(121358u, result.image_size);
}

TEST_F(JpegParserTest, TrailingZerosShouldBeIgnored) {
  base::FilePath data_dir;
  ASSERT_TRUE(base::PathService::Get(base::DIR_SRC_TEST_DATA_ROOT, &data_dir));
  base::FilePath file_path =
      data_dir.AppendASCII("media")
          .AppendASCII("test")
          .AppendASCII("data")
          .AppendASCII("pixel-1280x720-trailing-zeros.jpg");

  base::MemoryMappedFile stream;
  ASSERT_TRUE(stream.Initialize(file_path))
      << "Couldn't open stream file: " << file_path.MaybeAsASCII();

  JpegParseResult result;
  ASSERT_TRUE(ParseJpegPicture(stream.bytes(), &result));

  // Verify selected fields

  // SOS fields
  EXPECT_EQ(121148u, result.data.size());
  EXPECT_EQ(121358u, result.image_size);
}

TEST_F(JpegParserTest, CodedSizeNotEqualVisibleSize) {
  base::FilePath data_dir;
  ASSERT_TRUE(base::PathService::Get(base::DIR_SRC_TEST_DATA_ROOT, &data_dir));

  base::FilePath file_path = data_dir.AppendASCII("media")
                                 .AppendASCII("test")
                                 .AppendASCII("data")
                                 .AppendASCII("blank-1x1.jpg");

  base::MemoryMappedFile stream;
  ASSERT_TRUE(stream.Initialize(file_path))
      << "Couldn't open stream file: " << file_path.MaybeAsASCII();

  JpegParseResult result;
  ASSERT_TRUE(ParseJpegPicture(stream.bytes(), &result));

  EXPECT_EQ(1, result.frame_header.visible_width);
  EXPECT_EQ(1, result.frame_header.visible_height);
  // The sampling factor of the given image is 2:2, so coded size is 16x16
  EXPECT_EQ(16, result.frame_header.coded_width);
  EXPECT_EQ(16, result.frame_header.coded_height);
  EXPECT_EQ(2, result.frame_header.components[0].horizontal_sampling_factor);
  EXPECT_EQ(2, result.frame_header.components[0].vertical_sampling_factor);
}

TEST_F(JpegParserTest, ParsingFail) {
  const uint8_t data[] = {0, 1, 2, 3};  // not jpeg
  JpegParseResult result;
  ASSERT_FALSE(ParseJpegPicture(data, &result));
}

static std::vector<uint8_t> CreateJpegWithCustomHuffmanTable(
    uint8_t table_class,
    size_t num_symbols) {
  std::vector<uint8_t> jpeg = {
      0xff,
      0xd8,  // SOI
      // DQT: 64 bytes
      0xff,
      0xdb,
      0x00,
      0x43,
      0x00,
  };
  jpeg.insert(jpeg.end(), 64, 16);

  // DHT: table_id=0
  uint16_t dht_payload_size = 2 + 1 + 16 + num_symbols;
  std::vector<uint8_t> dht = {
      0xff,
      0xc4,
      static_cast<uint8_t>(dht_payload_size >> 8),
      static_cast<uint8_t>(dht_payload_size & 0xff),
      static_cast<uint8_t>((table_class << 4) | 0x00),
  };
  // Distribute num_symbols across 16 code length bins (each bin <= 255)
  size_t remaining = num_symbols;
  for (int i = 0; i < 16; ++i) {
    uint8_t count = static_cast<uint8_t>(std::min<size_t>(remaining, 255));
    dht.push_back(count);
    remaining -= count;
  }
  for (size_t i = 0; i < num_symbols; ++i) {
    dht.push_back(static_cast<uint8_t>(i & 0xff));
  }
  jpeg.insert(jpeg.end(), dht.begin(), dht.end());

  // SOF0: 16x16, 1 component
  std::vector<uint8_t> sof0 = {
      0xff, 0xc0, 0x00, 0x0b, 0x08, 0x00, 0x10,
      0x00, 0x10, 0x01, 0x01, 0x11, 0x00,
  };
  jpeg.insert(jpeg.end(), sof0.begin(), sof0.end());

  // SOS: 1 component
  std::vector<uint8_t> sos = {
      0xff, 0xda, 0x00, 0x08, 0x01, 0x01, 0x00, 0x00, 0x3f, 0x00,
  };
  jpeg.insert(jpeg.end(), sos.begin(), sos.end());

  // Scan payload & EOI
  jpeg.push_back(0x00);
  jpeg.push_back(0x00);
  jpeg.push_back(0xff);
  jpeg.push_back(0xd9);

  return jpeg;
}

TEST_F(JpegParserTest, DCHuffmanTableCodeLengthLimit) {
  // DC table with 12 symbols is the maximum allowed by ITU-T T.81 baseline ->
  // OK.
  {
    auto jpeg_dc_12 = CreateJpegWithCustomHuffmanTable(/*table_class=*/0, 12);
    JpegParseResult result;
    EXPECT_TRUE(ParseJpegPicture(jpeg_dc_12, &result));
    EXPECT_TRUE(result.dc_table[0].valid);
  }

  // DC table with > 12 symbols (e.g. 13 or 16) must be rejected.
  {
    auto jpeg_dc_13 = CreateJpegWithCustomHuffmanTable(/*table_class=*/0, 13);
    JpegParseResult result;
    EXPECT_FALSE(ParseJpegPicture(jpeg_dc_13, &result));
  }

  {
    auto jpeg_dc_16 = CreateJpegWithCustomHuffmanTable(/*table_class=*/0, 16);
    JpegParseResult result;
    EXPECT_FALSE(ParseJpegPicture(jpeg_dc_16, &result));
  }
}

TEST_F(JpegParserTest, ACHuffmanTableCodeLengthLimit) {
  // AC table with 162 symbols is the maximum allowed -> OK.
  {
    auto jpeg_ac_162 = CreateJpegWithCustomHuffmanTable(/*table_class=*/1, 162);
    JpegParseResult result;
    EXPECT_TRUE(ParseJpegPicture(jpeg_ac_162, &result));
    EXPECT_TRUE(result.ac_table[0].valid);
  }

  // AC table with > 162 symbols must be rejected.
  {
    auto jpeg_ac_163 = CreateJpegWithCustomHuffmanTable(/*table_class=*/1, 163);
    JpegParseResult result;
    EXPECT_FALSE(ParseJpegPicture(jpeg_ac_163, &result));
  }
}

}  // namespace media