// Copyright 2018 The PDFium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "core/fpdfapi/render/cpdf_docrenderdata.h"

#include <iterator>
#include <memory>
#include <utility>

#include "core/fpdfapi/page/cpdf_transferfunc.h"
#include "core/fpdfapi/parser/cpdf_array.h"
#include "core/fpdfapi/parser/cpdf_dictionary.h"
#include "core/fpdfapi/parser/cpdf_number.h"
#include "core/fpdfapi/parser/cpdf_stream.h"
#include "core/fxcrt/data_vector.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace {

constexpr uint8_t kExpectedType0FunctionSamples[] = {
    0,   3,   6,   9,   13,  16,  19,  22,  25,  28,  31,  34,  37,  40,  43,
    46,  49,  52,  55,  58,  60,  63,  66,  68,  71,  74,  76,  79,  81,  84,
    86,  88,  90,  93,  95,  97,  99,  101, 103, 105, 106, 108, 110, 111, 113,
    114, 115, 117, 118, 119, 120, 121, 122, 123, 124, 125, 125, 126, 126, 127,
    127, 127, 127, 127, 127, 127, 127, 127, 127, 126, 126, 125, 125, 124, 123,
    123, 122, 121, 120, 119, 117, 116, 115, 113, 112, 110, 109, 107, 105, 104,
    102, 100, 98,  96,  94,  92,  89,  87,  85,  82,  80,  77,  75,  72,  70,
    67,  64,  62,  59,  56,  53,  50,  48,  45,  42,  39,  36,  33,  30,  27,
    23,  20,  17,  14,  11,  8,   5,   2,   254, 251, 248, 245, 242, 239, 236,
    233, 229, 226, 223, 220, 217, 214, 211, 208, 206, 203, 200, 197, 194, 192,
    189, 186, 184, 181, 179, 176, 174, 171, 169, 167, 164, 162, 160, 158, 156,
    154, 152, 151, 149, 147, 146, 144, 143, 141, 140, 139, 137, 136, 135, 134,
    133, 133, 132, 131, 131, 130, 130, 129, 129, 129, 129, 129, 129, 129, 129,
    129, 129, 130, 130, 131, 131, 132, 133, 134, 135, 136, 137, 138, 139, 141,
    142, 143, 145, 146, 148, 150, 151, 153, 155, 157, 159, 161, 163, 166, 168,
    170, 172, 175, 177, 180, 182, 185, 188, 190, 193, 196, 198, 201, 204, 207,
    210, 213, 216, 219, 222, 225, 228, 231, 234, 237, 240, 243, 247, 250, 253,
    0};

constexpr uint8_t kExpectedType2FunctionSamples[] = {
    26, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
    25, 25, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
    24, 24, 24, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23,
    23, 23, 23, 23, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22,
    22, 22, 22, 22, 22, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21,
    21, 21, 21, 21, 21, 21, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20,
    20, 20, 20, 20, 20, 20, 20, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19,
    19, 19, 19, 19, 19, 19, 19, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18,
    18, 18, 18, 18, 18, 18, 18, 18, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17,
    17, 17, 17, 17, 17, 17, 17, 17, 17, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16,
    16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 15, 15, 15, 15, 15, 15, 15, 15,
    15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 14, 14, 14, 14, 14, 14, 14,
    14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 13, 13, 13, 13, 13, 13,
    13, 13, 13, 13, 13, 13, 13, 13, 13};

constexpr uint8_t kExpectedType4FunctionSamples[] = {
    25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
    25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
    25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
    25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
    25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
    25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
    25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
    25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
    25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 26,
    26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
    26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
    26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
    26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
    26, 26, 26, 26, 26, 26, 26, 26, 26};

RetainPtr<CPDF_Stream> CreateType0FunctionStream() {
  auto func_dict = pdfium::MakeRetain<CPDF_Dictionary>();
  func_dict->SetNewFor<CPDF_Number>("FunctionType", 0);
  func_dict->SetNewFor<CPDF_Number>("BitsPerSample", 8);

  auto domain_array = func_dict->SetNewFor<CPDF_Array>("Domain");
  domain_array->AppendNew<CPDF_Number>(0);
  domain_array->AppendNew<CPDF_Number>(1);

  auto range_array = func_dict->SetNewFor<CPDF_Array>("Range");
  range_array->AppendNew<CPDF_Number>(0);
  range_array->AppendNew<CPDF_Number>(0.5f);

  auto size_array = func_dict->SetNewFor<CPDF_Array>("Size");
  size_array->AppendNew<CPDF_Number>(4);

  static constexpr uint8_t kContents[] = "1234";
  return pdfium::MakeRetain<CPDF_Stream>(
      DataVector<uint8_t>(std::begin(kContents), std::end(kContents)),
      std::move(func_dict));
}

RetainPtr<CPDF_Dictionary> CreateType2FunctionDict() {
  auto func_dict = pdfium::MakeRetain<CPDF_Dictionary>();
  func_dict->SetNewFor<CPDF_Number>("FunctionType", 2);
  func_dict->SetNewFor<CPDF_Number>("N", 1);

  auto domain_array = func_dict->SetNewFor<CPDF_Array>("Domain");
  domain_array->AppendNew<CPDF_Number>(0);
  domain_array->AppendNew<CPDF_Number>(1);

  auto c0_array = func_dict->SetNewFor<CPDF_Array>("C0");
  c0_array->AppendNew<CPDF_Number>(0.1f);
  c0_array->AppendNew<CPDF_Number>(0.2f);
  c0_array->AppendNew<CPDF_Number>(0.8f);

  auto c1_array = func_dict->SetNewFor<CPDF_Array>("C1");
  c1_array->AppendNew<CPDF_Number>(0.05f);
  c1_array->AppendNew<CPDF_Number>(0.01f);
  c1_array->AppendNew<CPDF_Number>(0.4f);

  return func_dict;
}

RetainPtr<CPDF_Stream> CreateType4FunctionStream() {
  auto func_dict = pdfium::MakeRetain<CPDF_Dictionary>();
  func_dict->SetNewFor<CPDF_Number>("FunctionType", 4);

  auto domain_array = func_dict->SetNewFor<CPDF_Array>("Domain");
  domain_array->AppendNew<CPDF_Number>(0);
  domain_array->AppendNew<CPDF_Number>(1);

  auto range_array = func_dict->SetNewFor<CPDF_Array>("Range");
  range_array->AppendNew<CPDF_Number>(-1);
  range_array->AppendNew<CPDF_Number>(1);

  static constexpr uint8_t kContents[] = "{ 360 mul sin 2 div }";
  return pdfium::MakeRetain<CPDF_Stream>(
      DataVector<uint8_t>(std::begin(kContents), std::end(kContents)),
      std::move(func_dict));
}

RetainPtr<CPDF_Stream> CreateBadType4FunctionStream() {
  auto func_dict = pdfium::MakeRetain<CPDF_Dictionary>();
  func_dict->SetNewFor<CPDF_Number>("FunctionType", 4);

  auto domain_array = func_dict->SetNewFor<CPDF_Array>("Domain");
  domain_array->AppendNew<CPDF_Number>(0);
  domain_array->AppendNew<CPDF_Number>(1);

  auto range_array = func_dict->SetNewFor<CPDF_Array>("Range");
  range_array->AppendNew<CPDF_Number>(-1);
  range_array->AppendNew<CPDF_Number>(1);

  static constexpr uint8_t kContents[] = "garbage";
  return pdfium::MakeRetain<CPDF_Stream>(
      DataVector<uint8_t>(std::begin(kContents), std::end(kContents)),
      std::move(func_dict));
}

class TestDocRenderData : public CPDF_DocRenderData {
 public:
  TestDocRenderData() = default;

  RetainPtr<CPDF_TransferFunc> CreateTransferFuncForTesting(
      RetainPtr<const CPDF_Object> pObj) const {
    return CreateTransferFunc(std::move(pObj));
  }
};

TEST(CPDF_DocRenderDataTest, TransferFunctionOne) {
  RetainPtr<CPDF_Dictionary> func_dict = CreateType2FunctionDict();

  TestDocRenderData render_data;
  auto func = render_data.CreateTransferFuncForTesting(func_dict);
  ASSERT_TRUE(func);
  EXPECT_FALSE(func->GetIdentity());

  auto r_samples = func->GetSamplesR();
  auto g_samples = func->GetSamplesG();
  auto b_samples = func->GetSamplesB();
  ASSERT_EQ(std::size(kExpectedType2FunctionSamples), r_samples.size());
  ASSERT_EQ(std::size(kExpectedType2FunctionSamples), g_samples.size());
  ASSERT_EQ(std::size(kExpectedType2FunctionSamples), b_samples.size());

  for (size_t i = 0; i < std::size(kExpectedType2FunctionSamples); ++i) {
    EXPECT_EQ(kExpectedType2FunctionSamples[i], r_samples[i]);
    EXPECT_EQ(kExpectedType2FunctionSamples[i], g_samples[i]);
    EXPECT_EQ(kExpectedType2FunctionSamples[i], b_samples[i]);
  }

  EXPECT_EQ(0x000d0d0du, func->TranslateColor(0x00ffffff));
  EXPECT_EQ(0x000d1a1au, func->TranslateColor(0x00ff0000));
  EXPECT_EQ(0x001a0d1au, func->TranslateColor(0x0000ff00));
  EXPECT_EQ(0x001a1a0du, func->TranslateColor(0x000000ff));
  EXPECT_EQ(0x000f0f0fu, func->TranslateColor(0x00cccccc));
  EXPECT_EQ(0x00191715u, func->TranslateColor(0x00123456));
  EXPECT_EQ(0x000d0d0du, func->TranslateColor(0xffffffff));
  EXPECT_EQ(0x001a1a1au, func->TranslateColor(0xff000000));
  EXPECT_EQ(0x000d0d0du, func->TranslateColor(0xccffffff));
  EXPECT_EQ(0x001a1a1au, func->TranslateColor(0x99000000));
}

TEST(CPDF_DocRenderDataTest, TransferFunctionArray) {
  auto func_array = pdfium::MakeRetain<CPDF_Array>();
  func_array->Append(CreateType0FunctionStream());
  func_array->Append(CreateType2FunctionDict());
  func_array->Append(CreateType4FunctionStream());

  TestDocRenderData render_data;
  auto func = render_data.CreateTransferFuncForTesting(func_array);
  ASSERT_TRUE(func);
  EXPECT_FALSE(func->GetIdentity());

  auto r_samples = func->GetSamplesR();
  auto g_samples = func->GetSamplesG();
  auto b_samples = func->GetSamplesB();
  ASSERT_EQ(std::size(kExpectedType0FunctionSamples), r_samples.size());
  ASSERT_EQ(std::size(kExpectedType2FunctionSamples), g_samples.size());
  ASSERT_EQ(std::size(kExpectedType4FunctionSamples), b_samples.size());

  for (size_t i = 0; i < std::size(kExpectedType2FunctionSamples); ++i) {
    EXPECT_EQ(kExpectedType0FunctionSamples[i], r_samples[i]);
    EXPECT_EQ(kExpectedType2FunctionSamples[i], g_samples[i]);
    EXPECT_EQ(kExpectedType4FunctionSamples[i], b_samples[i]);
  }

  EXPECT_EQ(0x001a0d00u, func->TranslateColor(0x00ffffff));
  EXPECT_EQ(0x001a1a00u, func->TranslateColor(0x00ff0000));
  EXPECT_EQ(0x00190d00u, func->TranslateColor(0x0000ff00));
  EXPECT_EQ(0x00191a00u, func->TranslateColor(0x000000ff));
  EXPECT_EQ(0x001a0f87u, func->TranslateColor(0x00cccccc));
  EXPECT_EQ(0x0019176du, func->TranslateColor(0x00123456));
  EXPECT_EQ(0x001a0d00u, func->TranslateColor(0xffffffff));
  EXPECT_EQ(0x00191a00u, func->TranslateColor(0xff000000));
  EXPECT_EQ(0x001a0d00u, func->TranslateColor(0xccffffff));
  EXPECT_EQ(0x00191a00u, func->TranslateColor(0x99000000));
}

TEST(CPDF_DocRenderDataTest, BadTransferFunctions) {
  {
    auto func_stream = CreateBadType4FunctionStream();

    TestDocRenderData render_data;
    auto func = render_data.CreateTransferFuncForTesting(func_stream);
    EXPECT_FALSE(func);
  }

  {
    auto func_array = pdfium::MakeRetain<CPDF_Array>();

    TestDocRenderData render_data;
    auto func = render_data.CreateTransferFuncForTesting(func_array);
    EXPECT_FALSE(func);
  }

  {
    auto func_array = pdfium::MakeRetain<CPDF_Array>();
    func_array->Append(CreateType0FunctionStream());
    func_array->Append(CreateType2FunctionDict());
    func_array->Append(CreateBadType4FunctionStream());

    TestDocRenderData render_data;
    auto func = render_data.CreateTransferFuncForTesting(func_array);
    EXPECT_FALSE(func);
  }
}

}  // namespace