// Copyright 2017 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/edit/cpdf_pagecontentgenerator.h"

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

#include "core/fpdfapi/font/cpdf_font.h"
#include "core/fpdfapi/page/cpdf_colorspace.h"
#include "core/fpdfapi/page/cpdf_docpagedata.h"
#include "core/fpdfapi/page/cpdf_form.h"
#include "core/fpdfapi/page/cpdf_page.h"
#include "core/fpdfapi/page/cpdf_pathobject.h"
#include "core/fpdfapi/page/cpdf_textobject.h"
#include "core/fpdfapi/page/cpdf_textstate.h"
#include "core/fpdfapi/page/test_with_page_module.h"
#include "core/fpdfapi/parser/cpdf_dictionary.h"
#include "core/fpdfapi/parser/cpdf_document.h"
#include "core/fpdfapi/parser/cpdf_name.h"
#include "core/fpdfapi/parser/cpdf_parser.h"
#include "core/fpdfapi/parser/cpdf_reference.h"
#include "core/fpdfapi/parser/cpdf_stream.h"
#include "core/fpdfapi/parser/cpdf_test_document.h"
#include "core/fxcrt/data_vector.h"
#include "core/fxge/cfx_fillrenderoptions.h"
#include "testing/gtest/include/gtest/gtest.h"

class CPDFPageContentGeneratorTest : public TestWithPageModule {
 protected:
  void TestProcessPath(CPDF_PageContentGenerator* pGen,
                       fxcrt::ostringstream* buf,
                       CPDF_PathObject* pPathObj) {
    pGen->ProcessPath(buf, pPathObj);
  }

  RetainPtr<const CPDF_Dictionary> TestGetResource(
      CPDF_PageContentGenerator* pGen,
      const ByteString& type,
      const ByteString& name) {
    RetainPtr<const CPDF_Dictionary> pResources =
        pGen->m_pObjHolder->GetResources();
    return pResources->GetDictFor(type)->GetDictFor(name);
  }

  void TestProcessText(CPDF_PageContentGenerator* pGen,
                       fxcrt::ostringstream* buf,
                       CPDF_TextObject* pTextObj) {
    pGen->ProcessText(buf, pTextObj);
  }
};

TEST_F(CPDFPageContentGeneratorTest, ProcessRect) {
  auto pPathObj = std::make_unique<CPDF_PathObject>();
  pPathObj->set_stroke(true);
  pPathObj->set_filltype(CFX_FillRenderOptions::FillType::kEvenOdd);
  pPathObj->path().AppendRect(10, 5, 13, 30);

  auto dummy_page_dict = pdfium::MakeRetain<CPDF_Dictionary>();
  auto pTestPage = pdfium::MakeRetain<CPDF_Page>(nullptr, dummy_page_dict);
  CPDF_PageContentGenerator generator(pTestPage.Get());
  fxcrt::ostringstream buf;
  TestProcessPath(&generator, &buf, pPathObj.get());
  EXPECT_EQ("q 1 0 0 1 0 0 cm 10 5 3 25 re B* Q\n", ByteString(buf));

  pPathObj = std::make_unique<CPDF_PathObject>();
  pPathObj->path().AppendPoint(CFX_PointF(0, 0), CFX_Path::Point::Type::kMove);
  pPathObj->path().AppendPoint(CFX_PointF(5.2f, 0),
                               CFX_Path::Point::Type::kLine);
  pPathObj->path().AppendPoint(CFX_PointF(5.2f, 3.78f),
                               CFX_Path::Point::Type::kLine);
  pPathObj->path().AppendPointAndClose(CFX_PointF(0, 3.78f),
                                       CFX_Path::Point::Type::kLine);
  buf.str("");
  TestProcessPath(&generator, &buf, pPathObj.get());
  EXPECT_EQ("q 1 0 0 1 0 0 cm 0 0 5.1999998 3.78 re n Q\n", ByteString(buf));
}

TEST_F(CPDFPageContentGeneratorTest, BUG_937) {
  static const std::vector<float> rgb = {0.000000000000000000001f, 0.7f, 0.35f};
  RetainPtr<CPDF_ColorSpace> pCS =
      CPDF_ColorSpace::GetStockCS(CPDF_ColorSpace::Family::kDeviceRGB);
  {
    auto pPathObj = std::make_unique<CPDF_PathObject>();
    pPathObj->set_filltype(CFX_FillRenderOptions::FillType::kWinding);

    // Test code in ProcessPath that generates re operator
    pPathObj->path().AppendRect(0.000000000000000000001,
                                0.000000000000000000001, 100, 100);

    pPathObj->mutable_color_state().SetFillColor(pCS, rgb);
    pPathObj->mutable_color_state().SetStrokeColor(pCS, rgb);
    pPathObj->mutable_graph_state().SetLineWidth(200000000000000000001.0);
    pPathObj->Transform(CFX_Matrix(1, 0, 0, 1, 0.000000000000000000001,
                                   200000000000000.000002));

    auto dummy_page_dict = pdfium::MakeRetain<CPDF_Dictionary>();
    auto pTestPage = pdfium::MakeRetain<CPDF_Page>(nullptr, dummy_page_dict);
    CPDF_PageContentGenerator generator(pTestPage.Get());
    fxcrt::ostringstream buf;
    TestProcessPath(&generator, &buf, pPathObj.get());
    EXPECT_EQ(
        "q 0 0.701961 0.34902 rg 0 0.701961 0.34902 RG 200000000000000000000 w"
        " 1 0 0 1 .00000000000000000000099999997 200000000000000 cm .000000000"
        "00000000000099999997 .00000000000000000000099999997 100 100 re f Q\n",
        ByteString(buf));
  }

  {
    // Test code in ProcessPath that handles bezier operator
    auto pPathObj = std::make_unique<CPDF_PathObject>();
    pPathObj->mutable_color_state().SetFillColor(pCS, rgb);
    pPathObj->mutable_color_state().SetStrokeColor(pCS, rgb);
    pPathObj->mutable_graph_state().SetLineWidth(2.000000000000000000001);
    pPathObj->Transform(CFX_Matrix(1, 0, 0, 1, 432, 500000000000000.000002));

    pPathObj->set_filltype(CFX_FillRenderOptions::FillType::kWinding);
    pPathObj->path().AppendPoint(CFX_PointF(0.000000000000000000001f, 4.67f),
                                 CFX_Path::Point::Type::kMove);
    pPathObj->path().AppendPoint(
        CFX_PointF(0.000000000000000000001, 100000000000000.000002),
        CFX_Path::Point::Type::kLine);
    pPathObj->path().AppendPoint(CFX_PointF(0.0000000000001f, 3.15f),
                                 CFX_Path::Point::Type::kBezier);
    pPathObj->path().AppendPoint(CFX_PointF(3.57f, 2.98f),
                                 CFX_Path::Point::Type::kBezier);
    pPathObj->path().AppendPointAndClose(
        CFX_PointF(53.4f, 5000000000000000000.00000000000000004),
        CFX_Path::Point::Type::kBezier);
    auto dummy_page_dict = pdfium::MakeRetain<CPDF_Dictionary>();
    auto pTestPage = pdfium::MakeRetain<CPDF_Page>(nullptr, dummy_page_dict);
    CPDF_PageContentGenerator generator(pTestPage.Get());
    fxcrt::ostringstream buf;

    TestProcessPath(&generator, &buf, pPathObj.get());
    EXPECT_EQ(
        "q 0 0.701961 0.34902 rg 0 0.701961 0.34902 RG 2 w 1 0 0 1 432 4999999"
        "90000000 cm .00000000000000000000099999997 4.6700001 m .0000000000000"
        "0000000099999997 100000000000000 l .000000000000099999998 3.1500001 3"
        ".5699999 2.98 53.400002 5000000000000000000 c h f Q\n",
        ByteString(buf));
  }
}

TEST_F(CPDFPageContentGeneratorTest, ProcessPath) {
  auto pPathObj = std::make_unique<CPDF_PathObject>();
  pPathObj->set_filltype(CFX_FillRenderOptions::FillType::kWinding);
  pPathObj->path().AppendPoint(CFX_PointF(3.102f, 4.67f),
                               CFX_Path::Point::Type::kMove);
  pPathObj->path().AppendPoint(CFX_PointF(5.45f, 0.29f),
                               CFX_Path::Point::Type::kLine);
  pPathObj->path().AppendPoint(CFX_PointF(4.24f, 3.15f),
                               CFX_Path::Point::Type::kBezier);
  pPathObj->path().AppendPoint(CFX_PointF(4.65f, 2.98f),
                               CFX_Path::Point::Type::kBezier);
  pPathObj->path().AppendPoint(CFX_PointF(3.456f, 0.24f),
                               CFX_Path::Point::Type::kBezier);
  pPathObj->path().AppendPoint(CFX_PointF(10.6f, 11.15f),
                               CFX_Path::Point::Type::kLine);
  pPathObj->path().AppendPoint(CFX_PointF(11, 12.5f),
                               CFX_Path::Point::Type::kLine);
  pPathObj->path().AppendPoint(CFX_PointF(11.46f, 12.67f),
                               CFX_Path::Point::Type::kBezier);
  pPathObj->path().AppendPoint(CFX_PointF(11.84f, 12.96f),
                               CFX_Path::Point::Type::kBezier);
  pPathObj->path().AppendPointAndClose(CFX_PointF(12, 13.64f),
                                       CFX_Path::Point::Type::kBezier);

  auto dummy_page_dict = pdfium::MakeRetain<CPDF_Dictionary>();
  auto pTestPage = pdfium::MakeRetain<CPDF_Page>(nullptr, dummy_page_dict);
  CPDF_PageContentGenerator generator(pTestPage.Get());
  fxcrt::ostringstream buf;
  TestProcessPath(&generator, &buf, pPathObj.get());
  EXPECT_EQ(
      "q 1 0 0 1 0 0 cm 3.102 4.6700001 m 5.4499998 .28999999 l 4.2399998 "
      "3.1500001 4.6500001 2.98 3.4560001 .23999999 c 10.6000004 11.149999"
      "6 l 11 12.5 l 11.46 12.6700001 11.8400002 12.96 12 13.6400003 c h f"
      " Q\n",
      ByteString(buf));
}

TEST_F(CPDFPageContentGeneratorTest, ProcessGraphics) {
  auto pPathObj = std::make_unique<CPDF_PathObject>();
  pPathObj->set_stroke(true);
  pPathObj->set_filltype(CFX_FillRenderOptions::FillType::kWinding);
  pPathObj->path().AppendPoint(CFX_PointF(1, 2), CFX_Path::Point::Type::kMove);
  pPathObj->path().AppendPoint(CFX_PointF(3, 4), CFX_Path::Point::Type::kLine);
  pPathObj->path().AppendPointAndClose(CFX_PointF(5, 6),
                                       CFX_Path::Point::Type::kLine);

  static const std::vector<float> rgb = {0.5f, 0.7f, 0.35f};
  RetainPtr<CPDF_ColorSpace> pCS =
      CPDF_ColorSpace::GetStockCS(CPDF_ColorSpace::Family::kDeviceRGB);
  pPathObj->mutable_color_state().SetFillColor(pCS, rgb);

  static const std::vector<float> rgb2 = {1, 0.9f, 0};
  pPathObj->mutable_color_state().SetStrokeColor(pCS, rgb2);
  pPathObj->mutable_general_state().SetFillAlpha(0.5f);
  pPathObj->mutable_general_state().SetStrokeAlpha(0.8f);

  auto pDoc = std::make_unique<CPDF_TestDocument>();
  pDoc->CreateNewDoc();

  RetainPtr<CPDF_Dictionary> pPageDict(pDoc->CreateNewPage(0));
  auto pTestPage = pdfium::MakeRetain<CPDF_Page>(pDoc.get(), pPageDict);
  CPDF_PageContentGenerator generator(pTestPage.Get());
  fxcrt::ostringstream buf;
  TestProcessPath(&generator, &buf, pPathObj.get());
  ByteString path_string(buf);

  // Color RGB values used are integers divided by 255.
  EXPECT_EQ("q 0.501961 0.701961 0.34902 rg 1 0.901961 0 RG /",
            path_string.First(48));
  EXPECT_EQ(" gs 1 0 0 1 0 0 cm 1 2 m 3 4 l 5 6 l h B Q\n",
            path_string.Last(43));
  ASSERT_GT(path_string.GetLength(), 91U);
  RetainPtr<const CPDF_Dictionary> external_gs =
      TestGetResource(&generator, "ExtGState",
                      path_string.Substr(48, path_string.GetLength() - 91));
  ASSERT_TRUE(external_gs);
  EXPECT_EQ(0.5f, external_gs->GetFloatFor("ca"));
  EXPECT_EQ(0.8f, external_gs->GetFloatFor("CA"));

  // Same path, now with a stroke.
  pPathObj->mutable_graph_state().SetLineWidth(10.5f);
  buf.str("");
  TestProcessPath(&generator, &buf, pPathObj.get());
  ByteString path_string2(buf);
  EXPECT_EQ("q 0.501961 0.701961 0.34902 rg 1 0.901961 0 RG 10.5 w /",
            path_string2.First(55));
  EXPECT_EQ(" gs 1 0 0 1 0 0 cm 1 2 m 3 4 l 5 6 l h B Q\n",
            path_string2.Last(43));

  // Compare with the previous (should use same dictionary for gs)
  EXPECT_EQ(path_string.GetLength() + 7, path_string2.GetLength());
  EXPECT_EQ(path_string.Substr(48, path_string.GetLength() - 76),
            path_string2.Substr(55, path_string2.GetLength() - 83));
}

TEST_F(CPDFPageContentGeneratorTest, ProcessStandardText) {
  // Checking font whose font dictionary is not yet indirect object.
  auto pDoc = std::make_unique<CPDF_TestDocument>();
  pDoc->CreateNewDoc();

  RetainPtr<CPDF_Dictionary> pPageDict(pDoc->CreateNewPage(0));
  auto pTestPage = pdfium::MakeRetain<CPDF_Page>(pDoc.get(), pPageDict);
  CPDF_PageContentGenerator generator(pTestPage.Get());
  auto pTextObj = std::make_unique<CPDF_TextObject>();
  pTextObj->mutable_text_state().SetFont(
      CPDF_Font::GetStockFont(pDoc.get(), "Times-Roman"));
  pTextObj->mutable_text_state().SetFontSize(10.0f);

  static const std::vector<float> rgb = {0.5f, 0.7f, 0.35f};
  RetainPtr<CPDF_ColorSpace> pCS =
      CPDF_ColorSpace::GetStockCS(CPDF_ColorSpace::Family::kDeviceRGB);
  pTextObj->mutable_color_state().SetFillColor(pCS, rgb);

  static const std::vector<float> rgb2 = {1, 0.9f, 0};
  pTextObj->mutable_color_state().SetStrokeColor(pCS, rgb2);
  pTextObj->mutable_general_state().SetFillAlpha(0.5f);
  pTextObj->mutable_general_state().SetStrokeAlpha(0.8f);
  pTextObj->Transform(CFX_Matrix(1, 0, 0, 1, 100, 100));
  pTextObj->SetText("Hello World");
  fxcrt::ostringstream buf;
  TestProcessText(&generator, &buf, pTextObj.get());
  ByteString text_string(buf);
  auto first_resource_at = text_string.Find('/');
  ASSERT_TRUE(first_resource_at.has_value());
  first_resource_at = first_resource_at.value() + 1;
  auto second_resource_at = text_string.ReverseFind('/');
  ASSERT_TRUE(second_resource_at.has_value());
  second_resource_at = second_resource_at.value() + 1;
  ByteString first_string = text_string.First(first_resource_at.value());
  ByteString mid_string = text_string.Substr(
      first_resource_at.value(),
      second_resource_at.value() - first_resource_at.value());
  ByteString last_string =
      text_string.Last(text_string.GetLength() - second_resource_at.value());
  // q and Q must be outside the BT .. ET operations
  ByteString compare_string1 =
      "q 0.501961 0.701961 0.34902 rg 1 0.901961 0 RG /";
  // Color RGB values used are integers divided by 255.
  ByteString compare_string2 = " gs BT 1 0 0 1 100 100 Tm /";
  ByteString compare_string3 = " 10 Tf 0 Tr <48656C6C6F20576F726C64> Tj ET Q\n";
  EXPECT_LT(compare_string1.GetLength() + compare_string2.GetLength() +
                compare_string3.GetLength(),
            text_string.GetLength());
  EXPECT_EQ(compare_string1, first_string.First(compare_string1.GetLength()));
  EXPECT_EQ(compare_string2, mid_string.Last(compare_string2.GetLength()));
  EXPECT_EQ(compare_string3, last_string.Last(compare_string3.GetLength()));
  RetainPtr<const CPDF_Dictionary> external_gs = TestGetResource(
      &generator, "ExtGState",
      mid_string.First(mid_string.GetLength() - compare_string2.GetLength()));
  ASSERT_TRUE(external_gs);
  EXPECT_EQ(0.5f, external_gs->GetFloatFor("ca"));
  EXPECT_EQ(0.8f, external_gs->GetFloatFor("CA"));
  RetainPtr<const CPDF_Dictionary> font_dict = TestGetResource(
      &generator, "Font",
      last_string.First(last_string.GetLength() - compare_string3.GetLength()));
  ASSERT_TRUE(font_dict);
  EXPECT_EQ("Font", font_dict->GetNameFor("Type"));
  EXPECT_EQ("Type1", font_dict->GetNameFor("Subtype"));
  EXPECT_EQ("Times-Roman", font_dict->GetNameFor("BaseFont"));
}

TEST_F(CPDFPageContentGeneratorTest, ProcessText) {
  // Checking font whose font dictionary is already an indirect object.
  auto pDoc = std::make_unique<CPDF_TestDocument>();
  pDoc->CreateNewDoc();

  RetainPtr<CPDF_Dictionary> pPageDict(pDoc->CreateNewPage(0));
  auto pTestPage = pdfium::MakeRetain<CPDF_Page>(pDoc.get(), pPageDict);
  CPDF_PageContentGenerator generator(pTestPage.Get());

  fxcrt::ostringstream buf;
  {
    // Set the text object font and text
    auto pTextObj = std::make_unique<CPDF_TextObject>();
    auto pDict = pDoc->NewIndirect<CPDF_Dictionary>();
    pDict->SetNewFor<CPDF_Name>("Type", "Font");
    pDict->SetNewFor<CPDF_Name>("Subtype", "TrueType");

    RetainPtr<CPDF_Font> pFont = CPDF_Font::GetStockFont(pDoc.get(), "Arial");
    pDict->SetNewFor<CPDF_Name>("BaseFont", pFont->GetBaseFontName());

    auto pDesc = pDoc->NewIndirect<CPDF_Dictionary>();
    pDesc->SetNewFor<CPDF_Name>("Type", "FontDescriptor");
    pDesc->SetNewFor<CPDF_Name>("FontName", pFont->GetBaseFontName());
    pDict->SetNewFor<CPDF_Reference>("FontDescriptor", pDoc.get(),
                                     pDesc->GetObjNum());

    pTextObj->mutable_text_state().SetFont(
        CPDF_DocPageData::FromDocument(pDoc.get())->GetFont(pDict));
    pTextObj->mutable_text_state().SetFontSize(15.5f);
    pTextObj->SetText("I am indirect");
    pTextObj->SetTextRenderMode(TextRenderingMode::MODE_FILL_CLIP);

    // Add a clipping path.
    auto pPath = std::make_unique<CPDF_Path>();
    pPath->AppendPoint(CFX_PointF(0, 0), CFX_Path::Point::Type::kMove);
    pPath->AppendPoint(CFX_PointF(5, 0), CFX_Path::Point::Type::kLine);
    pPath->AppendPoint(CFX_PointF(5, 4), CFX_Path::Point::Type::kLine);
    pPath->AppendPointAndClose(CFX_PointF(0, 4), CFX_Path::Point::Type::kLine);
    CPDF_ClipPath& clip_path = pTextObj->mutable_clip_path();
    clip_path.Emplace();
    clip_path.AppendPath(*pPath, CFX_FillRenderOptions::FillType::kEvenOdd);

    TestProcessText(&generator, &buf, pTextObj.get());
  }

  ByteString text_string(buf);
  auto first_resource_at = text_string.Find('/');
  ASSERT_TRUE(first_resource_at.has_value());
  first_resource_at = first_resource_at.value() + 1;
  ByteString first_string = text_string.First(first_resource_at.value());
  ByteString last_string =
      text_string.Last(text_string.GetLength() - first_resource_at.value());
  // q and Q must be outside the BT .. ET operations
  ByteString compare_string1 = "q 0 0 5 4 re W* n BT 1 0 0 1 0 0 Tm /";
  ByteString compare_string2 =
      " 15.5 Tf 4 Tr <4920616D20696E646972656374> Tj ET Q\n";
  EXPECT_LT(compare_string1.GetLength() + compare_string2.GetLength(),
            text_string.GetLength());
  EXPECT_EQ(compare_string1, text_string.First(compare_string1.GetLength()));
  EXPECT_EQ(compare_string2, text_string.Last(compare_string2.GetLength()));
  RetainPtr<const CPDF_Dictionary> font_dict = TestGetResource(
      &generator, "Font",
      text_string.Substr(compare_string1.GetLength(),
                         text_string.GetLength() - compare_string1.GetLength() -
                             compare_string2.GetLength()));
  ASSERT_TRUE(font_dict);
  EXPECT_TRUE(font_dict->GetObjNum());
  EXPECT_EQ("Font", font_dict->GetNameFor("Type"));
  EXPECT_EQ("TrueType", font_dict->GetNameFor("Subtype"));
  EXPECT_EQ("Helvetica", font_dict->GetNameFor("BaseFont"));
  RetainPtr<const CPDF_Dictionary> font_desc =
      font_dict->GetDictFor("FontDescriptor");
  ASSERT_TRUE(font_desc);
  EXPECT_TRUE(font_desc->GetObjNum());
  EXPECT_EQ("FontDescriptor", font_desc->GetNameFor("Type"));
  EXPECT_EQ("Helvetica", font_desc->GetNameFor("FontName"));
}

TEST_F(CPDFPageContentGeneratorTest, ProcessEmptyForm) {
  auto pDoc = std::make_unique<CPDF_TestDocument>();
  pDoc->CreateNewDoc();
  auto pStream =
      pdfium::MakeRetain<CPDF_Stream>(pdfium::MakeRetain<CPDF_Dictionary>());

  // Create an empty form.
  auto pTestForm = std::make_unique<CPDF_Form>(pDoc.get(), nullptr, pStream);
  pTestForm->ParseContent();
  ASSERT_EQ(CPDF_PageObjectHolder::ParseState::kParsed,
            pTestForm->GetParseState());

  // The generated stream for the empty form should be an empty string.
  CPDF_PageContentGenerator generator(pTestForm.get());
  fxcrt::ostringstream buf;
  generator.ProcessPageObjects(&buf);
  EXPECT_EQ("", ByteString(buf));
}

TEST_F(CPDFPageContentGeneratorTest, ProcessFormWithPath) {
  auto pDoc = std::make_unique<CPDF_TestDocument>();
  pDoc->CreateNewDoc();
  static constexpr uint8_t kContents[] =
      "q 1 0 0 1 0 0 cm 3.102 4.6700001 m 5.4500012 .28999999 "
      "l 4.2399998 3.1499999 4.65 2.98 3.456 0.24 c 3.102 4.6700001 l h f Q\n";
  auto pStream = pdfium::MakeRetain<CPDF_Stream>(
      DataVector<uint8_t>(std::begin(kContents), std::end(kContents)),
      pdfium::MakeRetain<CPDF_Dictionary>());

  // Create a form with a non-empty stream.
  auto pTestForm = std::make_unique<CPDF_Form>(pDoc.get(), nullptr, pStream);
  pTestForm->ParseContent();
  ASSERT_EQ(CPDF_PageObjectHolder::ParseState::kParsed,
            pTestForm->GetParseState());

  CPDF_PageContentGenerator generator(pTestForm.get());
  fxcrt::ostringstream process_buf;
  generator.ProcessPageObjects(&process_buf);
  EXPECT_EQ(
      "q 1 0 0 1 0 0 cm 3.102 4.6700001 m 5.4500012 .28999999 l 4.2399998 3.14"
      "99999 4.6500001 2.98 3.4560001 .24000001 c 3.102 4.6700001 l h f Q\n",
      ByteString(process_buf));
}