// Copyright 2016 PDFium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "core/fpdfapi/parser/cpdf_document.h"

#include <memory>

#include "core/fpdfapi/cpdf_modulemgr.h"
#include "core/fpdfapi/parser/cpdf_array.h"
#include "core/fpdfapi/parser/cpdf_dictionary.h"
#include "core/fpdfapi/parser/cpdf_linearized_header.h"
#include "core/fpdfapi/parser/cpdf_parser.h"
#include "core/fxcrt/fx_memory.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace {

CPDF_Dictionary* CreatePageTreeNode(CPDF_Array* kids,
                                    CPDF_Document* pDoc,
                                    int count) {
  CPDF_Dictionary* pageNode = new CPDF_Dictionary();
  pageNode->SetStringFor("Type", "Pages");
  pageNode->SetReferenceFor("Kids", pDoc, pDoc->AddIndirectObject(kids));
  pageNode->SetIntegerFor("Count", count);
  uint32_t pageNodeRef = pDoc->AddIndirectObject(pageNode);
  for (size_t i = 0; i < kids->GetCount(); i++)
    kids->GetDictAt(i)->SetReferenceFor("Parent", pDoc, pageNodeRef);
  return pageNode;
}

CPDF_Dictionary* CreateNumberedPage(size_t number) {
  CPDF_Dictionary* page = new CPDF_Dictionary();
  page->SetStringFor("Type", "Page");
  page->SetIntegerFor("PageNumbering", number);
  return page;
}

class CPDF_TestDocumentForPages : public CPDF_Document {
 public:
  CPDF_TestDocumentForPages() : CPDF_Document(nullptr) {
    // Set up test
    CPDF_Array* zeroToTwo = new CPDF_Array();
    zeroToTwo->AddReference(this, AddIndirectObject(CreateNumberedPage(0)));
    zeroToTwo->AddReference(this, AddIndirectObject(CreateNumberedPage(1)));
    zeroToTwo->AddReference(this, AddIndirectObject(CreateNumberedPage(2)));
    CPDF_Dictionary* branch1 = CreatePageTreeNode(zeroToTwo, this, 3);

    CPDF_Array* zeroToThree = new CPDF_Array();
    zeroToThree->AddReference(this, branch1->GetObjNum());
    zeroToThree->AddReference(this, AddIndirectObject(CreateNumberedPage(3)));
    CPDF_Dictionary* branch2 = CreatePageTreeNode(zeroToThree, this, 4);

    CPDF_Array* fourFive = new CPDF_Array();
    fourFive->AddReference(this, AddIndirectObject(CreateNumberedPage(4)));
    fourFive->AddReference(this, AddIndirectObject(CreateNumberedPage(5)));
    CPDF_Dictionary* branch3 = CreatePageTreeNode(fourFive, this, 2);

    CPDF_Array* justSix = new CPDF_Array();
    justSix->AddReference(this, AddIndirectObject(CreateNumberedPage(6)));
    CPDF_Dictionary* branch4 = CreatePageTreeNode(justSix, this, 1);

    CPDF_Array* allPages = new CPDF_Array();
    allPages->AddReference(this, branch2->GetObjNum());
    allPages->AddReference(this, branch3->GetObjNum());
    allPages->AddReference(this, branch4->GetObjNum());
    CPDF_Dictionary* pagesDict = CreatePageTreeNode(allPages, this, 7);

    m_pOwnedRootDict.reset(new CPDF_Dictionary());
    m_pOwnedRootDict->SetReferenceFor("Pages", this, pagesDict->GetObjNum());
    m_pRootDict = m_pOwnedRootDict.get();
    m_PageList.SetSize(7);
  }

 private:
  std::unique_ptr<CPDF_Dictionary> m_pOwnedRootDict;
};

class CPDF_TestDocumentWithPageWithoutPageNum : public CPDF_Document {
 public:
  CPDF_TestDocumentWithPageWithoutPageNum() : CPDF_Document(nullptr) {
    // Set up test
    CPDF_Array* allPages = new CPDF_Array();
    allPages->AddReference(this, AddIndirectObject(CreateNumberedPage(0)));
    allPages->AddReference(this, AddIndirectObject(CreateNumberedPage(1)));
    // Page without pageNum.
    allPages->Add(CreateNumberedPage(2));
    CPDF_Dictionary* pagesDict = CreatePageTreeNode(allPages, this, 3);

    m_pOwnedRootDict.reset(new CPDF_Dictionary());
    m_pOwnedRootDict->SetReferenceFor("Pages", this, pagesDict->GetObjNum());
    m_pRootDict = m_pOwnedRootDict.get();
    m_PageList.SetSize(3);
  }

 private:
  std::unique_ptr<CPDF_Dictionary> m_pOwnedRootDict;
};

class TestLinearized : public CPDF_LinearizedHeader {
 public:
  explicit TestLinearized(CPDF_Dictionary* dict)
      : CPDF_LinearizedHeader(dict) {}
};
}  // namespace

class cpdf_document_test : public testing::Test {
 public:
  void SetUp() override {
    CPDF_ModuleMgr* module_mgr = CPDF_ModuleMgr::Get();
    module_mgr->InitPageModule();
  }
  void TearDown() override {}
};

TEST_F(cpdf_document_test, GetPages) {
  std::unique_ptr<CPDF_TestDocumentForPages> document =
      pdfium::MakeUnique<CPDF_TestDocumentForPages>();
  for (int i = 0; i < 7; i++) {
    CPDF_Dictionary* page = document->GetPage(i);
    ASSERT_TRUE(page);
    ASSERT_TRUE(page->KeyExist("PageNumbering"));
    EXPECT_EQ(i, page->GetIntegerFor("PageNumbering"));
  }
  CPDF_Dictionary* page = document->GetPage(7);
  EXPECT_FALSE(page);
}

TEST_F(cpdf_document_test, GetPageWithoutObjNumTwice) {
  std::unique_ptr<CPDF_TestDocumentWithPageWithoutPageNum> document =
      pdfium::MakeUnique<CPDF_TestDocumentWithPageWithoutPageNum>();
  const CPDF_Dictionary* page = document->GetPage(2);
  ASSERT_TRUE(page);
  // This is page without obj num.
  ASSERT_EQ(0ul, page->GetObjNum());
  const CPDF_Dictionary* second_call_page = document->GetPage(2);
  EXPECT_TRUE(second_call_page);
  EXPECT_EQ(page, second_call_page);
}

TEST_F(cpdf_document_test, GetPagesReverseOrder) {
  std::unique_ptr<CPDF_TestDocumentForPages> document =
      pdfium::MakeUnique<CPDF_TestDocumentForPages>();
  for (int i = 6; i >= 0; i--) {
    CPDF_Dictionary* page = document->GetPage(i);
    ASSERT_TRUE(page);
    ASSERT_TRUE(page->KeyExist("PageNumbering"));
    EXPECT_EQ(i, page->GetIntegerFor("PageNumbering"));
  }
  CPDF_Dictionary* page = document->GetPage(7);
  EXPECT_FALSE(page);
}

TEST(cpdf_document, GetPagesInDisorder) {
  std::unique_ptr<CPDF_TestDocumentForPages> document =
      pdfium::MakeUnique<CPDF_TestDocumentForPages>();

  CPDF_Dictionary* page = document->GetPage(1);
  ASSERT_TRUE(page);
  ASSERT_TRUE(page->KeyExist("PageNumbering"));
  EXPECT_EQ(1, page->GetIntegerFor("PageNumbering"));

  page = document->GetPage(3);
  ASSERT_TRUE(page);
  ASSERT_TRUE(page->KeyExist("PageNumbering"));
  EXPECT_EQ(3, page->GetIntegerFor("PageNumbering"));

  page = document->GetPage(7);
  EXPECT_FALSE(page);

  page = document->GetPage(6);
  ASSERT_TRUE(page);
  ASSERT_TRUE(page->KeyExist("PageNumbering"));
  EXPECT_EQ(6, page->GetIntegerFor("PageNumbering"));
}

TEST_F(cpdf_document_test, UseCachedPageObjNumIfHaveNotPagesDict) {
  // ObjNum can be added in CPDF_DataAvail::IsPageAvail, and PagesDict
  // can be not exists in this case.
  // (case, when hint table is used to page check in CPDF_DataAvail).
  CPDF_Document document(pdfium::MakeUnique<CPDF_Parser>());
  auto dict = pdfium::MakeUnique<CPDF_Dictionary>();
  dict->SetBooleanFor("Linearized", true);
  const int page_count = 100;
  dict->SetIntegerFor("N", page_count);
  TestLinearized linearized(dict.get());
  document.LoadLinearizedDoc(&linearized);
  ASSERT_EQ(page_count, document.GetPageCount());
  CPDF_Object* page_stub = new CPDF_Dictionary();
  const uint32_t obj_num = document.AddIndirectObject(page_stub);
  const int test_page_num = 33;

  EXPECT_FALSE(document.IsPageLoaded(test_page_num));
  EXPECT_EQ(nullptr, document.GetPage(test_page_num));

  document.SetPageObjNum(test_page_num, obj_num);

  EXPECT_TRUE(document.IsPageLoaded(test_page_num));
  EXPECT_EQ(page_stub, document.GetPage(test_page_num));
}