// Copyright 2014 The PDFium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com

#include "core/fpdfapi/edit/cpdf_creator.h"

#include <stdint.h>

#include <algorithm>
#include <set>
#include <utility>

#include "core/fpdfapi/parser/cpdf_array.h"
#include "core/fpdfapi/parser/cpdf_crypto_handler.h"
#include "core/fpdfapi/parser/cpdf_dictionary.h"
#include "core/fpdfapi/parser/cpdf_document.h"
#include "core/fpdfapi/parser/cpdf_encryptor.h"
#include "core/fpdfapi/parser/cpdf_flateencoder.h"
#include "core/fpdfapi/parser/cpdf_number.h"
#include "core/fpdfapi/parser/cpdf_parser.h"
#include "core/fpdfapi/parser/cpdf_security_handler.h"
#include "core/fpdfapi/parser/cpdf_string.h"
#include "core/fpdfapi/parser/fpdf_parser_utility.h"
#include "core/fpdfapi/parser/object_tree_traversal_util.h"
#include "core/fxcrt/data_vector.h"
#include "core/fxcrt/fx_extension.h"
#include "core/fxcrt/fx_random.h"
#include "core/fxcrt/fx_safe_types.h"
#include "core/fxcrt/span_util.h"
#include "core/fxcrt/stl_util.h"
#include "third_party/base/check.h"
#include "third_party/base/containers/contains.h"

namespace {

const size_t kArchiveBufferSize = 32768;

class CFX_FileBufferArchive final : public IFX_ArchiveStream {
 public:
  explicit CFX_FileBufferArchive(RetainPtr<IFX_RetainableWriteStream> file);
  ~CFX_FileBufferArchive() override;

  bool WriteBlock(pdfium::span<const uint8_t> buffer) override;
  FX_FILESIZE CurrentOffset() const override { return offset_; }

 private:
  bool Flush();

  FX_FILESIZE offset_ = 0;
  DataVector<uint8_t> buffer_;
  pdfium::span<uint8_t> available_;
  RetainPtr<IFX_RetainableWriteStream> const backing_file_;
};

CFX_FileBufferArchive::CFX_FileBufferArchive(
    RetainPtr<IFX_RetainableWriteStream> file)
    : buffer_(kArchiveBufferSize),
      available_(buffer_),
      backing_file_(std::move(file)) {
  DCHECK(backing_file_);
}

CFX_FileBufferArchive::~CFX_FileBufferArchive() {
  Flush();
}

bool CFX_FileBufferArchive::Flush() {
  size_t nUsed = buffer_.size() - available_.size();
  available_ = pdfium::make_span(buffer_);
  if (!nUsed)
    return true;
  return backing_file_->WriteBlock(available_.first(nUsed));
}

bool CFX_FileBufferArchive::WriteBlock(pdfium::span<const uint8_t> buffer) {
  if (buffer.empty())
    return true;

  pdfium::span<const uint8_t> src_span = buffer;
  while (!src_span.empty()) {
    size_t copy_size = std::min(available_.size(), src_span.size());
    fxcrt::spancpy(available_, src_span.first(copy_size));
    src_span = src_span.subspan(copy_size);
    available_ = available_.subspan(copy_size);
    if (available_.empty() && !Flush())
      return false;
  }

  FX_SAFE_FILESIZE safe_offset = offset_;
  safe_offset += buffer.size();
  if (!safe_offset.IsValid())
    return false;

  offset_ = safe_offset.ValueOrDie();
  return true;
}

ByteString GenerateFileID(uint32_t dwSeed1, uint32_t dwSeed2) {
  uint32_t buffer[4];
  void* pContext1 = FX_Random_MT_Start(dwSeed1);
  void* pContext2 = FX_Random_MT_Start(dwSeed2);
  buffer[0] = FX_Random_MT_Generate(pContext1);
  buffer[1] = FX_Random_MT_Generate(pContext1);
  buffer[2] = FX_Random_MT_Generate(pContext2);
  buffer[3] = FX_Random_MT_Generate(pContext2);
  FX_Random_MT_Close(pContext1);
  FX_Random_MT_Close(pContext2);
  return ByteString(pdfium::as_bytes<uint32_t>(buffer));
}

bool OutputIndex(IFX_ArchiveStream* archive, FX_FILESIZE offset) {
  return archive->WriteByte(static_cast<uint8_t>(offset >> 24)) &&
         archive->WriteByte(static_cast<uint8_t>(offset >> 16)) &&
         archive->WriteByte(static_cast<uint8_t>(offset >> 8)) &&
         archive->WriteByte(static_cast<uint8_t>(offset)) &&
         archive->WriteByte(0);
}

}  // namespace

CPDF_Creator::CPDF_Creator(CPDF_Document* pDoc,
                           RetainPtr<IFX_RetainableWriteStream> archive)
    : m_pDocument(pDoc),
      m_pParser(pDoc->GetParser()),
      m_pEncryptDict(m_pParser ? m_pParser->GetEncryptDict() : nullptr),
      m_pSecurityHandler(m_pParser ? m_pParser->GetSecurityHandler() : nullptr),
      m_dwLastObjNum(m_pDocument->GetLastObjNum()),
      m_Archive(std::make_unique<CFX_FileBufferArchive>(std::move(archive))) {}

CPDF_Creator::~CPDF_Creator() = default;

bool CPDF_Creator::WriteIndirectObj(uint32_t objnum, const CPDF_Object* pObj) {
  if (!m_Archive->WriteDWord(objnum) || !m_Archive->WriteString(" 0 obj\r\n"))
    return false;

  std::unique_ptr<CPDF_Encryptor> encryptor;
  if (GetCryptoHandler() && pObj != m_pEncryptDict)
    encryptor = std::make_unique<CPDF_Encryptor>(GetCryptoHandler(), objnum);

  if (!pObj->WriteTo(m_Archive.get(), encryptor.get()))
    return false;

  return m_Archive->WriteString("\r\nendobj\r\n");
}

bool CPDF_Creator::WriteOldIndirectObject(uint32_t objnum) {
  if (m_pParser->IsObjectFreeOrNull(objnum))
    return true;

  m_ObjectOffsets[objnum] = m_Archive->CurrentOffset();

  bool bExistInMap = !!m_pDocument->GetIndirectObject(objnum);
  RetainPtr<CPDF_Object> pObj = m_pDocument->GetOrParseIndirectObject(objnum);
  if (!pObj) {
    m_ObjectOffsets.erase(objnum);
    return true;
  }
  if (!WriteIndirectObj(pObj->GetObjNum(), pObj.Get()))
    return false;
  if (!bExistInMap)
    m_pDocument->DeleteIndirectObject(objnum);
  return true;
}

bool CPDF_Creator::WriteOldObjs() {
  const uint32_t nLastObjNum = m_pParser->GetLastObjNum();
  if (!m_pParser->IsValidObjectNumber(nLastObjNum)) {
    return true;
  }
  if (m_CurObjNum > nLastObjNum) {
    return true;
  }

  const std::set<uint32_t> objects_with_refs =
      GetObjectsWithReferences(m_pDocument);
  uint32_t last_object_number_written = 0;
  for (uint32_t objnum = m_CurObjNum; objnum <= nLastObjNum; ++objnum) {
    if (!pdfium::Contains(objects_with_refs, objnum)) {
      continue;
    }
    if (!WriteOldIndirectObject(objnum)) {
      return false;
    }
    last_object_number_written = objnum;
  }
  // If there are no new objects to write, then adjust `m_dwLastObjNum` if
  // needed to reflect the actual last object number.
  if (m_NewObjNumArray.empty()) {
    m_dwLastObjNum = last_object_number_written;
  }
  return true;
}

bool CPDF_Creator::WriteNewObjs() {
  for (size_t i = m_CurObjNum; i < m_NewObjNumArray.size(); ++i) {
    uint32_t objnum = m_NewObjNumArray[i];
    RetainPtr<const CPDF_Object> pObj = m_pDocument->GetIndirectObject(objnum);
    if (!pObj)
      continue;

    m_ObjectOffsets[objnum] = m_Archive->CurrentOffset();
    if (!WriteIndirectObj(pObj->GetObjNum(), pObj.Get()))
      return false;
  }
  return true;
}

void CPDF_Creator::InitNewObjNumOffsets() {
  for (const auto& pair : *m_pDocument) {
    const uint32_t objnum = pair.first;
    if (m_IsIncremental ||
        pair.second->GetObjNum() == CPDF_Object::kInvalidObjNum) {
      continue;
    }
    if (m_pParser && m_pParser->IsValidObjectNumber(objnum) &&
        !m_pParser->IsObjectFree(objnum)) {
      continue;
    }
    m_NewObjNumArray.insert(std::lower_bound(m_NewObjNumArray.begin(),
                                             m_NewObjNumArray.end(), objnum),
                            objnum);
  }
}

CPDF_Creator::Stage CPDF_Creator::WriteDoc_Stage1() {
  DCHECK(m_iStage > Stage::kInvalid || m_iStage < Stage::kInitWriteObjs20);
  if (m_iStage == Stage::kInit0) {
    if (!m_pParser || (m_bSecurityChanged && m_IsOriginal))
      m_IsIncremental = false;

    m_iStage = Stage::kWriteHeader10;
  }
  if (m_iStage == Stage::kWriteHeader10) {
    if (!m_IsIncremental) {
      if (!m_Archive->WriteString("%PDF-1."))
        return Stage::kInvalid;

      int32_t version = 7;
      if (m_FileVersion)
        version = m_FileVersion;
      else if (m_pParser)
        version = m_pParser->GetFileVersion();

      if (!m_Archive->WriteDWord(version % 10) ||
          !m_Archive->WriteString("\r\n%\xA1\xB3\xC5\xD7\r\n")) {
        return Stage::kInvalid;
      }
      m_iStage = Stage::kInitWriteObjs20;
    } else {
      m_SavedOffset = m_pParser->GetDocumentSize();
      m_iStage = Stage::kWriteIncremental15;
    }
  }
  if (m_iStage == Stage::kWriteIncremental15) {
    if (m_IsOriginal && m_SavedOffset > 0) {
      if (!m_pParser->WriteToArchive(m_Archive.get(), m_SavedOffset))
        return Stage::kInvalid;
    }
    if (m_IsOriginal && m_pParser->GetLastXRefOffset() == 0) {
      for (uint32_t num = 0; num <= m_pParser->GetLastObjNum(); ++num) {
        if (m_pParser->IsObjectFreeOrNull(num))
          continue;

        m_ObjectOffsets[num] = m_pParser->GetObjectPositionOrZero(num);
      }
    }
    m_iStage = Stage::kInitWriteObjs20;
  }
  InitNewObjNumOffsets();
  return m_iStage;
}

CPDF_Creator::Stage CPDF_Creator::WriteDoc_Stage2() {
  DCHECK(m_iStage >= Stage::kInitWriteObjs20 ||
         m_iStage < Stage::kInitWriteXRefs80);
  if (m_iStage == Stage::kInitWriteObjs20) {
    if (!m_IsIncremental && m_pParser) {
      m_CurObjNum = 0;
      m_iStage = Stage::kWriteOldObjs21;
    } else {
      m_iStage = Stage::kInitWriteNewObjs25;
    }
  }
  if (m_iStage == Stage::kWriteOldObjs21) {
    if (!WriteOldObjs())
      return Stage::kInvalid;

    m_iStage = Stage::kInitWriteNewObjs25;
  }
  if (m_iStage == Stage::kInitWriteNewObjs25) {
    m_CurObjNum = 0;
    m_iStage = Stage::kWriteNewObjs26;
  }
  if (m_iStage == Stage::kWriteNewObjs26) {
    if (!WriteNewObjs())
      return Stage::kInvalid;

    m_iStage = Stage::kWriteEncryptDict27;
  }
  if (m_iStage == Stage::kWriteEncryptDict27) {
    if (m_pEncryptDict && m_pEncryptDict->IsInline()) {
      m_dwLastObjNum += 1;
      FX_FILESIZE saveOffset = m_Archive->CurrentOffset();
      if (!WriteIndirectObj(m_dwLastObjNum, m_pEncryptDict.Get()))
        return Stage::kInvalid;

      m_ObjectOffsets[m_dwLastObjNum] = saveOffset;
      if (m_IsIncremental)
        m_NewObjNumArray.push_back(m_dwLastObjNum);
    }
    m_iStage = Stage::kInitWriteXRefs80;
  }
  return m_iStage;
}

CPDF_Creator::Stage CPDF_Creator::WriteDoc_Stage3() {
  DCHECK(m_iStage >= Stage::kInitWriteXRefs80 ||
         m_iStage < Stage::kWriteTrailerAndFinish90);

  uint32_t dwLastObjNum = m_dwLastObjNum;
  if (m_iStage == Stage::kInitWriteXRefs80) {
    m_XrefStart = m_Archive->CurrentOffset();
    if (!m_IsIncremental || !m_pParser->IsXRefStream()) {
      if (!m_IsIncremental || m_pParser->GetLastXRefOffset() == 0) {
        ByteString str;
        str = pdfium::Contains(m_ObjectOffsets, 1)
                  ? "xref\r\n"
                  : "xref\r\n0 1\r\n0000000000 65535 f\r\n";
        if (!m_Archive->WriteString(str.AsStringView()))
          return Stage::kInvalid;

        m_CurObjNum = 1;
        m_iStage = Stage::kWriteXrefsNotIncremental81;
      } else {
        if (!m_Archive->WriteString("xref\r\n"))
          return Stage::kInvalid;

        m_CurObjNum = 0;
        m_iStage = Stage::kWriteXrefsIncremental82;
      }
    } else {
      m_iStage = Stage::kWriteTrailerAndFinish90;
    }
  }
  if (m_iStage == Stage::kWriteXrefsNotIncremental81) {
    ByteString str;
    uint32_t i = m_CurObjNum;
    uint32_t j;
    while (i <= dwLastObjNum) {
      while (i <= dwLastObjNum && !pdfium::Contains(m_ObjectOffsets, i))
        i++;

      if (i > dwLastObjNum)
        break;

      j = i;
      while (j <= dwLastObjNum && pdfium::Contains(m_ObjectOffsets, j))
        j++;

      if (i == 1)
        str = ByteString::Format("0 %d\r\n0000000000 65535 f\r\n", j);
      else
        str = ByteString::Format("%d %d\r\n", i, j - i);

      if (!m_Archive->WriteString(str.AsStringView()))
        return Stage::kInvalid;

      while (i < j) {
        str = ByteString::Format("%010d 00000 n\r\n", m_ObjectOffsets[i++]);
        if (!m_Archive->WriteString(str.AsStringView()))
          return Stage::kInvalid;
      }
      if (i > dwLastObjNum)
        break;
    }
    m_iStage = Stage::kWriteTrailerAndFinish90;
  }
  if (m_iStage == Stage::kWriteXrefsIncremental82) {
    ByteString str;
    uint32_t iCount = fxcrt::CollectionSize<uint32_t>(m_NewObjNumArray);
    uint32_t i = m_CurObjNum;
    while (i < iCount) {
      size_t j = i;
      uint32_t objnum = m_NewObjNumArray[i];
      while (j < iCount) {
        if (++j == iCount)
          break;
        uint32_t dwCurrent = m_NewObjNumArray[j];
        if (dwCurrent - objnum > 1)
          break;
        objnum = dwCurrent;
      }
      objnum = m_NewObjNumArray[i];
      if (objnum == 1)
        str = ByteString::Format("0 %d\r\n0000000000 65535 f\r\n", j - i + 1);
      else
        str = ByteString::Format("%d %d\r\n", objnum, j - i);

      if (!m_Archive->WriteString(str.AsStringView()))
        return Stage::kInvalid;

      while (i < j) {
        objnum = m_NewObjNumArray[i++];
        str = ByteString::Format("%010d 00000 n\r\n", m_ObjectOffsets[objnum]);
        if (!m_Archive->WriteString(str.AsStringView()))
          return Stage::kInvalid;
      }
    }
    m_iStage = Stage::kWriteTrailerAndFinish90;
  }
  return m_iStage;
}

CPDF_Creator::Stage CPDF_Creator::WriteDoc_Stage4() {
  DCHECK(m_iStage >= Stage::kWriteTrailerAndFinish90);

  bool bXRefStream = m_IsIncremental && m_pParser->IsXRefStream();
  if (!bXRefStream) {
    if (!m_Archive->WriteString("trailer\r\n<<"))
      return Stage::kInvalid;
  } else {
    if (!m_Archive->WriteDWord(m_pDocument->GetLastObjNum() + 1) ||
        !m_Archive->WriteString(" 0 obj <<")) {
      return Stage::kInvalid;
    }
  }

  if (m_pParser) {
    CPDF_DictionaryLocker locker(m_pParser->GetCombinedTrailer());
    for (const auto& it : locker) {
      const ByteString& key = it.first;
      const RetainPtr<CPDF_Object>& pValue = it.second;
      if (key == "Encrypt" || key == "Size" || key == "Filter" ||
          key == "Index" || key == "Length" || key == "Prev" || key == "W" ||
          key == "XRefStm" || key == "ID" || key == "DecodeParms" ||
          key == "Type") {
        continue;
      }
      if (!m_Archive->WriteString(("/")) ||
          !m_Archive->WriteString(PDF_NameEncode(key).AsStringView())) {
        return Stage::kInvalid;
      }
      if (!pValue->WriteTo(m_Archive.get(), nullptr))
        return Stage::kInvalid;
    }
  } else {
    if (!m_Archive->WriteString("\r\n/Root ") ||
        !m_Archive->WriteDWord(m_pDocument->GetRoot()->GetObjNum()) ||
        !m_Archive->WriteString(" 0 R\r\n")) {
      return Stage::kInvalid;
    }
    if (m_pDocument->GetInfo()) {
      if (!m_Archive->WriteString("/Info ") ||
          !m_Archive->WriteDWord(m_pDocument->GetInfo()->GetObjNum()) ||
          !m_Archive->WriteString(" 0 R\r\n")) {
        return Stage::kInvalid;
      }
    }
  }
  if (m_pEncryptDict) {
    if (!m_Archive->WriteString("/Encrypt"))
      return Stage::kInvalid;

    uint32_t dwObjNum = m_pEncryptDict->GetObjNum();
    if (dwObjNum == 0)
      dwObjNum = m_pDocument->GetLastObjNum() + 1;
    if (!m_Archive->WriteString(" ") || !m_Archive->WriteDWord(dwObjNum) ||
        !m_Archive->WriteString(" 0 R ")) {
      return Stage::kInvalid;
    }
  }

  if (!m_Archive->WriteString("/Size ") ||
      !m_Archive->WriteDWord(m_dwLastObjNum + (bXRefStream ? 2 : 1))) {
    return Stage::kInvalid;
  }
  if (m_IsIncremental) {
    FX_FILESIZE prev = m_pParser->GetLastXRefOffset();
    if (prev) {
      if (!m_Archive->WriteString("/Prev ") || !m_Archive->WriteFilesize(prev))
        return Stage::kInvalid;
    }
  }
  if (m_pIDArray) {
    if (!m_Archive->WriteString(("/ID")) ||
        !m_pIDArray->WriteTo(m_Archive.get(), nullptr)) {
      return Stage::kInvalid;
    }
  }
  if (!bXRefStream) {
    if (!m_Archive->WriteString(">>"))
      return Stage::kInvalid;
  } else {
    if (!m_Archive->WriteString("/W[0 4 1]/Index["))
      return Stage::kInvalid;
    if (m_IsIncremental && m_pParser && m_pParser->GetLastXRefOffset() == 0) {
      uint32_t i = 0;
      for (i = 0; i < m_dwLastObjNum; i++) {
        if (!pdfium::Contains(m_ObjectOffsets, i))
          continue;
        if (!m_Archive->WriteDWord(i) || !m_Archive->WriteString(" 1 "))
          return Stage::kInvalid;
      }
      if (!m_Archive->WriteString("]/Length ") ||
          !m_Archive->WriteDWord(m_dwLastObjNum * 5) ||
          !m_Archive->WriteString(">>stream\r\n")) {
        return Stage::kInvalid;
      }
      for (i = 0; i < m_dwLastObjNum; i++) {
        auto it = m_ObjectOffsets.find(i);
        if (it == m_ObjectOffsets.end())
          continue;
        if (!OutputIndex(m_Archive.get(), it->second))
          return Stage::kInvalid;
      }
    } else {
      int count = fxcrt::CollectionSize<int>(m_NewObjNumArray);
      int i = 0;
      for (i = 0; i < count; i++) {
        if (!m_Archive->WriteDWord(m_NewObjNumArray[i]) ||
            !m_Archive->WriteString(" 1 ")) {
          return Stage::kInvalid;
        }
      }
      if (!m_Archive->WriteString("]/Length ") ||
          !m_Archive->WriteDWord(count * 5) ||
          !m_Archive->WriteString(">>stream\r\n")) {
        return Stage::kInvalid;
      }
      for (i = 0; i < count; ++i) {
        if (!OutputIndex(m_Archive.get(), m_ObjectOffsets[m_NewObjNumArray[i]]))
          return Stage::kInvalid;
      }
    }
    if (!m_Archive->WriteString("\r\nendstream"))
      return Stage::kInvalid;
  }

  if (!m_Archive->WriteString("\r\nstartxref\r\n") ||
      !m_Archive->WriteFilesize(m_XrefStart) ||
      !m_Archive->WriteString("\r\n%%EOF\r\n")) {
    return Stage::kInvalid;
  }

  m_iStage = Stage::kComplete100;
  return m_iStage;
}

bool CPDF_Creator::Create(uint32_t flags) {
  m_IsIncremental = !!(flags & FPDFCREATE_INCREMENTAL);
  m_IsOriginal = !(flags & FPDFCREATE_NO_ORIGINAL);

  m_iStage = Stage::kInit0;
  m_dwLastObjNum = m_pDocument->GetLastObjNum();
  m_ObjectOffsets.clear();
  m_NewObjNumArray.clear();

  InitID();
  return Continue();
}

void CPDF_Creator::InitID() {
  DCHECK(!m_pIDArray);

  m_pIDArray = pdfium::MakeRetain<CPDF_Array>();
  RetainPtr<const CPDF_Array> pOldIDArray =
      m_pParser ? m_pParser->GetIDArray() : nullptr;
  RetainPtr<const CPDF_Object> pID1 =
      pOldIDArray ? pOldIDArray->GetObjectAt(0) : nullptr;
  if (pID1) {
    m_pIDArray->Append(pID1->Clone());
  } else {
    ByteString bsBuffer =
        GenerateFileID((uint32_t)(uintptr_t)this, m_dwLastObjNum);
    m_pIDArray->AppendNew<CPDF_String>(bsBuffer, true);
  }

  if (pOldIDArray) {
    RetainPtr<const CPDF_Object> pID2 = pOldIDArray->GetObjectAt(1);
    if (m_IsIncremental && m_pEncryptDict && pID2) {
      m_pIDArray->Append(pID2->Clone());
      return;
    }
    ByteString bsBuffer =
        GenerateFileID((uint32_t)(uintptr_t)this, m_dwLastObjNum);
    m_pIDArray->AppendNew<CPDF_String>(bsBuffer, true);
    return;
  }

  m_pIDArray->Append(m_pIDArray->GetObjectAt(0)->Clone());
  if (m_pEncryptDict) {
    DCHECK(m_pParser);
    int revision = m_pEncryptDict->GetIntegerFor("R");
    if ((revision == 2 || revision == 3) &&
        m_pEncryptDict->GetByteStringFor("Filter") == "Standard") {
      m_pNewEncryptDict = ToDictionary(m_pEncryptDict->Clone());
      m_pEncryptDict = m_pNewEncryptDict;
      m_pSecurityHandler = pdfium::MakeRetain<CPDF_SecurityHandler>();
      m_pSecurityHandler->OnCreate(m_pNewEncryptDict.Get(), m_pIDArray.Get(),
                                   m_pParser->GetEncodedPassword());
      m_bSecurityChanged = true;
    }
  }
}

bool CPDF_Creator::Continue() {
  if (m_iStage < Stage::kInit0)
    return false;

  Stage iRet = Stage::kInit0;
  while (m_iStage < Stage::kComplete100) {
    if (m_iStage < Stage::kInitWriteObjs20)
      iRet = WriteDoc_Stage1();
    else if (m_iStage < Stage::kInitWriteXRefs80)
      iRet = WriteDoc_Stage2();
    else if (m_iStage < Stage::kWriteTrailerAndFinish90)
      iRet = WriteDoc_Stage3();
    else
      iRet = WriteDoc_Stage4();

    if (iRet < m_iStage)
      break;
  }

  if (iRet <= Stage::kInit0 || m_iStage == Stage::kComplete100) {
    m_iStage = Stage::kInvalid;
    return iRet > Stage::kInit0;
  }

  return m_iStage > Stage::kInvalid;
}

bool CPDF_Creator::SetFileVersion(int32_t fileVersion) {
  if (fileVersion < 10 || fileVersion > 17)
    return false;
  m_FileVersion = fileVersion;
  return true;
}

void CPDF_Creator::RemoveSecurity() {
  m_pSecurityHandler.Reset();
  m_bSecurityChanged = true;
  m_pEncryptDict = nullptr;
  m_pNewEncryptDict.Reset();
}

CPDF_CryptoHandler* CPDF_Creator::GetCryptoHandler() {
  return m_pSecurityHandler ? m_pSecurityHandler->GetCryptoHandler() : nullptr;
}