// 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 "public/fpdf_save.h"

#include <optional>
#include <utility>
#include <vector>

#include "build/build_config.h"
#include "core/fpdfapi/edit/cpdf_creator.h"
#include "core/fpdfapi/parser/cpdf_array.h"
#include "core/fpdfapi/parser/cpdf_dictionary.h"
#include "core/fpdfapi/parser/cpdf_document.h"
#include "core/fpdfapi/parser/cpdf_reference.h"
#include "core/fpdfapi/parser/cpdf_stream_acc.h"
#include "core/fpdfapi/parser/cpdf_string.h"
#include "core/fxcrt/fx_extension.h"
#include "core/fxcrt/stl_util.h"
#include "fpdfsdk/cpdfsdk_filewriteadapter.h"
#include "fpdfsdk/cpdfsdk_helpers.h"
#include "public/fpdf_edit.h"

#ifdef PDF_ENABLE_XFA
#include "core/fpdfapi/parser/cpdf_stream.h"
#include "core/fxcrt/cfx_memorystream.h"
#include "fpdfsdk/fpdfxfa/cpdfxfa_context.h"
#include "public/fpdf_formfill.h"
#endif

namespace {

#ifdef PDF_ENABLE_XFA
bool SaveXFADocumentData(CPDFXFA_Context* context,
                         std::vector<RetainPtr<IFX_SeekableStream>>* fileList) {
  if (!context) {
    return false;
  }

  if (!context->ContainsExtensionForm()) {
    return true;
  }

  CPDF_Document* pPDFDocument = context->GetPDFDoc();
  if (!pPDFDocument) {
    return false;
  }

  RetainPtr<CPDF_Dictionary> pRoot = pPDFDocument->GetMutableRoot();
  if (!pRoot) {
    return false;
  }

  RetainPtr<CPDF_Dictionary> pAcroForm = pRoot->GetMutableDictFor("AcroForm");
  if (!pAcroForm) {
    return false;
  }

  RetainPtr<CPDF_Object> pXFA = pAcroForm->GetMutableObjectFor("XFA");
  if (!pXFA) {
    return true;
  }

  CPDF_Array* pArray = pXFA->AsMutableArray();
  if (!pArray) {
    return false;
  }

  int size = fxcrt::CollectionSize<int>(*pArray);
  int iFormIndex = -1;
  int iDataSetsIndex = -1;
  for (int i = 0; i < size - 1; i++) {
    RetainPtr<const CPDF_Object> pPDFObj = pArray->GetObjectAt(i);
    if (!pPDFObj->IsString()) {
      continue;
    }
    if (pPDFObj->GetString() == "form") {
      iFormIndex = i + 1;
    } else if (pPDFObj->GetString() == "datasets") {
      iDataSetsIndex = i + 1;
    }
  }

  RetainPtr<CPDF_Stream> pFormStream;
  if (iFormIndex != -1) {
    // Get form CPDF_Stream
    RetainPtr<CPDF_Object> pFormPDFObj = pArray->GetMutableObjectAt(iFormIndex);
    if (pFormPDFObj->IsReference()) {
      RetainPtr<CPDF_Object> pFormDirectObj = pFormPDFObj->GetMutableDirect();
      if (pFormDirectObj && pFormDirectObj->IsStream()) {
        pFormStream.Reset(pFormDirectObj->AsMutableStream());
      }
    } else if (pFormPDFObj->IsStream()) {
      pFormStream.Reset(pFormPDFObj->AsMutableStream());
    }
  }

  RetainPtr<CPDF_Stream> pDataSetsStream;
  if (iDataSetsIndex != -1) {
    // Get datasets CPDF_Stream
    RetainPtr<CPDF_Object> pDataSetsPDFObj =
        pArray->GetMutableObjectAt(iDataSetsIndex);
    if (pDataSetsPDFObj->IsReference()) {
      CPDF_Reference* pDataSetsRefObj = pDataSetsPDFObj->AsMutableReference();
      RetainPtr<CPDF_Object> pDataSetsDirectObj =
          pDataSetsRefObj->GetMutableDirect();
      if (pDataSetsDirectObj && pDataSetsDirectObj->IsStream()) {
        pDataSetsStream.Reset(pDataSetsDirectObj->AsMutableStream());
      }
    } else if (pDataSetsPDFObj->IsStream()) {
      pDataSetsStream.Reset(pDataSetsPDFObj->AsMutableStream());
    }
  }
  // L"datasets"
  {
    RetainPtr<IFX_SeekableStream> pFileWrite =
        pdfium::MakeRetain<CFX_MemoryStream>();
    if (context->SaveDatasetsPackage(pFileWrite) && pFileWrite->GetSize() > 0) {
      if (iDataSetsIndex != -1) {
        if (pDataSetsStream) {
          pDataSetsStream->InitStreamFromFile(pFileWrite);
        }
      } else {
        auto data_stream = pPDFDocument->NewIndirect<CPDF_Stream>(
            pFileWrite, pPDFDocument->New<CPDF_Dictionary>());
        int iLast = fxcrt::CollectionSize<int>(*pArray) - 2;
        pArray->InsertNewAt<CPDF_String>(iLast, "datasets");
        pArray->InsertNewAt<CPDF_Reference>(iLast + 1, pPDFDocument,
                                            data_stream->GetObjNum());
      }
      fileList->push_back(std::move(pFileWrite));
    }
  }
  // L"form"
  {
    RetainPtr<IFX_SeekableStream> pFileWrite =
        pdfium::MakeRetain<CFX_MemoryStream>();
    if (context->SaveFormPackage(pFileWrite) && pFileWrite->GetSize() > 0) {
      if (iFormIndex != -1) {
        if (pFormStream) {
          pFormStream->InitStreamFromFile(pFileWrite);
        }
      } else {
        auto data_stream = pPDFDocument->NewIndirect<CPDF_Stream>(
            pFileWrite, pPDFDocument->New<CPDF_Dictionary>());
        int iLast = fxcrt::CollectionSize<int>(*pArray) - 2;
        pArray->InsertNewAt<CPDF_String>(iLast, "form");
        pArray->InsertNewAt<CPDF_Reference>(iLast + 1, pPDFDocument,
                                            data_stream->GetObjNum());
      }
      fileList->push_back(std::move(pFileWrite));
    }
  }
  return true;
}
#endif  // PDF_ENABLE_XFA

bool DoDocSave(FPDF_DOCUMENT document,
               FPDF_FILEWRITE* pFileWrite,
               FPDF_DWORD flags,
               std::optional<int> version) {
  CPDF_Document* pPDFDoc = CPDFDocumentFromFPDFDocument(document);
  if (!pPDFDoc) {
    return false;
  }

#ifdef PDF_ENABLE_XFA
  auto* context = static_cast<CPDFXFA_Context*>(pPDFDoc->GetExtension());
  if (context) {
    std::vector<RetainPtr<IFX_SeekableStream>> fileList;
    context->SendPreSaveToXFADoc(&fileList);
    SaveXFADocumentData(context, &fileList);
  }
#endif  // PDF_ENABLE_XFA

  if (flags < FPDF_INCREMENTAL || flags > FPDF_REMOVE_SECURITY) {
    flags = 0;
  }

  CPDF_Creator fileMaker(
      pPDFDoc, pdfium::MakeRetain<CPDFSDK_FileWriteAdapter>(pFileWrite));
  if (version.has_value()) {
    fileMaker.SetFileVersion(version.value());
  }
  if (flags == FPDF_REMOVE_SECURITY) {
    flags = 0;
    fileMaker.RemoveSecurity();
  }

  bool bRet = fileMaker.Create(static_cast<uint32_t>(flags));

#ifdef PDF_ENABLE_XFA
  if (context) {
    context->SendPostSaveToXFADoc();
  }
#endif  // PDF_ENABLE_XFA

  return bRet;
}

}  // namespace

FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV FPDF_SaveAsCopy(FPDF_DOCUMENT document,
                                                    FPDF_FILEWRITE* pFileWrite,
                                                    FPDF_DWORD flags) {
  return DoDocSave(document, pFileWrite, flags, {});
}

FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
FPDF_SaveWithVersion(FPDF_DOCUMENT document,
                     FPDF_FILEWRITE* pFileWrite,
                     FPDF_DWORD flags,
                     int fileVersion) {
  return DoDocSave(document, pFileWrite, flags, fileVersion);
}