QPDFOutlineDocumentHelper.hh 3.17 KB
// Copyright (c) 2005-2021 Jay Berkenbilt
// Copyright (c) 2022-2026 Jay Berkenbilt and Manfred Holger
//
// This file is part of qpdf.
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
// in compliance with the License. You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software distributed under the License
// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
// or implied. See the License for the specific language governing permissions and limitations under
// the License.
//
// Versions of qpdf prior to version 7 were released under the terms of version 2.0 of the Artistic
// License. At your option, you may continue to consider qpdf to be licensed under those terms.
// Please see the manual for additional information.

#ifndef QPDFOUTLINEDOCUMENTHELPER_HH
#define QPDFOUTLINEDOCUMENTHELPER_HH

#include <qpdf/QPDF.hh>
#include <qpdf/QPDFDocumentHelper.hh>
#include <qpdf/QPDFNameTreeObjectHelper.hh>
#include <qpdf/QPDFObjGen.hh>
#include <qpdf/QPDFOutlineObjectHelper.hh>

#include <map>
#include <vector>

#include <qpdf/DLL.h>

// This is a document helper for outlines, also known as bookmarks. Outlines are discussed in
// section 12.3.3 of the PDF spec (ISO-32000). With the help of QPDFOutlineObjectHelper, the
// outlines tree is traversed, and a bidirectional map is made between pages and outlines. See also
// QPDFOutlineObjectHelper.
class QPDFOutlineDocumentHelper: public QPDFDocumentHelper
{
  public:
    // Get a shared document helper for a given QPDF object.
    //
    // Retrieving a document helper for a QPDF object rather than creating a new one avoids repeated
    // validation of the Acroform structure, which can be expensive.
    QPDF_DLL
    static QPDFOutlineDocumentHelper& get(QPDF& qpdf);

    // Re-validate the Outlines structure. This is useful if you have modified the structure of the
    // Outlines dictionary in a way that would invalidate the cache.
    //
    // If repair is true, the document will be repaired if possible if the validation encounters
    // errors.
    QPDF_DLL
    void validate(bool repair = true);

    QPDF_DLL
    QPDFOutlineDocumentHelper(QPDF&);

    ~QPDFOutlineDocumentHelper() override = default;

    QPDF_DLL
    bool hasOutlines();

    QPDF_DLL
    std::vector<QPDFOutlineObjectHelper> getTopLevelOutlines();

    // If the name is a name object, look it up in the /Dests key of the document catalog. If the
    // name is a string, look it up in the name tree pointed to by the /Dests key of the names
    // dictionary.
    QPDF_DLL
    QPDFObjectHandle resolveNamedDest(QPDFObjectHandle name);

    // Return a list outlines that are known to target the specified page.
    QPDF_DLL
    std::vector<QPDFOutlineObjectHelper> getOutlinesForPage(QPDFObjGen);

    class Accessor
    {
        friend class QPDFOutlineObjectHelper;

        static bool checkSeen(QPDFOutlineDocumentHelper& dh, QPDFObjGen og);
    };

  private:
    void initializeByPage();

    class Members;

    std::shared_ptr<Members> m;
};

#endif // QPDFOUTLINEDOCUMENTHELPER_HH