poppler/OptionalContent.h

//========================================================================
//
// OptionalContent.h
//
// Copyright 2007 Brad Hards <bradh@kde.org>
// Copyright 2008 Carlos Garcia Campos <carlosgc@gnome.org>
// Copyright 2013, 2018, 2019 Albert Astals Cid <aacid@kde.org>
// Copyright 2018 Adam Reichold <adam.reichold@t-online.de>
// Copyright 2019 Oliver Sander <oliver.sander@tu-dresden.de>
//
// Released under the GPL (version 2, or later, at your option)
//
//========================================================================

#ifndef OPTIONALCONTENT_H
#define OPTIONALCONTENT_H

#include "Object.h"
#include "CharTypes.h"
#include <unordered_map>
#include <memory>

class GooString;
class XRef;

class OptionalContentGroup;
class OCDisplayNode;

//------------------------------------------------------------------------

class OCGs {
public:

  OCGs(Object *ocgObject, XRef *xref);

  OCGs(const OCGs &) = delete;
  OCGs& operator=(const OCGs &) = delete;

  // Is OCGS valid?
  bool isOk() const { return ok; }
  
  bool hasOCGs() const;
  const std::unordered_map< Ref, std::unique_ptr< OptionalContentGroup > > &getOCGs() const { return optionalContentGroups; }

  OptionalContentGroup* findOcgByRef( const Ref ref);

  // Get the root node of the optional content group display tree
  // (which does not necessarily include all of the OCGs).
  OCDisplayNode *getDisplayRoot();

  Array* getOrderArray() 
    { return (order.isArray() && order.arrayGetLength() > 0) ? order.getArray() : nullptr; }
  Array* getRBGroupsArray() 
    { return (rbgroups.isArray() && rbgroups.arrayGetLength()) ? rbgroups.getArray() : nullptr; }

  bool optContentIsVisible( const Object *dictRef );

private:
  bool ok;

  bool evalOCVisibilityExpr(const Object *expr, int recursion);
  bool allOn( Array *ocgArray );
  bool allOff( Array *ocgArray );
  bool anyOn( Array *ocgArray );
  bool anyOff( Array *ocgArray );

  std::unordered_map< Ref, std::unique_ptr< OptionalContentGroup > > optionalContentGroups;

  Object order;
  Object rbgroups;
  XRef *m_xref;
  std::unique_ptr< OCDisplayNode > display; // root node of display tree
};

//------------------------------------------------------------------------

class OptionalContentGroup {
public:
  enum State { On, Off };

  // Values from the optional content usage dictionary.
  enum UsageState {
    ocUsageOn,
    ocUsageOff,
    ocUsageUnset
  };

  OptionalContentGroup(Dict *dict);

  OptionalContentGroup(GooString *label);

  ~OptionalContentGroup();

  OptionalContentGroup(const OptionalContentGroup &) = delete;
  OptionalContentGroup& operator=(const OptionalContentGroup &) = delete;

  const GooString* getName() const;

  Ref getRef() const;
  void setRef(const Ref ref);

  State getState() const { return m_state; };
  void setState(State state) { m_state = state; };

  UsageState getViewState() const { return viewState; }
  UsageState getPrintState() const { return printState; }

private:
  GooString *m_name;
  Ref m_ref;
  State m_state;
  UsageState viewState;	 // suggested state when viewing
  UsageState printState; // suggested state when printing
};

//------------------------------------------------------------------------

class OCDisplayNode {
public:

  static OCDisplayNode *parse(const Object *obj, OCGs *oc, XRef *xref, int recursion = 0);
  OCDisplayNode();
  ~OCDisplayNode();

  OCDisplayNode(const OCDisplayNode &) = delete;
  OCDisplayNode& operator=(const OCDisplayNode &) = delete;

  const GooString *getName() const { return name; }
  const OptionalContentGroup *getOCG() const { return ocg; }
  int getNumChildren() const;
  OCDisplayNode *getChild(int idx) const;

private:

  OCDisplayNode(const GooString *nameA);
  OCDisplayNode(OptionalContentGroup *ocgA);
  void addChild(OCDisplayNode *child);
  void addChildren(std::vector<OCDisplayNode*> *childrenA);
  std::vector<OCDisplayNode*> *takeChildren();

  GooString *name;		// display name (may be nullptr)
  OptionalContentGroup *ocg;	// nullptr for display labels
  std::vector<OCDisplayNode*> *children;		// nullptr if there are no children
				//   [OCDisplayNode]
};

#endif