//========================================================================

//

// OptionalContent.h

//

// Copyright 2008-2013 Glyph & Cog, LLC

//

//========================================================================

#ifndef OPTIONALCONTENT_H

#define OPTIONALCONTENT_H

#include <aconf.h>

#include "gtypes.h"

#include "Object.h"

#include "CharTypes.h"

class GString;

class GList;

class PDFDoc;

class TextString;

class XRef;

class OptionalContentGroup;

class OCDisplayNode;

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

class OptionalContent {

public:

  OptionalContent(PDFDoc *doc);

  ~OptionalContent();

  // Walk the list of optional content groups.

  int getNumOCGs();

  OptionalContentGroup *getOCG(int idx);

  // Find an OCG by indirect reference.

  OptionalContentGroup *findOCG(Ref *ref);

  // Get the root node of the optional content group display tree

  // (which does not necessarily include all of the OCGs).

  OCDisplayNode *getDisplayRoot() { return display; }

  // Evaluate an optional content object -- either an OCG or an OCMD.

  // If <obj> is a valid OCG or OCMD, sets *<visible> and returns

  // true; otherwise returns false.

  GBool evalOCObject(Object *obj, GBool *visible);

private:

  GBool evalOCVisibilityExpr(Object *expr, int recursion);

  XRef *xref;

  GList *ocgs;      // all OCGs [OptionalContentGroup]

  OCDisplayNode *display; // root node of display tree 

};

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

// Values from the optional content usage dictionary.

enum OCUsageState {

  ocUsageOn,

  ocUsageOff,

  ocUsageUnset

};

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

class OptionalContentGroup {

public:

  static OptionalContentGroup *parse(Ref *refA, Object *obj);

  ~OptionalContentGroup();

  GBool matches(Ref *refA);

  Unicode *getName();

  int getNameLength();

  OCUsageState getViewState() { return viewState; }

  OCUsageState getPrintState() { return printState; }

  GBool getState() { return state; }

  void setState(GBool stateA) { state = stateA; }

  GBool getInViewUsageAppDict() { return inViewUsageAppDict; }

  void setInViewUsageAppDict() { inViewUsageAppDict = gTrue; }

private:

  OptionalContentGroup(Ref *refA, TextString *nameA,

           OCUsageState viewStateA, OCUsageState printStateA);

  Ref ref;

  TextString *name;

  OCUsageState viewState, // suggested state when viewing

               printState;  // suggested state when printing

  GBool state;      // current state (on/off)

  GBool inViewUsageAppDict; // true if this OCG is listed in a

        //   usage app dict with Event=View

  friend class OCDisplayNode;

};

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

class OCDisplayNode {

public:

  static OCDisplayNode *parse(Object *obj, OptionalContent *oc, XRef *xref,

            int recursion = 0);

  OCDisplayNode();

  ~OCDisplayNode();

  Unicode *getName();

  int getNameLength();

  OptionalContentGroup *getOCG() { return ocg; }

  int getNumChildren();

  OCDisplayNode *getChild(int idx);

  OCDisplayNode *getParent() { return parent; }

private:

  OCDisplayNode(GString *nameA);

  OCDisplayNode(OptionalContentGroup *ocgA);

  void addChild(OCDisplayNode *child);

  void addChildren(GList *childrenA);

  GList *takeChildren();

  TextString *name;   // display name

  OptionalContentGroup *ocg;  // NULL for display labels

  OCDisplayNode *parent;  // parent node; NULL at root

  GList *children;    // NULL if there are no children

        //   [OCDisplayNode]

};

#endif