/*----------------------------------------------------------------------------*/
/*                                                                            */
/* Copyright (c) 1995, 2004 IBM Corporation. All rights reserved.             */
/* Copyright (c) 2005-2014 Rexx Language Association. All rights reserved.    */
/*                                                                            */
/* This program and the accompanying materials are made available under       */
/* the terms of the Common Public License v1.0 which accompanies this         */
/* distribution. A copy is also available at the following address:           */
/* https://www.oorexx.org/license.html                                        */
/*                                                                            */
/* Redistribution and use in source and binary forms, with or                 */
/* without modification, are permitted provided that the following            */
/* conditions are met:                                                        */
/*                                                                            */
/* Redistributions of source code must retain the above copyright             */
/* notice, this list of conditions and the following disclaimer.              */
/* Redistributions in binary form must reproduce the above copyright          */
/* notice, this list of conditions and the following disclaimer in            */
/* the documentation and/or other materials provided with the distribution.   */
/*                                                                            */
/* Neither the name of Rexx Language Association nor the names                */
/* of its contributors may be used to endorse or promote products             */
/* derived from this software without specific prior written permission.      */
/*                                                                            */
/* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS        */
/* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT          */
/* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS          */
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/*                                                                            */
/*----------------------------------------------------------------------------*/
#ifndef ProtectedObject_Included
#define ProtectedObject_Included

class Activity;

class RexxInstruction;

/**
 * Base class for a protected object.
 */
class ProtectedBase
{
friend class Activity;
public:
    ProtectedBase();
    ProtectedBase(Activity *a);
    ~ProtectedBase();

    virtual void mark(size_t liveMark) = 0;
    virtual void markGeneral(int reason) = 0;

protected:

    ProtectedBase  *next;                // the pointer protected by the object
    Activity   *activity;            // the activity we're running on
};


/**
 * Normal untyped ProtectedObject class.  This protects
 * an object reference from garbage collection.
 */
class ProtectedObject : public ProtectedBase
{
 public:
     inline ProtectedObject() : protectedObject(OREF_NULL), ProtectedBase() { }
     inline ProtectedObject(Activity *a) : protectedObject(OREF_NULL), ProtectedBase(a) { }
     inline ProtectedObject(RexxInternalObject *o) : protectedObject(o), ProtectedBase() { }
     inline ProtectedObject(RexxInternalObject *o, Activity *a) : protectedObject(o), ProtectedBase(a) { }
     inline ~ProtectedObject() { }

     void mark(size_t liveMark)override { memory_mark(protectedObject); }
     void markGeneral(int reason)override { memory_mark_general(protectedObject); }

     inline ProtectedBase & operator=(RexxInternalObject *o)
     {
         protectedObject = o;
         return *this;
     }

     inline bool operator==(RexxInternalObject *o)
     {
         return protectedObject == o;
     }

     inline bool operator!=(RexxInternalObject *o)
     {
         return protectedObject != o;
     }

     // cast conversion operators for some very common uses of protected object.
     inline operator RexxObject *()
     {
         return (RexxObject *)protectedObject;
     }

     // cast conversion operators for some very common uses of protected object.
     inline operator RexxInternalObject *()
     {
         return protectedObject;
     }

     inline operator RexxObjectPtr()
     {
         return (RexxObjectPtr)protectedObject;
     }

     inline operator RexxString *()
     {
         return (RexxString *)protectedObject;
     }

     inline operator MethodClass *()
     {
         return (MethodClass *)protectedObject;
     }

     inline operator ArrayClass *()
     {
         return (ArrayClass *)protectedObject;
     }

     inline operator RexxClass *()
     {
         return (RexxClass *)protectedObject;
     }

     // this conversion helps the parsing process protect objects
     inline operator RexxInstruction *()
     {
         return (RexxInstruction *)protectedObject;
     }

     inline operator void *()
     {
         return (void *)protectedObject;
     }

     inline bool isNull()
     {
         return protectedObject == OREF_NULL;
     }

     // pointer access
     inline RexxObject * operator->()
     {
         return (RexxObject *)protectedObject;
     }

 protected:
     RexxInternalObject *protectedObject;   // The object we're protecting
};


/**
 * A single proctected object that can
 * protect multiple object instances.  Useful for
 * situations where there are a variable number of
 * things that require protecting.
 */
class ProtectedSet : public ProtectedObject
{
 public:
     inline ProtectedSet() : ProtectedObject() { }
     inline ProtectedSet(Activity *a) : ProtectedObject(a) { }
     inline ~ProtectedSet() { }

     void add(RexxInternalObject *);
};


/**
 * Typed version of a protected object.  Because this
 * uses templates, it is possible to use these like
 * normal pointers to invoke methods.  More useful where
 * operations need to be performed on a protected object
 * since it avoids lots of cast operations.
 */
template<class objType> class Protected : public ProtectedBase
{
 public:
     inline Protected() : protectedObject(OREF_NULL), ProtectedBase() { }
     inline Protected(Activity *a) : protectedObject(OREF_NULL), ProtectedBase(a) { }
     inline Protected(objType *o) : protectedObject(o), ProtectedBase() { }
     inline Protected(objType *o, Activity *a) : protectedObject(o), ProtectedBase(a) { }

     inline ~Protected() { }

     void mark(size_t liveMark)override { memory_mark(protectedObject); }
     void markGeneral(int reason)override { memory_mark_general(protectedObject); }

     inline ProtectedBase & operator=(objType *o)
     {
         protectedObject = o;
         return *this;
     }

     inline bool operator==(objType *o)
     {
         return protectedObject == o;
     }

     inline operator RexxObjectPtr()
     {
         return (RexxObjectPtr)protectedObject;
     }

     inline operator objType *()
     {
         return protectedObject;
     }

     inline operator void *()
     {
         return (void *)protectedObject;
     }

     inline bool isNull()
     {
         return protectedObject == OREF_NULL;
     }

     // pointer access
     inline objType *operator->()
     {
         return protectedObject;
     }

 protected:

    objType *protectedObject;          // the protected object.
};


#endif