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/** \file lispstring.h

 *  Defining a string class.

 */

#ifndef __lispstring_h__

#define __lispstring_h__

#include "yacasbase.h"

#include "grower.h"

#include "refcount.h"

class LispStringSmartPtr;

/** \class LispString : zero-terminated byte-counted string.

 * Also keeps a reference count for any one interested.

 * LispString is derived from CArrayGrower, so the function

 * Size returns the length of the buffer. Since the string

 * is also zero-terminated (for better interfacing with the normal

 * c functions), the string length is Size()-1.

 *

 * This class also allows the string to point to a buffer which is owned

 * by another part of the system, in which case it cannot be resized.

 * The array will then not be freed by this class.

 */

class LispString : public CArrayGrower >

{

public:

  // Constructors

    // The constructors allow the caller to specify whether the storage is owned externally.

  // Use the assignment operators to set the string after this.

    inline LispString(LispBoolean aStringOwnedExternally=LispFalse);

    inline LispString(LispString &aString, LispBoolean aStringOwnedExternally=LispFalse);

    inline LispString(LispChar * aString, LispBoolean aStringOwnedExternally);

    inline LispString(const LispChar * aString);

  // Assignment

  // This assignment abides by earlier functions setting the string as owned externally.

    inline LispString& operator=(LispChar * aString);

  // Assignments (with modifications).  This string cannot be owned externally.

    // Set string by taking part of another string.

    void SetStringCounted(const LispChar * aString, LispInt aLength);

    // Set string from other string, adding quotes around the string.

    void SetStringUnStringified(const LispChar * aString);

    // Set string from other string, removing quotes around the string.

    void SetStringStringified(const LispChar * aString);

  // Access

    inline LispChar * c_str() const;  // pointer to asciz 'C-string'

    // Comparison

  // If the string is in the hash table it is faster to compare the pointers to the strings

  // (instead of calling this routine), since in that case if they

    // are equal they should in fact be literally the same object.

    LispInt operator==(const LispString& aString);

    ~LispString();

private:

    inline void SetString(LispChar * aString, LispBoolean aStringOwnedExternally);

  void SetString(const LispChar * aString);

public:

  ReferenceCount iReferenceCount;

};

/** \class LispStringSmartPtr for managing strings outside

 of normal objects. This is the equivalent of LispPtr, maintaining

 a reference count for the string object.

 */

class LispStringSmartPtr

{

public:

  // Default constructor (not explicit, so it auto-initializes)

  LispStringSmartPtr() : iString(NULL) {}

  // Construct from pointer to LispString

  LispStringSmartPtr(LispString * aString) : iString(NULL)

  {

    this->operator=(aString);

  }

  // Copy constructor

  LispStringSmartPtr(const LispStringSmartPtr& aOther) : iString()

  {

    this->operator=(aOther.iString);

  }

  // Destructor

  ~LispStringSmartPtr();

  // Assignment from pointer.  (PDG - new method)

  // (we return void, not *this).

  LispStringSmartPtr& operator=(LispString * aString);

  // Assignment from another (the *default* simply assigns members, not what we want).

  // (we return void, not *this).

  LispStringSmartPtr& operator=(const LispStringSmartPtr &aOther) { this->operator=(aOther.iString); return *this; }

  // Expected pointer behavior.

  operator LispString*()    const { return  iString; }  // implicit conversion to pointer to T

  LispString *operator->()  const { return  iString; }  // so (smartPtr->member) accesses T's member

  // Operators below are not used yet, so they are commented out. If you want to use them you need to test if they work.

  //LispString &operator*() const { return *iString; }  // so (*smartPtr) is a reference to T

  //LispString *ptr()       const { return  iString; }  // so (smartPtr.ptr()) returns the pointer to T (boost calls this method 'get')

  //bool operator!()        const { return !iString; }  // is null pointer

private:

  LispString * iString;

};

#include "lispstring.inl"

#endif