/*
* ASN.1 OID
* (C) 1999-2007 Jack Lloyd
*
* Distributed under the terms of the Botan license
*/

#ifndef BOTAN_ASN1_OID_H__
#define BOTAN_ASN1_OID_H__

#include <botan/asn1_int.h>
#include <string>
#include <vector>

namespace Botan {

/**
* This class represents ASN.1 object identifiers.
*/
class BOTAN_DLL OID : public ASN1_Object
   {
   public:
      void encode_into(class DER_Encoder&) const;
      void decode_from(class BER_Decoder&);

      /**
      * Find out whether this OID is empty
      * @return true is no OID value is set
      */
      bool is_empty() const { return id.size() == 0; }

      /**
      * Get this OID as list (vector) of its components.
      * @return a vector representing this OID
      */
      std::vector<u32bit> get_id() const { return id; }

      /**
      * Get this OID as a string
      * @return a string representing this OID
      */
      std::string as_string() const;

      /**
      * Compare two OIDs.
      * @return true if they are equal, false otherwise
      */
      bool operator==(const OID&) const;

      /**
      * Reset this instance to an empty OID.
      */
      void clear();

      /**
      * Add a component to this OID.
      * @param new_comp the new component to add to the end of this OID
      * @return a reference to *this
      */
      OID& operator+=(u32bit new_comp);

      /**
      * Construct an OID from a string.
      * @param str a string in the form "a.b.c" etc., where a,b,c are numbers
      */
      OID(const std::string& str = std::string());
   private:
      std::vector<u32bit> id;
   };

/**
* Append another component onto the OID.
* @param oid the OID to add the new component to
* @param new_comp the new component to add
*/
OID operator+(const OID& oid, u32bit new_comp);

/**
* Compare two OIDs.
* @param a the first OID
* @param b the second OID
* @return true if a is not equal to b
*/
bool operator!=(const OID& a, const OID& b);

/**
* Compare two OIDs.
* @param a the first OID
* @param b the second OID
* @return true if a is lexicographically smaller than b
*/
bool operator<(const OID& a, const OID& b);

}

#endif
