/*************************************************
* ECDSA Header File                              *
* (C) 2007 Falko Strenzke, FlexSecure GmbH       *
* Defines classes ECDSA_Signature  and           *
* ECDSA_Signature_De/Encoder,                    *
*************************************************/

#ifndef BOTAN_ECDSA_H__
#define BOTAN_ECDSA_H__

#include <botan/bigint.h>
#include <botan/der_enc.h>
#include <botan/ber_dec.h>

namespace Botan {

class ECDSA_Signature_Decoder;
class ECDSA_Signature_Encoder;

class ECDSA_Signature
   {
      friend class ECDSA_Signature_Decoder;
      friend class ECDSA_Signature_Encoder;
   public:
      ECDSA_Signature(const BigInt& r, const BigInt& s);
      ECDSA_Signature()
         {}
      ;
      ECDSA_Signature(ECDSA_Signature const& other);
      ECDSA_Signature const& operator=(ECDSA_Signature const& other);

      BigInt const get_r() const
         {
         return m_r;
         }
      BigInt const get_s() const
         {
         return m_s;
         }
      /**
      * return the r||s
      */
      SecureVector<byte> const get_concatenation() const;


      ECDSA_Signature_Encoder* x509_encoder() const;
      ECDSA_Signature_Decoder* x509_decoder();
   private:
      BigInt m_r;
      BigInt m_s;
   };

bool operator== ( ECDSA_Signature const& lhs, ECDSA_Signature const& rhs );
inline bool operator!= ( ECDSA_Signature const& lhs, ECDSA_Signature const& rhs )
   {
   return !operator== ( lhs, rhs );
   }

class ECDSA_Signature_Decoder
   {
   public:
      void signature_bits(const MemoryRegion<byte>& bits)
         {
         BER_Decoder(bits)
            .start_cons(SEQUENCE)
            .decode(m_signature->m_r)
            .decode(m_signature->m_s)
            .verify_end()
            .end_cons();
         }
      ECDSA_Signature_Decoder(ECDSA_Signature* signature) : m_signature(signature)
         {}
   private:
      ECDSA_Signature* m_signature;
   };

class ECDSA_Signature_Encoder
   {
   public:
      MemoryVector<byte> signature_bits() const
         {
         return DER_Encoder()
            .start_cons(SEQUENCE)
            .encode(m_signature->m_r)
            .encode(m_signature->m_s)
            .end_cons()
            .get_contents();
         }
      ECDSA_Signature_Encoder(const ECDSA_Signature* signature) : m_signature(signature)
         {}
   private:
      const ECDSA_Signature* m_signature;
   };

ECDSA_Signature const decode_seq(MemoryRegion<byte> const& seq);
ECDSA_Signature const decode_concatenation(MemoryRegion<byte> const& concatenation);

}

#endif