#include "TLSSession.h"
#include "TLSService.h"
#include "EPoll.h"
#include "Log.h"
#include "Exception.h"
//#include <openssl/rand.h>

namespace core {
   
   static int generate_session_id(const SSL *ssl, unsigned char *id, unsigned int *id_len) {
      char *session_id_prefix = (char *)"BARANT";
      unsigned int count = 0;
      Log(LOG_DEBUG_3) << "Generating unique session id.";
      do {
	 RAND_bytes(id, *id_len);
	 memcpy(id, session_id_prefix, (strlen(session_id_prefix) < *id_len));
      } while(SSL_has_matching_session_id(ssl, id, *id_len) && (++count < 10));
      return 1;
   }
   
   void handshake_complete(const SSL *ssl, int where, int ret) {
      Log(LOG_DEBUG_3) << "==>" << SSL_state_string_long(ssl) << "<==";
      if(where & SSL_CB_HANDSHAKE_DONE) {
	 X509 *ssl_client_cert = SSL_get_peer_certificate(ssl);
	 if(!ssl_client_cert) 
	   throw std::string("Unable to get peer certificate.");
	 X509_free(ssl_client_cert);
	 if(SSL_get_verify_result(ssl) != X509_V_OK)
	   throw std::string("Certificate verification failed.");
	 Log(LOG_DEBUG_3) << "Certificate verified successfully.";
      }
      else 
	Log(LOG_DEBUG_3) << "No client certificate.";
   }
   
   TLSSession::TLSSession(EPoll &ePoll, Service &service) : Session(ePoll, service) {}
   
   void TLSSession::init() {
      
      initialized = true;
      
      int ret;
      
      Log(LOG_DEBUG_3) << "TLS socket initializing...";
      
      fcntl(getDescriptor(), F_SETFL, fcntl(getDescriptor(), F_GETFL, 0) | O_NONBLOCK);
      
      if(!(ssl = SSL_new(((TLSService &)service).ctx))) 
	throw std::string("Error creating new TLS socket.");     
      
      SSL_set_info_callback(ssl, handshake_complete);
      
      if((ret = SSL_set_fd(ssl, getDescriptor())) == 0)
	throw std::string("Error setting TLS socket descriptor.");     
      
      if(!SSL_set_generate_session_id(ssl, generate_session_id))
	throw std::string("Error setting session identifier callback.");
      
      switch (SSL_get_error(ssl, SSL_accept(ssl))) {
       case SSL_ERROR_SSL:
         Log(LOG_DEBUG_3) << "ERROR_SSL on ssl_accept. errno=" << errno;
         break;
       case SSL_ERROR_WANT_READ:
         Log(LOG_DEBUG_3) << "ERROR_WANT_READ on ssl_accept.";
         break;
       case SSL_ERROR_WANT_WRITE:
         Log(LOG_DEBUG_3) << "ERROR_WANT_WRITE on ssl_accept.";
         break;
       case SSL_ERROR_SYSCALL:
         Log(LOG_DEBUG_3) << "ERROR_SYSCALL on ssl_accept. errno=" << errno;
         shutdown();
         break;
       default:
         Log(LOG_DEBUG_3) << "Unknown ERROR on ssl_accept.";
         break;
      }
   }
   
   TLSSession::~TLSSession() {
      
   }
   
   void TLSSession::protocol(std::string data) {
      
   }
   
   void TLSSession::receiveData(char *buffer, int bufferLength) {
      
      if(!initialized)
	init();
      
      int len;
      //   int error = -1;
      // 
      std::cout << "receiveData TLS" << std::endl;
      
      if((len = ::SSL_read(ssl, buffer, bufferLength)) >= 0) {
	 std::cout << "receiveData TLS...len=" << len << ":" << buffer << std::endl;
	 onDataReceived(std::string(buffer, len));             
      }
      else {
	 switch (SSL_get_error(ssl, len)) {
	  case SSL_ERROR_SSL:
	    Log(LOG_DEBUG_3) << "ERROR_SSL on ssl_read. error=" << errno;
	    break;
	  case SSL_ERROR_WANT_READ:
	    Log(LOG_DEBUG_3) << "ERROR_WANT_READ on ssl_read.";
	    break;
	  case SSL_ERROR_WANT_WRITE:
	    Log(LOG_DEBUG_3) << "ERROR_WANT_WRITE on ssl_read.";
	    break;
	  case SSL_ERROR_SYSCALL:
	    Log(LOG_DEBUG_3) << "ERROR_SYSCALL on ssl_read. errno=" << errno;
	    break;
	  default:
	    Log(LOG_DEBUG_3) << "Unknown ERROR on ssl_read.";
	    break;
	 }
      }

   }
   
   void TLSSession::output(std::stringstream &out) {
      out << "|" << ipAddress.getClientAddressAndPort();   
   }
   
}