/*
   orxonox - the future of 3D-vertical-scrollers

   Copyright (C) 2004 orx

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   ### File Specific:
   main-programmer: Christoph Renner
   co-programmer: ...
*/

//#define DEBUG_SPECIAL_MODULE DEBUG_MODULE_

#include "message_manager.h"

using namespace std;

MessageManager* MessageManager::singletonRef = NULL;


/**
 * standard constructor
*/
MessageManager::MessageManager ()
{
  this->setClassID( CL_MESSAGE_MANAGER, "MessageManager" );
  newNumber = 1;
  setSynchronized( true );
}


/**
 * standard deconstructor
*/
MessageManager::~MessageManager ()
{
  for ( MessageQueue::iterator it = messageQueue.begin(); it != messageQueue.end(); it++ )
  {
    for ( std::list<NetworkMessage>::iterator it2 = it->second.messages.begin(); it2 != it->second.messages.end(); it2++ )
    {
      if ( it2->data )
      {
        delete it2->data;
        it2->data = NULL;
      }
    }
    
    it->second.messages.clear();
    it->second.toAck.clear();
  }
  
  messageQueue.clear();
}

/**
 * get the diff to last acked state of userId
 *
 * this class does not use the normal SynchronizeableVars for zynchronisation. instead
 * it defines its own protocol
 *
 * @param userId user to create diff for
 * @param data buffer to copy diff in
 * @param maxLength max bytes to copy into data
 * @param stateId id of current state
 * @param fromStateId the reference state for the delta state
 * @param priorityTH tells getStateDiff to not send element with priority \< priorityTH
 * @return n bytes copied into data
 */
int MessageManager::getStateDiff( int userId, byte * data, int maxLength, int stateId, int fromStateId, int priorityTH )
{
  int i = 0;
  int n;
  
  n = Converter::intToByteArray( messageQueue[userId].toAck.size(), data + i, maxLength );
  i += n;
  assert( n == INTSIZE );
  
  for ( std::list<int>::iterator it = messageQueue[userId].toAck.begin(); it != messageQueue[userId].toAck.end(); it++)
  {
    n = Converter::intToByteArray( *it, data + i, maxLength );
    i += n;
    assert( n == INTSIZE );
  }
  
  messageQueue[userId].toAck.clear();
  
  n = Converter::intToByteArray( messageQueue[userId].messages.size(), data + i, maxLength );
  i += n;
  assert( n == INTSIZE );
  
  for ( std::list<NetworkMessage>::iterator it = messageQueue[userId].messages.begin(); it != messageQueue[userId].messages.end(); it++ )
  {
    n = Converter::intToByteArray( it->length, data + i, maxLength );
    i += n;
    assert( n == INTSIZE );
    
    n = Converter::intToByteArray( it->number, data + i, maxLength );
    i += n;
    assert( n == INTSIZE );
    
    n = Converter::intToByteArray( it->messageId, data + i, maxLength );
    i += n;
    assert( n == INTSIZE );
    
    assert( i + it->length <= maxLength );
    memcpy( data + i, it->data, it->length );
    i += it->length;
  }
  
  return i;
}

/**
 * sets a new state out of a diff created on another host
 * @param userId hostId of user who send me that diff
 * @param data pointer to diff
 * @param length length of diff
 * @param stateId id of current state
 * @param fromStateId id of the base state id
 * @return number bytes read
 * @todo check for permissions
 */
int MessageManager::setStateDiff( int userId, byte * data, int length, int stateId, int fromStateId )
{
  int i = 0;
  int n;
  
  int nAcks;
  
  assert( i + INTSIZE <= length );
  n = Converter::byteArrayToInt( data + i, &nAcks );
  assert( n == INTSIZE );
  i += n;
  
  std::list<int> acks;
  
  int number;
  
  for ( int j = 0; j < nAcks; j++ )
  {
    assert( i + INTSIZE <= length );
    n = Converter::byteArrayToInt( data + i, &number );
    assert( n == INTSIZE );
    i += n;
    
    acks.push_back( number );
  }
  
  int nMessages;
  
  assert( i + INTSIZE <= length );
  n = Converter::byteArrayToInt( data + i, &nMessages );
  assert( n == INTSIZE );
  i += n;

  int messageLength, messageId;
  
  for ( int j = 0; j < nMessages; j++ )
  {
    assert( i + INTSIZE <= length );
    n = Converter::byteArrayToInt( data + i, &messageLength );
    assert( n == INTSIZE );
    i += n;
    
    assert( i + INTSIZE <= length );
    n = Converter::byteArrayToInt( data + i, &number );
    assert( n == INTSIZE );
    i += n;
  
    assert( i + INTSIZE <= length );
    n = Converter::byteArrayToInt( data + i, &messageId );
    assert( n == INTSIZE );
    i += n;
    
    if ( number > 0 )
      messageQueue[userId].toAck.push_back( number );
    
    assert( i + messageLength <= length );
    assert( messageHandlerMap.find( (MessageId)messageId ) != messageHandlerMap.end() );
    if ( std::find( messageQueue[userId].recievedMessages.begin(), messageQueue[userId].recievedMessages.end(), number )== messageQueue[userId].recievedMessages.end() )
    {
      (*(messageHandlerMap[(MessageId)messageId].cb))( (MessageId)messageId, data + i, messageLength, messageHandlerMap[(MessageId)messageId].someData, userId );
      messageQueue[userId].recievedMessages.push_back( number );
    }
    i += messageLength;
  }
  
  
  //walk throu message queue and remove acked messages
  for ( std::list<NetworkMessage>::iterator it = messageQueue[userId].messages.begin(); it != messageQueue[userId].messages.end();  )
  {
    if ( std::find( acks.begin(), acks.end(), it->number) != acks.end() )
    {
      std::list<NetworkMessage>::iterator delIt = it;
      it++;
      messageQueue[userId].messages.erase( delIt );
      continue;
    }
    it++;
  }
  
  //TODO find bether way. maybe with timestamp
  if ( messageQueue[userId].recievedMessages.size() > 1000 )
  {
    for ( int j = 0; j < messageQueue[userId].recievedMessages.size() - 1000; j++ )
      messageQueue[userId].recievedMessages.erase( messageQueue[userId].recievedMessages.begin() );
  }

  return i;
}

/**
 * clean up memory reserved for user
 * @param userId userid
 */
void MessageManager::cleanUpUser( int userId )
{
  if ( messageQueue.find( userId ) == messageQueue.end() )
    return;
    
  for ( std::list<NetworkMessage>::iterator it = messageQueue[userId].messages.begin(); it != messageQueue[userId].messages.end(); it++ )
  {
    if ( it->data )
      delete it->data;
    it->data = NULL;
  }
  
  messageQueue[userId].toAck.clear();
  
  messageQueue.erase( userId );
}

/**
 * registers function to handle messages with id messageId. someData is passed to callbackfuntion
 * @param messageId message id to handle 
 * @param cb function pointer to callback function
 * @param someData this pointer is passed to callback function without modification
 * @return true on success
 */
bool MessageManager::registerMessageHandler( MessageId messageId, MessageCallback cb, void * someData )
{
  MessageHandler messageHandler;
  
  messageHandler.cb = cb;
  messageHandler.messageId = messageId;
  messageHandler.someData = someData;
  
  messageHandlerMap[messageId] = messageHandler;
  
  return true;
}

/**
 * initializes buffers for user
 * @param userId userId
 */
void MessageManager::initUser( int userId )
{
  // just do something so map creates a new entry
  messageQueue[userId].toAck.clear();
  assert( messageQueue[userId].messages.size() == 0 );
}

/**
 * send a message to one or more clients
 * recieverType:
 *               RT_ALL send to all users. reciever is ignored
 *               RT_USER send only to reciever
 *               RT_NOT_USER send to all but reciever
 *
 * @param messageId message id
 * @param data pointer to data
 * @param dataLength length of data
 * @param recieverType 
 * @param reciever 
 */
void MessageManager::sendMessage( MessageId messageId, byte * data, int dataLength, RecieverType recieverType, int reciever, MessagePriority messagePriority )
{
  for ( MessageQueue::iterator it = messageQueue.begin(); it != messageQueue.end(); it++ )
  {
    if ( 
         recieverType == RT_ALL ||
         recieverType == RT_USER && it->first == reciever ||
         recieverType == RT_NOT_USER && it->first != reciever
       )
    {
      NetworkMessage msg;
      
      msg.data = new byte[dataLength];
      memcpy( msg.data, data, dataLength );
      msg.length = dataLength;
      msg.messageId = messageId;
      msg.number = newNumber++;
      msg.priority = messagePriority;
      
      it->second.messages.push_back( msg );
    }
  }
}