/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set et sw=2 ts=2: */
/***************************************************************************
 *            munia_proto.cc
 *
 *  Fri Feb 24 08:23:16 CET 2012
 *  Copyright 2012 Bent Bisballe Nyeng
 *  deva@aasimon.org
 ****************************************************************************/

/*
 *  This file is part of Munia.
 *
 *  Munia 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 of the License, or
 *  (at your option) any later version.
 *
 *  Munia is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with Munia; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
 */
#include "munia_proto.h"

#include <stdio.h>
#include <string.h>

#include <queue>
#include <map>

#include "debug.h"

#include "task.h"
#include "messageparser.h"
#include "messagehandler.h"
#include "connectionhandler.h"

// Defines global task_manager object
#include "taskmanager.h"

#if 0
static void dump_handshake_info(struct lws_tokens *lwst)
{
  int n;
  static const char *token_names[WSI_TOKEN_COUNT] = {
    /*[WSI_TOKEN_GET_URI]     =*/ "GET URI",
    /*[WSI_TOKEN_HOST]        =*/ "Host",
    /*[WSI_TOKEN_CONNECTION]  =*/ "Connection",
    /*[WSI_TOKEN_KEY1]        =*/ "key 1",
    /*[WSI_TOKEN_KEY2]        =*/ "key 2",
    /*[WSI_TOKEN_PROTOCOL]    =*/ "Protocol",
    /*[WSI_TOKEN_UPGRADE]     =*/ "Upgrade",
    /*[WSI_TOKEN_ORIGIN]      =*/ "Origin",
    /*[WSI_TOKEN_DRAFT]       =*/ "Draft",
    /*[WSI_TOKEN_CHALLENGE]   =*/ "Challenge",

    /* new for 04 */
    /*[WSI_TOKEN_KEY]         =*/ "Key",
    /*[WSI_TOKEN_VERSION]     =*/ "Version",
    /*[WSI_TOKEN_SWORIGIN]    =*/ "Sworigin",

    /* new for 05 */
    /*[WSI_TOKEN_EXTENSIONS]  =*/ "Extensions",

    /* client receives these */
    /*[WSI_TOKEN_ACCEPT]      =*/ "Accept",
    /*[WSI_TOKEN_NONCE]       =*/ "Nonce",
    /*[WSI_TOKEN_HTTP]        =*/ "Http",
    /*[WSI_TOKEN_MUXURL]      =*/ "MuxURL",
  };

  for (n = 0; n < WSI_TOKEN_COUNT; n++) {
    if (lwst[n].token == NULL || lwst[n].token_len == 0) continue;
    fprintf(stderr, "    %s = ", token_names[n]);
    if(fwrite(lwst[n].token, 1, lwst[n].token_len, stderr)) {}
    fprintf(stderr, "\n");
  }
}
#endif

typedef std::list<message_t> msgqueue_t;
static std::map<struct libwebsocket *, msgqueue_t > msgqueue;
struct libwebsocket *current_client = NULL;

int callback_lws_task(struct libwebsocket_context * context,
                      struct libwebsocket *wsi,
                      enum libwebsocket_callback_reasons reason,
                      void *user, void *in, size_t len)
{
  task_manager.tree.toStdOut();

  printf("Callback on %p\n", wsi);

  switch (reason) {
  case LWS_CALLBACK_ESTABLISHED:
    connection_handler.init(wsi);
    break;

  case LWS_CALLBACK_CLOSED:
    connection_handler.close(wsi);
    break;

  case LWS_CALLBACK_SERVER_WRITEABLE:
    {
      //
      // Find and collapse remove/create msg's into single move msg at
      // the position of the remove msg.
      //
      msgqueue_t::iterator i = msgqueue[wsi].begin();
      while(i != msgqueue[wsi].end()) {
        message_t &msg = *i;
        if(msg.cmd == cmd::remove) {

          msgqueue_t::iterator j = msgqueue[wsi].begin();
          while(j != msgqueue[wsi].end()) {
            message_t m = *j;
            if(m.cmd == cmd::create && // msg was a create msg?
               // created with same ids as we just removed?
               msg.remove.id == m.create.id && 
               msg.tid == m.tid) {
              break;
            }
            j++;
          }
          
          // collapse into move msg
          if(j != msgqueue[wsi].end()) {
            taskid_t id = j->create.id;
            taskid_t parentid = j->create.parentid;
            msgqueue[wsi].erase(j); // erase create msg
            msg.cmd = cmd::move;
            msg.move.id = id;
            msg.move.parentid = parentid;
          }
        }
        i++;
      }

      std::string msgstr;
      msgstr.append((size_t)LWS_SEND_BUFFER_PRE_PADDING, ' ');

      if(msgqueue[wsi].size() == 0 && wsi == current_client) msgstr += ";";

      while(msgqueue[wsi].size() > 0) {
        message_t msg = msgqueue[wsi].front();
        msgqueue[wsi].pop_front();
        char buf[32];
        sprintf(buf, "%d", msg.tid);
        if(msgstr.size() > LWS_SEND_BUFFER_PRE_PADDING) msgstr += " ";
        msgstr += std::string(buf) + " " + msg_tostring(msg);
      }
     
     
      msgstr.append((size_t)LWS_SEND_BUFFER_POST_PADDING, ' ');

      int n = libwebsocket_write(wsi, (unsigned char *)
                                 msgstr.c_str() +
                                 LWS_SEND_BUFFER_PRE_PADDING,
                                 msgstr.length() -
                                 LWS_SEND_BUFFER_POST_PADDING -
                                 LWS_SEND_BUFFER_PRE_PADDING,
                                 LWS_WRITE_TEXT);
      if(n < 0) {
        fprintf(stderr, "ERROR writing to socket");
        exit(1);
      }
    }

    break;

    /*
  case LWS_CALLBACK_BROADCAST:
    printf("LWS_CALLBACK_BROADCAST\n");
    n = libwebsocket_write(wsi, (unsigned char*)in, len, LWS_WRITE_TEXT);
    if (n < 0) fprintf(stderr, "task write failed\n");
    break;
    */

  case LWS_CALLBACK_RECEIVE:
    {
      DEBUG(proto, "LWS_CALLBACK_RECEIVE\n");

      current_client = wsi;

      printf("%s\n", (char*)in);
      std::string data;
      data.append((char*)in, len);

      MessageList mlst = parse_msg(data);
      DEBUG(proto, "Handling %d incoming message\n", mlst.size());
      MessageList omsgs = handle_msg(mlst, wsi);
      DEBUG(proto, "Handling %d outgoing messages\n", omsgs.size());

      MessageList::iterator omi = omsgs.begin();
      while(omi != omsgs.end()) {
        DEBUG(proto, "Message\n");
        if(omi->cmd == cmd::observe) {
          connection_handler.observe(wsi, omi->observe.id);
          TaskIdList ids;
          try {
            ids = task_manager.subTasks(omi->observe.id);
          } catch(...) {
            DEBUG(proto, "No such node %d\n", omi->observe.id);
            omi++;
            continue;
          }
          TaskIdList::iterator id = ids.begin();
          while(id != ids.end()) {
            task_t task = task_manager.task(*id);

            message_t createmsg = create_msg_create(task);
            createmsg.tid = omi->observe.id;
            message_t updatemsg = create_msg_update(task);
            updatemsg.tid = omi->observe.id;

            msgqueue[wsi].push_back(createmsg);
            msgqueue[wsi].push_back(updatemsg);
          
            id++;
          }
          
        } else if(omi->cmd == cmd::unobserve) {
          connection_handler.unobserve(wsi, omi->observe.id);
          TaskIdList ids;
          try {
            ids = task_manager.subTasks(omi->observe.id);
          } catch(...) {
            DEBUG(proto, "No such node %d\n", omi->observe.id);
            omi++;
            continue;
          }
          TaskIdList::reverse_iterator id = ids.rbegin();
          while(id != ids.rend()) {
            task_t task = task_manager.task(*id);
          
            message_t removemsg = create_msg_remove(task);
            removemsg.tid = omi->observe.id;
            msgqueue[wsi].push_back(removemsg);
            
            id++;
          }

        } else {
          DEBUG(proto, "%d nodes affected by command\n", omi->nodes.size());

          ObserverList clients = connection_handler.observerlist(omi->nodes);
          DEBUG(proto, "Writing message to %d clients\n", clients.size());

          ObserverList::iterator ci = clients.begin();
          while(ci != clients.end()) {
            clientid_t clientid = (*ci).first;
            taskid_t tid = (*ci).second;

            DEBUG(proto, "Observer id of task: %d\n", tid);

            message_t msg = *omi;
            msg.tid = tid;

            msgqueue[clientid].push_back(msg);

            ci++;
          }
        }
        
        omi++;
      }

      libwebsocket_callback_on_writable_all_protocol(
                                libwebsockets_get_protocol(wsi));
    }
    break;

  default:
    break;
  }

  return 0;
}