/*

 * ibb.c

 *

 * Copyrigth (C) 2010 Nicolas Cornu <nicolas.cornu@ensi-bourges.fr>

 *

 * 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 of the License, or (at

 * your option) any later version.

 *

 * This program 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 this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307

 * USA

 */

#include "config.h"

#include <glib.h>

#include <string.h>

#include <mcabber/xmpp.h>

#include <mcabber/modules.h>

#include <mcabber/utils.h>

#include <mcabber/xmpp_helper.h>

#include <mcabber/logprint.h>

#include <mcabber/hooks.h>

#include <jingle/jingle.h>

#include <jingle/check.h>

#include <jingle/register.h>

#include <jingle/sessions.h>

#include "ibb.h"

static LmMessageHandler* jingle_ibb_handler = NULL;

static gconstpointer check(JingleContent *cn, GError **err);

static gboolean cmp(gconstpointer data1, gconstpointer data2);

static void tomessage(gconstpointer data, LmMessageNode *node);

static gconstpointer new(void);

static void send(session_content *sc, gconstpointer data, gchar *buf, gsize size);

static void init(session_content *sc, gconstpointer data);

static void end(session_content *sc, gconstpointer data);

static void _send_internal(session_content *sc, const gchar *to, gchar *buf,

                           gsize size, const gchar *sid, gint64 *seq);

static void jingle_ibb_init(void);

static void jingle_ibb_uninit(void);

static guint connect_hid = 0;

static guint disconn_hid = 0;

const gchar *deps[] = { "jingle", NULL };

static JingleTransportFuncs funcs = {

  .check     = check,

  .tomessage = tomessage,

  .cmp       = cmp,

  .new       = new,

  .send      = send,

  .init      = init,

};

module_info_t  info_jingle_inbandbytestream = {

  .branch          = MCABBER_BRANCH,

  .api             = MCABBER_API_VERSION,

  .version         = PROJECT_VERSION,

  .description     = "Jingle In Band Bytestream (XEP-0261)\n",

  .requires        = deps,

  .init            = jingle_ibb_init,

  .uninit          = jingle_ibb_uninit,

  .next            = NULL,

};

static gconstpointer check(JingleContent *cn, GError **err)

{

  JingleIBB *ibb = NULL;

  LmMessageNode *node = cn->transport;

  const gchar *blocksize;

  ibb = g_new0(JingleIBB, 1);

  blocksize  = lm_message_node_get_attribute(node, "block-size");

  ibb->sid = g_strdup(lm_message_node_get_attribute(node, "sid"));

  if (!ibb->sid || !blocksize) {

    g_set_error(err, JINGLE_CHECK_ERROR, JINGLE_CHECK_ERROR_MISSING,

                "an attribute of the transport element is missing");

    g_free(ibb);

    return NULL;

  }

  ibb->blocksize = g_ascii_strtoll(blocksize, NULL, 10);

  // If block size is too big, we change it

  if (ibb->blocksize > IBB_BLOCK_SIZE_MAX) {

    ibb->blocksize = IBB_BLOCK_SIZE_MAX;

    return NULL;

  }

  ibb->blocksize = 2048;

  // the blocksize attribute is a xs:short an therefore can be negative.

  if (ibb->blocksize < 0) {

    g_set_error(err, JINGLE_CHECK_ERROR, JINGLE_CHECK_ERROR_BADVALUE,

                "block-size is negative");

    g_free(ibb->sid);

    g_free(ibb);

    return NULL;

  }

  return (gconstpointer) ibb;

}

LmHandlerResult jingle_ibb_handle_iq(LmMessageHandler *handler,

                                 LmConnection *connection, LmMessage *message,

                                 gpointer user_data)

{

  const gchar *data64;

  JingleIBB *jibb = g_new0(JingleIBB, 1);

  gsize len;

  guchar *data;

  LmMessageSubType iqtype = lm_message_get_sub_type(message);

  if (iqtype != LM_MESSAGE_SUB_TYPE_SET)

    return LM_HANDLER_RESULT_ALLOW_MORE_HANDLERS;

  LmMessageNode *root = lm_message_get_node(message);

  LmMessageNode *dnode = lm_message_node_get_child(root, "data");

  if (!dnode) // no <data> element found

    return LM_HANDLER_RESULT_ALLOW_MORE_HANDLERS;

  if (g_strcmp0(lm_message_node_get_attribute(dnode, "xmlns"),

                NS_TRANSPORT_IBB))

    return LM_HANDLER_RESULT_REMOVE_MESSAGE;

  jingle_ack_iq(message);

  jibb->sid = g_strdup(lm_message_node_get_attribute(dnode, "sid"));

  jibb->seq = g_ascii_strtoll(lm_message_node_get_attribute(dnode, "seq"), NULL, 10);

  data64 = lm_message_node_get_value(dnode);

  data = g_base64_decode(data64, &len);

  handle_trans_data(NS_JINGLE_TRANSPORT_IBB, jibb, (const gchar *)data, (guint)len);

  return LM_HANDLER_RESULT_REMOVE_MESSAGE;

}

static gboolean cmp(gconstpointer data1, gconstpointer data2)

{

  const JingleIBB *ibb1 = data1, *ibb2 = data2;

  if(g_strcmp0(ibb1->sid, ibb2->sid))

    return FALSE;

  return TRUE;

}

static gchar *new_ibb_sid(void)

{

  gchar *sid;

  gchar car[] = "azertyuiopqsdfghjklmwxcvbn1234567890AZERTYUIOPQSDFGHJKLMWXCVBN";

  int i;

  sid = g_new0(gchar, 7);

  for (i = 0; i < 6; i++)

    sid[i] = car[g_random_int_range(0, sizeof(car)/sizeof(car[0]))];

  sid[6] = '\0';

  return sid;

}

static gconstpointer new(void)

{

  JingleIBB *ibb = g_new0(JingleIBB, 1);

  ibb->blocksize = IBB_BLOCK_SIZE_MAX;

  ibb->sid = new_ibb_sid();

  ibb->seq = 0;

  return ibb;

}

int jingle_ibb_check_session(gconstpointer data, gconstpointer session)

{

  const JingleIBB *ibb1 = data, *ibb2 = session;

  if(!g_strcmp0(ibb1->sid, ibb2->sid) && ibb1->seq == ibb2->seq + 1)

    return 0;

  return 1;

}

static void tomessage(gconstpointer data, LmMessageNode *node)

{

  JingleIBB *jibb = (JingleIBB*) data;

  gchar *bsize = g_strdup_printf("%i", jibb->blocksize);

  if (lm_message_node_get_child(node, "transport") != NULL)

    return;

  LmMessageNode *node2 = lm_message_node_add_child(node, "transport", NULL);

  lm_message_node_set_attributes(node2, "xmlns", NS_JINGLE_TRANSPORT_IBB,

                                 "sid", jibb->sid,

                                 "block-size", bsize,

                                 NULL);

  g_free(bsize);

}

static void jingle_ibb_handle_ack_iq_send(LmMessage *mess, gpointer data)

{

  // TODO: check the sub type (error ??)

  session_content *sc = (session_content *)data;

  JingleSession *sess = session_find_by_sid(sc->sid, sc->from);

  // If there is no more session, maybe it's finish

  if (sess == NULL)

    return;

  SessionContent *sc2 = session_find_sessioncontent(sess, sc->name);

  JingleIBB *jibb = (JingleIBB *)sc2->transport;

  // We look if there is enough data staying

  if (jibb->dataleft > jibb->blocksize) {

    gchar *buf = g_memdup(jibb->buf, jibb->blocksize);

    jibb->dataleft-=jibb->blocksize;

    g_memmove(jibb->buf, jibb->buf+jibb->blocksize, jibb->dataleft);

    _send_internal(sc, sess->to, buf, jibb->blocksize, jibb->sid, &jibb->seq);

    g_free(buf);

  } else { // ask for more data

    handle_trans_next(sc);

  }

}

static void _send_internal(session_content *sc, const gchar *to, gchar *buf,

                           gsize size, const gchar *sid, gint64 *seq)

{

  JingleAckHandle *ackhandle;

  LmMessage *r = lm_message_new_with_sub_type(to, LM_MESSAGE_TYPE_IQ,

                                              LM_MESSAGE_SUB_TYPE_SET);

  LmMessageNode *node = lm_message_get_node(r);

  gchar *base64 = g_base64_encode((const guchar *)buf, size);

  gchar *strseq = g_strdup_printf("%" G_GINT64_FORMAT, *seq);

  node = lm_message_node_add_child(node, "data", NULL);

  lm_message_node_set_attributes(node, "xmlns", NS_TRANSPORT_IBB,

                                 "sid", sid,

                                 "seq", strseq,

                                 NULL);

  lm_message_node_set_value(node, base64);

  ackhandle = g_new0(JingleAckHandle, 1);

  ackhandle->callback = jingle_ibb_handle_ack_iq_send;

  ackhandle->user_data = (gpointer)sc;

  lm_connection_send_with_reply(lconnection, r,

                                jingle_new_ack_handler(ackhandle), NULL);

  lm_message_unref(r);

  // The next packet will be seq++

  ++(*seq);

  g_free(base64);

  g_free(strseq);

}

static void send(session_content *sc, gconstpointer data, gchar *buf,

                     gsize size)

{

  JingleIBB *jibb = (JingleIBB*)data;

  if (jibb->size_buf >= size + jibb->dataleft) {

    g_memmove(jibb->buf + jibb->dataleft, buf, size);

    jibb->dataleft+=size;

  } else {

    jibb->size_buf = size + jibb->dataleft;

    jibb->buf = g_realloc(jibb->buf, jibb->size_buf);

    g_memmove(jibb->buf + jibb->dataleft, buf, size);

    jibb->dataleft = jibb->size_buf;

  }

  // We need more data

  if (jibb->dataleft < jibb->blocksize) {

    handle_trans_next(sc);

    return;

  }

  // It's enough

  {

    JingleSession *sess = session_find_by_sid(sc->sid, sc->from);

    gchar *buffer = g_memdup(jibb->buf, jibb->blocksize);

    jibb->dataleft-=jibb->blocksize;

    g_memmove(jibb->buf, jibb->buf+jibb->blocksize, jibb->dataleft);

    _send_internal(sc, sess->to, buffer, jibb->blocksize, jibb->sid,

                   &jibb->seq);

    g_free(buffer);

  }

}

static void init(session_content *sc, gconstpointer data)

{

  JingleIBB *jibb = (JingleIBB*)data;

  JingleSession *sess = session_find_by_sid(sc->sid, sc->from);

  SessionContent *sc2 = session_find_sessioncontent(sess, sc->name);

  JingleIBB *jibb2 = (JingleIBB*)sc2->transport;

  jibb2->blocksize = (jibb->blocksize < jibb2->blocksize)?jibb->blocksize:jibb2->blocksize;

}

static void end(session_content *sc, gconstpointer data)

{

  JingleIBB *jibb = (JingleIBB*)data;

  JingleSession *sess = session_find_by_sid(sc->sid, sc->from);

  if (jibb->dataleft > 0) {

    _send_internal(sc, sess->to, jibb->buf, jibb->dataleft, jibb->sid,

                   &jibb->seq);

  }

  g_free(jibb->buf);

}

static void jingle_ibb_unregister_lm_handlers(void)

{

  if (lconnection) {

    lm_connection_unregister_message_handler(lconnection, jingle_ibb_handler,

        LM_MESSAGE_TYPE_IQ);

  }

}

static void jingle_ibb_register_lm_handlers(void)

{

  jingle_ibb_unregister_lm_handlers();

  if (lconnection) {

    lm_connection_register_message_handler(lconnection, jingle_ibb_handler,

        LM_MESSAGE_TYPE_IQ,

        LM_HANDLER_PRIORITY_FIRST);

  }

}

static guint jingle_ibb_connect_hh(const gchar *hname, hk_arg_t *args,

                               gpointer ignore)

{

  jingle_ibb_register_lm_handlers();

  return HOOK_HANDLER_RESULT_ALLOW_MORE_HANDLERS;

}

static guint jingle_ibb_disconn_hh(const gchar *hname, hk_arg_t *args,

                               gpointer ignore)

{

  jingle_ibb_unregister_lm_handlers();

  return HOOK_HANDLER_RESULT_ALLOW_MORE_HANDLERS;

}

static void jingle_ibb_init(void)

{

  jingle_ibb_handler = lm_message_handler_new(jingle_ibb_handle_iq, NULL, NULL);

  connect_hid = hk_add_handler(jingle_ibb_connect_hh, HOOK_POST_CONNECT,