/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */

/*

 * Copyright (C) 2003 Imendio HB

 * Copyright (C) 2003 Mikael Hallendal <micke@imendio.com>

 * Copyright (C) 2003 CodeFactory AB. 

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser 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>

#ifdef HAVE_GNUTLS

#include <gnutls/gnutls.h>

#endif

#include <string.h>

#include <unistd.h>

#include <sys/types.h>

#ifndef __WIN32__

  #include <netdb.h>

  #include <sys/socket.h>

  #include <netinet/in.h>

#else

  #include <winsock2.h>

#endif

#include "lm-debug.h"

#include "lm-error.h"

#include "lm-internals.h"

#include "lm-parser.h"

#include "lm-sha.h"

#include "lm-connection.h"

#define IN_BUFFER_SIZE 1024

typedef struct {

	LmHandlerPriority  priority;

	LmMessageHandler  *handler;

} HandlerData;

typedef struct {

	GSource source;

	LmConnection *connection;

} LmIncomingSource;

struct _LmConnection {

	/* Parameters */

	gchar          *server;

	guint           port;

	gboolean        use_ssl;

#ifdef HAVE_GNUTLS

	gnutls_session  gnutls_session;

	gnutls_certificate_client_credentials gnutls_xcred;

#endif

	gboolean    is_open;

	gboolean    is_authenticated;

	LmParser   *parser;

	gchar      *stream_id;

	GHashTable *id_handlers;

	GSList     *handlers[LM_MESSAGE_TYPE_UNKNOWN];

	/* Communication */

	GIOChannel *io_channel;

	guint       io_watch_in;

	guint       io_watch_err;

	guint       io_watch_hup;

	LmCallback *open_cb;

	LmCallback *close_cb;

	LmCallback *auth_cb;

	LmCallback *register_cb;

	LmCallback *disconnect_cb;

	GQueue     *incoming_messages;

	GSource    *incoming_source;

	gint        ref_count;

};

typedef enum {

	AUTH_TYPE_PLAIN  = 1,

	AUTH_TYPE_DIGEST = 2,

	AUTH_TYPE_0K     = 4

} AuthType;

static void     connection_free (LmConnection *connection);

static void     connection_handle_message    (LmConnection         *connection,

					      LmMessage            *message);

static void     connection_new_message_cb    (LmParser             *parser,

					      LmMessage            *message,

					      LmConnection         *connection);

static gboolean connection_do_open         (LmConnection     *connection,

					      GError          **error);

static void     connection_do_close           (LmConnection          *connection);

static gboolean connection_in_event          (GIOChannel   *source,

					      GIOCondition  condition,

					      LmConnection *connection);

static gboolean connection_error_event       (GIOChannel   *source,

					      GIOCondition  condition,

					      LmConnection *connection);

static gboolean connection_hup_event         (GIOChannel   *source,

					      GIOCondition  condition,

					      LmConnection *connection);

static gboolean connection_send              (LmConnection             *connection,

					      const gchar          *str,

					      gint                  len,

					      GError               **error);

static LmMessage *     connection_create_auth_req_msg (const gchar *username);

static LmMessage *     connection_create_auth_msg     (LmConnection *connection,

						       const gchar  *username,

						       const gchar  *password,

						       const gchar  *resource,

						       gint          auth_type);

static LmHandlerResult connection_auth_req_reply (LmMessageHandler *handler,

						  LmConnection     *connection,

						  LmMessage        *m,

						  gpointer          user_data);

static int connection_check_auth_type   (LmMessage           *auth_req_rpl);

static LmHandlerResult connection_auth_reply (LmMessageHandler    *handler,

					      LmConnection        *connection,

					      LmMessage           *m,

					      gpointer             user_data);

static void     connection_stream_received   (LmConnection             *connection, 

					      LmMessage                *m);

static gint     connection_handler_compare_func (HandlerData  *a,

						 HandlerData  *b);

static gboolean connection_incoming_prepare  (GSource         *source,

					      gint            *timeout);

static gboolean connection_incoming_check    (GSource         *source);

static gboolean connection_incoming_dispatch (GSource         *source,

					      GSourceFunc      callback,

					      gpointer           user_data);

static GSource * connection_create_source    (LmConnection *connection);

static void      connection_signal_disconnect (LmConnection *connection,

					       LmDisconnectReason reason);

static GSourceFuncs incoming_funcs = {

	connection_incoming_prepare,

	connection_incoming_check,

	connection_incoming_dispatch,

	NULL

};

static void

connection_free (LmConnection *connection)

{

	g_free (connection->server);

	if (connection->io_channel) {

		connection_do_close (connection);

	}

	g_free (connection);

}

static void

connection_handle_message (LmConnection *connection, LmMessage *m)

{

	LmMessageHandler *handler;

	GSList           *l;

	const gchar      *id;

	LmHandlerResult   result = LM_HANDLER_RESULT_ALLOW_MORE_HANDLERS;

	if (lm_message_get_type (m) == LM_MESSAGE_TYPE_STREAM) {

		connection_stream_received (connection, m);

		return;

	}

	id = lm_message_node_get_attribute (m->node, "id");

	if (id) {

		handler = g_hash_table_lookup (connection->id_handlers, id);

		if (handler) {

			result = _lm_message_handler_handle_message (handler, 

								     connection,

								     m);

			g_hash_table_remove (connection->id_handlers, id);

		}

	}

	if (result == LM_HANDLER_RESULT_REMOVE_MESSAGE) {

		return;

	}

	for (l = connection->handlers[lm_message_get_type (m)]; 

	     l && result == LM_HANDLER_RESULT_ALLOW_MORE_HANDLERS; 

	     l = l->next) {

		HandlerData *hd = (HandlerData *) l->data;

		result = _lm_message_handler_handle_message (hd->handler,

							     connection,

							     m);

	}

	return;

}

static void

connection_new_message_cb (LmParser     *parser,

			   LmMessage    *m,

			   LmConnection *connection)

{

	lm_message_ref (m);

	lm_verbose ("New message with type=\"%s\" from: %s\n",

		    _lm_message_type_to_string (lm_message_get_type (m)),

		    lm_message_node_get_attribute (m->node, "from"));

	g_queue_push_tail (connection->incoming_messages, m);

}

static gboolean

connection_do_open (LmConnection *connection, GError **error)

{

	struct hostent     *he;

        struct in_addr     *haddr;

        struct sockaddr_in  saddr;

	gint                fd;

	g_return_val_if_fail (connection != NULL, FALSE);

        he = gethostbyname(connection->server);

        if (he == NULL) {

 		g_set_error (error,

 			     LM_ERROR,                 

 			     LM_ERROR_CONNECTION_OPEN,   

 			     "gethostbyname() failed");

		return FALSE;

        }

        haddr = ((struct in_addr *) (he->h_addr_list)[0]);

#ifdef HAVE_GNUTLS

	if (connection->use_ssl) {

		gnutls_global_init ();

		gnutls_certificate_allocate_credentials(&connection->gnutls_xcred);

	}

#endif

	fd = socket(AF_INET, SOCK_STREAM, 0);

	memset(&saddr, 0, sizeof(saddr));

	memcpy(&saddr.sin_addr, haddr, sizeof(struct in_addr));

	saddr.sin_family = AF_INET;

	saddr.sin_port = htons (connection->port);

        if (connect(fd, (struct sockaddr *)&saddr, sizeof(saddr)) < 0) {

		g_set_error (error,

 			     LM_ERROR,           

 			     LM_ERROR_CONNECTION_OPEN,

 			     "connect() failed");

		close (fd);

		return FALSE;

        }

#ifdef HAVE_GNUTLS

	if (connection->use_ssl) {

		int ret;

		const int cert_type_priority[2] =

		{ GNUTLS_CRT_X509, GNUTLS_CRT_OPENPGP };

		gnutls_init (&connection->gnutls_session, GNUTLS_CLIENT);

		gnutls_set_default_priority (connection->gnutls_session);

		gnutls_certificate_type_set_priority (connection->gnutls_session,

						      cert_type_priority);

		gnutls_credentials_set (connection->gnutls_session,

					GNUTLS_CRD_CERTIFICATE,

					connection->gnutls_xcred);

		gnutls_transport_set_ptr (connection->gnutls_session, 

					  (gnutls_transport_ptr) fd);

		ret = gnutls_handshake (connection->gnutls_session);

		if (ret < 0) {

			gnutls_perror (ret);

			shutdown (fd, SHUT_RDWR);

			close (fd);

			connection_do_close (connection);

			g_set_error (error, LM_ERROR, LM_ERROR_CONNECTION_OPEN,

				     "*** GNUTLS handshake failed");

			return FALSE;

		}

	}

#endif

	connection->io_channel = g_io_channel_unix_new (fd);

	g_io_channel_set_close_on_unref (connection->io_channel, TRUE);

	g_io_channel_set_encoding (connection->io_channel, NULL, NULL);

	g_io_channel_set_buffered (connection->io_channel, FALSE);

	g_io_channel_set_flags (connection->io_channel,

				G_IO_FLAG_NONBLOCK, NULL);

	connection->io_watch_in = g_io_add_watch (connection->io_channel,

						  G_IO_IN,

						  (GIOFunc) connection_in_event,

						  connection);

	connection->io_watch_err = g_io_add_watch (connection->io_channel, 

						   G_IO_ERR,

						   (GIOFunc) connection_error_event,

						   connection);

	connection->io_watch_hup = g_io_add_watch (connection->io_channel,

						   G_IO_HUP,

						   (GIOFunc) connection_hup_event,

						   connection);

	connection->is_open = TRUE;

	if (!connection_send (connection,

			      "<?xml version='1.0' encoding='UTF-8'?>", -1, 

			      error)) {

		return FALSE;

	}

	return TRUE;

}

static void

connection_do_close (LmConnection *connection)

{

	if (connection->io_channel) {

		g_source_remove (connection->io_watch_in);

		g_source_remove (connection->io_watch_err);

		g_source_remove (connection->io_watch_hup);

		g_io_channel_unref (connection->io_channel);

		connection->io_channel = NULL;

	} 

	if (!connection->is_open) {

		return;

	}

	connection->is_open = FALSE;

#ifdef HAVE_GNUTLS

	if (connection->use_ssl) {

		gnutls_deinit (connection->gnutls_session);

		gnutls_certificate_free_credentials (connection->gnutls_xcred);

		gnutls_global_deinit ();

	}

#endif

}

static gboolean

connection_in_event (GIOChannel   *source,

		     GIOCondition  condition,

		     LmConnection *connection)

{

	gchar     buf[IN_BUFFER_SIZE];

	GIOStatus status;

	if (!connection->io_channel) {

		return FALSE;

	}

#ifdef HAVE_GNUTLS

	if (connection->use_ssl) {

		bytes_read = gnutls_record_recv (connection->gnutls_session,

						 buf,IN_BUFFER_SIZE - 1);

		if (bytes_read <= 0) {

			status = G_IO_STATUS_ERROR;

			//connection_error_event (connection->io_channel, 

			//			G_IO_HUP,

			//			connection);

		}

		else {

			status = G_IO_STATUS_NORMAL;

		}

	} else {

#endif

	    status = g_io_channel_read_chars (connection->io_channel,

					      buf, IN_BUFFER_SIZE - 1,

					      &bytes_read,

					      NULL);

#ifdef HAVE_GNUTLS

	}

#endif

	if (status != G_IO_STATUS_NORMAL) {

		gint reason;

		switch (status) {

		case G_IO_STATUS_EOF:

			reason = LM_DISCONNECT_REASON_HUP;

			break;

		case G_IO_STATUS_AGAIN:

			return TRUE;

			break;

		case G_IO_STATUS_ERROR:

			reason = LM_DISCONNECT_REASON_ERROR;

			break;