/*

 * Copyright (C) 2008 Imendio 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>

#include <string.h>

#include <asyncns.h>

#define freeaddrinfo(x) asyncns_freeaddrinfo(x)

/* Needed on Mac OS X */

#if HAVE_ARPA_NAMESER_COMPAT_H

#include <arpa/nameser_compat.h>

#endif

#include <arpa/nameser.h>

#include <resolv.h>

#include "lm-error.h"

#include "lm-internals.h"

#include "lm-marshal.h"

#include "lm-misc.h"

#include "lm-asyncns-resolver.h"

#define GET_PRIV(obj) (G_TYPE_INSTANCE_GET_PRIVATE ((obj), LM_TYPE_ASYNCNS_RESOLVER, LmAsyncnsResolverPriv))

typedef struct LmAsyncnsResolverPriv LmAsyncnsResolverPriv;

struct LmAsyncnsResolverPriv {

	GSource		*watch_resolv;

	asyncns_query_t *resolv_query;

	asyncns_t	*asyncns_ctx;

	GIOChannel	*resolv_channel;

};

static void     asyncns_resolver_finalize      (GObject     *object);

static void     asyncns_resolver_lookup        (LmResolver  *resolver);

static void     asyncns_resolver_cancel        (LmResolver  *resolver);

G_DEFINE_TYPE (LmAsyncnsResolver, lm_asyncns_resolver, LM_TYPE_RESOLVER)

static void

lm_asyncns_resolver_class_init (LmAsyncnsResolverClass *class)

{

	GObjectClass    *object_class = G_OBJECT_CLASS (class);

        LmResolverClass *resolver_class = LM_RESOLVER_CLASS (class);

	object_class->finalize = asyncns_resolver_finalize;

        resolver_class->lookup = asyncns_resolver_lookup;

        resolver_class->cancel = asyncns_resolver_cancel;

	g_type_class_add_private (object_class, sizeof (LmAsyncnsResolverPriv));

}

static void

lm_asyncns_resolver_init (LmAsyncnsResolver *asyncns_resolver)

{

	LmAsyncnsResolverPriv *priv;

	priv = GET_PRIV (asyncns_resolver);

}

static void

asyncns_resolver_finalize (GObject *object)

{

	LmAsyncnsResolverPriv *priv;

	priv = GET_PRIV (object);

	(G_OBJECT_CLASS (lm_asyncns_resolver_parent_class)->finalize) (object);

}

static void

asyncns_resolver_cleanup (LmResolver *resolver)

{

        LmAsyncnsResolverPriv *priv = GET_PRIV (resolver);

        if (priv->resolv_channel != NULL) {

		g_io_channel_unref (priv->resolv_channel);

                priv->resolv_channel = NULL;

	}

        if (priv->watch_resolv) {

		g_source_destroy (priv->watch_resolv);

                priv->watch_resolv = NULL;

	}

	if (priv->asyncns_ctx) {

                asyncns_free (priv->asyncns_ctx);

                priv->asyncns_ctx = NULL;

	}

        priv->resolv_query = NULL;

}

static void

asyncns_resolver_done (LmResolver *resolver)

{

        LmAsyncnsResolverPriv *priv = GET_PRIV (resolver);

        struct addrinfo	      *ans;

	int 		       err;

        err = asyncns_getaddrinfo_done (priv->asyncns_ctx, priv->resolv_query, &ans);

        priv->resolv_query = NULL;

        /* Signal that we are done */

        g_object_ref (resolver);

        if (err) {

                _lm_resolver_set_result (resolver,

                                         LM_RESOLVER_RESULT_FAILED, 

                                         NULL);

        } else {

                _lm_resolver_set_result (resolver,

                                         LM_RESOLVER_RESULT_OK,

                                         ans);

        }

        asyncns_resolver_cleanup (resolver);

        g_object_unref (resolver);

}

typedef gboolean  (* LmAsyncnsResolverCallback) (LmResolver *resolver);

static gboolean

asyncns_resolver_io_cb (GSource      *source,

                        GIOCondition  condition,

                        LmResolver   *resolver)

{

        LmAsyncnsResolverPriv     *priv = GET_PRIV (resolver);

        LmAsyncnsResolverCallback  func;

        asyncns_wait (priv->asyncns_ctx, FALSE);

        if (!asyncns_isdone (priv->asyncns_ctx, priv->resolv_query)) {

                return TRUE;

        }

        func = (LmAsyncnsResolverCallback) asyncns_getuserdata (priv->asyncns_ctx,

                                                                priv->resolv_query);

        return func (resolver);

}

static gboolean

asyncns_resolver_prep (LmResolver *resolver, GError **error)

{

        LmAsyncnsResolverPriv *priv = GET_PRIV (resolver);

        GMainContext          *context;

        if (priv->asyncns_ctx) {

                return TRUE;

	}

        priv->asyncns_ctx = asyncns_new (1);

	if (priv->asyncns_ctx == NULL) {

                g_set_error (error,

                             LM_ERROR,                 

                             LM_ERROR_CONNECTION_FAILED,   

                             "can't initialise libasyncns");

		return FALSE;

	}

        priv->resolv_channel =

                g_io_channel_unix_new (asyncns_fd (priv->asyncns_ctx));

        g_object_get (resolver, "context", &context, NULL);

        g_print ("Setting up io watch\n");

        priv->watch_resolv = 

                lm_misc_add_io_watch (context,

                                      priv->resolv_channel,

				      G_IO_IN,

                                      (GIOFunc) asyncns_resolver_io_cb,

                                      resolver);

	return TRUE;

}

static void

asyncns_resolver_lookup_host (LmResolver *resolver)

{

        LmAsyncnsResolverPriv *priv = GET_PRIV (resolver);

        gchar               *host;

        struct addrinfo      req;

        g_object_get (resolver, "host", &host, NULL);

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

	req.ai_family   = AF_UNSPEC;

	req.ai_socktype = SOCK_STREAM;

	req.ai_protocol = IPPROTO_TCP;

	if (!asyncns_resolver_prep (resolver, NULL)) {

                g_warning ("Signal error\n");

		return;

        }

        priv->resolv_query =

	  	asyncns_getaddrinfo (priv->asyncns_ctx,

                                     host,

				     NULL,

				     &req);

	asyncns_setuserdata (priv->asyncns_ctx,

                             priv->resolv_query,

			     (gpointer) asyncns_resolver_done);

}

static void

asyncns_resolver_srv_done (LmResolver *resolver)

{

        LmAsyncnsResolverPriv *priv = GET_PRIV (resolver);

        unsigned char         *srv_ans;

	int 		       srv_len;

        gboolean               result = FALSE;

        g_print ("srv_done callback\n");

        srv_len = asyncns_res_done (priv->asyncns_ctx, 

                                    priv->resolv_query, &srv_ans);

        priv->resolv_query = NULL;

        if (srv_len <= 0) {

                /* FIXME: Report error */

                g_warning ("Failed to read srv request results");

        } else {

                gchar *new_server;

                guint  new_port;

                g_print ("trying to parse srv response\n");

                result = _lm_resolver_parse_srv_response (srv_ans, srv_len,

                                                          &new_server,

                                                          &new_port);

                if (result == TRUE) {

                        g_print ("worked, new host/post is %s/%d\n",

                                 new_server, new_port);

                        g_object_set (resolver,

                                      "host", new_server,

                                      "port", new_port,

                                      NULL);

                }

                g_free (new_server);

                /* TODO: Check whether srv_ans needs freeing */

        }

        asyncns_resolver_cleanup (resolver);

        if (result == TRUE) {

                asyncns_resolver_lookup_host (resolver);

        }

}

static void

asyncns_resolver_lookup_service (LmResolver *resolver)

{

        LmAsyncnsResolverPriv *priv = GET_PRIV (resolver);

        gchar                 *domain;

        gchar                 *service;

        gchar                 *protocol;

        gchar                 *srv;

        g_object_get (resolver,

                      "domain", &domain,

                      "service", &service,

                      "protocol", &protocol,

                      NULL);

        srv = _lm_resolver_create_srv_string (domain, service, protocol);

        g_print ("Looking up service: %s %s %s\n[%s]", domain, service, protocol, srv);

        if (!asyncns_resolver_prep (resolver, /* Use GError? */ NULL)) {

                g_warning ("Failed to initiate the asyncns library");

                /* FIXME: Signal error */

                return;

        }

        priv->resolv_query =

                asyncns_res_query (priv->asyncns_ctx, srv, C_IN, T_SRV);

        asyncns_setuserdata (priv->asyncns_ctx, 

                             priv->resolv_query, 

                             (gpointer) asyncns_resolver_srv_done);

        g_free (srv);

        g_free (domain);

        g_free (service);

        g_free (protocol);

}

static void

asyncns_resolver_lookup (LmResolver *resolver)

{

        gint type;

        /* Start the DNS querying */

        /* Decide if we are going to lookup a srv or host */

        g_object_get (resolver, "type", &type, NULL);

        switch (type) {

        case LM_RESOLVER_HOST:

                asyncns_resolver_lookup_host (resolver);

                break;

        case LM_RESOLVER_SRV:

                asyncns_resolver_lookup_service (resolver);

                break;

        };

        /* End of DNS querying */

} 

static void

asyncns_resolver_cancel (LmResolver *resolver)

{

        LmAsyncnsResolverPriv *priv;

        g_return_if_fail (LM_IS_ASYNCNS_RESOLVER (resolver));

        priv = GET_PRIV (resolver);

        if (priv->asyncns_ctx) {

                if (priv->resolv_query) {

                        asyncns_cancel (priv->asyncns_ctx, priv->resolv_query);

                        priv->resolv_query = NULL;

                }

                _lm_resolver_set_result (resolver,

                                         LM_RESOLVER_RESULT_CANCELLED,

                                         NULL);

        }

}