/*-
 * Copyright 2016 Vsevolod Stakhov
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#include "config.h"

#include "libutil/util.h"
#include "libserver/cfg_file.h"
#include "libserver/cfg_rcl.h"
#include "libserver/worker_util.h"
#include "libserver/rspamd_control.h"
#include "libutil/addr.h"
#include "unix-std.h"

#ifdef HAVE_GLOB_H
#include <glob.h>
#endif

static gpointer init_log_helper (struct rspamd_config *cfg);
static void start_log_helper (struct rspamd_worker *worker);

worker_t log_helper_worker = {
		"log_helper",                /* Name */
		init_log_helper,             /* Init function */
		start_log_helper,            /* Start function */
		RSPAMD_WORKER_UNIQUE | RSPAMD_WORKER_KILLABLE,
		SOCK_STREAM,                /* TCP socket */
		RSPAMD_WORKER_VER           /* Version info */
};

static const guint64 rspamd_log_helper_magic = 0x1090bb46aaa74c9aULL;

/*
 * Worker's context
 */
struct log_helper_ctx {
	guint64 magic;
	struct rspamd_config *cfg;
	struct event_base *ev_base;
	struct event log_ev;
	gint pair[2];
};

static gpointer
init_log_helper (struct rspamd_config *cfg)
{
	struct log_helper_ctx *ctx;
	GQuark type;

	type = g_quark_try_string ("log_helper");
	ctx = g_malloc0 (sizeof (*ctx));

	ctx->magic = rspamd_log_helper_magic;
	ctx->cfg = cfg;

	return ctx;
}

static void
rspamd_log_helper_read (gint fd, short what, gpointer ud)
{
	struct log_helper_ctx *ctx = ud;
	guchar buf[1024];
	gssize r;
	guint32 n, i;
	struct rspamd_protocol_log_message_sum *sm;
	GString *out;

	r = read (fd, buf, sizeof (buf));

	if (r >= (gssize)sizeof (struct rspamd_protocol_log_message_sum)) {
		memcpy (&n, buf, sizeof (n));

		if (n != (r - sizeof (guint32)) / sizeof (guint32)) {
			msg_warn ("cannot read data from log pipe: bad length: %d elements "
					"announced but %d available", n,
					(r - sizeof (guint32)) / sizeof (guint32));
		}
		else {
			sm = g_malloc (r);
			memcpy (sm, buf, r);
			out = g_string_sized_new (31);

			for (i = 0; i < n; i ++) {
				rspamd_printf_gstring (out, "%s%d", i == 0 ? "" : ", ",
						sm->results[i]);
			}

			msg_info ("got log line: %V", out);
			g_string_free (out, TRUE);
			g_free (sm);
		}
	}
	else if (r == -1) {
		msg_warn ("cannot read data from log pipe: %s", strerror (errno));
	}
}

static void
rspamd_log_helper_reply_handler (struct rspamd_worker *worker,
		struct rspamd_srv_reply *rep, gint rep_fd,
		gpointer ud)
{
	struct log_helper_ctx *ctx = ud;

	close (ctx->pair[1]);
	event_set (&ctx->log_ev, ctx->pair[0], EV_READ | EV_PERSIST,
			rspamd_log_helper_read, ctx);
	event_base_set (ctx->ev_base, &ctx->log_ev);
	event_add (&ctx->log_ev, NULL);
}

static void
start_log_helper (struct rspamd_worker *worker)
{
	struct log_helper_ctx *ctx = worker->ctx;
	gssize r = -1;
	static struct rspamd_srv_command srv_cmd;

	ctx->ev_base = rspamd_prepare_worker (worker,
			"log_helper",
			NULL);

#ifdef HAVE_SOCK_SEQPACKET
	r = socketpair (AF_LOCAL, SOCK_SEQPACKET, 0, ctx->pair);
#endif
	if (r == -1 && socketpair (AF_LOCAL, SOCK_DGRAM, 0, ctx->pair) == -1) {
		msg_err ("cannot create socketpair: %s, exiting now", strerror (errno));
		/* Prevent new processes spawning */
		exit (EXIT_SUCCESS);
	}

	srv_cmd.type = RSPAMD_SRV_LOG_PIPE;
	srv_cmd.cmd.log_pipe.type = RSPAMD_LOG_PIPE_SYMBOLS;

	rspamd_srv_send_command (worker, ctx->ev_base, &srv_cmd, ctx->pair[1],
			rspamd_log_helper_reply_handler, ctx);
	event_base_loop (ctx->ev_base, 0);
	close (ctx->pair[0]);
	rspamd_worker_block_signals ();

	rspamd_log_close (worker->srv->logger);

	exit (EXIT_SUCCESS);
}