/* ulogd_PGSQL.c, Version $Revision$
 *
 * ulogd output plugin for logging to a PGSQL database
 *
 * (C) 2000-2005 by Harald Welte <laforge@gnumonks.org> 
 * This software is distributed under the terms of GNU GPL 
 * 
 * This plugin is based on the MySQL plugin made by Harald Welte.
 * The support PostgreSQL were made by Jakab Laszlo.
 *
 */

#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <arpa/inet.h>
#include <libpq-fe.h>
#include <ulogd/ulogd.h>
#include <ulogd/conffile.h>

#include "../../utils/db.c"

#ifdef DEBUG_PGSQL
#define DEBUGP(x, args...)	fprintf(stderr, x, ## args)
#else
#define DEBUGP(x, args...)
#endif

struct pgsql_instance {
	struct db_instance db_inst;

	PGconn *dbh;
	PGresult *pgres;
	unsigned char pgsql_have_schemas;
}
#define TIME_ERR	((time_t)-1)

/* our configuration directives */
static struct config_keyset pgsql_kset = {
	.num_ces = DB_CE_NUM + 6,
	.ces = {
		DB_CES,
		{ 
			.key = "db", 
			.type = CONFIG_TYPE_STRING,
			.options = CONFIG_OPT_MANDATORY,
		},
		{
			.key = "host", 
			.type = CONFIG_TYPE_STRING,
			.options = CONFIG_OPT_NONE,
		},
		{ 
			.key = "user", 
			.type = CONFIG_TYPE_STRING,
			.options = CONFIG_OPT_MANDATORY,
		},
		{
			.key = "pass", 
			.type = CONFIG_TYPE_STRING,
			.options = CONFIG_OPT_NONE,
		},
		{
			.next = &schema_ce,
			.key = "port",
			.type = CONFIG_TYPE_INT,
		},
		{
			.key = "schema", 
			.type = CONFIG_TYPE_STRING,
			.u.string = "public",
		},
	},
};
#define db_ce(x)	(x->ces[DB_CE_NUM+0])
#define host_ce(x)	(x->ces[DB_CE_NUM+1])
#define user_ce(x)	(x->ces[DB_CE_NUM+2])
#define pass_ce(x)	(x->ces[DB_CE_NUM+3])
#define port_ce(x)	(x->ces[DB_CE_NUM+5])
#define schema_ce(x)	(x->ces[DB_CE_NUM+6])

#if 0
/* our main output function, called by ulogd */
static int pgsql_output(ulog_iret_t *result)
{
	struct _field *f;
	ulog_iret_t *res;
	PGresult   *pgres;
#ifdef IP_AS_STRING
	char *tmpstr;		/* need this for --log-ip-as-string */
	struct in_addr addr;
#endif

	stmt_ins = stmt_val;

	for (f = fields; f; f = f->next) {
		res = keyh_getres(f->id);

		if (!res) {
			ulogd_log(ULOGD_NOTICE,
				"no result for %s ?!?\n", f->name);
		}

		if (!res || !IS_VALID((*res))) {
			/* no result, we have to fake something */
			sprintf(stmt_ins, "NULL,");
			stmt_ins = stmt + strlen(stmt);
			continue;
		}

		switch (res->type) {
			case ULOGD_RET_INT8:
				sprintf(stmt_ins, "%d,", res->value.i8);
				break;
			case ULOGD_RET_INT16:
				sprintf(stmt_ins, "%d,", res->value.i16);
				break;
			case ULOGD_RET_INT32:
				sprintf(stmt_ins, "%d,", res->value.i32);
				break;
			case ULOGD_RET_INT64:
				sprintf(stmt_ins, "%lld,", res->value.i64);
				break;
			case ULOGD_RET_UINT8:
				sprintf(stmt_ins, "%u,", res->value.ui8);
				break;
			case ULOGD_RET_UINT16:
				sprintf(stmt_ins, "%u,", res->value.ui16);
				break;
			case ULOGD_RET_IPADDR:
#ifdef IP_AS_STRING
				*stmt_ins++ = '\'';
				memset(&addr, 0, sizeof(addr));
				addr.s_addr = ntohl(res->value.ui32);
				tmpstr = (char *)inet_ntoa(addr);
				PQescapeString(stmt_ins,tmpstr,strlen(tmpstr)); 
				stmt_ins = stmt + strlen(stmt);
				sprintf(stmt_ins, "',");
				break;
#endif /* IP_AS_STRING */
				/* EVIL: fallthrough when logging IP as
				 * u_int32_t */

			case ULOGD_RET_UINT32:
				sprintf(stmt_ins, "%u,", res->value.ui32);
				break;
			case ULOGD_RET_UINT64:
				sprintf(stmt_ins, "%llu,", res->value.ui64);
				break;
			case ULOGD_RET_BOOL:
				sprintf(stmt_ins, "'%d',", res->value.b);
				break;
			case ULOGD_RET_STRING:
				*stmt_ins++ = '\'';
				PQescapeString(stmt_ins,res->value.ptr,strlen(res->value.ptr)); 
				stmt_ins = stmt + strlen(stmt);
				sprintf(stmt_ins, "',");
				break;
			case ULOGD_RET_RAW:
				ulogd_log(ULOGD_NOTICE,"%s: pgsql doesn't support type RAW\n",res->key);
				sprintf(stmt_ins, "NULL,");
				break;
			default:
				ulogd_log(ULOGD_NOTICE,
					"unknown type %d for %s\n",
					res->type, res->key);
				break;
		}
		stmt_ins = stmt + strlen(stmt);
	}
	*(stmt_ins - 1) = ')';
	DEBUGP("stmt=#%s#\n", stmt);

	/* now we have created our statement, insert it */
	/* Added code by Jaki */
	pgres = PQexec(dbh, stmt);
	if(!pgres || PQresultStatus(pgres) != PGRES_COMMAND_OK) {
		ulogd_log(ULOGD_ERROR, "sql error during insert: %s\n",
				PQresultErrorMessage(pgres));
		return 1;
	}

	return 0;
}
#endif

#define PGSQL_HAVE_NAMESPACE_TEMPLATE "SELECT nspname FROM pg_namespace n WHERE n.nspname='%s'"

/* Determine if server support schemas */
static int pgsql_namespace(void)
{
	PGresult *result;
	char pgbuf[strlen(PGSQL_HAVE_NAMESPACE_TEMPLATE)+strlen(schema_ce.u.string)+1];

	if (!dbh)
		return 1;

	sprintf(pgbuf, PGSQL_HAVE_NAMESPACE_TEMPLATE, schema_ce.u.string);
	ulogd_log(ULOGD_DEBUG, "%s\n", pgbuf);
	
	result = PQexec(dbh, pgbuf);
	if (!result) {
		ulogd_log(ULOGD_DEBUG, "\n result false");
		return 1;
	}

	if (PQresultStatus(result) == PGRES_TUPLES_OK) {
		ulogd_log(ULOGD_DEBUG, "using schema %s\n", schema_ce.u.string);
		pgsql_have_schemas = 1;
	} else {
		pgsql_have_schemas = 0;
	}

	PQclear(result);
	
	return 0;
}

#define PGSQL_GETCOLUMN_TEMPLATE "SELECT  a.attname FROM pg_class c, pg_attribute a WHERE c.relname ='%s' AND a.attnum>0 AND a.attrelid=c.oid ORDER BY a.attnum"

#define PGSQL_GETCOLUMN_TEMPLATE_SCHEMA "SELECT a.attname FROM pg_attribute a, pg_class c LEFT JOIN pg_namespace n ON c.relnamespace=n.oid WHERE c.relname ='%s' AND n.nspname='%s' AND a.attnum>0 AND a.attrelid=c.oid AND a.attisdropped=FALSE ORDER BY a.attnum"

/* find out which columns the table has */
static int get_columns_pgsql(struct ulogd_pluginstance *upi)
{
	struct pgsql_instance *pi = (struct pgsql_instance *) upi->private;
	PGresult *result;
	char pgbuf[strlen(PGSQL_GETCOLUMN_TEMPLATE_SCHEMA)
		   + strlen(table) + strlen(schema_ce.u.string) + 2];
	int intaux;

	if (!pi->dbh) {
		ulogd_log(ULOGD_ERROR, "no database handle\n");
		return 1;
	}

	if (pgsql_have_schemas) {
		snprintf(pgbuf, sizeof(pgbuf)-1, PGSQL_GETCOLUMN_TEMPLATE_SCHEMA,
			 table_ce(upi->config_kset).u.string,
			 schema_ce(upi->config_kset).u.string);
	} else {
		snprintf(pgbuf, sizeof(pgbuf)-1, PGSQL_GETCOLUMN_TEMPLATE,
			 table_ce(upi->config_kset).u.string);
	}

	ulogd_log(ULOGD_DEBUG, "%s\n", pgbuf);

	result = PQexec(dbh, pgbuf);
	if (!result) {
		ulogd_log(ULOGD_DEBUG, "result false");
		return -1;
	}

	if (PQresultStatus(result) != PGRES_TUPLES_OK) {
		ulogd_log(ULOGD_DEBUG, "pres_command_not_ok");
		return -1;
	}

	if (upi->input.keys)
		free(upi->input.keys);

	upi->input.num_keys = PQntuples(result);
	ulogd_log(ULOGD_DEBUG, "%u fields in table\n", upi->input.num_keys);
	upi->input.keys = malloc(sizeof(struct ulogd_key) *
						upi->input.num_keys);
	if (!upi->input.keys) {
		upi->input.num_keys = 0;
		ulogd_log(ULOGD_ERROR, "ENOMEM\n");
		return -ENOMEM;
	}

	memset(upi->input.keys, 0, sizeof(struct ulogd_key) *
						upi->input.num_keys);

	for (intaux = 0; intaux < PQntuples(result); intaux++) {
		char buf[ULOGD_MAX_KEYLEN+1];
		char *underscore;
		int id;

		/* replace all underscores with dots */
		strncpy(buf, PQgetvalue(result, intaux, 0), ULOGD_MAX_KEYLEN);
		while ((underscore = strchr(buf, '_')))
			*underscore = '.';

		DEBUGP("field '%s' found: ", buf);

		/* add it to list of input keys */
		strncpy(upi->input.keys[i].name, buf, ULOGD_MAX_KEYLEN);
	}

	/* FIXME: id? */

	PQclear(result);
	return 0;
}

static int close_db_pgsql(struct ulogd_pluginstance *upi)
{
	struct pgsql_instance *pi = (struct pgsql_instance *) upi->private;

	return PQfinish(pi->dbh);
}

/* make connection and select database */
static int open_db_pgsql(struct ulogd_pluginstance *upi)
{
	struct pgsql_instance *pi = (struct pgsql_instance *) upi->private;
	int len;
	char *connstr;
	char *server = host_ce(upi->config_kset).u.string;
	char *port = port_ce(upi->config_kset).u.string;
	char *user = user_ce(upi->config_kset).u.string;
	char *pass = pass_ce(upi->config_kset).u.string;
	char *db = db_ce(upi->config_kset).u.string;

	/* 80 is more than what we need for the fixed parts below */
	len = 80 + strlen(user) + strlen(db);

	/* hostname and  and password are the only optionals */
	if (server)
		len += strlen(server);
	if (pass)
		len += strlen(pass);
	if (port)
		len += 20;

	connstr = (char *) malloc(len);
	if (!connstr) 
		return -ENOMEM;

	if (server) {
		strcpy(connstr, " host=");
		strcat(connstr, server);
	}

	if (port) {
		char portbuf[20];
		snprintf(portbuf, sizeof(portbuf), " port=%u", port);
		strcat(connstr, portbuf);
	}

	strcat(connstr, " dbname=");
	strcat(connstr, db);
	strcat(connstr, " user=");
	strcat(connstr, user);

	if (pass) {
		strcat(connstr, " password=");
		strcat(connstr, pass);
	}
	
	dbh = PQconnectdb(connstr);
	if (PQstatus(dbh) != CONNECTION_OK) {
		close_db(upi);
		return -1;
	}

	if (pgsql_namespace()) {
		ulogd_log(ULOGD_ERROR, "unable to test for pgsql schemas\n");
		close_db(upi);
		return -1;
	}

	return 0;
}

static int escape_string_pgsql(struct ulogd_pluginstance *upi,
			       char *dst, const char *src, unsigned int len)
{
	PQescapeString(dst, src, strlen(res->value.ptr)); 
	return 0;
}

static int execute_pgsql(struct ulogd_pluginstance *upi,
			 const char *stmt, unsigned int len)
{
	struct pgsql_instance *pi = (struct pgsql_instance *) upi->private;

	pi->pgres = PQexec(dbh, stmt);
	if (!pi->pgres || PQresultStatus(pi->pgres) != PGRES_COMMAND_OK)
		return -1;

	return 0;
}

static char *strerror_pgsql(struct ulogd_pluginstance *upi)
{
	struct pgsql_instance *pi = (struct pgsql_instance *) upi->private;
	return PQresultErrorMessage(pi->pgres);
}

static struct db_driver db_driver_pgsql = {
	.get_columns	= &get_columns_pgsql,
	.open_db	= &open_db_pgsql,
	.close_db	= &close_db_pgsql,
	.escape_string	= &escape_string_pgsql,
	.execute	= &execute_pgsql,
	.strerror	= &strerror_pgsql,
};

static int configure_pgsql(struct ulogd_pluginstance *upi,
			   struct ulogd_pluginstance_stack *stack)
{
	struct pgsql_instance *pi = (struct pgsql_instance *) upi->private;

	di->driver = &db_driver_pgsql;

	return configure_db(upi, stack);
}

static struct ulogd_plugin pgsql_plugin = { 
	.name 		= "PGSQL", 
	.input 		= {
		.keys	= NULL,
		.num_keys = 0,
		.type	= ULOGD_DTYPE_PACKET | ULOGD_DTYPE_FLOW,
	},
	.output 	= {
		.type	= ULOGD_DTYPE_SINK,
	},
	.config_kset 	= &pgsql_kset,
	.priv_size	= sizeof(struct pgsql_instance),
	.start		= &start_pgsql,
	.stop		= &stop_db,
	.signal		= &signal_db,
	.interp		= &interp_pgsql,
	.version	= ULOGD_VERSION,
};

void __attribute__ ((constructor)) init(void);

void _init(void)
{
	ulogd_register_plugin(&pgsql_plugin);
}