/*
 * PostgreSQL plugin. 
 * $Id$
 */

#define IN_PLUGIN
#include "../../echoping.h"

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#ifdef POSTGRESQL_PREFIX
#include <postgresql/libpq-fe.h>
#else
#include <libpq-fe.h>
#endif

const char     *request = NULL;
int             readall = FALSE;
int             connect_each_time = FALSE;
poptContext     postgresql_poptcon;
PGconn         *conn;
PGresult       *res;
char           *conninfo;
echoping_options global_options;

void
postgresql_usage(const char *msg)
{
	if (msg) {
		printf("PostgreSQL plugin error: %s\n", msg);
	}
	poptPrintUsage(postgresql_poptcon, stdout, 0);
	fprintf(stderr, "  [SQL-request]\n");
	exit(1);
}

char           *
init(const int argc, const char **argv,
     const echoping_options global_external_options)
{
	int             value;
	char           *msg = malloc(256);
	char           *rest;
	/* popt variables */
	struct poptOption options[] = {
		{"conninfo", 'c', POPT_ARG_STRING, &conninfo, 0,
		 "Connection information for the Postgresql server. Something like 'host=foo dbname=bar''",
		 ""},
		{"readall", 'a', POPT_ARG_NONE, &readall, 0,
		 "Read all the data sent by the Postgresql server",
		 ""},
		{"connect-each-time", 'e', POPT_ARG_NONE, &connect_each_time, 0,
		 "(Re)Connect to the Postgresql server at each iteration",
		 ""},
		POPT_AUTOHELP POPT_TABLEEND
	};
	global_options = global_external_options;
	if (global_options.udp)
		err_quit("UDP makes no sense for a PostgreSQL connection");
	postgresql_poptcon = poptGetContext(NULL, argc,
					    argv, options,
					    POPT_CONTEXT_POSIXMEHARDER);
	while ((value = poptGetNextOpt(postgresql_poptcon)) > 0) {
	}
	if (value < -1) {
		sprintf(msg, "%s: %s",
			poptBadOption(postgresql_poptcon, POPT_BADOPTION_NOALIAS),
			poptStrerror(value));
		postgresql_usage(msg);
	}
	request = poptGetArg(postgresql_poptcon);
	if (request == NULL)
		request = "SELECT now()";
	rest = poptGetArg(postgresql_poptcon);
	if (rest != NULL)
		postgresql_usage("Erroneous additional arguments");
	if (conninfo == NULL)
		conninfo = "";
	return NULL;		/* We only use the conninfo, echoping does not see
				 * our hostname or port */
}

void
start_raw()
{
	if (!connect_each_time) {
		conn = PQconnectdb(conninfo);
		if (conn == NULL) {
			err_quit("Cannot create connection\n");
		}
		if (PQstatus(conn) == CONNECTION_BAD) {
			err_quit("Connection failed: %s\n", PQerrorMessage(conn));
		}
	}
}

int
execute()
{
	unsigned int    row, column;
	char           *result;
	if (connect_each_time) {
		conn = PQconnectdb(conninfo);
		if (conn == NULL) {
			err_ret("Cannot create connection\n");
			return -1;
		}
		if (PQstatus(conn) == CONNECTION_BAD) {
			err_ret("Connection failed: %s\n", PQerrorMessage(conn));
			return -1;
		}
	}
	res = PQexec(conn, request);
	if (PQresultStatus(res) != PGRES_TUPLES_OK) {
		err_ret("Cannot run \"%s\": %s\n", request,
			PQresultErrorMessage(res));
		return -1;
	}
	if (global_options.verbose)
		printf("%d tuples returned\n", PQntuples(res));
	if (readall) {
		for (row = 0; row < PQntuples(res); row++) {
			for (column = 0; column < PQnfields(res); column++) {
				result = PQgetvalue(res, row, column);
				if (result == NULL) {
					err_ret("Cannot retrieve value [%d,%d]\n",
						row, column);
					return -1;
				}
				/* else { printf ("DEBUG: [%d,%d] %s\n", row,
				 * column, result); } */
			}
		}
	}
	if (connect_each_time)
		PQfinish(conn);
	return 0;
}

void
terminate()
{
	if (!connect_each_time)
		PQfinish(conn);
}