/*
 * src/test/isolation/isolationtester.c
 *
 * isolationtester.c
 *		Runs an isolation test specified by a spec file.
 */

#include <stdio.h>
#include <stdlib.h>
#include <libpq-fe.h>

static void printResultSet(PGresult *res);


static void
exit_nicely(PGconn *conn)
{
    PQfinish(conn);
    exit(1);
}


int
main(int argc, char **argv)
{
    const char *conninfo;
    PGconn     *conn;
	PGresult   *res;

    if (argc > 2)
    {
    	fprintf(stderr, "Usage:  %s connection-string\n", argv[0]);
    	exit(1);
    }
	else if (argc == 2)
        conninfo = argv[1];
    else
        conninfo = "dbname = postgres";

    /* Make a connection to the database */
    conn = PQconnectdb(conninfo);

    /* Check to see that the backend connection was successfully made */
    if (PQstatus(conn) != CONNECTION_OK)
    {
        fprintf(stderr, "Connection to database failed: %s",
                PQerrorMessage(conn));
        exit_nicely(conn);
    }

	res = PQprepare(conn, "prep1", "EXPLAIN SELECT * FROM pg_language", 0, NULL);
	if (PQresultStatus(res) != PGRES_COMMAND_OK)
	{
		fprintf(stderr, "PQprepare() failed: %s", PQerrorMessage(conn));
		exit_nicely(conn);
	}

	PQclear(res);

	res = PQexecPrepared(conn, "prep1", 0, NULL, NULL, NULL, 0);
	if (PQresultStatus(res) != PGRES_TUPLES_OK)
	{
		fprintf(stderr, "PQresultStatus() failed: %s", PQerrorMessage(conn));
		exit_nicely(conn);
	}

	printResultSet(res);
    PQclear(res);
	
    PQfinish(conn);

    return 0;
}

static void
printResultSet(PGresult *res)
{
	int			nFields;
	int			i,
				j;

	/* first, print out the attribute names */
	nFields = PQnfields(res);
	for (i = 0; i < nFields; i++)
		printf("%-15s", PQfname(res, i));
	printf("\n\n");

	/* next, print out the rows */
	for (i = 0; i < PQntuples(res); i++)
	{
		for (j = 0; j < nFields; j++)
			printf("%-15s", PQgetvalue(res, i, j));
		printf("\n");
	}
}