#include <stdio.h>
#include <stdlib.h>
#include "/usr/include/postgresql/libpq-fe.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

int main()
{
        char       * conntr = "host='83.168.204.143' dbname='travelfast' user='postgres' password='negergreger'";       /* specify the login settings */
        char        query_string[256];                                                                                  /* Holds constructed SQL query */
        char        modify_string[256];                                                                                 /* Holds constructed SQL query */
        char        modify_first_string[256];                                                                           /* Holds constructed SQL query */
        int         i;                                                                                                  /* Holds the for loop variable */
        int        pid;                                                                                                 /* Holds the pid */
        PGconn     *conn;                                                                                               /* Holds database connection */
        PGresult   *res;                                                                                                /* Holds query result */
        PGresult   *mod;                                                                                                /* Holds query result */
        PGresult   *work;                                                                                               /* Holds query result */

// Create the daemon

        if(fork()) return 0;
        pid = fork();


        if(pid)
        {
                return 0;
        }






/* DB connection */

        conn = PQconnectdb(conntr);
        if (PQstatus(conn) == CONNECTION_BAD)                                                                           /* did the connection fail? */
        {
                fprintf(stderr, "Connection to database failed.\n");
                fprintf(stderr, "%s", PQerrorMessage(conn));
                exit(1);                                                                                                /* Then exit program */
        }


/* loop while the PID is running */

        while(1)
        {





                                                                /* === The SQL Query === */

                        /*  Modify first, "assign these DB-lines to me" */
        sprintf(modify_first_string, "UPDATE foo set server_id = '1' WHERE number IN (SELECT number from foo where working_on = '0' and server_id = '0')");
        mod = PQexec(conn, modify_first_string);

                if (PQcmdTuples(mod) != 0)                                                                              /* if any row were modified, proceed with the program*/
                {
                        PQclear(mod);
                        /*  Select those values */
                        sprintf(query_string, "SELECT * FROM foo WHERE server_id = '1' AND working_on = '0'");          /* Create an SELECT query */
                        res = PQexec(conn, query_string);                                                               /* send the query */

                                if (PQresultStatus(res) != PGRES_TUPLES_OK)                                             /* did the query fail? */
                                {
                                        fprintf(stderr, "SELECT query failed.\n");
                                        PQclear(res);
                                        PQfinish(conn);
                                        exit(1);
                                }

                                if (PQntuples(res) > 0)
                                {
                                        for (i = 0; i < PQntuples(res); i++)                                                            /* loop through all rows returned */
                                        sprintf(modify_string, "UPDATE foo SET working_on = '1' WHERE server_id = '1' AND number = '%s'", PQgetvalue(res, i, 0));
                                        PQclear(res);                                                                                   /* free res for the select-query earlier */
                                        work = PQexec(conn, modify_string);
                                        PQclear(work);                                                                                  /* free result for the modify string */
                                }

                                else
                                {
                                        sleep(1);
                                }
                }

                else
                {
                        printf("sleep 1sek\n");
                        sleep(1);
                }
/* End of the while-loop */
     }


/* Close the connection */
        PQfinish(conn);                                                                                                 /* disconnect from the database */


        /* Exit the program */
        return 0;


}