# -*- coding: utf-8 -*
import psycopg2
import csv
import time

pagination_size = 100000
table_name = "wk_log_2018_08_{}.tb_log_http_2018_08_{}_{} "
sql = "select host, uri, srvAdd, cliAdd, srvprt, rcvTime from " + table_name
sql_cnt = "select count(*) from " + table_name
limit = " offset {} limit " + str(pagination_size)


def save_db_data(rows, save_file):
    with open(save_file + ".log", 'wb') as csv_file:
        csv_w = csv.writer(csv_file, delimiter="|")
        for row in rows:
            row_list = list(row)
            csv_w.writerow(row_list)


def use_pagination():
    try:
        with psycopg2.connect("dbname='admin' user='admin' host='localhost' password='admin'") as conn:
            with conn.cursor() as cur:
                for day in xrange(1, 19):
                    for hour in xrange(0, 24, 2):
                        cur.execute(sql_cnt.format("{0:02d}".format(day), "{0:02d}".format(day),
                                                   "{0:02d}".format(hour)))
                        time.sleep(1)
                        for x in xrange(0, cur.fetchone()[0], pagination_size):
                            cur.execute(sql.format("{0:02d}".format(day), "{0:02d}".format(day),
                                                   "{0:02d}".format(hour)) + limit.format(x))
                            rows = cur.fetchall()
                            if len(rows) > 0:
                                save_db_data(rows, table_name.format("{0:02d}".format(day), "{0:02d}".format(day),
                                                                     "{0:02d}".format(hour)) + "_" + str(x))
                            else:
                                break;
    except Exception as e:
        print("I am unable to connect to the database: " + str(e))


if __name__ == "__main__":
    use_pagination()