import oracledb
import os
import traceback
import sys


def connect(alias):

    username = os.getenv(alias + "_DB_USER")
    password = os.getenv(alias + "_DB_PASS")
    tnsalias = os.getenv(alias + "_DB_TNS")
    connstr = username + "/" + password + "@" + tnsalias

    oracledb.init_oracle_client()

    try:
        conn = oracledb.connect(connstr)
        return conn
    except oracledb.DatabaseError as db_err:
        tb = traceback.format_exc()
        print(f"DatabaseError connecting to '{alias}': {db_err}\n{tb}", file=sys.stderr)
        sys.exit(1)
    except Exception as exc:
        tb = traceback.format_exc()
        print(f"Unexpected error connecting to '{alias}': {exc}\n{tb}", file=sys.stderr)
        sys.exit(1)


def run_proc(connection, proc: str, param: []):
    curs = connection.cursor()
    curs.callproc(proc, param)


def run_func(connection, proc: str, rettype, param: []):
    curs = connection.cursor()
    ret = curs.callfunc(proc, rettype, param)

    return ret