##########################################################################
#
# pgAdmin 4 - PostgreSQL Tools
#
# Copyright (C) 2013 - 2019, The pgAdmin Development Team
# This software is released under the PostgreSQL Licence
#
##########################################################################

from __future__ import print_function

import os
import sys
import traceback

from regression.python_test_utils.test_utils import get_db_connection

file_name = os.path.basename(__file__)


def create_foreign_table(server, db_name, schema_name, fsrv_name,
                         foreign_table_name):
    """
    This function will create foreign table under the existing
    dummy schema.

    :param server: test_server, test_db, fsrv_name, foreign_table_name
    :return: ft_id
    """

    try:
        connection = get_db_connection(db_name,
                                       server['username'],
                                       server['db_password'],
                                       server['host'],
                                       server['port'])
        old_isolation_level = connection.isolation_level
        connection.set_isolation_level(0)
        pg_cursor = connection.cursor()

        pg_cursor.execute(
            "CREATE FOREIGN TABLE " + schema_name + "." + foreign_table_name +
            "(emp_name text NULL) SERVER %s" % fsrv_name)

        connection.set_isolation_level(old_isolation_level)
        connection.commit()

        # Get 'oid' from newly created foreign table
        pg_cursor.execute(
            "SELECT ftrelid FROM pg_foreign_table WHERE ftserver = "
            "(SELECT oid FROM pg_foreign_server WHERE srvname = '%s') "
            "ORDER BY ftrelid ASC limit 1" % fsrv_name)

        oid = pg_cursor.fetchone()
        ft_id = ''
        if oid:
            ft_id = oid[0]
        connection.close()
        return ft_id
    except Exception:
        traceback.print_exc(file=sys.stderr)


def verify_foreign_table(server, db_name, fsrv_name):
    """ This function will verify current foreign table."""

    try:
        connection = get_db_connection(db_name,
                                       server['username'],
                                       server['db_password'],
                                       server['host'],
                                       server['port'])
        pg_cursor = connection.cursor()

        pg_cursor.execute(
            "SELECT ftrelid FROM pg_foreign_table WHERE ftserver = "
            "(SELECT oid FROM pg_foreign_server WHERE srvname = '%s') "
            "ORDER BY ftrelid ASC limit 1" % fsrv_name)
        fts = pg_cursor.fetchone()
        connection.close()
        return fts
    except Exception:
        traceback.print_exc(file=sys.stderr)


def delete_foregin_table(server, db_name, schema_name, ft_name):
    """
    This function delete Foreign table object.
    :param server: server details
    :type server: dict
    :param db_name: database name
    :type db_name: str
    :param ft_name: Foreign table object
    :type ft_name: str
    :param schema_name: schema name
    :type schema_name: str
    :return: None
        """
    connection = get_db_connection(db_name,
                                   server['username'],
                                   server['db_password'],
                                   server['host'],
                                   server['port'],
                                   server['sslmode'])
    pg_cursor = connection.cursor()
    pg_cursor.execute("DROP FOREIGN TABLE %s.%s" % (schema_name, ft_name))
    connection.commit()
    connection.close()