#coding:utf-8

"""
ID:          issue-8231
ISSUE:       https://github.com/FirebirdSQL/firebird/issues/8231
TITLE:       SubQueryConversion = true --request size limit exceeded / Unsuccessful execution caused by an unavailable resource. unable to allocate memory from operating system
DESCRIPTION:
NOTES:
    [26.08.2024] pzotov
    Two tables must be joined by columns which has different charset or collates.
    Confirmed bug on 5.0.2.1484-3cdfd38 (25.08.2024), got:
        Statement failed, SQLSTATE = HY000
        request size limit exceeded
    Checked on 5.0.2.1485-274af35 -- all ok.

    Thanks to dimitr for the advice on implementing the test.
"""

import pytest
from firebird.qa import *
from firebird.driver import driver_config, connect

init_script = """
    create table t1(fld varchar(10) character set win1252);
    create table t2(fld varchar(10) character set utf8);

    insert into t1(fld) values('Ð');
    insert into t2(fld) values('Ð');
    commit;
"""

db = db_factory(init=init_script)

act = python_act('db')

#-----------------------------------------------------------

def replace_leading(source, char="."):
    stripped = source.lstrip()
    return char * (len(source) - len(stripped)) + stripped

#-----------------------------------------------------------

@pytest.mark.version('>=5.0.2,<6')
def test_1(act: Action, capsys):

    test_sql = """
        select 1 as x
        from t1
        where exists (select 1 from t2 where t1.fld = t2.fld)
    """

    for sq_conv in ('true','false',):
        srv_cfg = driver_config.register_server(name = f'srv_cfg_8231_{sq_conv}', config = '')
        db_cfg_name = f'db_cfg_8231_{sq_conv}'
        db_cfg_object = driver_config.register_database(name = db_cfg_name)
        db_cfg_object.server.value = srv_cfg.name
        db_cfg_object.database.value = str(act.db.db_path)
        db_cfg_object.config.value = f"""
            SubQueryConversion = {sq_conv}
        """

        with connect(db_cfg_name, user = act.db.user, password = act.db.password) as con:
            cur = con.cursor()
            cur.execute("select g.rdb$config_name, g.rdb$config_value from rdb$database r left join rdb$config g on g.rdb$config_name = 'SubQueryConversion'")
            for r in cur:
                print(r[0],r[1])

            ps = cur.prepare(test_sql)

            # Print explained plan with padding eash line by dots in order to see indentations:
            print( '\n'.join([replace_leading(s) for s in ps.detailed_plan.split('\n')]) )

            # Print data:
            for r in cur.execute(ps):
                print(r[0])
            con.rollback()

    act.expected_stdout = f"""
        SubQueryConversion true
        Select Expression
        ....-> Nested Loop Join (semi)
        ........-> Table "T1" Full Scan
        ........-> Filter
        ............-> Table "T2" Full Scan
        1

        SubQueryConversion false
        Sub-query
        ....-> Filter
        ........-> Table "T2" Full Scan
        Select Expression
        ....-> Filter
        ........-> Table "T1" Full Scan
        1
    """
    act.stdout = capsys.readouterr().out
    assert act.clean_stdout == act.clean_expected_stdout