#coding:utf-8

"""
ID:          issue-5733
ISSUE:       5733
TITLE:       Support GENERATED ALWAYS identity columns and OVERRIDE clause
DESCRIPTION:
JIRA:        CORE-5463
FBTEST:      bugs.core_5463
NOTES:
    [18.07.2023] pzotov
    Adjusted STDERR text after changes related to fixed gh-7638
    ("OVERRIDING USER VALUE should be allowed for GENERATED ALWAYS AS IDENTITY."), see:
        https://github.com/FirebirdSQL/firebird/commit/844631b0ee473fd94dab61558f146a8268c0967b
        https://github.com/FirebirdSQL/firebird/commit/43c5426b48b2647c795143fcaa4a8e20c57fc9c8
    Old text:
        "OVERRIDING SYSTEM VALUE should be used to override the value of an identity column defined as 'GENERATED ALWAYS' in table/view ..."
    New text (after #7638 was fixed):
        "OVERRIDING clause should be used when an identity column defined as 'GENERATED ALWAYS' is present in the INSERT's field list for table table/view ..."
"""

import pytest
from firebird.qa import *

db = db_factory()

test_script = """
    set list on;
    recreate table test_always(
       id_always int generated ALWAYS as identity (start with 11 increment 22) unique
    );

    recreate table test_default(
       id_default int generated BY DEFAULT as identity (start with -11 increment -22) unique
    );


    insert into test_default default values returning id_default; -- expected: -33

    insert into test_always default values returning id_always; -- expected: 33

    -- Comments taken from doc\\sql.extensions\\README.identity_columns.txt
    -- ==================================================================

    -- ........................................
    -- Identity columns are implicitly NOT NULL
    -- ........................................
    -- Statement failed, SQLSTATE = 42000
    -- ::: NB ::: Error text was changed for following statement.
    -- 1. For FB 5.x - since 28-JUN-2023 (old text was up to build 5.0.0.1088, new appeared since 5.0.0.1093)
    -- 2. For FB 4.x - since 08-JUL-2023 (old text was up to build 4.0.3.2958, new appeared since 4.0.3.2963)
    -- OLD TEXT: OVERRIDING SYSTEM VALUE should be used to override the value of an identity column defined as 'GENERATED ALWAYS' in table/view TEST_ALWAYS
    -- NEW TEXT: OVERRIDING clause should be used when an identity column defined as 'GENERATED ALWAYS' is present in the INSERT's field list for table table/view TEST_ALWAYS
    insert into test_always(id_always) values(null);

    -- Statement failed, SQLSTATE = 23000
    -- validation error for column "TEST"."id_default", value "*** null ***"
    insert into test_default(id_default) values(null);


    -- ........................................................................
    -- BY DEFAULT identity columns can be overriden in INSERT statements
    -- just specifying the value in the values list
    -- ........................................................................
    insert into test_default(id_default) values(-7654321) returning id_default;
    -- insert into test_default default values returning id_default; ==> -99 !


    -- ........................................................................
    -- However, for ALWAYS identity columns that is not allowed.
    -- To use the value passed in the INSERT statement for an ALWAYS column, you should pass
    -- OVERRIDING SYSTEM VALUE:
    -- ........................................................................


    -- 1) check that OVERRIDING SYSTEM VALUE clause does not affect on NOT_NULL constraint:
    -- Statement failed, SQLSTATE = 23000
    -- validation error for column "test_always"."ID_ALWAYS", value "*** null ***"
    insert into test_always(id_always) overriding system value values (null) returning id_always;

    -- 2) check ability to override system value by providing our own:
    insert into test_always(id_always) overriding system value values (7654321) returning id_always;

    -- .........................................................................
    -- OVERRIDING also supports a subclause to be used with BY DEFAULT columns,
    -- to ignore the value passed in INSERT and use the defined sequence:
    -- .........................................................................

    -- 1) check that attempt to pass NULL into VALUES list has no effect:
    insert into test_default(id_default) overriding user value values(null) returning id_default; -- expected: -99

    -- 2) check ability to pass allowed value but it also must be overriden by default one:
    insert into test_default(id_default) overriding user value values(-7654322) returning id_default; -- expected: -121
"""

act = isql_act('db', test_script)

expected_stdout = """
    ID_DEFAULT                      -11
    ID_ALWAYS                       11
    ID_DEFAULT                      -7654321
    ID_ALWAYS                       7654321
    ID_DEFAULT                      -33
    ID_DEFAULT                      -55
"""

expected_stderr = """
    Statement failed, SQLSTATE = 42000
    OVERRIDING clause should be used when an identity column defined as 'GENERATED ALWAYS' is present in the INSERT's field list for table table/view TEST_ALWAYS

    Statement failed, SQLSTATE = 23000
    validation error for column "TEST_DEFAULT"."ID_DEFAULT", value "*** null ***"

    Statement failed, SQLSTATE = 23000
    validation error for column "TEST_ALWAYS"."ID_ALWAYS", value "*** null ***"
"""

@pytest.mark.version('>=4.0')
def test_1(act: Action):
    act.expected_stdout = expected_stdout
    act.expected_stderr = expected_stderr
    act.execute()
    assert (act.clean_stderr == act.clean_expected_stderr and
            act.clean_stdout == act.clean_expected_stdout)