/*Зачисление:*/
create or replace function create_debit
(
    _purchase_id int,
    _amount int,
    _started_at timestamp,
    _finished_at timestamp,
    _card_id int,
    _created_at timestamp
)
returns void as
$body$
declare _debit_id int, _saldo INT;
begin
insert into "debits"
(
    "purchase_id",
    "amount",
    "created_at",
    "started_at",
    "finished_at"
)
VALUES
(
    _purchase_id,
    _amount,
    _created_at,
    _started_at,
    _finished_at
)
RETURNING "id" INTO _debit_id;

IF NOW() >= _started_at
    SELECT INTO _saldo "saldo" FROM "accounts" WHERE "card_id" = _card_id ORDER BY "created_at" DESC LIMIT 1;

    IF _saldo IS NULL
        THEN _saldo = 0;
    END IF;

    INSERT INTO "accounts"
    (
        "card_id",
        "debit_amount",
        "debit_id",
        "created_at",
        "saldo"
    )
    VALUES
    (
        _card_id,
        _amount,
        _debit_id,
        NOW(),
        _saldo + _amount
    );
END IF;
end
$body$
LANGUAGE 'plpgsql'