--
-- Additional scalar types with no dedicated Ruby representation: uuid, inet,
-- enums, and domains.  All travel as strings; constraints and input
-- validation stay on the PostgreSQL side.
--
-- uuid round-trips as its canonical lower-case text form.
CREATE FUNCTION u_echo(uuid) RETURNS uuid LANGUAGE plruby AS $$
    args[0]
$$;
SELECT u_echo('A0EEBC99-9C0B-4EF8-BB6D-6BB9BD380A11');
                u_echo                
--------------------------------------
 a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11
(1 row)

CREATE FUNCTION u_class(uuid) RETURNS text LANGUAGE plruby AS $$
    args[0].class.name
$$;
SELECT u_class('a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11');
 u_class 
---------
 String
(1 row)

-- inet/cidr as strings; the network math stays in SQL.
CREATE FUNCTION net_echo(inet) RETURNS inet LANGUAGE plruby AS $$
    args[0]
$$;
SELECT net_echo('192.168.100.128/25');
      net_echo      
--------------------
 192.168.100.128/25
(1 row)

SELECT net_echo('::1');
 net_echo 
----------
 ::1
(1 row)

-- An enum arrives as its label and may be returned as one.
CREATE TYPE mt_mood AS ENUM ('sad', 'ok', 'happy');
CREATE FUNCTION mood_up(mt_mood) RETURNS mt_mood LANGUAGE plruby AS $$
    order_ = ['sad', 'ok', 'happy']
    order_[[order_.index(args[0]) + 1, order_.length - 1].min]
$$;
SELECT mood_up('sad'), mood_up('ok'), mood_up('happy');
 mood_up | mood_up | mood_up 
---------+---------+---------
 ok      | happy   | happy
(1 row)

-- Returning a label that is not part of the enum is rejected.
CREATE FUNCTION mood_bad() RETURNS mt_mood LANGUAGE plruby AS $$
    'ecstatic'
$$;
SELECT mood_bad();
ERROR:  invalid input value for enum mt_mood: "ecstatic"
CONTEXT:  PL/Ruby function "mood_bad"
-- Domains: values returned into a domain are checked by its constraint.
CREATE DOMAIN mt_posint AS int CHECK (VALUE > 0);
CREATE FUNCTION pos_ok(int) RETURNS mt_posint LANGUAGE plruby AS $$
    args[0]
$$;
SELECT pos_ok(5);
 pos_ok 
--------
      5
(1 row)

SELECT pos_ok(-5);
ERROR:  value for domain mt_posint violates check constraint "mt_posint_check"
CONTEXT:  PL/Ruby function "pos_ok"
-- A domain-typed argument arrives as its base type's Ruby value (the
-- domain's constraints were already enforced when the value was created).
CREATE FUNCTION pos_class(mt_posint) RETURNS text LANGUAGE plruby AS $$
    "#{args[0].class.name}=#{args[0]}"
$$;
SELECT pos_class(41);
 pos_class  
------------
 Integer=41
(1 row)

-- ... including a domain over an array type.
CREATE DOMAIN mt_intlist AS int[] CHECK (array_length(VALUE, 1) <= 3);
CREATE FUNCTION list_class(mt_intlist) RETURNS text LANGUAGE plruby AS $$
    "#{args[0].class.name}=#{args[0].inspect}"
$$;
SELECT list_class(ARRAY[1, 2]);
  list_class  
--------------
 Array=[1, 2]
(1 row)

DROP FUNCTION list_class(mt_intlist);
DROP DOMAIN mt_intlist;
DROP FUNCTION pos_class(mt_posint);
DROP FUNCTION pos_ok(int);
DROP DOMAIN mt_posint;
DROP FUNCTION mood_up(mt_mood);
DROP FUNCTION mood_bad();
DROP TYPE mt_mood;