CREATE FUNCTION _api.user_insert()
RETURNS TRIGGER
LANGUAGE plpgsql VOLATILE
AS $BODY$
DECLARE
	_length INTEGER;
BEGIN
	PERFORM _api.validate_text(
		_text => NEW.username,
		_column => 'username',
		_min => 1,
		_max => 24
	);

	PERFORM TRUE FROM admin.user
		WHERE username = NEW.username;

	IF FOUND THEN
		PERFORM _api.raise_unique('username');
	END IF;

	PERFORM _api.validate_text(
		_text => NEW.password,
		_column => 'password',
		_max => 256
	);

	PERFORM _api.validate_text(
		_text => NEW.first_name,
		_nullable => TRUE,
		_column => 'first_name',
		_max => 256
	);
	NEW.first_name = COALESCE(NEW.first_name, ''::text);

	PERFORM _api.validate_text(
		_text => NEW.last_name,
		_nullable => TRUE,
		_column => 'last_name',
		_max => 256
	);
	NEW.last_name = COALESCE(NEW.last_name, ''::text);

	PERFORM _api.validate_text(
		_text => NEW.middle_name,
		_nullable => TRUE,
		_column => 'middle_name',
		_max => 256
	);
	NEW.middle_name = COALESCE(NEW.middle_name, ''::text);

	PERFORM _api.validate_text(
		_text => NEW.email,
		_column => 'email',
		_max => 256
	);

	PERFORM _api.validate_text(
		_text => NEW.gender,
		_column => 'gender',
		_max => 256
	);

	IF NEW.birth_date IS NULL THEN
		PERFORM _api.raise_null('birth_date');
	END IF;

	PERFORM _api.validate_text(
		_text => NEW.profile_bio,
		_nullable => TRUE,
		_column => 'profile_bio',
		_max => 2048
	);
	NEW.profile_bio = COALESCE(NEW.profile_bio, ''::text);

	INSERT INTO admin.user (
		username,
		password,
		first_name,
		last_name,
		middle_name,
		email,
		gender,
		birth_date,
		profile_avatar,
		profile_banner,
		profile_bio
	) VALUES (
		NEW.username,
		NEW.password,
		NEW.first_name,
		NEW.last_name,
		NEW.middle_name,
		NEW.email,
		NEW.gender,
		NEW.birth_date,
		NEW.profile_avatar,
		NEW.profile_banner,
		NEW.profile_bio
	);

	NEW.password := NULL;

	RETURN NEW;
END
$BODY$;

GRANT EXECUTE ON FUNCTION _api.user_insert()
	TO rest_anon, rest_user;
GRANT INSERT ON TABLE api.user
	TO rest_anon, rest_user;
GRANT INSERT ON TABLE admin.user
	TO rest_anon, rest_user;
GRANT UPDATE ON TABLE sys.user_id_seq
	TO rest_anon, rest_user;

CREATE TRIGGER api_user_insert_trgr
	INSTEAD OF INSERT
			ON api.user
			FOR EACH ROW
				EXECUTE PROCEDURE _api.user_insert();