(*
  $Id$
  ISO TC184/SC4/WG12 N2887 - ISO/IS 10303-41 Fundamentals of product description and support - EXPRESS
*) 


SCHEMA qualifications_schema;

REFERENCE FROM support_resource_schema   -- ISO 10303-41
  (bag_to_set,
   identifier,
   label,
   text); 


ENTITY qualification;
  id : identifier;
  name : label;
  description : OPTIONAL text;
END_ENTITY;

ENTITY qualification_relationship;
  id : identifier;
  name : label;
  description : OPTIONAL text;
  relating_qualification : qualification;
  related_qualification : qualification;
END_ENTITY;

ENTITY qualification_type;
  id : identifier;
  name : label;
  description : OPTIONAL text;
END_ENTITY;

ENTITY qualification_type_relationship;
  id : identifier;
  name : label;
  description : OPTIONAL text;
  relating_qualification_type : qualification_type;
  related_qualification_type : qualification_type;
END_ENTITY;

FUNCTION acyclic_qualification_relationship (relation : qualification_relationship; relatives : SET OF qualification; specific_relation : STRING):BOOLEAN;
    LOCAL
      x : SET OF qualification_relationship;
    END_LOCAL;

    IF relation.relating_qualification IN relatives THEN
      RETURN (FALSE);
    END_IF;
    x := QUERY(qual <* bag_to_set(USEDIN(relation.relating_qualification, 'QUALIFICATIONS_SCHEMA.' + 'QUALIFICATION_RELATIONSHIP.' + 'RELATED_QUALIFICATION')) | specific_relation IN TYPEOF(qual));
    REPEAT i := 1 TO HIINDEX(x);
      IF NOT acyclic_qualification_relationship(x[i], relatives + relation.relating_qualification, specific_relation) THEN
        RETURN (FALSE);
      END_IF;
    END_REPEAT;
    RETURN (TRUE);
  END_FUNCTION;

  FUNCTION acyclic_qualification_type_relationship (relation : qualification_type_relationship; relatives : SET OF qualification_type; specific_relation : STRING):BOOLEAN;
    LOCAL
      x : SET OF qualification_type_relationship;
    END_LOCAL;

    IF relation.relating_qualification_type IN relatives THEN
      RETURN (FALSE);
    END_IF;
    x := QUERY(qultyp <* bag_to_set(USEDIN(relation.relating_qualification_type, 'QUALIFICATIONS_SCHEMA.' + 'QUALIFICATION_TYPE_RELATIONSHIP.' + 'RELATED_QUALIFICATION_TYPE')) | specific_relation IN TYPEOF(qultyp));
    REPEAT i := 1 TO HIINDEX(x);
      IF NOT acyclic_qualification_type_relationship(x[i], relatives + relation.relating_qualification_type, specific_relation) THEN
        RETURN (FALSE);
      END_IF;
    END_REPEAT;
    RETURN (TRUE);
  END_FUNCTION;

END_SCHEMA;  -- qualifications_schema

