--
-- acs-kernel/sql/acs-objects-create.sql
--
-- A base object type that provides auditing columns, permissioning,
-- attributes, and relationships to any subtypes.
--
-- @author Michael Yoon (michael@arsdigita.com)
-- @author Rafael Schloming (rhs@mit.edu)
-- @author Jon Salz (jsalz@mit.edu)
--
-- @creation-date 2000-05-18
--
-- @cvs-id acs-objects-create.sql,v 1.15.2.2 2001/01/12 22:54:24 oumi Exp
--

-----------------------------
-- PREDEFINED OBJECT TYPES --
-----------------------------

create function inline_0 ()
returns integer as '
declare
 attr_id acs_attributes.attribute_id%TYPE;
begin
 --
 -- The ultimate supertype: object
 --
 PERFORM acs_object_type__create_type (
   ''acs_object'',
   ''Object'',
   ''Objects'',
   null,
   ''acs_objects'',
   ''object_id'',
   ''acs_object'',
   ''f'',
   null,
   ''acs_object.default_name''
   );

 attr_id := acs_attribute__create_attribute (
   ''acs_object'',
   ''object_type'',
   ''string'',
   ''Object Type'',
   ''Object Types'',
   null,
   null,
   null,   
   1,
   1,
   null,
   ''type_specific'',
   ''f''
   );

 attr_id := acs_attribute__create_attribute (
   ''acs_object'',
   ''creation_date'',
   ''date'',
   ''Created Date'',
   null,
   null,
   null,
   null,
   1,
   1,
   null,
   ''type_specific'',
   ''f''
   );

 attr_id := acs_attribute__create_attribute (
   ''acs_object'',
   ''creation_ip'',
   ''string'',
   ''Creation IP Address'',
   null,
   null,
   null,
   null,
   1,
   1,
   null,
   ''type_specific'',
   ''f''
   );

 attr_id := acs_attribute__create_attribute (
   ''acs_object'',
   ''last_modified'',
   ''date'',
   ''Last Modified On'',
   null,
   null,
   null,
   null,
   1,
   1,
   null,
   ''type_specific'',
   ''f''
   );

 attr_id := acs_attribute__create_attribute (
   ''acs_object'',
   ''modifying_ip'',
   ''string'',
   ''Modifying IP Address'',
   null,
   null,
   null,
   null,
   1,
   1,
   null,
   ''type_specific'',
   ''f''
   );

 attr_id := acs_attribute__create_attribute (
	''acs_object'',
	''creation_user'',
	''integer'',
	''Creation user'',
	''Creation users'',
	null,
	null,
	null,
	0,
	1,
	null,
	''type_specific'',
	''f''
	);

 attr_id := acs_attribute__create_attribute (
	''acs_object'',
	''context_id'',
	''integer'',
	''Context ID'',
	''Context IDs'',
	null,
	null,
	null,
	0,
	1,
	null,
	''type_specific'',
	''f''
	);

  return 0;
end;' language 'plpgsql';

select inline_0 ();

drop function inline_0 ();


-- show errors

-- ******************************************************************
-- * OPERATIONAL LEVEL
-- ******************************************************************

-------------
-- OBJECTS --
-------------

create sequence t_acs_object_id_seq;
create view acs_object_id_seq as
select nextval('t_acs_object_id_seq') as nextval;

create table acs_objects (
	object_id		integer not null
				constraint acs_objects_pk primary key,
	object_type		varchar(100) not null
				constraint acs_objects_object_type_fk
				references acs_object_types (object_type),
        context_id		integer constraint acs_objects_context_id_fk
				references acs_objects(object_id),
	security_inherit_p	boolean default 't' not null,
	creation_user		integer,
	creation_date		timestamp default now() not null,
	creation_ip		varchar(50) default '' not null,
	last_modified		timestamp default now() not null,
	modifying_user		integer,
	modifying_ip		varchar(50) default '' not null,
        tree_sortkey            varchar(4000),
        constraint acs_objects_context_object_un
	unique (context_id, object_id)
);

create index acs_objects_context_object_idx on
       acs_objects (context_id, object_id);

create index acs_objs_tree_skey_idx on acs_objects (tree_sortkey);

-- alter table acs_objects modify constraint acs_objects_context_object_un enable;

create index acs_objects_creation_user_idx on acs_objects (creation_user);
create index acs_objects_modify_user_idx on acs_objects (modifying_user);

create index acs_objects_object_type_idx on acs_objects (object_type);

create function acs_objects_mod_ip_insert_tr () returns opaque as '
begin
  new.modifying_ip := new.creation_ip;

  return new;

end;' language 'plpgsql';

create trigger acs_objects_mod_ip_insert_tr before insert on acs_objects
for each row execute procedure acs_objects_mod_ip_insert_tr ();

-- show errors

create function acs_objects_last_mod_update_tr () returns opaque as '
begin
  new.last_modified := now();

  return new;

end;' language 'plpgsql';

create trigger acs_objects_last_mod_update_tr before update on acs_objects
for each row execute procedure acs_objects_last_mod_update_tr ();

create function acs_objects_insert_tr () returns opaque as '
declare
        v_parent_sk     varchar;
        max_key         varchar;
begin
        if new.context_id is null then 
            select max(tree_sortkey) into max_key 
              from acs_objects 
             where context_id is null;

            v_parent_sk := '''';
        else 
            select max(tree_sortkey) into max_key 
              from acs_objects 
             where context_id = new.context_id;

            select coalesce(max(tree_sortkey),'''') into v_parent_sk 
              from acs_objects 
             where object_id = new.context_id;
        end if;


        new.tree_sortkey := v_parent_sk || ''/'' || tree_next_key(max_key);

        return new;

end;' language 'plpgsql';

create trigger acs_objects_insert_tr before insert 
on acs_objects for each row 
execute procedure acs_objects_insert_tr ();

create function acs_objects_update_tr () returns opaque as '
declare
        v_parent_sk     varchar;
        max_key         varchar;
        ctx_id          integer;
        v_rec           record;
        clr_keys_p      boolean default ''t'';
begin
        if new.object_id = old.object_id and 
           ((new.context_id = old.context_id) or
            (new.context_id is null and old.context_id is null)) then

           return new;

        end if;

        for v_rec in select object_id
                       from acs_objects 
                      where tree_sortkey like new.tree_sortkey || ''%''
                   order by tree_sortkey
        LOOP
            if clr_keys_p then
               update acs_objects set tree_sortkey = null
               where tree_sortkey like new.tree_sortkey || ''%'';
               clr_keys_p := ''f'';
            end if;
            
            select context_id into ctx_id
              from acs_objects 
             where object_id = v_rec.object_id;

            if ctx_id is null then 
                select max(tree_sortkey) into max_key
                  from acs_objects 
                 where context_id is null;

                v_parent_sk := '''';
            else 
                select max(tree_sortkey) into max_key
                  from acs_objects 
                 where context_id = ctx_id;

                select coalesce(max(tree_sortkey),'''') into v_parent_sk 
                  from acs_objects 
                 where object_id = ctx_id;
            end if;

            update acs_objects 
               set tree_sortkey = v_parent_sk || ''/'' || tree_next_key(max_key)
             where object_id = v_rec.object_id;

        end LOOP;

        return new;

end;' language 'plpgsql';

create trigger acs_objects_update_tr after update 
on acs_objects
for each row 
execute procedure acs_objects_update_tr ();

-- show errors

comment on table acs_objects is '
';

comment on column acs_objects.context_id is '
 The context_id column points to an object that provides a context for
 this object. Often this will reflect an observed hierarchy in a site,
 for example a bboard message would probably list a bboard topic as
 it''s context, and a bboard topic might list a sub-site as it''s
 context. Whenever we ask a question of the form "can user X perform
 action Y on object Z", the acs security model will defer to an
 object''s context if there is no information about user X''s
 permission to perform action Y on object Z.
';

comment on column acs_objects.creation_user is '
 Who created the object; may be null since objects can be created by
 automated processes
';

comment on column acs_objects.modifying_user is '
 Who last modified the object
';

-----------------------
-- CONTEXT HIERARCHY --
-----------------------

create table acs_object_context_index (
	object_id	integer not null
                        constraint acs_obj_context_idx_obj_id_fk
			references acs_objects(object_id),
	ancestor_id	integer not null
                        constraint acs_obj_context_idx_anc_id_fk
			references acs_objects(object_id),
	n_generations	integer not null
			constraint acs_obj_context_idx_n_gen_ck
			check (n_generations >= 0),
        constraint acs_object_context_index_pk
	primary key (object_id, ancestor_id)
);

create index acs_obj_ctx_idx_ancestor_idx on acs_object_context_index (ancestor_id);

create view acs_object_paths
as select object_id, ancestor_id, n_generations
   from acs_object_context_index;

create view acs_object_contexts
as select object_id, ancestor_id, n_generations
   from acs_object_context_index
   where object_id != ancestor_id;

create function acs_objects_context_id_in_tr () returns opaque as '
begin
  insert into acs_object_context_index
   (object_id, ancestor_id, n_generations)
  values
   (new.object_id, new.object_id, 0);

  if new.context_id is not null and new.security_inherit_p = ''t'' then
    insert into acs_object_context_index
     (object_id, ancestor_id, n_generations)
    select
     new.object_id as object_id, ancestor_id,
     n_generations + 1 as n_generations
    from acs_object_context_index
    where object_id = new.context_id;
  else if new.object_id != 0 then
    -- 0 is the id of the security context root object
    insert into acs_object_context_index
     (object_id, ancestor_id, n_generations)
    values
     (new.object_id, 0, 1);
  end if; end if;

  return new;

end;' language 'plpgsql';

create trigger acs_objects_context_id_in_tr after insert on acs_objects
for each row execute procedure acs_objects_context_id_in_tr ();

-- show errors

create function acs_objects_context_id_up_tr () returns opaque as '
declare
        pair    record;
begin
  if new.object_id = old.object_id and
     new.context_id = old.context_id and
     new.security_inherit_p = old.security_inherit_p then
    return new;
  end if;

  -- Remove my old ancestors from my descendants.
  delete from acs_object_context_index
  where object_id in (select object_id
                      from acs_object_contexts
                      where ancestor_id = old.object_id)
  and ancestor_id in (select ancestor_id
		      from acs_object_contexts
		      where object_id = old.object_id);

  -- Kill all my old ancestors.
  delete from acs_object_context_index
  where object_id = old.object_id;

  insert into acs_object_context_index
   (object_id, ancestor_id, n_generations)
  values
   (new.object_id, new.object_id, 0);

  if new.context_id is not null and new.security_inherit_p = ''t'' then
     -- Now insert my new ancestors for my descendants.
    for pair in select *
		 from acs_object_context_index
		 where ancestor_id = new.object_id 
    LOOP
      insert into acs_object_context_index
       (object_id, ancestor_id, n_generations)
      select
       pair.object_id, ancestor_id,
       n_generations + pair.n_generations + 1 as n_generations
      from acs_object_context_index
      where object_id = new.context_id;
    end loop;
  else if new.object_id != 0 then
    -- We need to make sure that new.OBJECT_ID and all of its
    -- children have 0 as an ancestor.
    for pair in  select *
		 from acs_object_context_index
		 where ancestor_id = new.object_id 
    LOOP
      insert into acs_object_context_index
       (object_id, ancestor_id, n_generations)
      values
       (pair.object_id, 0, pair.n_generations + 1);
    end loop;
  end if; end if;

  return new;

end;' language 'plpgsql';

create trigger acs_objects_context_id_up_tr after update on acs_objects
for each row execute procedure acs_objects_context_id_up_tr ();

-- show errors

create function acs_objects_context_id_del_tr () returns opaque as '
begin
  delete from acs_object_context_index
  where object_id = old.object_id;

  return old;

end;' language 'plpgsql';

create trigger acs_objects_context_id_del_tr before delete on acs_objects
for each row execute procedure acs_objects_context_id_del_tr ();

-- show errors

----------------------
-- ATTRIBUTE VALUES --
----------------------

create sequence t_acs_attribute_value_id_seq;
create view acs_attribute_value_id_seq as
select nextval('t_acs_attribute_value_id_seq') as nextval;

create table acs_attribute_values (
	object_id	integer not null
			constraint acs_attr_values_obj_id_fk
			references acs_objects (object_id) on delete cascade,
	attribute_id	integer not null
			constraint acs_attr_values_attr_id_fk
			references acs_attributes (attribute_id),
	attr_value	text default '' not null,
	constraint acs_attribute_values_pk primary key
	(object_id, attribute_id)
);

create index acs_attr_values_attr_id_idx on acs_attribute_values (attribute_id);

comment on table acs_attribute_values is '
  Instead of coercing everything into a big string, we could use
  a "union", i.e, a string column, a number column, a date column,
  and a discriminator.
';

create table acs_static_attr_values (
	object_type	varchar(100) not null
			constraint acs_static_a_v_obj_id_fk
			references acs_object_types (object_type) on delete cascade,
	attribute_id	integer not null
			constraint acs_static_a_v_attr_id_fk
			references acs_attributes (attribute_id),
	attr_value	text default '' not null,
	constraint acs_static_a_v_pk primary key
	(object_type, attribute_id)
);

create index acs_stat_attrs_attr_id_idx on acs_static_attr_values (attribute_id);

comment on table acs_static_attr_values is '
  Stores static values for the object attributes. One row per object
  type.
';

------------------------
-- ACS_OBJECT PACKAGE --
------------------------

-- create or replace package acs_object
-- as
-- 
--  function new (
--   object_id	in acs_objects.object_id%TYPE default null,
--   object_type	in acs_objects.object_type%TYPE
-- 			   default 'acs_object',
--   creation_date	in acs_objects.creation_date%TYPE
-- 			   default sysdate,
--   creation_user	in acs_objects.creation_user%TYPE
-- 			   default null,
--   creation_ip	in acs_objects.creation_ip%TYPE default null,
--   context_id    in acs_objects.context_id%TYPE default null
--  ) return acs_objects.object_id%TYPE;
-- 
--  procedure delete (
--   object_id	in acs_objects.object_id%TYPE
--  );
-- 
--  function name (
--   object_id	in acs_objects.object_id%TYPE
--  ) return varchar2;
-- 
--  -- The acs_object_types.name_method for "acs_object"
--  --
--  function default_name (
--   object_id	in acs_objects.object_id%TYPE
--  ) return varchar2;
-- 
--  -- Determine where the attribute is stored and what sql needs to be
--  -- in the where clause to retreive it
--  -- Used in get_attribute and set_attribute
--  procedure get_attribute_storage ( 
--    object_id_in      in  acs_objects.object_id%TYPE,
--    attribute_name_in in  acs_attributes.attribute_name%TYPE,
--    v_column          out varchar2,
--    v_table_name      out varchar2,
--    v_key_sql         out varchar2
--  );
-- 
--  -- Get/set the value of an object attribute, as long as
--  -- the type can be cast to varchar2
--  function get_attribute (
--    object_id_in      in  acs_objects.object_id%TYPE,
--    attribute_name_in in  acs_attributes.attribute_name%TYPE
--  ) return varchar2;
-- 
--  procedure set_attribute (
--    object_id_in      in  acs_objects.object_id%TYPE,
--    attribute_name_in in  acs_attributes.attribute_name%TYPE,
--    value_in          in  varchar2
--  );
-- 
--  function check_representation (
--    object_id		in acs_objects.object_id%TYPE
--  ) return char;
-- 
-- end acs_object;

-- show errors

-- create or replace package body acs_object
-- procedure initialize_attributes
create function acs_object__initialize_attributes (integer)
returns integer as '
declare
  initialize_attributes__object_id              alias for $1;  
  v_object_type                                 acs_objects.object_type%TYPE;
begin
   -- XXX This should be fixed to initialize supertypes properly.

   -- Initialize dynamic attributes
   insert into acs_attribute_values
    (object_id, attribute_id, attr_value)
   select
    initialize_attributes__object_id, a.attribute_id, a.default_value
   from acs_attributes a, acs_objects o
   where a.object_type = o.object_type
   and o.object_id = initialize_attributes__object_id
   and a.storage = ''generic''
   and a.static_p = ''f'';

   -- Retreive type for static attributes
   select object_type into v_object_type from acs_objects
     where object_id = initialize_attributes__object_id;

   -- Initialize static attributes
   -- begin
     insert into acs_static_attr_values
      (object_type, attribute_id, attr_value)
     select
      v_object_type, a.attribute_id, a.default_value
     from acs_attributes a, acs_objects o
     where a.object_type = o.object_type
       and o.object_id = initialize_attributes__object_id
       and a.storage = ''generic''
       and a.static_p = ''t''
       and not exists (select 1 from acs_static_attr_values
                       where object_type = a.object_type);
   -- exception when no_data_found then null;

   return 0; 
end;' language 'plpgsql';


-- function new
create function acs_object__new (integer,varchar,timestamp,integer,varchar,integer)
returns integer as '
declare
  new__object_id              alias for $1;  -- default null
  new__object_type            alias for $2;  -- default ''acs_object''
  new__creation_date          alias for $3;  -- default now()
  new__creation_user          alias for $4;  -- default null
  new__creation_ip            alias for $5;  -- default null
  new__context_id             alias for $6;  -- default null
  v_object_id                 acs_objects.object_id%TYPE;
begin
  if new__object_id is null then
   select acs_object_id_seq.nextval
   into v_object_id from dual;
  else
    v_object_id := new__object_id;
  end if;

  insert into acs_objects
   (object_id, object_type, context_id,
    creation_date, creation_user, creation_ip)
  values
   (v_object_id, new__object_type, new__context_id,
    new__creation_date, new__creation_user, coalesce(new__creation_ip,''''));

  PERFORM acs_object__initialize_attributes(v_object_id);

  return v_object_id;
  
end;' language 'plpgsql';

create function acs_object__new (integer,varchar) returns integer as '
declare
        object_id       alias for $1; -- default null
        object_type     alias for $2; -- default ''acs_object''
begin
        return acs_object__new(object_id,object_type,now(),null,null,null);
end;' language 'plpgsql';


-- procedure delete
create function acs_object__delete (integer)
returns integer as '
declare
  delete__object_id              alias for $1;  
  obj_type                       record;
begin
  
  -- Delete dynamic/generic attributes
  delete from acs_attribute_values where object_id = delete__object_id;

  -- select table_name, id_column
  --  from acs_object_types
  --  start with object_type = (select object_type
  --                              from acs_objects o
  --                             where o.object_id = delete__object_id)
  --  connect by object_type = prior supertype

  for obj_type
  in select o2.table_name, o2.id_column
        from acs_object_types o1, acs_object_types o2
       where o1.object_type = (select object_type
                                 from acs_objects o
                                where o.object_id = delete__object_id)
         and o2.tree_sortkey <= o1.tree_sortkey
         and o1.tree_sortkey like (o2.tree_sortkey || ''%'') 
    order by o2.tree_sortkey desc
  loop
    -- Delete from the table.
    execute ''delete from '' || quote_ident(obj_type.table_name) ||
        '' where '' || quote_ident(obj_type.id_column) || '' =  '' || delete__object_id;
  end loop;

  return 0; 
end;' language 'plpgsql';


-- function name
create function acs_object__name (integer)
returns varchar as '
declare
  name__object_id        alias for $1;  
  object_name            varchar;  
  v_object_id            integer;
  obj_type               record;  
  obj                    record;      
begin
  -- Find the name function for this object, which is stored in the
  -- name_method column of acs_object_types. Starting with this
  -- object''s actual type, traverse the type hierarchy upwards until
  -- a non-null name_method value is found.
  --
  -- select name_method
  --  from acs_object_types
  -- start with object_type = (select object_type
  --                             from acs_objects o
  --                            where o.object_id = name__object_id)
  -- connect by object_type = prior supertype

  for obj_type
  in select o2.name_method
        from acs_object_types o1, acs_object_types o2
       where o1.object_type = (select object_type
                                 from acs_objects o
                                where o.object_id = name__object_id)
         and o2.tree_sortkey <= o1.tree_sortkey
         and o1.tree_sortkey like (o2.tree_sortkey || ''%'') 
    order by o2.tree_sortkey desc
  loop
   if obj_type.name_method != '''' then

    -- Execute the first name_method we find (since we''re traversing
    -- up the type hierarchy from the object''s exact type) using
    -- Native Dynamic SQL, to ascertain the name of this object.
    --
    --execute ''select '' || object_type.name_method || ''(:1) from dual''

    for obj in execute ''select '' || obj_type.name_method || ''('' || name__object_id || '')::varchar as object_name'' loop
        object_name := obj.object_name;
        exit;
    end loop;

    exit;
   end if;
  end loop;

  return object_name;
  
end;' language 'plpgsql';


-- function default_name
create function acs_object__default_name (integer)
returns varchar as '
declare
  default_name__object_id   alias for $1;  
  object_type_pretty_name   acs_object_types.pretty_name%TYPE;
begin
  select ot.pretty_name
  into object_type_pretty_name
  from acs_objects o, acs_object_types ot
  where o.object_id = default_name__object_id
  and o.object_type = ot.object_type;

  return object_type_pretty_name || '' '' || default_name__object_id;
  
end;' language 'plpgsql';


-- procedure get_attribute_storage
create function acs_object__get_attribute_storage (integer,varchar)
returns text as '
declare
  object_id_in           alias for $1;  
  attribute_name_in      alias for $2;  

--  these three are the out variables
  v_column               varchar;  
  v_table_name           varchar;  
  v_key_sql              text;
  
  v_object_type          acs_attributes.object_type%TYPE;
  v_static               acs_attributes.static_p%TYPE;
  v_attr_id              acs_attributes.attribute_id%TYPE;
  v_storage              acs_attributes.storage%TYPE;
  v_attr_name            acs_attributes.attribute_name%TYPE;
  v_id_column            varchar(200);   
  v_sql                  text;  
  v_return               text;  
  v_rec                  record;
begin
   --   select 
   --     object_type, id_column
   --   from
   --     acs_object_types
   --   connect by
   --     object_type = prior supertype
   --   start with
   --     object_type = (select object_type from acs_objects 
   --                    where object_id = object_id_in)

   -- Determine the attribute parameters
   select
     a.attribute_id, a.static_p, a.storage, a.table_name, a.attribute_name,
     a.object_type, a.column_name, t.id_column 
   into 
     v_attr_id, v_static, v_storage, v_table_name, v_attr_name, 
     v_object_type, v_column, v_id_column
   from 
     acs_attributes a,
     (select o2.object_type, o2.id_column
       from acs_object_types o1, acs_object_types o2
      where o1.object_type = (select object_type
                                from acs_objects o
                               where o.object_id = object_id_in)
        and o2.tree_sortkey <= o1.tree_sortkey
        and o1.tree_sortkey like (o2.tree_sortkey || ''%'') 
     ) t
   where   
     a.attribute_name = attribute_name_in
   and
     a.object_type = t.object_type;

   if NOT FOUND then 
      raise EXCEPTION ''-20000: No such attribute %::% in acs_object.get_attribute_storage.'', v_object_type, attribute_name_in;
   end if;

   -- This should really be done in a trigger on acs_attributes,
   -- instead of generating it each time in this function

   -- If there is no specific table name for this attribute,
   -- figure it out based on the object type
   if v_table_name is null or v_table_name = '''' then

     -- Determine the appropriate table name
     if v_storage = ''generic'' then
       -- Generic attribute: table name/column are hardcoded

       v_column := ''attr_value'';

       if v_static = ''f'' then
         v_table_name := ''acs_attribute_values'';
         v_key_sql := ''(object_id = '' || object_id_in || '' and '' ||
                      ''attribute_id = '' || v_attr_id || '')'';
       else
         v_table_name := ''acs_static_attr_values'';
         v_key_sql := ''(object_type = '''''' || v_object_type || '''''' and '' ||
                      ''attribute_id = '' || v_attr_id || '')'';
       end if;

     else
       -- Specific attribute: table name/column need to be retreived
 
       if v_static = ''f'' then
         select 
           table_name, id_column 
         into 
           v_table_name, v_id_column
         from 
           acs_object_types 
         where 
           object_type = v_object_type;
         if NOT FOUND then 
            raise EXCEPTION ''-20000: No data found for attribute %::% in acs_object.get_attribute_storage'', v_object_type, attribute_name_in;
         end if;
       else
         raise EXCEPTION ''-20000: No table name specified for storage specific static attribute %::% in acs_object.get_attribute_storage.'',v_object_type, attribute_name_in;
       end if;
  
     end if;
   else 
     -- There is a custom table name for this attribute.
     -- Get the id column out of the acs_object_tables
     -- Raise an error if not found
     select id_column into v_id_column from acs_object_type_tables
       where object_type = v_object_type 
       and table_name = v_table_name;
       if NOT FOUND then 
          raise EXCEPTION ''-20000: No data found for attribute %::% in acs_object.get_attribute_storage'', v_object_type, attribute_name_in;
       end if;
   end if;

   if v_column is null or v_column = '''' then

     if v_storage = ''generic'' then
       v_column := ''attr_value'';
     else
       v_column := v_attr_name;
     end if;

   end if;

   if v_key_sql is null or v_key_sql = '''' then
     if v_static = ''f'' then   
       v_key_sql := v_id_column || '' = '' || object_id_in ; 
     else
       v_key_sql := v_id_column || '' = '''''' || v_object_type || '''''''';
     end if;
   end if;

   return v_column || '','' || v_table_name || '','' || v_key_sql; 

end;' language 'plpgsql';


create function acs_object__get_attr_storage_column(text) 
returns text as '
declare
        v_vals  alias for $1;
        v_idx   integer;
begin
        v_idx := strpos(v_vals,'','');
        if v_idx = 0 then 
           raise exception ''invalid storage format: acs_object.get_attr_storage_column'';
        end if;

        return substr(v_vals,1,v_idx - 1);

end;' language 'plpgsql';

create function acs_object__get_attr_storage_table(text) 
returns text as '
declare
        v_vals  alias for $1;
        v_idx   integer;
        v_tmp   varchar;
begin
        v_idx := strpos(v_vals,'','');
        if v_idx = 0 then 
           raise exception ''invalid storage format: acs_object.get_attr_storage_table'';
        end if;
        v_tmp := substr(v_vals,v_idx + 1);
        v_idx := strpos(v_tmp,'','');
        if v_idx = 0 then 
           raise exception ''invalid storage format: acs_object.get_attr_storage_table'';
        end if;

        return substr(v_tmp,1,v_idx - 1);

end;' language 'plpgsql';

create function acs_object__get_attr_storage_sql(text) 
returns text as '
declare
        v_vals  alias for $1;
        v_idx   integer;
        v_tmp   varchar;
begin
        v_idx := strpos(v_vals, '','');
        if v_idx = 0 then 
           raise exception ''invalid storage format: acs_object.get_attr_storage_sql'';
        end if;
        v_tmp := substr(v_vals, v_idx + 1);
        v_idx := strpos(v_tmp, '','');
        if v_idx = 0 then 
           raise exception ''invalid storage format: acs_object.get_attr_storage_sql'';
        end if;

        return substr(v_tmp, v_idx + 1);

end;' language 'plpgsql';

-- function get_attribute
create function acs_object__get_attribute (integer,varchar)
returns varchar as '
declare
  object_id_in           alias for $1;  
  attribute_name_in      alias for $2;  
  v_table_name           varchar(200);  
  v_column               varchar(200);  
  v_key_sql              text; 
  v_return               text; 
  v_storage              text;
  v_rec                  record;
begin

   v_storage := acs_object__get_attribute_storage(object_id_in, attribute_name_in);

   v_column     := acs_object__get_attr_storage_column(v_storage);
   v_table_name := acs_object__get_attr_storage_table(v_storage);
   v_key_sql    := acs_object__get_attr_storage_sql(v_storage);

   for v_rec in execute ''select '' || quote_ident(v_column) || '' as return from '' || quote_ident(v_table_name) || '' where '' || v_key_sql
      LOOP
        v_return := v_rec.return;
        exit;
   end loop;
   if not FOUND then 
       return null;
   end if;

   return v_return;

end;' language 'plpgsql';


-- procedure set_attribute
create function acs_object__set_attribute (integer,varchar,varchar)
returns integer as '
declare
  object_id_in           alias for $1;  
  attribute_name_in      alias for $2;  
  value_in               alias for $3;  
  v_table_name           varchar;  
  v_column               varchar;  
  v_key_sql              text; 
  v_return               text; 
  v_storage              text;
begin

   v_storage := acs_object__get_attribute_storage(object_id_in, attribute_name_in);

   v_column     := acs_object__get_attr_storage_column(v_storage);
   v_table_name := acs_object__get_attr_storage_table(v_storage);
   v_key_sql    := acs_object__get_attr_storage_sql(v_storage);

   execute ''update '' || v_table_name || '' set '' || quote_ident(v_column) || '' = '' || quote_literal(value_in) || '' where '' || v_key_sql;

   return 0; 
end;' language 'plpgsql';


-- function check_context_index
create function acs_object__check_context_index (integer,integer,integer)
returns boolean as '
declare
  check_context_index__object_id              alias for $1;  
  check_context_index__ancestor_id            alias for $2;  
  check_context_index__n_generations          alias for $3;  
  n_rows                                      integer;       
  n_gens                                      integer;       
begin
   -- Verify that this row exists in the index.
   select case when count(*) = 0 then 0 else 1 end into n_rows
   from acs_object_context_index
   where object_id = check_context_index__object_id
   and ancestor_id = check_context_index__ancestor_id;

   if n_rows = 1 then
     -- Verify that the count is correct.
     select n_generations into n_gens
     from acs_object_context_index
     where object_id = check_context_index__object_id
     and ancestor_id = check_context_index__ancestor_id;

     if n_gens != check_context_index__n_generations then
       PERFORM acs_log__error(''acs_object.check_representation'', 
                              ''Ancestor '' ||
                     check_context_index__ancestor_id || '' of object '' || 
                     check_context_index__object_id ||
		     '' reports being generation '' || n_gens ||
		     '' when it is actually generation '' || 
                     check_context_index__n_generations ||
		     ''.'');
       return ''f'';
     else
       return ''t'';
     end if;
   else
     PERFORM acs_log__error(''acs_object.check_representation'', 
                            ''Ancestor '' ||
                            check_context_index__ancestor_id || 
                            '' of object '' || check_context_index__object_id 
                            || '' is missing an entry in acs_object_context_index.'');
     return ''f'';
   end if;
  
end;' language 'plpgsql';


-- function check_object_ancestors
create function acs_object__check_object_ancestors (integer,integer,integer)
returns boolean as '
declare
  check_object_ancestors__object_id              alias for $1;  
  check_object_ancestors__ancestor_id            alias for $2;  
  check_object_ancestors__n_generations          alias for $3;  
  check_object_ancestors__context_id             acs_objects.context_id%TYPE;
  check_object_ancestors__security_inherit_p     acs_objects.security_inherit_p%TYPE;
  n_rows                                         integer;       
  n_gens                                         integer;       
  result                                         boolean;       
begin
   -- OBJECT_ID is the object we are verifying
   -- ANCESTOR_ID is the current ancestor we are tracking
   -- N_GENERATIONS is how far ancestor_id is from object_id

   -- Note that this function is only supposed to verify that the
   -- index contains each ancestor for OBJECT_ID. It doesn''''t
   -- guarantee that there aren''''t extraneous rows or that
   -- OBJECT_ID''''s children are contained in the index. That is
   -- verified by seperate functions.

   result := ''t'';

   -- Grab the context and security_inherit_p flag of the current
   -- ancestor''''s parent.
   select context_id, security_inherit_p 
   into check_object_ancestors__context_id, 
        check_object_ancestors__security_inherit_p
   from acs_objects
   where object_id = check_object_ancestors__ancestor_id;

   if check_object_ancestors__ancestor_id = 0 then
     if check_object_ancestors__context_id is null then
       result := ''t'';
     else
       -- This can be a constraint, can''''t it?
       PERFORM acs_log__error(''acs_object.check_representation'',
                     ''Object 0 doesn''''t have a null context_id'');
       result := ''f'';
     end if;
   else
     if check_object_ancestors__context_id is null or 
        check_object_ancestors__security_inherit_p = ''f'' 
     THEN
       check_object_ancestors__context_id := 0;
     end if;

     if acs_object__check_context_index(check_object_ancestors__object_id, 
                                        check_object_ancestors__ancestor_id, 
                                        check_object_ancestors__n_generations) = ''f'' then
       result := ''f'';
     end if;

     if acs_object__check_object_ancestors(check_object_ancestors__object_id, 
                                           check_object_ancestors__context_id,
	                      check_object_ancestors__n_generations + 1) = ''f'' then
       result := ''f'';
     end if;
   end if;

   return result;
  
end;' language 'plpgsql';


-- function check_object_descendants
create function acs_object__check_object_descendants (integer,integer,integer)
returns boolean as '
declare
  object_id              alias for $1;  
  descendant_id          alias for $2;  
  n_generations          alias for $3;  
  result                 boolean;     
  obj                    record;  
begin
   -- OBJECT_ID is the object we are verifying.
   -- DESCENDANT_ID is the current descendant we are tracking.
   -- N_GENERATIONS is how far the current DESCENDANT_ID is from
   -- OBJECT_ID.

   -- This function will verfy that each actualy descendant of
   -- OBJECT_ID has a row in the index table. It does not check that
   -- there aren''t extraneous rows or that the ancestors of OBJECT_ID
   -- are maintained correctly.

   result := ''t'';

   -- First verify that OBJECT_ID and DESCENDANT_ID are actually in
   -- the index.
   if acs_object__check_context_index(descendant_id, object_id, n_generations) = ''f'' then
     result := ''f'';
   end if;

   -- For every child that reports inheriting from OBJECT_ID we need to call
   -- ourselves recursively.
   for obj in  select *
	       from acs_objects
	       where context_id = descendant_id
	       and security_inherit_p = ''t'' loop
     if acs_object__check_object_descendants(object_id, obj.object_id,
       n_generations + 1) = ''f'' then
       result := ''f'';
     end if;
   end loop;

   return result;
  
end;' language 'plpgsql';


-- function check_path
create function acs_object__check_path (integer,integer)
returns boolean as '
declare
  check_path__object_id              alias for $1;  
  check_path__ancestor_id            alias for $2;  
  check_path__context_id             acs_objects.context_id%TYPE;
  check_path__security_inherit_p     acs_objects.security_inherit_p%TYPE;
begin
   if check_path__object_id = check_path__ancestor_id then
     return ''t'';
   end if;

   select context_id, security_inherit_p 
   into check_path__context_id, check_path__security_inherit_p
   from acs_objects
   where object_id = check_path__object_id;

   -- we should be able to handle the case where check_path fails 
   -- should we not?

   if check_path__object_id = 0 and check_path__context_id is null then 
      return ''f'';
   end if;

   if check_path__context_id is null or check_path__security_inherit_p = ''f'' 
   then
     check_path__context_id := 0;
   end if;

   return acs_object__check_path(check_path__context_id, 
                                 check_path__ancestor_id);
  
end;' language 'plpgsql';


-- function check_representation
create function acs_object__check_representation (integer)
returns boolean as '
declare
  check_representation__object_id              alias for $1;  
  result                                       boolean;       
  check_representation__object_type            acs_objects.object_type%TYPE;
  n_rows                                       integer;    
  v_rec                                        record;  
  row                                          record; 
begin
   result := ''t'';
   PERFORM acs_log__notice(''acs_object.check_representation'',
                  ''Running acs_object.check_representation on object_id = '' 
                  || check_representation__object_id || ''.'');

   select object_type into check_representation__object_type
   from acs_objects
   where object_id = check_representation__object_id;

   PERFORM acs_log__notice(''acs_object.check_representation'',
                  ''OBJECT STORAGE INTEGRITY TEST'');

   for v_rec in  select t.object_type, t.table_name, t.id_column
             from acs_object_type_supertype_map m, acs_object_types t
	     where m.ancestor_type = t.object_type
	     and m.object_type = check_representation__object_type
	     union
	     select object_type, table_name, id_column
	     from acs_object_types
	     where object_type = check_representation__object_type 
     LOOP

        for row in execute ''select case when count(*) = 0 then 0 else 1 end as n_rows from '' || quote_ident(v_rec.table_name) || '' where '' || quote_ident(v_rec.id_column) || '' = '' || check_representation__object_id
        LOOP
            n_rows := row.n_rows;
            exit;
        end LOOP;

        if n_rows = 0 then
           result := ''f'';
           PERFORM acs_log__error(''acs_object.check_representation'',
                     ''Table '' || v_rec.table_name || 
                     '' (primary storage for '' ||
		     v_rec.object_type || 
                     '') doesn''''t have a row for object '' ||
		     check_representation__object_id || '' of type '' || 
                     check_representation__object_type || ''.'');
        end if;

   end loop;

   PERFORM acs_log__notice(''acs_object.check_representation'',
                  ''OBJECT CONTEXT INTEGRITY TEST'');

   if acs_object__check_object_ancestors(check_representation__object_id, 
                                         check_representation__object_id, 0) = ''f'' then
     result := ''f'';
   end if;

   if acs_object__check_object_descendants(check_representation__object_id, 
                                           check_representation__object_id, 0) = ''f'' then
     result := ''f'';
   end if;
   for row in  select object_id, ancestor_id, n_generations
	       from acs_object_context_index
	       where object_id = check_representation__object_id
	       or ancestor_id = check_representation__object_id 
   LOOP
     if acs_object__check_path(row.object_id, row.ancestor_id) = ''f'' then
       PERFORM acs_log__error(''acs_object.check_representation'',
		     ''acs_object_context_index contains an extraneous row: ''
                     || ''object_id = '' || row.object_id || 
                     '', ancestor_id = '' || row.ancestor_id || 
                     '', n_generations = '' || row.n_generations || ''.'');
       result := ''f'';
     end if;
   end loop;

   PERFORM acs_log__notice(''acs_object.check_representation'',
		  ''Done running acs_object.check_representation '' || 
		  ''on object_id = '' || check_representation__object_id || ''.'');

   return result;
  
end;' language 'plpgsql';



-- show errors

-------------------
-- MISCELLANEOUS --
-------------------

create table general_objects (
	object_id		integer not null
				constraint general_objects_object_id_fk
				references acs_objects (object_id)
				constraint general_objects_pk
				primary key,
	on_which_table		varchar(30) not null,
	on_what_id		integer not null,
	constraint general_objects_un
		unique (on_which_table, on_what_id)
);

comment on table general_objects is '
 This table can be used to treat non-acs_objects as acs_objects for
 purposes of access control, categorization, etc.
';