-- create or replace package body workflow 
-- function create_workflow
create function workflow__create_workflow (varchar,varchar,varchar,varchar,varchar,varchar)
returns varchar as '
declare
  create_workflow__workflow_key    alias for $1;  
  create_workflow__pretty_name     alias for $2;  
  create_workflow__pretty_plural   alias for $3;  -- default null  
  create_workflow__description     alias for $4;  -- default null
  create_workflow__table_name      alias for $5;  
  create_workflow__id_column       alias for $6;  -- default ''case_id''
  v_num_rows                       integer;
  v_workflow_key                   varchar;
begin
        select count(*) into v_num_rows 
        from pg_class
        where relname = lower(create_workflow__table_name);

        if v_num_rows = 0 then
            raise EXCEPTION ''-20000: The table "%"must be created before calling workflow.create_workflow.'', create_workflow__table_name;
        end if;

        if substr(create_workflow__workflow_key, 
                  length(create_workflow__workflow_key) - 2, 3) != ''_wf'' then
            v_workflow_key := create_workflow__workflow_key || ''_wf'';
        else
            v_workflow_key := create_workflow__workflow_key;
        end if;

        PERFORM acs_object_type__create_type (
            v_workflow_key, 
            create_workflow__pretty_name, 
            create_workflow__pretty_plural,
            ''workflow'',
            create_workflow__table_name,
            create_workflow__id_column,
            null,
            ''f'',
            null,
            null
        );

        insert into wf_workflows 
            (workflow_key, description) 
        values 
            (v_workflow_key, create_workflow__description);

        return v_workflow_key;
     
end;' language 'plpgsql';


/* Note: The workflow-specific cases table must be dropped before calling this proc */
create function workflow__drop_workflow (varchar)
returns integer as '
declare
  drop_workflow__workflow_key      alias for $1;  
  v_table_name                     varchar;  
  v_num_rows                       integer;        
  attribute_rec                    record;
begin
        select table_name into v_table_name 
        from   acs_object_types
        where  object_type = drop_workflow__workflow_key;

        select case when count(*) = 0 then 0 else 1 end into v_num_rows 
        from   pg_class
        where  relname = lower(v_table_name);

        if v_num_rows > 0 then
            raise EXCEPTION ''-20000: The table "%" must be dropped before calling workflow__drop_workflow.'', v_table_name;
        end if;

        select case when count(*) = 0 then 0 else 1 end into v_num_rows 
        from   wf_cases
        where  workflow_key = drop_workflow__workflow_key;

        if v_num_rows > 0 then
            raise EXCEPTION ''-20000: You must delete all cases of workflow "%" before dropping the workflow definition.'', drop_workflow__workflow_key;
        end if;

        /* Delete all the auxillary stuff */
        delete from wf_context_task_panels where workflow_key = drop_workflow__workflow_key;
        delete from wf_context_assignments where workflow_key = drop_workflow__workflow_key;
        delete from wf_context_role_info where workflow_key = drop_workflow__workflow_key; 
        delete from wf_context_transition_info where workflow_key = drop_workflow__workflow_key; 
        delete from wf_context_workflow_info where workflow_key = drop_workflow__workflow_key;
        delete from wf_arcs where workflow_key = drop_workflow__workflow_key;
        delete from wf_places where workflow_key = drop_workflow__workflow_key;
	delete from wf_transition_role_assign_map where workflow_key = drop_workflow__workflow_key;
	delete from wf_transitions where workflow_key = drop_workflow__workflow_key;
        delete from wf_roles where workflow_key = drop_workflow__workflow_key;

        /* Drop all attributes */
        for attribute_rec in 
        select attribute_id, attribute_name 
        from acs_attributes 
        where object_type = drop_workflow__workflow_key
        LOOP
            /* there is no on delete cascade, so we have to manually 
             * delete all the values 
             */

            delete from acs_attribute_values where attribute_id = attribute_rec.attribute_id;

            PERFORM workflow__drop_attribute (
                drop_workflow__workflow_key,
                attribute_rec.attribute_name
            );
        end loop;

        /* Delete the workflow */
        delete from wf_workflows where workflow_key = drop_workflow__workflow_key;
        
        PERFORM acs_object_type__drop_type (
            drop_workflow__workflow_key,
            ''f''
        );

        return 0; 
end;' language 'plpgsql';


-- procedure delete_cases
create function workflow__delete_cases (varchar)
returns integer as '
declare
  delete_cases__workflow_key       alias for $1; 
  case_rec                         record; 
begin
        for case_rec in 
            select case_id 
            from wf_cases 
            where workflow_key = delete_cases__workflow_key
        LOOP
            PERFORM workflow_case__delete(case_rec.case_id);
        end loop;

        return 0; 
end;' language 'plpgsql';


-- function create_attribute
create function workflow__create_attribute (varchar,varchar,varchar,varchar,varchar,varchar,varchar,varchar,integer,integer,integer,varchar)
returns integer as '
declare
  create_attribute__workflow_key   alias for $1;  
  create_attribute__attribute_name alias for $2;  
  create_attribute__datatype       alias for $3;  
  create_attribute__pretty_name    alias for $4;  
  create_attribute__pretty_plural  alias for $5;  -- default null  
  create_attribute__table_name     alias for $6;  -- default null
  create_attribute__column_name    alias for $7;  -- default null
  create_attribute__default_value  alias for $8;  -- default null
  create_attribute__min_n_values   alias for $9;  -- default 1
  create_attribute__max_n_values   alias for $10; -- default 1
  create_attribute__sort_order     alias for $11; -- default null
  create_attribute__storage        alias for $12; -- default ''generic''
  v_attribute_id                   integer;        
begin
        v_attribute_id := acs_attribute__create_attribute(
            create_attribute__workflow_key,
            create_attribute__attribute_name,
            create_attribute__datatype,
            create_attribute__pretty_name,
            create_attribute__pretty_plural,
            create_attribute__table_name,
            create_attribute__column_name,
            create_attribute__default_value,
            create_attribute__min_n_values,
            create_attribute__max_n_values,
            create_attribute__sort_order,
            create_attribute__storage,
            ''f''
        );

        return v_attribute_id;
     
end;' language 'plpgsql';


-- procedure drop_attribute
create function workflow__drop_attribute (varchar,varchar)
returns integer as '
declare
  drop_attribute__workflow_key     alias for $1;  
  drop_attribute__attribute_name   alias for $2;  
  v_attribute_id                   integer;        
begin
        select attribute_id into v_attribute_id
        from   acs_attributes
        where  object_type = drop_attribute__workflow_key
        and    attribute_name = drop_attribute__attribute_name;

        PERFORM acs_attribute__drop_attribute (
            drop_attribute__workflow_key,
            drop_attribute__attribute_name
        );

        return 0; 
end;' language 'plpgsql';


-- procedure add_place
create function workflow__add_place (varchar,varchar,varchar,integer)
returns integer as '
declare
  add_place__workflow_key          alias for $1;  
  add_place__place_key             alias for $2;  
  add_place__place_name            alias for $3;  
  add_place__sort_order            alias for $4; 
  v_sort_order			   integer; 
begin
        if add_place__sort_order is null then
            select coalesce(max(sort_order)+1, 1)
              into v_sort_order
              from wf_places
             where workflow_key = add_place__workflow_key;
        else
            v_sort_order := add_place__sort_order;
        end if;
        insert into wf_places (workflow_key, place_key, place_name, sort_order)
        values (add_place__workflow_key, add_place__place_key,add_place__place_name, add_place__sort_order);

        return 0; 
end;' language 'plpgsql';


-- procedure delete_place
create function workflow__delete_place (varchar,varchar)
returns integer as '
declare
  delete_place__workflow_key       alias for $1;  
  delete_place__place_key          alias for $2;  
begin
        delete from wf_places
        where  workflow_key = delete_place__workflow_key 
        and    place_key = delete_place__place_key;

        return 0; 
end;' language 'plpgsql';


-- procedure add_role
create function workflow__add_role (varchar,varchar,varchar,integer)
returns integer as '
declare
  add_role__workflow_key	   alias for $1;
  add_role__role_key		   alias for $2;
  add_role__role_name		   alias for $3;
  add_role__sort_order		   alias for $4;
  v_sort_order			   integer;
begin
        if add_role__sort_order is null then
            select coalesce(max(sort_order)+1, 1)
              into v_sort_order
              from wf_roles
	     where workflow_key = add_role__workflow_key;
        else
            v_sort_order := add_role__sort_order;
        end if;
        insert into wf_roles (
            workflow_key, role_key, role_name, sort_order
        ) values (
            add_role__workflow_key, add_role__role_key, add_role__role_name, v_sort_order
        );
        return 0; 
end;' language 'plpgsql';


-- procedure move_role_up
create function workflow__move_role_up (varchar,varchar)
returns integer as '
declare
  move_role_up__workflow_key		alias for $1;
  move_role_up__role_key		alias for $2;
  v_this_sort_order			integer;
  v_prior_sort_order			integer;
begin
        select sort_order
          into v_this_sort_order
          from wf_roles
         where workflow_key = move_role_up__workflow_key
           and role_key = move_role_up__role_key;

        select max(sort_order) 
	  into v_prior_sort_order
	  from wf_roles
	where workflow_key = move_role_up__workflow_key
        and sort_order < v_this_sort_order;

	if not found then
            /* already at top of sort order */
	  return 0;
	end if;

	/* switch the sort orders around */
        update wf_roles
	   set sort_order = (case when role_key=move_role_up__role_key then v_prior_sort_order else v_this_sort_order end)
         where workflow_key = move_role_up__workflow_key
           and sort_order in (v_this_sort_order, v_prior_sort_order);

	return 0;
end;' language 'plpgsql';


-- procedure move_role_down
create function workflow__move_role_down (varchar,varchar)
returns integer as '
declare
  move_role_down__workflow_key		alias for $1;
  move_role_down__role_key		alias for $2;
  v_this_sort_order			integer;
  v_next_sort_order			integer;
begin
        select sort_order
          into v_this_sort_order
          from wf_roles
         where workflow_key = move_role_down__workflow_key
           and role_key = move_role_down__role_key;

        select min(sort_order)
	  into v_next_sort_order
	  from wf_roles
	 where workflow_key = move_role_down__workflow_key
	  and sort_order > v_this_sort_order;

	if not found then
            /* already at bottom of sort order */
	  return 0;
	end if;

        /* switch the sort orders around */
        update wf_roles
	   set sort_order = (case when role_key=move_role_down__role_key then v_next_sort_order else v_this_sort_order end)
         where workflow_key = move_role_down__workflow_key
           and sort_order in (v_this_sort_order, v_next_sort_order);

  return 0;
end;' language 'plpgsql';


-- procedure delete_role
create function workflow__delete_role (varchar,varchar)
returns integer as '
declare
  delete_role__workflow_key		alias for $1;
  delete_role__role_key			alias for $2;
begin
        /* First, remove all references to this role from transitions */
        update wf_transitions
	   set role_key = null
         where workflow_key = delete_role__workflow_key
	   and role_key = delete_role__role_key;

        delete from wf_roles
        where  workflow_key = delete_role__workflow_key
        and    role_key = delete_role__role_key;

	return 0;
end;' language 'plpgsql';


-- procedure add_transition
create function workflow__add_transition (varchar,varchar,varchar,varchar,integer,varchar)
returns integer as '
declare
  add_transition__workflow_key     alias for $1;  
  add_transition__transition_key   alias for $2;  
  add_transition__transition_name  alias for $3;  
  add_transition__role_key	   alias for $4;
  add_transition__sort_order       alias for $5;  
  add_transition__trigger_type     alias for $6;  -- default ''user''
  v_sort_order			   integer;
begin
        if add_transition__sort_order is null then
            select coalesce(max(sort_order)+1, 1)
              into v_sort_order
              from wf_transitions
             where workflow_key = add_transition__workflow_key;
        else
            v_sort_order := add_transition__sort_order;
        end if;
	insert into wf_transitions (
            workflow_key, 
            transition_key, 
            transition_name, 
            role_key,
            sort_order, 
            trigger_type
        ) values (
            add_transition__workflow_key, 
            add_transition__transition_key, 
            add_transition__transition_name,
            add_transition__role_key,
	    v_sort_order, 
            add_transition__trigger_type
        );

        return 0; 
end;' language 'plpgsql';


-- procedure delete_transition
create function workflow__delete_transition (varchar,varchar)
returns integer as '
declare
  delete_transition__workflow_key       alias for $1;  
  delete_transition__transition_key     alias for $2;  
begin
        delete from wf_transitions
        where  workflow_key = delete_transition__workflow_key
        and    transition_key = delete_transition__transition_key;

        return 0; 
end;' language 'plpgsql';


-- procedure add_arc
create function workflow__add_arc (varchar,varchar,varchar,varchar,varchar,varchar,varchar)
returns integer as '
declare
  add_arc__workflow_key            alias for $1;  
  add_arc__transition_key          alias for $2;  
  add_arc__place_key               alias for $3;  
  add_arc__direction               alias for $4;  
  add_arc__guard_callback          alias for $5;  -- default null  
  add_arc__guard_custom_arg        alias for $6;  -- default null
  add_arc__guard_description       alias for $7;  -- default null
begin
        insert into wf_arcs (workflow_key, transition_key, place_key, direction,
        guard_callback, guard_custom_arg, guard_description)
        values (add_arc__workflow_key, add_arc__transition_key, add_arc__place_key, add_arc__direction,
        add_arc__guard_callback, add_arc__guard_custom_arg, add_arc__guard_description);

        return 0; 
end;' language 'plpgsql';


-- procedure add_arc
create function workflow__add_arc (varchar,varchar,varchar,varchar,varchar,varchar)
returns integer as '
declare
  add_arc__workflow_key		alias for $1;
  add_arc__from_transition_key	alias for $2;
  add_arc__to_place_key		alias for $3;
  add_arc__guard_callback	alias for $4;
  add_arc__guard_custom_arg	alias for $5;
  add_arc__guard_description	alias for $6;
begin
  perform workflow__add_arc (
	    add_arc__workflow_key,
	    add_arc__from_transition_key,
	    add_arc__to_place_key,
	    ''out'',
	    add_arc__guard_callback,
	    add_arc__guard_custom_arg,
	    add_arc__guard_description
	  );

  return 0;
end;' language 'plpgsql';


-- procedure add_arc
create function workflow__add_arc (varchar,varchar,varchar)
returns integer as '
declare
  add_arc__workflow_key		alias for $1;
  add_arc__from_place_key	alias for $2;
  add_arc__to_transition_key	alias for $3;
begin
  perform workflow__add_arc(
	    add_arc__workflow_key,
	    add_arc__to_transition_key,
	    add_arc__from_place_key,
	    ''in'',
	    null,
	    null,
	    null
	  );	 

  return 0;
end;' language 'plpgsql';


-- procedure delete_arc
create function workflow__delete_arc (varchar,varchar,varchar,varchar)
returns integer as '
declare
  delete_arc__workflow_key         alias for $1;  
  delete_arc__transition_key       alias for $2;  
  delete_arc__place_key            alias for $3;  
  delete_arc__direction            alias for $4;  
begin
        delete from wf_arcs
        where  workflow_key = delete_arc__workflow_key
        and    transition_key = delete_arc__transition_key
        and    place_key = delete_arc__place_key
        and    direction = delete_arc__direction;

        return 0; 
end;' language 'plpgsql';



-- procedure add_trans_attribute_map
create function workflow__add_trans_attribute_map (varchar,varchar,integer,integer)
returns integer as '
declare
  p_workflow_key		alias for $1;
  p_transition_key		alias for $2; 
  p_attribute_id		alias for $3;
  p_sort_order			alias for $4;
  v_num_rows			integer;
  v_sort_order			integer;
begin
        select count(*)
          into v_num_rows
          from wf_transition_attribute_map
         where workflow_key = p_workflow_key
	   and transition_key = p_transition_key
	   and attribute_id = p_attribute_id;

        if v_num_rows > 0 then
            return 0;
        end if;
        if p_sort_order is null then
            select coalesce(max(sort_order)+1, 1)
              into v_sort_order
              from wf_transition_attribute_map
             where workflow_key = p_workflow_key
               and transition_key = p_transition_key;
        else
            v_sort_order := p_sort_order;
        end if;
        insert into wf_transition_attribute_map (
            workflow_key,
            transition_key,
            attribute_id,
            sort_order
        ) values (
            p_workflow_key,
	    p_transition_key,
            p_attribute_id,
            v_sort_order
       );

  return 0;

end;' language 'plpgsql';



-- procedure add_trans_attribute_map
create function workflow__add_trans_attribute_map (varchar,varchar,varchar,integer)
returns integer as '
declare
  p_workflow_key		alias for $1;
  p_transition_key		alias for $2;
  p_attribute_name		alias for $3;
  p_sort_order			alias for $4;
  v_attribute_id		integer;
begin
        select attribute_id
          into v_attribute_id
          from acs_attributes
         where object_type = p_workflow_key
           and attribute_name = p_attribute_name;

        perform workflow__add_trans_attribute_map (
		  p_workflow_key,
		  p_transition_key,
		  v_attribute_id,
		  p_sort_order
        );

	return 0;

end;' language 'plpgsql';


-- procedure delete_trans_attribute_map
create function workflow__delete_trans_attribute_map (varchar,varchar,integer)
returns integer as '
declare
  p_workflow_key		alias for $1;
  p_transition_key		alias for $2;
  p_attribute_id            alias for $3;
begin
        delete
          from wf_transition_attribute_map
         where workflow_key = p_workflow_key
           and transition_key = p_transition_key
           and attribute_id = p_attribute_id;

  return 0;
end;' language 'plpgsql';

-- procedure delete_trans_attribute_map
create function workflow__delete_trans_attribute_map (varchar,varchar,varchar)
returns integer as '
declare
  p_workflow_key		alias for $1;
  p_transition_key		alias for $2;
  p_attribute_name		alias for $3;
  v_attribute_id		integer;
begin
        select attribute_id
          into v_attribute_id
          from acs_attributes
         where object_type = p_workflow_key
           and attribute_name = p_attribute_name;

        delete
          from wf_transition_attribute_map
         where workflow_key = p_workflow_key
           and transition_key = p_transition_key
           and attribute_id = v_attribute_id;

  return 0;
end;' language 'plpgsql';


-- procedure add_trans_role_assign_map
create function workflow__add_trans_role_assign_map (varchar,varchar,varchar)
returns integer as '
declare
  p_workflow_key		alias for $1;
  p_transition_key		alias for $2;
  p_assign_role_key		alias for $3;
  v_num_rows			integer;
begin
        select count(*)
          into v_num_rows
          from wf_transition_role_assign_map
	 where workflow_key = p_workflow_key
           and transition_key = p_transition_key
           and assign_role_key = p_assign_role_key;

        if v_num_rows = 0 then
	    insert into wf_transition_role_assign_map (
		workflow_key,
		transition_key,
		assign_role_key
	    ) values (
		p_workflow_key,
		p_transition_key,
		p_assign_role_key
	    );
        end if;

	return 0;
end;' language 'plpgsql';

-- procedure delete_trans_role_assign_map
create function workflow__delete_trans_role_assign_map (varchar,varchar,varchar)
returns integer as '
declare
  p_workflow_key		alias for $1;
  p_transition_key		alias for $2;
  p_assign_role_key		alias for $3;
begin
        delete
          from wf_transition_role_assign_map
         where workflow_key = p_workflow_key
           and transition_key = p_transition_key
           and assign_role_key = p_assign_role_key;

	   return 0;
end;' language 'plpgsql';



create sequence workflow_session_id;

create table previous_place_list (
               session_id integer,
               rcnt       integer,
               constraint previous_place_list_pk
               primary key (session_id, rcnt),
               ky         varchar(100)
);

create table target_place_list (
               session_id integer,
               rcnt       integer,
               constraint target_place_list_pk
               primary key (session_id, rcnt),
               ky         varchar(100)
);

create table guard_list (
               session_id integer,
               rcnt       integer,
               constraint quard_list_pk 
               primary key (session_id, rcnt),
               ky         varchar(100)
);

create function workflow__simple_p (varchar)
returns boolean as '
declare
  simple_p__workflow_key           alias for $1;  
  v_session_id                     integer;
  retval                           boolean;
begin
      v_session_id := nextval(''workflow_session_id'');
      retval := __workflow__simple_p(simple_p__workflow_key, v_session_id);

      delete from previous_place_list where session_id = v_session_id;
      delete from target_place_list where session_id = v_session_id;
      delete from guard_list where session_id = v_session_id;

      return retval;

end;' language 'plpgsql';

-- function simple_p

create function __workflow__simple_p (varchar,integer)
returns boolean as '
declare
  simple_p__workflow_key           alias for $1;  
  v_session_id                     alias for $2;
  -- previous_place_list              t_place_table; 
  -- target_place_list                t_place_table; 
  -- guard_list                       t_guard_table; 
  guard_list_1                     varchar;
  guard_list_2                     varchar;
  target_place_list_1              varchar;
  target_place_list_2              varchar;
  previous_place_list_i            varchar;
  v_row_count                      integer default 0;       
  v_count                          integer;       
  v_count2                         integer;       
  v_place_key                      wf_places.place_key%TYPE;
  v_end_place                      wf_places.place_key%TYPE;
  v_transition_key                 wf_transitions.transition_key%TYPE;
  v_rownum                         integer;
  v_target                         record;
begin

        /* Let us do some simple checks first */

        /* Places with more than one arc out */
        select count(*) into v_count
        from   wf_places p
        where  p.workflow_key = simple_p__workflow_key
        and    1 < (select count(*) 
                    from   wf_arcs a
                    where  a.workflow_key = p.workflow_key
                    and    a.place_key = p.place_key
                    and    direction = ''in'');
        raise notice ''query 1'';
        if v_count > 0 then
            return ''f'';
        end if;

        /* Transitions with more than one arc in */
        select count(*) into v_count
        from   wf_transitions t
        where  t.workflow_key = simple_p__workflow_key
        and    1 < (select count(*)
                    from   wf_arcs a
                    where  a.workflow_key = t.workflow_key
                    and    a.transition_key = t.transition_key
                    and    direction = ''in'');

        raise notice ''query 2'';
        if v_count > 0 then
            return ''f'';
        end if;

        /* Transitions with more than two arcs out */
        select count(*) into v_count
        from   wf_transitions t
        where  t.workflow_key = simple_p__workflow_key
        and    2 < (select count(*)
                    from   wf_arcs a
                    where  a.workflow_key = t.workflow_key
                    and    a.transition_key = t.transition_key
                    and    direction = ''out'');

        raise notice ''query 3'';
        if v_count > 0 then
            return ''f'';
        end if;

        /* Now we do the more complicated checks.
         * We keep a list of visited places because I could not think
         * of a nicer way that was not susceptable to infinite loops.
         */


        v_place_key := ''start'';
        v_end_place := ''end'';

        loop
            exit when v_place_key = v_end_place;

            -- previous_place_list(v_row_count) := v_place_key;
            insert into previous_place_list 
            (session_id,rcnt,ky) 
            values 
            (v_session_id,v_row_count,v_place_key);
        raise notice ''query 4'';

            select distinct transition_key into v_transition_key
            from   wf_arcs
            where  workflow_key = simple_p__workflow_key
            and    place_key = v_place_key
            and    direction = ''in'';
        raise notice ''query 5'';

            select count(*) into v_count
            from wf_arcs
            where workflow_key = simple_p__workflow_key
            and   transition_key = v_transition_key
            and   direction = ''out'';
        raise notice ''query 6'';

            if v_count = 1 then
                select distinct place_key into v_place_key
                from wf_arcs
                where workflow_key = simple_p__workflow_key
                and   transition_key = v_transition_key
                and   direction = ''out'';
        raise notice ''query 7'';

            else if v_count = 0 then
                /* deadend! */
                return ''f'';

            else
                /* better be two based on our earlier test */

                v_rownum := 1;
                for v_target in 
                select place_key,guard_callback
                from   wf_arcs
                where  workflow_key = simple_p__workflow_key
                and    transition_key = v_transition_key
                and    direction = ''out''
                LOOP
                    -- target_place_list(v_target.rownum) := v_target.place_key;
        raise notice ''query 8'';
                    insert into target_place_list 
                    (session_id,rcnt,ky) 
                    values 
                    (v_session_id,v_rownum,v_target.place_key);
        raise notice ''query 9'';

                    -- guard_list(v_target.rownum) := v_target.guard_callback; 
                    insert into guard_list 
                    (session_id,rcnt,ky) 
                    values 
                    (v_session_id,v_rownum,v_target.guard_callback);
                    v_rownum := v_rownum + 1;
        raise notice ''query 10'';
                end loop;
    
                /* Check that the guard functions are the negation of each other 
                 * by looking for the magic entry "#" (exactly once)
                 */
                select ky into guard_list_1 from guard_list 
                where session_id = v_session_id and rcnt = 1;
        raise notice ''query 11'';

                select ky into guard_list_2 from guard_list 
                where session_id = v_session_id and rcnt = 2;
        raise notice ''query 12'';

                if ((guard_list_1 != ''#'' and guard_list_2 != ''#'') or
                    (guard_list_1 = ''#'' and guard_list_2 = ''#'')) then
                    return ''f'';
                end if;
    
                /* Check that exactly one of the targets is in the previous list */

                v_count2 := 0;
                select ky into target_place_list_1 from target_place_list 
                where session_id = v_session_id and rcnt = 1;
        raise notice ''query 13'';

                select ky into target_place_list_2 from target_place_list 
                where session_id = v_session_id and rcnt = 2;                
        raise notice ''query 14'';

                for i in 0..v_row_count LOOP
                    select ky into previous_place_list_i 
                    from previous_place_list where session_id = v_session_id 
                    and rcnt = i;
                    if target_place_list_1 = previous_place_list_i then
                        v_count2 := v_count2 + 1;
                        v_place_key := target_place_list_2;
                    end if;
                    if target_place_list_2 = previous_place_list_i then
                        v_count2 := v_count2 + 1;
                        v_place_key := target_place_list_1;
                    end if;
                end loop;
        raise notice ''query 15'';

                if v_count2 != 1 then
                    return ''f'';
                end if;

            end if; end if;

            v_row_count := v_row_count + 1;

        end loop;

        /* if we got here, it must be okay */
        return ''t'';

     
end;' language 'plpgsql';

-- show errors