1		:- multifile generate/2.
2		:- multifile shrink/3.
3
4		:- use_module(library(random),[random/3]).
5		:- use_module(library(avl),[list_to_avl/2, avl_to_list/2]).
6		:- use_module(library(lists)).
7
8		% Options:
9		% not-well-defined-values, size:S, list, avl or none for random value sequence
10
11		% any type
12		generate(prob_value_seq(Options),Value) :-
13		is_list(Options) ,
14		generate(ground_type,Type) ,
15		generate(prob_value_seq(Type,Options),Value).
16		% no options
17		generate(prob_value_seq(Type),Value) :-
18		generate(prob_value_seq(Type,[]),Value).
19
20		generate(prob_value_seq(Type,Options),Value) :-
21		(member(not-well-defined,Options)
22		-> delete(Options,not-well-defined,T) ,
23		TOptions = [not-well-defined-values|T]
24		; TOptions = Options) ,
25		(member(size:Size,TOptions)
26		-> true
27		; random(1,20,Size)) ,
28		gen_type(Type,value,NType) ,
29		length(List,Size) ,
30		maplist(generate(NType),List) ,
31		(member(not-well-defined-values,TOptions)
32		-> maplist(gen_random_indexed_couple,List,CoupleList)
33		; remove_dups(List,NList) ,
34		gen_indexed_couple_list(1,NList,CoupleList)) ,
35		% random choice of list set or avl set if no option is given
36		random(0,2,R) ,
37		( \+member(list,TOptions) , (member(avl,TOptions) ; R = 0)
38		-> % add key to every element to use list_to_avl
39		findall(Key-true,member(Key,CoupleList),Pairs) ,
40		list_to_avl(Pairs,AVL) ,
41		Value = avl_set(AVL)
42		; % else list sequence
43		Value = CoupleList).
44
45		% replace each list element with an indexed couple, starting at 1
46		gen_indexed_couple_list(_,[],[]).
47		gen_indexed_couple_list(C,[Elm|T],[(int(C),Elm)|NT]) :-
48		C1 is C + 1 ,
49		gen_indexed_couple_list(C1,T,NT).
50
51		% use for no well-definedness
52		gen_random_indexed_couple(Value,(Index,Value)) :-
53		generate(prob_value_integer([small]),Index).
54
55		shrink(Type,avl_set(Value),avl_set(Shrunken)) :-
56		Type =..[prob_value_seq|_] ,
57		avl_to_list(Value,AVLList) ,
58		findall(Key,member(Key-_,AVLList),SeqList) ,
59		shrink(prob_value_seq,SeqList,NewSeqList) ,
60		findall(Key-true,member(Key,NewSeqList),NewAVL) ,
61		list_to_avl(NewAVL,Shrunken).
62
63		shrink(Type,Value,Shrunken) :-
64		Type =..[prob_value_seq|_] ,
65		findall(Val,member((_,Val),Value),ValueList) ,
66		shrink(list,ValueList,ShrunkenList) ,
67		gen_indexed_couple_list(1,ShrunkenList,Shrunken).