(*  Title:      HOL/Mutabelle/mutabelle_extra.ML

     Author:     Stefan Berghofer, Jasmin Blanchette, Lukas Bulwahn, TU Muenchen

 Invokation of Counterexample generators.

 *)

 signature MUTABELLE_EXTRA =

 sig

 val take_random : int -> 'a list -> 'a list

 datatype outcome = GenuineCex | PotentialCex | NoCex | Donno | Timeout | Error | Solved | Unsolved

 type timings = (string * int) list

 type mtd = string * (theory -> term -> outcome * timings)

 type mutant_subentry = term * (string * (outcome * timings)) list

 type detailed_entry = string * bool * term * mutant_subentry list

 type subentry = string * int * int * int * int * int * int

 type entry = string * bool * subentry list

 type report = entry list

 val quickcheck_mtd : (Proof.context -> Proof.context) -> string -> mtd

 val solve_direct_mtd : mtd

 val try_mtd : mtd

 (*

 val sledgehammer_mtd : mtd

 *)

 val nitpick_mtd : mtd

 (*

 val refute_mtd : mtd

 *)

 val freezeT : term -> term

 val thms_of : bool -> theory -> thm list

 val string_for_report : report -> string

 val write_report : string -> report -> unit

 val mutate_theorems_and_write_report :

   theory -> mtd list -> thm list -> string -> unit

 val random_seed : real Unsynchronized.ref

 end;

 structure MutabelleExtra : MUTABELLE_EXTRA =

 struct

 (* Own seed; can't rely on the Isabelle one to stay the same *)

 val random_seed = Unsynchronized.ref 1.0;

 (* mutation options *)

 (*val max_mutants = 4

 val num_mutations = 1*)

 (* soundness check: *)

 val max_mutants =  10

 val num_mutations = 1

 (* quickcheck options *)

 (*val quickcheck_generator = "SML"*)

 (* Another Random engine *)

 exception RANDOM;

 fun rmod x y = x - y * Real.realFloor (x / y);

 local

   val a = 16807.0;

   val m = 2147483647.0;

 in

 fun random () = CRITICAL (fn () =>

   let val r = rmod (a * ! random_seed) m

   in (random_seed := r; r) end);

 end;

 fun random_range l h =

   if h < l orelse l < 0 then raise RANDOM

   else l + Real.floor (rmod (random ()) (real (h - l + 1)));

 fun take_random 0 _ = []

   | take_random _ [] = []

   | take_random n xs =

     let val j = random_range 0 (length xs - 1) in

       Library.nth xs j :: take_random (n - 1) (nth_drop j xs)

     end

 (* possible outcomes *)

 datatype outcome = GenuineCex | PotentialCex | NoCex | Donno | Timeout | Error | Solved | Unsolved

 fun string_of_outcome GenuineCex = "GenuineCex"

   | string_of_outcome PotentialCex = "PotentialCex"

   | string_of_outcome NoCex = "NoCex"

   | string_of_outcome Donno = "Donno"

   | string_of_outcome Timeout = "Timeout"

   | string_of_outcome Error = "Error"

   | string_of_outcome Solved = "Solved"

   | string_of_outcome Unsolved = "Unsolved"

 type timings = (string * int) list

 type mtd = string * (theory -> term -> outcome * timings)

 type mutant_subentry = term * (string * (outcome * timings)) list

 type detailed_entry = string * bool * term * mutant_subentry list

 type subentry = string * int * int * int * int * int * int

 type entry = string * bool * subentry list

 type report = entry list

 (* possible invocations *)

 (** quickcheck **)

 fun invoke_quickcheck change_options quickcheck_generator thy t =

   TimeLimit.timeLimit (seconds (!Auto_Tools.time_limit))

       (fn _ =>

           let

             val [result] = Quickcheck.test_goal_terms (change_options (Proof_Context.init_global thy))

               (false, false) [] [(t, [])]

           in

             case Quickcheck.counterexample_of result of 

               NONE => (NoCex, Quickcheck.timings_of result)

             | SOME _ => (GenuineCex, Quickcheck.timings_of result)

           end) ()

   handle TimeLimit.TimeOut =>

          (Timeout, [("timelimit", Real.floor (!Auto_Tools.time_limit))])

 fun quickcheck_mtd change_options quickcheck_generator =

   ("quickcheck_" ^ quickcheck_generator, invoke_quickcheck change_options quickcheck_generator)

 (** solve direct **)

 fun invoke_solve_direct thy t =

   let

     val state = Proof.theorem NONE (K I) (map (single o rpair []) [t]) (Proof_Context.init_global thy) 

   in

     case Solve_Direct.solve_direct false state of

       (true, _) => (Solved, [])

     | (false, _) => (Unsolved, [])

   end

 val solve_direct_mtd = ("solve_direct", invoke_solve_direct) 

 (** try **)

 fun invoke_try thy t =

   let

     val state = Proof.theorem NONE (K I) (map (single o rpair []) [t]) (Proof_Context.init_global thy)

   in

     case Try.invoke_try (SOME (seconds 5.0)) ([], [], [], []) state of

       true => (Solved, [])

     | false => (Unsolved, [])

   end

 val try_mtd = ("try", invoke_try)

 (** sledgehammer **)

 (*

 fun invoke_sledgehammer thy t =

   if can (Goal.prove_global thy (Term.add_free_names t [])  [] t)

       (fn {context, ...} => Sledgehammer_Tactics.sledgehammer_with_metis_tac context 1) then

     (Solved, ([], NONE))

   else

     (Unsolved, ([], NONE))

 val sledgehammer_mtd = ("sledgehammer", invoke_sledgehammer)

 *)

 (*

 fun invoke_refute thy t =

   let

     val res = MyRefute.refute_term thy [] t

     val _ = Output.urgent_message ("Refute: " ^ res)

   in

     case res of

       "genuine" => GenuineCex

     | "likely_genuine" => GenuineCex

     | "potential" => PotentialCex

     | "none" => NoCex

     | "unknown" => Donno

     | _ => Error

   end

   handle MyRefute.REFUTE (loc, details) =>

          (error ("Unhandled Refute error (" ^ quote loc ^ "): " ^ details ^

                    "."))

 val refute_mtd = ("refute", invoke_refute)

 *)

 (** nitpick **)

 fun invoke_nitpick thy t =

   let

     val ctxt = Proof_Context.init_global thy

     val state = Proof.init ctxt

     val (res, _) = Nitpick.pick_nits_in_term state

       (Nitpick_Isar.default_params thy []) false 1 1 1 [] [] t

     val _ = Output.urgent_message ("Nitpick: " ^ res)

   in

     (rpair []) (case res of

       "genuine" => GenuineCex

     | "likely_genuine" => GenuineCex

     | "potential" => PotentialCex

     | "none" => NoCex

     | "unknown" => Donno

     | _ => Error)

   end

 val nitpick_mtd = ("nitpick", invoke_nitpick)

 (* filtering forbidden theorems and mutants *)

 val comms = [@{const_name HOL.eq}, @{const_name HOL.disj}, @{const_name HOL.conj}]

 val forbidden =

  [(* (@{const_name "power"}, "'a"), *)

   (*(@{const_name induct_equal}, "'a"),

   (@{const_name induct_implies}, "'a"),

   (@{const_name induct_conj}, "'a"),*)

   (@{const_name "undefined"}, "'a"),

   (@{const_name "default"}, "'a"),

   (@{const_name "dummy_pattern"}, "'a::{}"),

   (@{const_name "HOL.simp_implies"}, "prop => prop => prop"),

   (@{const_name "bot_fun_inst.bot_fun"}, "'a"),

   (@{const_name "top_fun_inst.top_fun"}, "'a"),

   (@{const_name "Pure.term"}, "'a"),

   (@{const_name "top_class.top"}, "'a"),

   (@{const_name "Quotient.Quot_True"}, "'a")(*,

   (@{const_name "uminus"}, "'a"),

   (@{const_name "Nat.size"}, "'a"),

   (@{const_name "Groups.abs"}, "'a") *)]

 val forbidden_thms =

  ["finite_intvl_succ_class",

   "nibble"]

 val forbidden_consts =

  [@{const_name nibble_pair_of_char}, @{const_name "TYPE"}]

 fun is_forbidden_theorem (s, th) =

   let val consts = Term.add_const_names (prop_of th) [] in

     exists (member (op =) (space_explode "." s)) forbidden_thms orelse

     exists (member (op =) forbidden_consts) consts orelse

     length (space_explode "." s) <> 2 orelse

     String.isPrefix "type_definition" (List.last (space_explode "." s)) orelse

     String.isSuffix "_def" s orelse

     String.isSuffix "_raw" s orelse

     String.isPrefix "term_of" (List.last (space_explode "." s))

   end

 val forbidden_mutant_constnames =

  ["HOL.induct_equal",

   "HOL.induct_implies",

   "HOL.induct_conj",

  @{const_name undefined},

  @{const_name default},

  @{const_name dummy_pattern},

  @{const_name "HOL.simp_implies"},

  @{const_name "bot_fun_inst.bot_fun"},

  @{const_name "top_fun_inst.top_fun"},

  @{const_name "Pure.term"},

  @{const_name "top_class.top"},

  (*@{const_name "HOL.equal"},*)

  @{const_name "Quotient.Quot_True"},

  @{const_name "equal_fun_inst.equal_fun"},

  @{const_name "equal_bool_inst.equal_bool"},

  @{const_name "ord_fun_inst.less_eq_fun"},

  @{const_name "ord_fun_inst.less_fun"},

  @{const_name Metis.fequal},

  @{const_name Meson.skolem},

  @{const_name transfer_morphism}

  (*@{const_name "==>"}, @{const_name "=="}*)]

 val forbidden_mutant_consts =

   [

    (@{const_name "Groups.zero_class.zero"}, @{typ "prop => prop => prop"}),

    (@{const_name "Groups.one_class.one"}, @{typ "prop => prop => prop"}),

    (@{const_name "Groups.plus_class.plus"}, @{typ "prop => prop => prop"}),

    (@{const_name "Groups.minus_class.minus"}, @{typ "prop => prop => prop"}),

    (@{const_name "Groups.times_class.times"}, @{typ "prop => prop => prop"}),

    (@{const_name "Rings.inverse_class.divide"}, @{typ "prop => prop => prop"}),

    (@{const_name "Lattices.semilattice_inf_class.inf"}, @{typ "prop => prop => prop"}),

    (@{const_name "Lattices.semilattice_sup_class.sup"}, @{typ "prop => prop => prop"}),

    (@{const_name "Orderings.bot_class.bot"}, @{typ "prop => prop => prop"}),

    (@{const_name "Orderings.ord_class.min"}, @{typ "prop => prop => prop"}),

    (@{const_name "Orderings.ord_class.max"}, @{typ "prop => prop => prop"}),

    (@{const_name "Divides.div_class.mod"}, @{typ "prop => prop => prop"}),

    (@{const_name "Divides.div_class.div"}, @{typ "prop => prop => prop"}),

    (@{const_name "GCD.gcd_class.gcd"}, @{typ "prop => prop => prop"}),

    (@{const_name "GCD.gcd_class.lcm"}, @{typ "prop => prop => prop"}),

    (@{const_name "Orderings.bot_class.bot"}, @{typ "bool => prop"}),

    (@{const_name "Groups.one_class.one"}, @{typ "bool => prop"}),

    (@{const_name "Groups.zero_class.zero"},@{typ "bool => prop"})]

 fun is_forbidden_mutant t =

   let

     val const_names = Term.add_const_names t []

     val consts = Term.add_consts t []

   in

     exists (String.isPrefix "Nitpick") const_names orelse

     exists (String.isSubstring "_sumC") const_names orelse

     exists (member (op =) forbidden_mutant_constnames) const_names orelse

     exists (member (op =) forbidden_mutant_consts) consts

   end

 (* executable via quickcheck *)

 fun is_executable_term thy t =

   let

     val ctxt = Proof_Context.init_global thy

   in

     can (TimeLimit.timeLimit (seconds 2.0)

       (Quickcheck.test_goal_terms

         ((Config.put Quickcheck.finite_types true #>

           Config.put Quickcheck.finite_type_size 1 #>

           Config.put Quickcheck.size 1 #> Config.put Quickcheck.iterations 1) ctxt)

         (false, false) [])) (map (rpair [] o Object_Logic.atomize_term thy) (fst (Variable.import_terms true [t] ctxt)))

   end

 fun is_executable_thm thy th = is_executable_term thy (prop_of th)

 val freezeT =

   map_types (map_type_tvar (fn ((a, i), S) =>

     TFree (if i = 0 then a else a ^ "_" ^ string_of_int i, S)))

 fun thms_of all thy =

   filter

     (fn th => (all orelse Context.theory_name (theory_of_thm th) = Context.theory_name thy)

       (* andalso is_executable_thm thy th *))

     (map snd (filter_out is_forbidden_theorem (Mutabelle.all_unconcealed_thms_of thy)))

 fun count x = (length oo filter o equal) x

 fun cpu_time description e =

   let val ({cpu, ...}, result) = Timing.timing e ()

   in (result, (description, Time.toMilliseconds cpu)) end

 (*

 fun unsafe_invoke_mtd thy (mtd_name, invoke_mtd) t =

   let

     val _ = Output.urgent_message ("Invoking " ^ mtd_name)

     val ((res, (timing, reports)), time) = cpu_time "total time" (fn () => invoke_mtd thy t

       handle ERROR s => (tracing s; (Error, ([], NONE))))

     val _ = Output.urgent_message (" Done")

   in (res, (time :: timing, reports)) end

 *)  

 fun safe_invoke_mtd thy (mtd_name, invoke_mtd) t =

   let

     val _ = Output.urgent_message ("Invoking " ^ mtd_name)

     val (res, timing) = (*cpu_time "total time"

       (fn () => *)case try (invoke_mtd thy) t of

           SOME (res, timing) => (res, timing)

         | NONE => (Output.urgent_message ("**** PROBLEMS WITH " ^ Syntax.string_of_term_global thy t);

            (Error, []))

     val _ = Output.urgent_message (" Done")

   in (res, timing) end

 (* theory -> term list -> mtd -> subentry *)

 fun test_mutants_using_one_method thy mutants (mtd_name, invoke_mtd) =

   let

      val res = map (fst o safe_invoke_mtd thy (mtd_name, invoke_mtd)) mutants

   in

     (mtd_name, count GenuineCex res, count PotentialCex res, count NoCex res,

      count Donno res, count Timeout res, count Error res)

   end

 (* creating entries *)

 fun create_entry thy thm exec mutants mtds =

   (Thm.get_name_hint thm, exec, map (test_mutants_using_one_method thy mutants) mtds)

 fun create_detailed_entry thy thm exec mutants mtds =

   let

     fun create_mutant_subentry mutant = (mutant,

       map (fn (mtd_name, invoke_mtd) =>

         (mtd_name, safe_invoke_mtd thy (mtd_name, invoke_mtd) mutant)) mtds)

   in

     (Thm.get_name_hint thm, exec, prop_of thm, map create_mutant_subentry mutants)

   end

 (* (theory -> thm -> bool -> term list -> mtd list -> 'a) -> theory -> mtd list -> thm -> 'a *)

 fun mutate_theorem create_entry thy mtds thm =

   let

     val exec = is_executable_thm thy thm

     val _ = Output.tracing (if exec then "EXEC" else "NOEXEC")

     val mutants =

           (if num_mutations = 0 then

              [Thm.prop_of thm]

            else

              Mutabelle.mutate_mix (Thm.prop_of thm) thy comms forbidden

                                   num_mutations)

              |> tap (fn muts => tracing ("mutants: " ^ string_of_int (length muts)))

              |> filter_out is_forbidden_mutant

     val mutants =

       if exec then

         let

           val _ = Output.urgent_message ("BEFORE PARTITION OF " ^

                             string_of_int (length mutants) ^ " MUTANTS")

           val (execs, noexecs) = List.partition (is_executable_term thy) (take_random (20 * max_mutants) mutants)

           val _ = tracing ("AFTER PARTITION (" ^ string_of_int (length execs) ^

                            " vs " ^ string_of_int (length noexecs) ^ ")")

         in

           execs @ take_random (Int.max (0, max_mutants - length execs)) noexecs

         end

       else

         mutants

     val mutants = mutants

           |> map Mutabelle.freeze |> map freezeT

 (*          |> filter (not o is_forbidden_mutant) *)

           |> map_filter (try (Sign.cert_term thy))

           |> filter (is_some o try (Thm.cterm_of thy))

           |> filter (is_some o try (Syntax.check_term (Proof_Context.init_global thy)))

           |> take_random max_mutants

     val _ = map (fn t => Output.urgent_message ("MUTANT: " ^ Syntax.string_of_term_global thy t)) mutants

   in

     create_entry thy thm exec mutants mtds

   end

 (* theory -> mtd list -> thm list -> report *)

 val mutate_theorems = map ooo mutate_theorem

 fun string_of_mutant_subentry thy thm_name (t, results) =

   "mutant: " ^ Syntax.string_of_term_global thy t ^ "\n" ^

   space_implode "; "

     (map (fn (mtd_name, (outcome, timing)) => mtd_name ^ ": " ^ string_of_outcome outcome) results) ^

   "\n"

 (* string -> string *)

 val unyxml = XML.content_of o YXML.parse_body

 fun string_of_mutant_subentry' thy thm_name (t, results) =

   let

    (* fun string_of_report (Quickcheck.Report {iterations = i, raised_match_errors = e,

       satisfied_assms = s, positive_concl_tests = p}) =

       "errors: " ^ string_of_int e ^ "; conclusion tests: " ^ string_of_int p

     fun string_of_reports NONE = ""

       | string_of_reports (SOME reports) =

         cat_lines (map (fn (size, [report]) =>

           "size " ^ string_of_int size ^ ": " ^ string_of_report report) (rev reports))*)

     fun string_of_mtd_result (mtd_name, (outcome, timing)) =

       mtd_name ^ ": " ^ string_of_outcome outcome

       (*" with time " ^ " (" ^ space_implode "; " (map (fn (s, t) => (s ^ ": " ^ string_of_int t)) timing) ^ ")"*)

       (*^ "\n" ^ string_of_reports reports*)

   in

     "mutant of " ^ thm_name ^ ":\n"

     ^ unyxml (Syntax.string_of_term_global thy t) ^ "\n" ^ space_implode "; " (map string_of_mtd_result results)

   end

 fun string_of_detailed_entry thy (thm_name, exec, t, mutant_subentries) = 

    thm_name ^ " " ^ (if exec then "[exe]" else "[noexe]") ^ ": " ^

    Syntax.string_of_term_global thy t ^ "\n" ^                                    

    cat_lines (map (string_of_mutant_subentry' thy thm_name) mutant_subentries) ^ "\n"

 fun theoryfile_string_of_mutant_subentry thy thm_name (i, (t, results)) =

   "lemma " ^ thm_name ^ "_" ^ string_of_int (i + 1) ^ ":\n" ^

   "\"" ^ unyxml (Syntax.string_of_term_global thy t) ^

   "\" \nquickcheck\noops\n"

 fun theoryfile_string_of_detailed_entry thy (thm_name, exec, t, mutant_subentries) =

   "subsubsection {* mutants of " ^ thm_name ^ " *}\n\n" ^

   cat_lines (map_index

     (theoryfile_string_of_mutant_subentry thy thm_name) mutant_subentries) ^ "\n"

 (* subentry -> string *)

 fun string_for_subentry (mtd_name, genuine_cex, potential_cex, no_cex, donno,

                          timeout, error) =

   "    " ^ mtd_name ^ ": " ^ string_of_int genuine_cex ^ "+ " ^

   string_of_int potential_cex ^ "= " ^ string_of_int no_cex ^ "- " ^

   string_of_int donno ^ "? " ^ string_of_int timeout ^ "T " ^

   string_of_int error ^ "!"

 (* entry -> string *)

 fun string_for_entry (thm_name, exec, subentries) =

   thm_name ^ " " ^ (if exec then "[exe]" else "[noexe]") ^ ":\n" ^

   cat_lines (map string_for_subentry subentries) ^ "\n"

 (* report -> string *)

 fun string_for_report report = cat_lines (map string_for_entry report)

 (* string -> report -> unit *)

 fun write_report file_name =

   File.write (Path.explode file_name) o string_for_report

 (* theory -> mtd list -> thm list -> string -> unit *)

 fun mutate_theorems_and_write_report thy mtds thms file_name =

   let

     val _ = Output.urgent_message "Starting Mutabelle..."

     val ctxt = Proof_Context.init_global thy

     val path = Path.explode file_name

     (* for normal report: *)

     (*

     val (gen_create_entry, gen_string_for_entry) = (create_entry, string_for_entry)

     *)

     (* for detailled report: *)

     val (gen_create_entry, gen_string_for_entry) = (create_detailed_entry, string_of_detailed_entry thy)

     (* for theory creation: *)

     (*val (gen_create_entry, gen_string_for_entry) = (create_detailed_entry, theoryfile_string_of_detailed_entry thy)*)

   in

     File.write path (

     "Mutation options = "  ^

       "max_mutants: " ^ string_of_int max_mutants ^

       "; num_mutations: " ^ string_of_int num_mutations ^ "\n" ^

     "QC options = " ^

       (*"quickcheck_generator: " ^ quickcheck_generator ^ ";*)

       "size: " ^ string_of_int (Config.get ctxt Quickcheck.size) ^

       "; iterations: " ^ string_of_int (Config.get ctxt Quickcheck.iterations) ^ "\n");

     map (File.append path o gen_string_for_entry o mutate_theorem gen_create_entry thy mtds) thms;

     ()

   end

 end;