(*  Title:      HOL/Tools/Sledgehammer/sledgehammer.ML

     Author:     Fabian Immler, TU Muenchen

     Author:     Makarius

     Author:     Jasmin Blanchette, TU Muenchen

 Sledgehammer's heart.

 *)

 signature SLEDGEHAMMER =

 sig

   type failure = ATP_Systems.failure

   type relevance_override = Sledgehammer_Fact_Filter.relevance_override

   type minimize_command = Sledgehammer_Proof_Reconstruct.minimize_command

   type params =

     {debug: bool,

      verbose: bool,

      overlord: bool,

      atps: string list,

      full_types: bool,

      explicit_apply: bool,

      relevance_threshold: real,

      relevance_convergence: real,

      theory_relevant: bool option,

      defs_relevant: bool,

      isar_proof: bool,

      isar_shrink_factor: int,

      timeout: Time.time,

      minimize_timeout: Time.time}

   type problem =

     {subgoal: int,

      goal: Proof.context * (thm list * thm),

      relevance_override: relevance_override,

      axioms: (string * thm) list option}

   type prover_result =

     {outcome: failure option,

      message: string,

      pool: string Symtab.table,

      used_thm_names: string list,

      atp_run_time_in_msecs: int,

      output: string,

      proof: string,

      axiom_names: string Vector.vector,

      conjecture_shape: int list list}

   type prover = params -> minimize_command -> problem -> prover_result

   val dest_dir : string Config.T

   val problem_prefix : string Config.T

   val measure_runtime : bool Config.T

   val kill_atps: unit -> unit

   val running_atps: unit -> unit

   val messages: int option -> unit

   val get_prover_fun : theory -> string -> prover

   val run_sledgehammer :

     params -> int -> relevance_override -> (string -> minimize_command)

     -> Proof.state -> unit

   val setup : theory -> theory

 end;

 structure Sledgehammer : SLEDGEHAMMER =

 struct

 open ATP_Problem

 open ATP_Systems

 open Metis_Clauses

 open Sledgehammer_Util

 open Sledgehammer_Fact_Filter

 open Sledgehammer_Translate

 open Sledgehammer_Proof_Reconstruct

 (** The Sledgehammer **)

 (* Identifier to distinguish Sledgehammer from other tools using

    "Async_Manager". *)

 val das_Tool = "Sledgehammer"

 fun kill_atps () = Async_Manager.kill_threads das_Tool "ATPs"

 fun running_atps () = Async_Manager.running_threads das_Tool "ATPs"

 val messages = Async_Manager.thread_messages das_Tool "ATP"

 (** problems, results, provers, etc. **)

 type params =

   {debug: bool,

    verbose: bool,

    overlord: bool,

    atps: string list,

    full_types: bool,

    explicit_apply: bool,

    relevance_threshold: real,

    relevance_convergence: real,

    theory_relevant: bool option,

    defs_relevant: bool,

    isar_proof: bool,

    isar_shrink_factor: int,

    timeout: Time.time,

    minimize_timeout: Time.time}

 type problem =

   {subgoal: int,

    goal: Proof.context * (thm list * thm),

    relevance_override: relevance_override,

    axioms: (string * thm) list option}

 type prover_result =

   {outcome: failure option,

    message: string,

    pool: string Symtab.table,

    used_thm_names: string list,

    atp_run_time_in_msecs: int,

    output: string,

    proof: string,

    axiom_names: string Vector.vector,

    conjecture_shape: int list list}

 type prover = params -> minimize_command -> problem -> prover_result

 (* configuration attributes *)

 val (dest_dir, dest_dir_setup) = Attrib.config_string "atp_dest_dir" (K "");

   (*Empty string means create files in Isabelle's temporary files directory.*)

 val (problem_prefix, problem_prefix_setup) =

   Attrib.config_string "atp_problem_prefix" (K "prob");

 val (measure_runtime, measure_runtime_setup) =

   Attrib.config_bool "atp_measure_runtime" (K false);

 fun with_path cleanup after f path =

   Exn.capture f path

   |> tap (fn _ => cleanup path)

   |> Exn.release

   |> tap (after path)

 (* Splits by the first possible of a list of delimiters. *)

 fun extract_proof delims output =

   case pairself (find_first (fn s => String.isSubstring s output))

                 (ListPair.unzip delims) of

     (SOME begin_delim, SOME end_delim) =>

     (output |> first_field begin_delim |> the |> snd

             |> first_field end_delim |> the |> fst

             |> first_field "\n" |> the |> snd

      handle Option.Option => "")

   | _ => ""

 fun extract_proof_and_outcome complete res_code proof_delims known_failures

                               output =

   case known_failure_in_output output known_failures of

     NONE => (case extract_proof proof_delims output of

              "" => ("", SOME MalformedOutput)

            | proof => if res_code = 0 then (proof, NONE)

                       else ("", SOME UnknownError))

   | SOME failure =>

     ("", SOME (if failure = IncompleteUnprovable andalso complete then

                  Unprovable

                else

                  failure))

 fun extract_clause_sequence output =

   let

     val tokens_of = String.tokens (not o Char.isAlphaNum)

     fun extract_num ("clause" :: (ss as _ :: _)) =

     Int.fromString (List.last ss)

       | extract_num _ = NONE

   in output |> split_lines |> map_filter (extract_num o tokens_of) end

 val set_ClauseFormulaRelationN = "set_ClauseFormulaRelation"

 val parse_clause_formula_pair =

   $$ "(" |-- scan_integer --| $$ "," -- Symbol.scan_id

   --| Scan.repeat ($$ "," |-- Symbol.scan_id) --| $$ ")"

   --| Scan.option ($$ ",")

 val parse_clause_formula_relation =

   Scan.this_string set_ClauseFormulaRelationN |-- $$ "("

   |-- Scan.repeat parse_clause_formula_pair

 val extract_clause_formula_relation =

   Substring.full

   #> Substring.position set_ClauseFormulaRelationN

   #> snd #> Substring.string #> strip_spaces #> explode

   #> parse_clause_formula_relation #> fst

 fun repair_conjecture_shape_and_theorem_names output conjecture_shape

                                               thm_names =

   if String.isSubstring set_ClauseFormulaRelationN output then

     (* This is a hack required for keeping track of axioms after they have been

        clausified by SPASS's Flotter tool. The "SPASS_TPTP" script is also part

        of this hack. *)

     let

       val j0 = hd (hd conjecture_shape)

       val seq = extract_clause_sequence output

       val name_map = extract_clause_formula_relation output

       fun renumber_conjecture j =

         AList.find (op =) name_map (conjecture_prefix ^ Int.toString (j - j0))

         |> map (fn s => find_index (curry (op =) s) seq + 1)

     in

       (conjecture_shape |> map (maps renumber_conjecture),

        seq |> map (fn j => case j |> AList.lookup (op =) name_map |> the

                                   |> try (unprefix axiom_prefix) of

                              SOME s' => undo_ascii_of s'

                            | NONE => "")

            |> Vector.fromList)

     end

   else

     (conjecture_shape, thm_names)

 (* generic TPTP-based provers *)

 fun prover_fun atp_name

         {exec, required_execs, arguments, proof_delims, known_failures,

          max_new_relevant_facts_per_iter, prefers_theory_relevant,

          explicit_forall}

         ({debug, verbose, overlord, full_types, explicit_apply,

           relevance_threshold, relevance_convergence, theory_relevant,

           defs_relevant, isar_proof, isar_shrink_factor, timeout, ...} : params)

         minimize_command

         ({subgoal, goal, relevance_override, axioms} : problem) =

   let

     val (ctxt, (_, th)) = goal;

     val thy = ProofContext.theory_of ctxt

     val (params, hyp_ts, concl_t) = strip_subgoal th subgoal

     fun print s = (priority s; if debug then tracing s else ())

     fun print_v f = () |> verbose ? print o f

     fun print_d f = () |> debug ? print o f

     val the_axioms =

       case axioms of

         SOME axioms => axioms

       | NONE =>

         (print_d (fn () => "Selecting relevant facts for " ^ quote atp_name ^

                            ".");

          relevant_facts full_types relevance_threshold relevance_convergence

                         defs_relevant max_new_relevant_facts_per_iter

                         (the_default prefers_theory_relevant theory_relevant)

                         relevance_override goal hyp_ts concl_t

          |> tap ((fn n => print_v (fn () =>

                       "Selected " ^ string_of_int n ^ " fact" ^ plural_s n ^

                       " for " ^ quote atp_name ^ ".")) o length))

     (* path to unique problem file *)

     val the_dest_dir = if overlord then getenv "ISABELLE_HOME_USER"

                        else Config.get ctxt dest_dir;

     val the_problem_prefix = Config.get ctxt problem_prefix;

     fun prob_pathname nr =

       let

         val probfile =

           Path.basic ((if overlord then "prob_" ^ atp_name

                        else the_problem_prefix ^ serial_string ())

                       ^ "_" ^ string_of_int nr)

       in

         if the_dest_dir = "" then File.tmp_path probfile

         else if File.exists (Path.explode the_dest_dir)

         then Path.append (Path.explode the_dest_dir) probfile

         else error ("No such directory: " ^ the_dest_dir ^ ".")

       end;

     val command = Path.explode (getenv (fst exec) ^ "/" ^ snd exec)

     (* write out problem file and call prover *)

     fun command_line complete probfile =

       let

         val core = File.shell_path command ^ " " ^ arguments complete timeout ^

                    " " ^ File.shell_path probfile

       in

         (if Config.get ctxt measure_runtime then

            "TIMEFORMAT='%3U'; { time " ^ core ^ " ; }"

          else

            "exec " ^ core) ^ " 2>&1"

       end

     fun split_time s =

       let

         val split = String.tokens (fn c => str c = "\n");

         val (output, t) = s |> split |> split_last |> apfst cat_lines;

         fun as_num f = f >> (fst o read_int);

         val num = as_num (Scan.many1 Symbol.is_ascii_digit);

         val digit = Scan.one Symbol.is_ascii_digit;

         val num3 = as_num (digit ::: digit ::: (digit >> single));

         val time = num --| Scan.$$ "." -- num3 >> (fn (a, b) => a * 1000 + b);

         val as_time = the_default 0 o Scan.read Symbol.stopper time o explode;

       in (output, as_time t) end;

     fun run_on probfile =

       case filter (curry (op =) "" o getenv o fst) (exec :: required_execs) of

         (home_var, _) :: _ =>

         error ("The environment variable " ^ quote home_var ^ " is not set.")

       | [] =>

         if File.exists command then

           let

             fun do_run complete =

               let

                 val command = command_line complete probfile

                 val ((output, msecs), res_code) =

                   bash_output command

                   |>> (if overlord then

                          prefix ("% " ^ command ^ "\n% " ^ timestamp () ^ "\n")

                        else

                          I)

                   |>> (if Config.get ctxt measure_runtime then split_time

                        else rpair 0)

                 val (proof, outcome) =

                   extract_proof_and_outcome complete res_code proof_delims

                                             known_failures output

               in (output, msecs, proof, outcome) end

             val _ = print_d (fn () => "Preparing problem for " ^

                                       quote atp_name ^ "...")

             val readable_names = debug andalso overlord

             val (problem, pool, conjecture_offset, axiom_names) =

               prepare_problem ctxt readable_names explicit_forall full_types

                               explicit_apply hyp_ts concl_t the_axioms

             val _ = File.write_list probfile (strings_for_tptp_problem problem)

             val conjecture_shape =

               conjecture_offset + 1 upto conjecture_offset + length hyp_ts + 1

               |> map single

             val _ = print_d (fn () => "Running " ^ quote atp_name ^ "...")

             val result =

               do_run false

               |> (fn (_, msecs0, _, SOME _) =>

                      do_run true

                      |> (fn (output, msecs, proof, outcome) =>

                             (output, msecs0 + msecs, proof, outcome))

                    | result => result)

           in ((pool, conjecture_shape, axiom_names), result) end

         else

           error ("Bad executable: " ^ Path.implode command ^ ".")

     (* If the problem file has not been exported, remove it; otherwise, export

        the proof file too. *)

     fun cleanup probfile =

       if the_dest_dir = "" then try File.rm probfile else NONE

     fun export probfile (_, (output, _, _, _)) =

       if the_dest_dir = "" then

         ()

       else

         File.write (Path.explode (Path.implode probfile ^ "_proof")) output

     val ((pool, conjecture_shape, axiom_names),

          (output, msecs, proof, outcome)) =

       with_path cleanup export run_on (prob_pathname subgoal)

     val (conjecture_shape, axiom_names) =

       repair_conjecture_shape_and_theorem_names output conjecture_shape

                                                 axiom_names

     val (message, used_thm_names) =

       case outcome of

         NONE =>

         proof_text isar_proof

             (pool, debug, isar_shrink_factor, ctxt, conjecture_shape)

             (full_types, minimize_command, proof, axiom_names, th, subgoal)

       | SOME failure => (string_for_failure failure ^ "\n", [])

   in

     {outcome = outcome, message = message, pool = pool,

      used_thm_names = used_thm_names, atp_run_time_in_msecs = msecs,

      output = output, proof = proof, axiom_names = axiom_names,

      conjecture_shape = conjecture_shape}

   end

 fun get_prover_fun thy name = prover_fun name (get_prover thy name)

 fun start_prover_thread (params as {verbose, full_types, timeout, ...}) i n

                         relevance_override minimize_command proof_state

                         atp_name =

   let

     val thy = Proof.theory_of proof_state

     val birth_time = Time.now ()

     val death_time = Time.+ (birth_time, timeout)

     val prover = get_prover_fun thy atp_name

     val {context = ctxt, facts, goal} = Proof.goal proof_state;

     val desc =

       "ATP " ^ quote atp_name ^ " for subgoal " ^ string_of_int i ^ ":\n" ^

       Syntax.string_of_term ctxt (Thm.term_of (Thm.cprem_of goal i));

   in

     Async_Manager.launch das_Tool verbose birth_time death_time desc

         (fn () =>

             let

               val problem =

                 {subgoal = i, goal = (ctxt, (facts, goal)),

                  relevance_override = relevance_override, axioms = NONE}

             in

               prover params (minimize_command atp_name) problem |> #message

               handle ERROR message => "Error: " ^ message ^ "\n"

                    | exn => "Internal error: \n" ^ ML_Compiler.exn_message exn ^

                             "\n"

             end)

   end

 fun run_sledgehammer {atps = [], ...} _ _ _ _ = error "No ATP is set."

   | run_sledgehammer (params as {atps, ...}) i relevance_override

                      minimize_command state =

     case subgoal_count state of

       0 => priority "No subgoal!"

     | n =>

       let

         val _ = kill_atps ()

         val _ = priority "Sledgehammering..."

         val _ = app (start_prover_thread params i n relevance_override

                                          minimize_command state) atps

       in () end

 val setup =

   dest_dir_setup

   #> problem_prefix_setup

   #> measure_runtime_setup

 end;