(* Interface to Perl from OCaml.
 * Copyright (C) 2003 Merjis Ltd.
 * $Id: perl.ml,v 1.15 2005-04-14 13:05:12 rich Exp $
 *)

type sv
type av
type hv

exception Perl_failure of string

(* Initialization. This must happen first, otherwise other parts of the
 * program will segfault because of a missing interpreter.
 *)
external c_init : unit -> unit = "perl4caml_init"
let () =
  Callback.register_exception "perl4caml_perl_failure" (Perl_failure "");
  c_init ();				(* Initialise C code. *)
  ()

external int_of_sv : sv -> int = "perl4caml_int_of_sv"
external sv_of_int : int -> sv = "perl4caml_sv_of_int"
external float_of_sv : sv -> float = "perl4caml_float_of_sv"
external sv_of_float : float -> sv = "perl4caml_sv_of_float"
external string_of_sv : sv -> string = "perl4caml_string_of_sv"
external sv_of_string : string -> sv = "perl4caml_sv_of_string"
external sv_is_true : sv -> bool = "perl4caml_sv_is_true"
external sv_undef : unit -> sv = "perl4caml_sv_undef"
external sv_is_undef : sv -> bool = "perl4caml_sv_is_undef"
external sv_yes : unit -> sv = "perl4caml_sv_yes"
external sv_no : unit -> sv = "perl4caml_sv_no"

let sv_true () = sv_of_int 1
let sv_false () = sv_of_int 0

let bool_of_sv = sv_is_true
let sv_of_bool b = if b then sv_true () else sv_false ()

type sv_t    = SVt_NULL
             | SVt_IV
	     | SVt_NV
	     | SVt_PV
	     | SVt_RV
	     | SVt_PVAV
	     | SVt_PVHV
	     | SVt_PVCV
	     | SVt_PVGV
	     | SVt_PVMG

external sv_type : sv -> sv_t = "perl4caml_sv_type"

let string_of_sv_t = function
    SVt_NULL  -> "SVt_NULL"
  | SVt_IV    -> "SVt_IV"
  | SVt_NV    -> "SVt_NV"
  | SVt_PV    -> "SVt_PV"
  | SVt_RV    -> "SVt_RV"
  | SVt_PVAV  -> "SVt_PVAV"
  | SVt_PVHV  -> "SVt_PVHV"
  | SVt_PVCV  -> "SVt_PVCV"
  | SVt_PVGV  -> "SVt_PVGV"
  | SVt_PVMG  -> "SVt_PVMG"

external reftype : sv -> sv_t = "perl4caml_reftype"

external address_of_sv : sv -> Nativeint.t = "perl4caml_address_of_sv"
external address_of_av : av -> Nativeint.t = "perl4caml_address_of_av"
external address_of_hv : hv -> Nativeint.t = "perl4caml_address_of_hv"

external scalarref : sv -> sv = "perl4caml_scalarref"
external arrayref : av -> sv = "perl4caml_arrayref"
external hashref : hv -> sv = "perl4caml_hashref"

external deref : sv -> sv = "perl4caml_deref"
external deref_array : sv -> av = "perl4caml_deref_array"
external deref_hash : sv -> hv = "perl4caml_deref_hash"

external av_empty : unit -> av = "perl4caml_av_empty"
external av_of_sv_list : sv list -> av = "perl4caml_av_of_sv_list"
external av_push : av -> sv -> unit = "perl4caml_av_push"
external av_pop : av -> sv = "perl4caml_av_pop"
external av_shift : av -> sv = "perl4caml_av_shift"
external av_unshift : av -> sv -> unit = "perl4caml_av_unshift"
external av_length : av -> int = "perl4caml_av_length"
external av_set : av -> int -> sv -> unit = "perl4caml_av_set"
external av_get : av -> int -> sv = "perl4caml_av_get"
external av_clear : av -> unit = "perl4caml_av_clear"
external av_undef : av -> unit = "perl4caml_av_undef"
external av_extend : av -> int -> unit = "perl4caml_av_extend"

let av_map f av =
  let list = ref [] in
  for i = 0 to av_length av - 1 do
    list := f (av_get av i) :: !list
  done;
  List.rev !list

let list_of_av av =
  let list = ref [] in
  for i = 0 to av_length av - 1 do
    list := av_get av i :: !list
  done;
  List.rev !list

let av_of_string_list strs =
  av_of_sv_list (List.map sv_of_string strs)

external hv_empty : unit -> hv = "perl4caml_hv_empty"
external hv_set : hv -> string -> sv -> unit = "perl4caml_hv_set"
external hv_get : hv -> string -> sv = "perl4caml_hv_get"
external hv_exists : hv -> string -> bool = "perl4caml_hv_exists"
external hv_delete : hv -> string -> unit = "perl4caml_hv_delete"
external hv_clear : hv -> unit = "perl4caml_hv_clear"
external hv_undef : hv -> unit = "perl4caml_hv_undef"

type he
external hv_iterinit : hv -> Int32.t = "perl4caml_hv_iterinit"
external hv_iternext : hv -> he = "perl4caml_hv_iternext"
external hv_iterkey : he -> string = "perl4caml_hv_iterkey"
external hv_iterval : hv -> he -> sv = "perl4caml_hv_iterval"
external hv_iternextsv : hv -> string * sv = "perl4caml_hv_iternextsv"

let hv_of_assoc xs =
  let hv = hv_empty () in
  List.iter (fun (k, v) -> hv_set hv k v) xs;
  hv
let assoc_of_hv hv =
  ignore (hv_iterinit hv);
  (* Someone please rewrite this to make it tail-rec! - Rich. XXX *)
  let rec loop acc =
    try
      let k, v = hv_iternextsv hv in
      loop ((k, v) :: acc)
    with
	Not_found -> acc
  in
  loop []
let hv_keys hv =
  ignore (hv_iterinit hv);
  (* Someone please rewrite this to make it tail-rec! - Rich. XXX *)
  let rec loop acc =
    try
      let he = hv_iternext hv in
      let k = hv_iterkey he in
      loop (k :: acc)
    with
	Not_found -> acc
  in
  loop []
let hv_values hv =
  ignore (hv_iterinit hv);
  (* Someone please rewrite this to make it tail-rec! - Rich. XXX *)
  let rec loop acc =
    try
      let he = hv_iternext hv in
      let v = hv_iterval hv he in
      loop (v :: acc)
    with
	Not_found -> acc
  in
  loop []

external get_sv : ?create:bool -> string -> sv = "perl4caml_get_sv"
external get_av : ?create:bool -> string -> av = "perl4caml_get_av"
external get_hv : ?create:bool -> string -> hv = "perl4caml_get_hv"

external call : ?sv:sv -> ?fn:string -> sv list -> sv
  = "perl4caml_call"
external call_array : ?sv:sv -> ?fn:string -> sv list -> sv list
  = "perl4caml_call_array"
external call_void : ?sv:sv -> ?fn:string -> sv list -> unit
  = "perl4caml_call_void"

external eval : string -> sv
  = "perl4caml_eval"

external call_method : sv -> string -> sv list -> sv
  = "perl4caml_call_method"
external call_method_array : sv -> string -> sv list -> sv list
  = "perl4caml_call_method_array"
external call_method_void : sv -> string -> sv list -> unit
  = "perl4caml_call_method_void"
external call_class_method : string -> string -> sv list -> sv
  = "perl4caml_call_class_method"
external call_class_method_array : string -> string -> sv list -> sv list
  = "perl4caml_call_class_method_array"
external call_class_method_void : string -> string -> sv list -> unit
  = "perl4caml_call_class_method_void"