(* Memory info command for virtual domains.
   (C) Copyright 2008 Richard W.M. Jones, Red Hat Inc.
   http://libvirt.org/

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *)

open Camlp4.PreCast
open Syntax
(*open Ast*)

open ExtList
open ExtString
open Printf

module PP = Pahole_parser
module SC = Struct_classify

(* We don't care about locations when generating code, so it's
 * useful to just have a single global _loc.
 *)
let _loc = Loc.ghost

(* Some handy camlp4 construction functions which do some
 * things that ought to be easy/obvious but aren't.
 *
 * 'concat_str_items' concatenates a list of str_item together into
 * one big str_item.
 *
 * 'concat_record_fields' concatenates a list of records fields into
 * a record.  The list must have at least one element.
 *
 * 'build_record' builds a record out of record fields.
 * 
 * 'build_tuple_from_exprs' builds an arbitrary length tuple from
 * a list of expressions of length >= 2.
 *
 * Thanks to bluestorm on #ocaml for getting these working.
 *)
let concat_str_items items =
  match items with
  | [] -> <:str_item< >>
  | x :: xs ->
      List.fold_left (fun xs x -> <:str_item< $xs$ $x$ >>) x xs

let concat_sig_items items =
  match items with
  | [] -> <:sig_item< >>
  | x :: xs ->
      List.fold_left (fun xs x -> <:sig_item< $xs$ $x$ >>) x xs

let concat_record_fields fields =
  match fields with
    | [] -> assert false
    | f :: fs ->
	List.fold_left (fun fs f -> <:ctyp< $fs$ ; $f$ >>) f fs

let concat_record_bindings rbs =
  match rbs with
    | [] -> assert false
    | rb :: rbs ->
	List.fold_left (fun rbs rb -> <:rec_binding< $rbs$ ; $rb$ >>) rb rbs

let build_record rbs =
  Ast.ExRec (_loc, rbs, Ast.ExNil _loc)

let build_tuple_from_exprs exprs =
  match exprs with
  | [] | [_] -> assert false
  | x :: xs ->
      Ast.ExTup (_loc,
		 List.fold_left (fun xs x -> Ast.ExCom (_loc, x, xs)) x xs)

let ocaml_type_of_field_type = function
  | PP.FInteger -> <:ctyp< int64 >>
  | PP.FString _ -> <:ctyp< string >>
  | PP.FStructPointer _ | PP.FVoidPointer
  | PP.FAnonListHeadPointer | PP.FListHeadPointer _ ->
      <:ctyp< Virt_mem_mmap.addr >>

let generate_types xs =
  let strs = List.map (
    fun (struct_name, sflist, cflist) ->
      let sflist = List.map (
	fun { SC.sf_name = name; sf_fields = fields } ->
	  if fields <> [] then (
	    let fields = List.map (
	      fun { PP.field_name = name; PP.field_type = t } ->
		let t = ocaml_type_of_field_type t in
		<:ctyp< $lid:name$ : $t$ >>
	    ) fields in
	    let fields = concat_record_fields fields in

	    <:str_item<
	      type $lid:name$ = { $fields$ }
            >>
	  ) else
	    <:str_item< type $lid:name$ = unit >>
      ) sflist in
      let sflist = concat_str_items sflist in

      let cflist = List.map (
	fun { SC.cf_name = name; cf_fields = fields } ->
	  if fields <> [] then (
	    let fields = List.map (
	      fun { PP.field_name = name; PP.field_type = t } ->
		let t = ocaml_type_of_field_type t in
		<:ctyp< $lid:name$ : $t$ >>
	    ) fields in
	    let fields = concat_record_fields fields in

	    <:str_item<
	      type $lid:name$ = { $fields$ }
            >>
	  ) else
	    <:str_item< type $lid:name$ = unit >>
      ) cflist in
      let cflist = concat_str_items cflist in

      <:str_item<
        type ('a, 'b) $lid:struct_name$ = {
	  $lid:struct_name^"_shape"$ : 'a;
	  $lid:struct_name^"_content"$ : 'b;
	}
	$sflist$
	$cflist$
      >>
  ) xs in

  let sigs =
    List.map (
      fun (struct_name, _, _) ->
	<:sig_item<
          type ('a, 'b) $lid:struct_name$
	>>
    ) xs in

  concat_str_items strs, concat_sig_items sigs

let output_interf ~output_file types =
  let sigs = concat_sig_items [ types ] in
  Printers.OCaml.print_interf ~output_file sigs

let output_implem ~output_file types =
  let strs = concat_str_items [ types ] in
  Printers.OCaml.print_implem ~output_file strs