let time f a msg =
  let t0 = Unix.gettimeofday () in
  let r = f a in
  let t1 = Unix.gettimeofday () in
    Printf.printf "Timing %s: %f ms\n" msg ((t1 -. t0) *. 1000.);
    r



type pointers
type allocation_order = PREORDER | INORDER | POSTORDER
external build_pointers : Tree.t -> allocation_order -> pointers = "caml_build_pointers"
external iter_pointers : pointers -> int = "caml_iter_pointers"
external free_pointers : pointers -> unit = "caml_free_pointers"

let string_of_alloc =
  function
      PREORDER -> "preorder"
    | INORDER -> "inorder"
    | POSTORDER -> "postorder"


let test_pointers alloc v =
  let size = Tree.subtree_size v Tree.root in
    if ((size * (Sys.word_size/8)*2) / (1024*1024)) >= 2800
    then Printf.printf "Not enough memory to allocate pointer with %i nodes\n%!" size
    else begin
      let msg1 = Printf.sprintf "pointer structure %s allocation" (string_of_alloc alloc) in
      let pointers = time (build_pointers v) alloc msg1 in
      let i = time (iter_pointers) pointers "pointer structure full traversal" in
	Printf.printf "Traversed %i nodes\n" i;
	time (free_pointers) pointers "pointer structure deallocation"
    end
;;

let test_iterative v =
  let i = time (Tree.benchmark_iter) v "iterative traversal (on sxsi)" in
    Printf.printf "Traversed %i nodes\n%!" i

let test_full_traversal v =
  let i = time (Tree.benchmark_fcns) v "recursive traversal (on sxsi)" in
    Printf.printf "Traversed %i nodes\n%!" i

let test_full_elements v =
  let i = time (Tree.benchmark_fene) v "recursive traversal of element nodes (on sxsi)" in
    Printf.printf "Traversed %i nodes\n%!" i

let test_tag_jump v t =
  let msg = Printf.sprintf "jumping to tag <%s> (on sxsi)" (Tag.to_string t) in
  let i = time (Tree.benchmark_jump v) t msg in
    Printf.printf "Traversed %i nodes\n%!" i


module Options =
  struct
    open Arg
    let input_file = ref ""
    let save_file = ref ""
    let run_iterative = ref false
    let run_full_sxsi = ref false
    let run_elements = ref false
    let run_pointers = ref []
    let run_jump_tag = ref ""

    let add_pointer t =
      let tag = match t with
	| "preorder" -> PREORDER
	| "inorder" -> INORDER
	| "postorder" -> POSTORDER
	| _ -> raise (Bad (t))
      in
	if not (List.mem tag !run_pointers) then run_pointers := tag :: !run_pointers


    let spec = align
      [ "-s", Set_string save_file, "<output.srx> saves the index in file output.srx";
	"-i", Set run_iterative, " runs the iterative full traversal (on sxsi)";
	"-f", Set run_full_sxsi, " runs the recursive full traversal (on sxsi)";
	"-e", Set run_elements, " simulates //* on sxsi";
	"-p", Symbol ([ "preorder"; "inorder"; "postorder" ],
		      add_pointer), "runs a full traveral over pointers with given allocation scheme";
	"-t", Set_string run_jump_tag, "<tag> simulates //tag on sxsi" ]

    let usage_msg = Printf.sprintf "%s [options] <input.{xml|srx}>" Sys.argv.(0)
    let parse () = parse spec (fun s -> input_file := s) usage_msg
    let usage () = usage spec usage_msg
  end

let fail msg = Printf.eprintf "error: %s%!" msg; Options.usage (); exit 1

let line () = Printf.printf "\n%!"

let main () =
  Options.parse ();
  if !Options.input_file = "" then fail "missing input file";
  let ifile = !Options.input_file in
  let doc =
    if Filename.check_suffix ifile ".srx" then
      Tree.load ifile
    else Tree.parse_xml_uri ifile in
    if !Options.save_file <> "" then begin
      Printf.printf "Saving index to %s ... %!" !Options.save_file;
      Tree.save doc !Options.save_file;
      Printf.printf "done\n%!"
    end;
    Tag.init (Tree.tag_pool doc);
    line ();
    if !Options.run_iterative then (test_iterative doc; line ());

    if !Options.run_full_sxsi then (test_full_traversal doc; line ());

    if !Options.run_elements then (test_full_elements doc; line ());

    if !Options.run_jump_tag <> "" then (test_tag_jump doc (Tag.tag  !Options.run_jump_tag);
					line ());

    if !Options.run_pointers <> [] then
      List.iter (fun s -> test_pointers s doc; line ())
      !Options.run_pointers;

    exit 0
;;

let _ =
  let () = Printexc.record_backtrace true in
    try
      main ()
    with
	_ ->
	  let msg = Printexc.get_backtrace () in
	  Printf.eprintf "%s\n%!" msg;
	  exit 3