(******************************************************************************)
(*  SXSI : XPath evaluator                                                    *)
(*  Kim Nguyen (Kim.Nguyen@nicta.com.au)                                      *)
(*  Copyright NICTA 2008                                                      *)
(*  Distributed under the terms of the LGPL (see LICENCE)                     *)
(******************************************************************************)
INCLUDE "debug.ml"
module type BINARY =
sig
  type node_content
  type string_content
  type descr = Nil | Node of node_content  |String of string_content 
  type t
  val parse_xml_uri : string -> t
  val parse_xml_string : string -> t
  val save : t -> string -> unit
  val load : ?sample:int -> string -> t
  val tag_pool : t -> Tag.pool
  val string : t -> string
  val descr : t -> descr
  val is_node : t -> bool
  val left : t -> t
  val right : t -> t
  val first_child : t -> t
  val next_sibling : t -> t
  val parent : t -> t
  val root : t -> t
  val is_root : t -> bool
  val id : t -> int
  val tag : t -> Tag.t
  val print_xml_fast : out_channel -> t -> unit
  val compare : t -> t -> int
  val equal : t -> t -> bool
  module DocIdSet :
  sig 
    include Set.S 
  end
    with type elt = string_content
  val string_below : t -> string_content -> bool
  val contains : t -> string -> DocIdSet.t
  val contains_old : t -> string -> DocIdSet.t
  val contains_iter : t -> string -> DocIdSet.t
  val count_contains : t -> string -> int
  val count : t -> string -> int
  val dump : t -> unit
  val get_string : t -> string_content -> string
  val has_tagged_desc : t -> Tag.t -> bool
  val has_tagged_foll : t -> Tag.t -> bool
  val tagged_desc : t -> Tag.t -> t
  val tagged_foll : t -> Tag.t -> t
  val tagged_below : t -> Ptset.t -> Ptset.t -> t
  val tagged_next : t -> Ptset.t -> Ptset.t -> t -> t
  val tagged_desc_only : t -> Ptset.t -> t
  val tagged_foll_only : t -> Ptset.t -> t -> t
  val text_below : t -> t
  val text_next : t -> t -> t
  val init_tagged_next : t -> Tag.t -> unit
  val subtree_tags : t -> Tag.t -> int
  val is_left : t -> bool
  val print_id : Format.formatter -> t -> unit 
  val test_xml_tree : Format.formatter -> Ptset.t -> t -> unit
  val init_contains : t -> string -> unit
  val init_naive_contains : t -> string -> unit
  val mk_nil : t -> t
  val test_jump : t -> Tag.t -> unit
  val time_xml_tree : t -> Tag.t -> int list
  val time_xml_tree2 : t -> Tag.t -> int list
end

module XML = 
struct

  type t
  type 'a node = int
  type node_kind = [`Text | `Tree ]

  let compare : 'a node -> 'a node -> int = (-)
  let equal : 'a node -> 'a node -> bool = (==)

        (* abstract type, values are pointers to a XMLTree C++ object *)
    
  external int_of_node : 'a node -> int = "%identity"

  external parse_xml_uri : string -> int -> bool -> bool -> t = "caml_call_shredder_uri"         
  external parse_xml_string :  string -> int -> bool -> bool -> t = "caml_call_shredder_string"

  external save_tree : t -> string -> unit = "caml_xml_tree_save"
  external load_tree : string -> int -> t = "caml_xml_tree_load"


  module Text =
  struct
    let equal : [`Text] node -> [`Text] node -> bool = equal
      
    (* Todo *)
    external nullt : unit -> [`Text ] node = "caml_xml_tree_nullt"
    let nil = nullt ()
    external get_text : t -> [`Text] node -> string = "caml_text_collection_get_text"

(*    let get_text t n = 
      if equal nil n then "" 
      else  get_text t n
*)
		
    external is_empty : t -> [`Text ] node -> bool = "caml_text_collection_empty_text"

    let is_empty t n =
      (equal nil n) || is_empty t n

    external get_cached_text : t -> [`Text ] node -> string = "caml_text_collection_get_cached_text"
      

    let get_text t n =
      if equal nil n then ""
      else get_cached_text t n

    external size : t -> int = "caml_text_collection_size"
    external is_contains : t -> string -> bool = "caml_text_collection_is_contains"
    external count_contains : t -> string -> int = "caml_text_collection_count_contains"
    external count : t -> string -> int = "caml_text_collection_count"
    external contains : t -> string -> [`Text ] node array = "caml_text_collection_contains"
  end


  module Tree = 
  struct

    let equal : [`Tree ] node -> [`Tree] node -> bool = equal
    external serialize : t -> string -> unit = "caml_xml_tree_serialize"
    external unserialize : string -> t = "caml_xml_tree_unserialize"
      
    external root : t -> [`Tree] node = "caml_xml_tree_root"
    external nullt : unit -> [`Tree ] node = "caml_xml_tree_nullt"

    let nil = nullt ()
    let is_nil x = equal x nil

    external parent : t -> [`Tree] node -> [`Tree] node = "caml_xml_tree_parent"
    external parent_doc : t -> [`Text ] node -> [`Tree ] node = "caml_xml_tree_parent_doc"
    external prev_doc : t -> [`Text ] node -> [`Tree ] node = "caml_xml_tree_prev_doc"
    external first_child : t -> [`Tree] node -> [`Tree] node = "caml_xml_tree_first_child"
      

      
    external next_sibling : t -> [`Tree] node -> [`Tree] node = "caml_xml_tree_next_sibling"
    external prev_sibling : t -> [`Tree] node -> [`Tree] node = "caml_xml_tree_prev_sibling"
    external is_leaf : t  -> [`Tree] node -> bool = "caml_xml_tree_is_leaf"
    
(*    external tag : t -> [`Tree ] node -> T = "caml_xml_tree_tag"*)
    external tag_id : t -> [`Tree ] node -> Tag.t = "caml_xml_tree_tag_id"

(*
    let tag_hash = Array.make 6_000_000 (Tag.nullt)

    let tag_id t id =  
	let tag =  tag_hash.(int_of_node id) 
	in
	  if tag != Tag.nullt then tag
	  else
	    let tag = tag_id t id in
	    (tag_hash.(int_of_node id) <- tag; tag)
*)
    let is_last t n = equal nil (next_sibling t n)
    
    external prev_text : t -> [`Tree] node -> [`Text ] node = "caml_xml_tree_prev_text" 


    external my_text : t -> [`Tree] node -> [`Text ] node = "caml_xml_tree_my_text"
    external next_text : t -> [`Tree] node -> [`Text ] node = "caml_xml_tree_next_text"
    external doc_ids : t -> [`Tree ] node -> [`Text ] node * [`Text ] node = "caml_xml_tree_doc_ids"
    external text_xml_id : t -> [`Text ] node -> int = "caml_xml_tree_text_xml_id"
    external node_xml_id : t -> [`Tree ] node -> int = "caml_xml_tree_node_xml_id"
    external is_ancestor : t -> [`Tree ] node -> [`Tree ] node -> bool = "caml_xml_tree_is_ancestor"
    external tagged_desc : t -> [`Tree ] node -> Tag.t -> [`Tree ] node = "caml_xml_tree_tagged_desc"
    external tagged_foll : t -> [`Tree ] node -> Tag.t -> [`Tree ] node = "caml_xml_tree_tagged_foll"
    external subtree_tags : t -> [`Tree ] node -> Tag.t -> int = "caml_xml_tree_subtree_tags"
    external tagged_below : t -> [`Tree ] node -> Ptset.int_vector -> Ptset.int_vector -> [`Tree ] node = "caml_xml_tree_tagged_below"
    external tagged_desc_only : t -> [`Tree ] node -> Ptset.int_vector -> [`Tree ] node = "caml_xml_tree_tagged_desc_only"
    external tagged_next : t -> [`Tree ] node -> Ptset.int_vector -> Ptset.int_vector -> [`Tree ] node -> [`Tree ] node = "caml_xml_tree_tagged_next"
    external tagged_foll_only : t -> [`Tree ] node -> Ptset.int_vector -> [`Tree ] node -> [`Tree ] node = "caml_xml_tree_tagged_foll_only"
    external tagged_desc_or_foll_only : t -> [`Tree ] node -> Ptset.int_vector -> [`Tree ] node -> [`Tree ] node = "caml_xml_tree_tagged_foll_only"
    external tagged_foll_below : t -> [`Tree ] node -> Tag.t -> [`Tree ] node -> [`Tree ] node = "caml_xml_tree_tagged_foll_below"

    let test_jump tree tag =
      let rec loop id ctx =
	if id != nil
	then
	  let first = tagged_desc tree id tag
	  and next = tagged_desc tree id tag
	  in
	    loop first id;
	    loop next ctx
      in
	loop (root tree) (root tree)

	  
    let test_xml_tree ppf tags v =
      let pr x = Format.fprintf ppf x in
      let rec aux id = 
	if (is_nil id)
	then ()
	else 
	  begin
	    pr "Node %i, (Tag) %i='%s' (GetTagName), NodeXMLId (Preorder)=%i\n%!" 
	      (int_of_node id)
	      (tag_id v id)
	      (Tag.to_string (tag_id v id))
	      (node_xml_id v id);
	    pr "DocID of PrevText,MyText,NextText : (%i = %s,%i = %s,%i = %s) ParentDoc(my_text)=%i PrevDoc(next_text)=%i\n%!"       
	      (int_of_node (prev_text v id))
	      (Text.get_text v (prev_text v id))
	      (int_of_node (my_text v id))
	      (Text.get_text v (my_text v id))
	      (int_of_node (next_text v id))
	      (Text.get_text v (next_text v id))
	      (int_of_node(parent_doc v (my_text v id)))
	      (int_of_node(prev_doc v (next_text v id)));	      
	    let i1,i2 = doc_ids v id in
	      pr "Testing DocIds below (%i,%i)*\n%!"
		(int_of_node i1) (int_of_node i2);
	      pr "Testing Tagged*\n%!";
	      Ptset.iter (fun t -> 
			    let str = Tag.to_string t in
			    if Tag.pcdata <> t
			    then begin
			      pr "Tag: %s : \n%!" str;
			      pr "TaggedDesc = %i%!, " (tagged_desc v id t);
			      pr "TaggedFoll = %i\n%!" (tagged_foll v id t);
			      pr "SubtreeTags = %i\n%!" (subtree_tags v id t);
			    end) tags;
	      pr "----------------------------\n";	    	    
	    aux(first_child v id);
	    aux(next_sibling v id);
	  end
      in
	aux (root v)
	  
    let rrrr = ref 0

    let time_xml_tree v tag =      

      let rec aux id acc = 
	incr rrrr;
	if (is_nil id)
	then acc
	else begin
	  let acc = 
	    if tag == (tag_id v id)
	    then
	      id::acc
	    else acc
	  in	    
	    aux (next_sibling v id) (aux (first_child v id) acc); 
	end
      in
      let r = aux (root v) [] in
	Printf.eprintf "%i\n%!" !rrrr;r

    let rrrr2 = ref 0
    let time_xml_tree2 v tag =            
      let rec aux id acc ctx= 
	incr rrrr2;
	if (is_nil id)
	then acc
	else begin
	  let acc = 
	    if tag == (tag_id v id)
	    then
	      id::acc
	    else acc
	  in	    
	    aux (tagged_foll_below v id tag ctx) (aux (tagged_desc v id tag) acc id) ctx; 
	end
      in
	let r =  aux (root v) [] (root v) in
	Printf.eprintf "%i\n%!" !rrrr2; r






    let print_skel t =
      let rec aux id = 
	if (is_nil id)
	then Printf.eprintf "#\n"
	else 
	  begin
	    Printf.eprintf "Node %i has tag '%i=%s' DocOrder=%i, DocID of PrevText,MyText,NextText : (%i = %s,%i = %s,%i = %s) parent_doc(my_text)=%i\n%!" 
	      (int_of_node id)
	      (tag_id t id)
	      (Tag.to_string (tag_id t id))
	      (node_xml_id t id)
	      (int_of_node (prev_text t id))
	      (Text.get_text t (prev_text t id))
	      (int_of_node (my_text t id))
	      (Text.get_text t (my_text t id))
	      (int_of_node (next_text t id))
	      (Text.get_text t (next_text t id))
	      (int_of_node(parent_doc t (my_text t id)));
    
	    aux(first_child t id);
	    aux(next_sibling t id);
	  end
      in
	aux (root t)

    let traversal t = 
	let rec aux id =
	  if not (is_nil id)
	  then
	    begin
	      (* ignore (tag t id);
	      ignore (Text.get_text t (prev_text t id));
	      if (is_leaf t id)
		then ignore (Text.get_text t (my_text t id));
	      if (is_last t id)
		then ignore (Text.get_text t (next_text t id)); *)
	      aux (first_child t id);
	      aux (next_sibling t id);
	    end
	in
	  aux (root t)

	    

  end
      
      
  module Binary  = struct

    type node_content = 
	NC of [`Tree ] node 
      | SC of [`Text ] node * [`Tree ] node 
    type string_content = [ `Text ] node
    type descr = 
      | Nil 
      | Node of node_content
      | String of string_content

    type doc = t

    type t = { doc : doc;	       
	       node : descr }
	
    let dump { doc=t } = Tree.print_skel t
    let test_xml_tree ppf tags { doc=t } = Tree.test_xml_tree ppf tags t
    let time_xml_tree { doc=t } tag = Tree.time_xml_tree t tag
    let time_xml_tree2 { doc=t } tag = Tree.time_xml_tree2 t tag
    let test_jump { doc=t } tag = Tree.test_jump t tag
    let contains_array = ref [| |]

    let init_contains t s = 
      let a = Text.contains t.doc s 
      in
	Array.fast_sort (compare) a;
	contains_array := a
	  
    let init_naive_contains t s =
      let i,j = Tree.doc_ids t.doc (Tree.root t.doc)
      in
      let regexp = Str.regexp_string s in
      let matching arg = 
	try
	  let _ = Str.search_forward regexp arg 0;
	  in true
	with _ -> false
      in
      let rec loop n acc l = 
	if n >= j then acc,l
	else
	  let s = (*Printf.eprintf "%i \n%!" n;*)Text.get_cached_text t.doc n
	  in
	    if matching s 
	    then loop (n+1) (n::acc) (l+1) 
	    else loop (n+1) acc l
      in
      let acc,l = loop i [] 0 in
      let a = Array.create l Text.nil in
	let _ = List.fold_left (fun cpt e -> a.(cpt) <- e; (cpt-1)) (l-1) acc
	in
	  contains_array := a
	  


    module DocIdSet = struct
      include Set.Make (struct type t = string_content
			       let compare = (-) end)
			
    end
    let is_node = function { node=Node(_) } -> true | _ -> false
      
    let get_string t (i:string_content) = Text.get_text t.doc i
    open Tree      	       
    let node_of_t t = { doc= t; 
			node = Node(NC (root t)) }


    let parse_xml_uri str = node_of_t       
      (MM((parse_xml_uri str 
	     !Options.sample_factor 
	     !Options.index_empty_texts
	     !Options.disable_text_collection),__LOCATION__))

    let parse_xml_string str = node_of_t 
      (MM((parse_xml_string str
	 !Options.sample_factor 
	 !Options.index_empty_texts 
	 !Options.disable_text_collection),__LOCATION__))


    let save t str = save_tree t.doc str

    let load ?(sample=64) str = node_of_t (load_tree str sample)


    external pool : doc -> Tag.pool = "%identity"
    let tag_pool t = pool t.doc

    let compare a b = match a.node,b.node  with
      | Node(NC i),Node(NC j) -> compare i j
      | _, Node(NC( _ )) -> 1
      | Node(SC (i,_)),Node(SC (j,_)) -> compare i j
      | Node(NC( _ )),Node(SC (_,_)) -> -1
      | _, Node(SC (_,_)) -> 1
      | String i, String j -> compare i j
      | Node _ , String _ -> -1
      | _ , String _ -> 1
      | Nil, Nil -> 0
      | _,Nil -> -1

    let equal a b = (compare a b) == 0

    let string t = match t.node with
      | String i ->  Text.get_text t.doc i
      | _ -> assert false
	  
    let norm (n : [`Tree ] node ) =  if is_nil n then Nil else Node (NC n)
	
    let descr t = t.node

    let nts = function
	Nil -> "Nil"
      | String i -> Printf.sprintf "String %i" i
      | Node (NC t) -> Printf.sprintf "Node (NC %i)"  (int_of_node t)
      | Node (SC (t,i)) -> Printf.sprintf "Node (SC (%i,%i))"  (int_of_node t) (int_of_node i)

    let mk_nil t = { t with node = Nil }		  
    let root n = { n with node = norm (Tree.root n.doc) }
    let is_root n = match n.node with
      | Node(NC t) -> (int_of_node t) == 0 
      | _ -> false

    let parent n =  
      if is_root n then { n with node=Nil}
      else
      let node' =
	match n.node with
	  |  Node(NC t) -> 
	       let txt = prev_text n.doc t in
		 if Text.is_empty n.doc txt then
		   let ps = Tree.prev_sibling n.doc t in
		     if is_nil ps
		     then
		       Node(NC (Tree.parent n.doc t))
		     else Node(NC ps)
		 else
		   Node(SC (txt,t))
	  | Node(SC(i,t)) ->
	      let ps = Tree.prev_sibling n.doc t in
		if is_nil ps
		then Node (NC(parent_doc n.doc i))
		else Node(NC ps)
	  | _ -> failwith "parent"
      in
	{ n with node = node' }

    let first_child n = 
      let node' = 
	match n.node with
	  | Node (NC t) when is_leaf n.doc t ->
	      let txt = my_text n.doc t in
		if Text.is_empty n.doc txt
		then Nil
		else Node(SC (txt,Tree.nil))
	  | Node (NC t) -> 
	      let fs = first_child n.doc t in
	      let txt = prev_text n.doc fs in
		if Text.is_empty n.doc txt
		then norm fs
		else Node (SC (txt, fs))		  
	  | Node(SC (i,_)) -> String i
	  | Nil | String _ -> failwith "first_child"
      in
	{ n with node = node'}
	  
    let next_sibling n = 
      let node' =
	match n.node with
	  | Node (SC (_,ns)) -> norm ns
	  | Node(NC t) ->
	      let ns = next_sibling n.doc t in
	      let txt = next_text n.doc t in
		if Text.is_empty n.doc txt
		then norm ns
		else Node (SC (txt, ns))
	  | Nil | String _  -> failwith "next_sibling"
      in
	{ n with node = node'}
	  
	  
    let left = first_child 
    let right = next_sibling
    
    let id = 
      function  { doc=d; node=Node(NC n)}  -> node_xml_id d n
	| { doc=d;  node=Node(SC (i,_) )} -> text_xml_id d i
	| _ ->  -1 (*
	    Format.fprintf Format.err_formatter "Failure id on %s\n%!" (nts x.node);
	    failwith "id" *)
	    
    let tag = 
      function { node=Node(SC _) } -> Tag.pcdata
	| { doc=d; node=Node(NC n)} -> tag_id d n
	| _ -> failwith "tag"
    
    let string_below t id =
      let strid = parent_doc t.doc id in
	match t.node with
	  | Node(NC(i)) -> 
	      (Tree.equal i strid) || (is_ancestor t.doc i strid)
	  | Node(SC(i,_)) -> Text.equal i id
	  | _ -> false


    let tagged_foll t tag =
      if tag = Tag.attribute || tag = Tag.pcdata then failwith "tagged_foll"
      else match t with
	| { doc=d; node=Node(NC n) } -> { t with node = norm (tagged_foll d n tag) }
	| { doc=d; node=Node(SC (_,n)) } when is_nil n -> { t with node= Nil } 
	| { doc=d; node=Node(SC (_,n)) } ->
	    let nnode = 
	      if tag_id d n == tag then n
	      else 
		let n' = tagged_desc d n tag in
		  if is_nil n' then tagged_foll d n tag
		  else n'
	    in {t with node= norm nnode}
	| _ -> { t with node=Nil }
	    

    let tagged_desc t tag =
      if tag = Tag.attribute || tag = Tag.pcdata then failwith "tagged_desc"
      else match t with
	| { doc=d; node=Node(NC n) } -> { t with node = norm (tagged_desc d n tag) }
	| _ -> { t with node=Nil }

	    
    let tagged_next t tb tf s = 
      match s  with
	| { node = Node (NC(below)) } -> begin
	    match t with
	      | { doc = d; node=Node(NC n) } ->
		  { t with node= norm (tagged_next d n (Ptset.to_int_vector tb) (Ptset.to_int_vector tf) below) }
	      | { doc = d; node=Node(SC (i,n) ) } when is_nil n ->
		  let p = parent_doc d i in
		    { t with node= norm (tagged_next d p (Ptset.to_int_vector tb) (Ptset.to_int_vector tf) below) }
	      | { doc = d; node=Node(SC (_,n) ) } ->
		  if Ptset.mem (tag_id d n) (Ptset.union tb tf)
		  then { t with node=Node(NC(n)) }
		  else
		    let vb = Ptset.to_int_vector tb in
		    let vf = Ptset.to_int_vector tf in
		    let node = 
		      let dsc = tagged_below d n vb vf in
			if is_nil dsc
			then tagged_next d n vb vf below
			else dsc
		    in
		      { t with node = norm node }
	      | _ -> {t with node=Nil }
	  end
	    
	| _ -> {t with node=Nil }

    let tagged_foll_only t tf s = 
      match s  with
	| { node = Node (NC(below)) } -> begin
	    match t with
	      | { doc = d; node=Node(NC n) } ->
		  { t with node= norm (tagged_foll_only d n (Ptset.to_int_vector tf) below) }
	      | { doc = d; node=Node(SC (i,n) ) } when is_nil n ->
		  let p = parent_doc d i in
		    { t with node= norm (tagged_foll_only d p  (Ptset.to_int_vector tf) below) }
	      | { doc = d; node=Node(SC (_,n) ) } ->
		  if Ptset.mem (tag_id d n) tf
		  then { t with node=Node(NC(n)) }
		  else
		    let vf = Ptset.to_int_vector tf in
		    let node = 
		      let dsc = tagged_desc_only d n vf in
			if is_nil dsc
			then tagged_foll_only d n vf below
			else dsc
		    in
		      { t with node = norm node }
	      | _ -> {t with node=Nil }
	  end
	    
	| _ -> {t with node=Nil }
	  

    let tagged_below t tc td =
      match t with
	| { doc = d; node=Node(NC n) } -> 
	    let vc = Ptset.to_int_vector tc
	    in
	    let vd = Ptset.to_int_vector td
	    in
	      { t with node= norm(tagged_below d n vc vd) }
	| _ -> { t with node=Nil }

    let tagged_desc_only t td =
      match t with
	| { doc = d; node=Node(NC n) } -> 
	    let vd = Ptset.to_int_vector td
	    in
	      { t with node= norm(tagged_desc_only d n vd) }
	| _ -> { t with node=Nil }

	
    let last_idx = ref 0
    let array_find a i j =
      let l = Array.length a in
      let rec loop idx x y =
	if x > y || idx >= l then Text.nil
	else
	  if a.(idx) >= x then if a.(idx) > y then Text.nil else (last_idx := idx;a.(idx))
	  else loop (idx+1) x y
      in
	if a.(0) > j || a.(l-1) < i then Text.nil
	else loop !last_idx i j 
	  
	
    let text_below t = 
      let l = Array.length !contains_array in
	if l = 0 then { t with node=Nil }
	else
	  match t with
	    | { doc = d; node=Node(NC n) } ->
		let i,j = doc_ids t.doc n in
		let id = array_find !contains_array i j
		in
		  if id == Text.nil then  
		    { t with  node=Nil }
		  else
		    {t with  node = Node(SC(id, Tree.next_sibling d (Tree.prev_doc d id))) }
	    | _ -> { t with node=Nil }

    let text_next t root =
      let l = Array.length !contains_array in
	if l = 0 then { t with node=Nil }
	else
	  let inf = match t with
	    | { doc =d; node = Node(NC n) } -> snd(doc_ids d n)+1
	    | { node = Node(SC(i,_)) } -> i+1
	    | _ -> assert false
	  in
	    match root with
	      | { doc = d; node= Node (NC n) } ->
		  let _,j = doc_ids t.doc n in
		    
		  let id = array_find !contains_array inf j
		  in
		    if id == Text.nil then  { doc = d; node= Nil }
		    else
		      {doc = d; node = Node(SC(id,Tree.next_sibling d (Tree.prev_doc d id))) }
	      | _ -> { t with node=Nil}
		  


    let subtree_tags t tag =
      match t with 
	  { doc = d; node = Node(NC n) } -> 
	    subtree_tags d n tag
	| _ -> 0

    let tagged_desc_array = ref [| |]
    let idx = ref 0

    let init_tagged_next t tagid =
      let l = subtree_tags (root t) tagid
      in
	tagged_desc_array := Array.create l { t with node= Nil };
	let i = ref 0 in
	  let rec collect t =
	    if is_node t then begin
	      if tag t == tagid then
		begin
		  !tagged_desc_array.(!i) <- t;
		  incr i;
		end;
	      collect (first_child t);
	      collect (next_sibling t)
	    end;
	  in
	    collect t;
	    idx := 0

    let print_id ppf v = 
      let pr x= Format.fprintf ppf x in
	match v with
	    { node=Nil } -> pr "NULLT: -1"
	  | { node=String(i) } | { node=Node(SC(i,_)) } -> pr "DocID: %i" (int_of_node i)
	  | { node=Node(NC(i)) } -> pr "Node: %i" (int_of_node i)
	      
	      
	  
(*    let tagged_next t tag = 
      if !idx >= Array.length !tagged_desc_array 
      then {t with node=Nil}
      else
	let r = !tagged_desc_array.(!idx) 
	in
	  incr idx; r
*)		  


    let has_tagged_foll t tag = is_node (tagged_foll t tag)
    let has_tagged_desc t tag = is_node (tagged_desc t tag)

    let contains t s = 
      Array.fold_left (fun a i -> DocIdSet.add i a) DocIdSet.empty (Text.contains t.doc s)


    let contains_old t s = 
      let regexp = Str.regexp_string s in
      let matching arg = 
	try
	  let _ = Str.search_forward regexp arg 0;
	  in true
	with _ -> false
      in
      let rec find t acc = match t.node with
	| Nil -> acc
	| String i ->
	    if  matching (string t) then DocIdSet.add i acc else acc
	| Node(_) ->  (find (left t )) ((find (right t))  acc)
      in
	find t DocIdSet.empty


    let contains_iter t s = 
      let regexp = Str.regexp_string s in
      let matching arg = 
	try
	  let _ = Str.search_forward regexp arg 0;
	  in true
	with _ -> false
      in
      let size = Text.size t.doc in
      let rec find acc n = 
	if n == size then acc
	else
	  find 
	    (if matching (Text.get_cached_text t.doc (Obj.magic n)) then 
	     DocIdSet.add (Obj.magic n) acc
	   else acc) (n+1)
      in
	find DocIdSet.empty 0




    let count_contains t s =   Text.count_contains t.doc s
    let count t s =   Text.count t.doc s

    let is_left t =
      if is_root t then false
      else
      if tag (parent t) == Tag.pcdata then false
      else
	let u = left (parent t) in
	  (id t) == (id u)

    let print_xml_fast outc t =
      let rec loop ?(print_right=true) t = match t.node with 
	| Nil -> ()
	| String (s) -> output_string outc (Text.get_text t.doc s)
	| Node _ when Tag.equal (tag t) Tag.pcdata -> 
	    loop (left t); 
	    if print_right then loop (right t)
	    
	| Node (_) -> 
	    let tg = Tag.to_string (tag t) in
	    let l = left t 
	    and r = right t 
	    in
	      output_char outc  '<';
	      output_string outc  tg;
	      ( match l.node with
		    Nil -> output_string outc  "/>"
		  | String _ -> assert false
		  | Node(_) when Tag.equal (tag l) Tag.attribute -> 
		      (loop_attributes (left l);
		       match (right l).node with
			 | Nil -> output_string outc  "/>"
			 | _ -> 
			     output_char outc  '>'; 
			     loop (right l);
			     output_string outc  "</";
			     output_string outc  tg;
			     output_char outc '>' )
		  | _ ->
		      output_char outc  '>'; 
		      loop l;
		      output_string outc "</";
		      output_string outc tg;
		      output_char outc '>'
	      );if print_right then loop r
      and loop_attributes a =

	match a.node with 
	  | Node(_) ->
	      let value =
		match (left a).node with
		  | Nil -> ""
		  | _ -> string (left(left a)) 
	      in
	 	output_char outc ' ';
		output_string outc (Tag.to_string (tag a));
		output_string outc "=\"";
		output_string outc value;
		output_char outc '"';
		loop_attributes (right a)
	| _ -> ()
      in
	loop ~print_right:false t


    let print_xml_fast outc t = 
      if Tag.to_string (tag t) = "" then
	print_xml_fast outc (first_child t)
      else print_xml_fast outc t
	




    let traversal t = Tree.traversal t.doc
    let full_traversal t = 
      let rec aux n =
	match n.node with
	| Nil -> ()
	| String i -> () (*ignore(Text.get_text t.doc i)  *)
	| Node(_) -> 
	    (* tag_id n; *)
	    aux (first_child n);
	    aux (next_sibling n)
      in aux t

    let print_stats _ = ()
  end

end



IFDEF DEBUG
THEN
module DEBUGTREE 
  = struct
    
    let _timings = Hashtbl.create 107
    

    let time _ref f arg = 
      let t1 = Unix.gettimeofday () in
      let r = f arg in
      let t2 = Unix.gettimeofday () in 
      let t = (1000. *.(t2 -. t1)) in

      let (time,count) = try 
	Hashtbl.find _timings _ref
      with
	| Not_found -> 0.,0
      in
      let time = time+. t 
      and count = count + 1
      in
	Hashtbl.replace _timings _ref (time,count);r

    include XML.Binary


    let first_child_ doc node = 
     time ("XMLTree.FirstChild()") (XML.Tree.first_child doc)  node
    let next_sibling_ doc node = 
      time ("XMLTree.NextSibling()") (XML.Tree.next_sibling doc) node

    let is_empty_ text node = 
      time ("TextCollection.IsEmpty()") (XML.Text.is_empty text) node

    let prev_text_ doc node = 
      time ("XMLTree.PrevText()") (XML.Tree.prev_text doc) node

    let my_text_ doc node = 
      time ("XMLTree.MyText()") (XML.Tree.my_text doc) node
	
    let next_text_ doc node = 
      time ("XMLTree.NextText()") (XML.Tree.next_text doc) node

    let is_leaf_ doc node =  
      time ("XMLTree.IsLeaf()") (XML.Tree.is_leaf doc ) node
	
    let node_xml_id_ doc node =  
      time ("XMLTree.NodeXMLId()") (XML.Tree.node_xml_id doc ) node
	
    let text_xml_id_ doc node =  
      time ("XMLTree.TextXMLId()") (XML.Tree.text_xml_id doc ) node


    let first_child n =
      let node' =
    	match n.node with
    	  | Node (NC t) when is_leaf_ n.doc t ->
    	      let txt = my_text_ n.doc t in
    		if is_empty_ n.doc txt
    		then Nil
    		else Node(SC (txt,XML.Tree.nil))
    	  | Node (NC t) ->
    	      let fs = first_child_ n.doc t in
    	      let txt = prev_text_ n.doc fs in
    		if is_empty_ n.doc txt
    		then norm fs
    		else Node (SC (txt, fs))
    	  | Node(SC (i,_)) -> String i
    	  | Nil | String _ -> failwith "first_child"
      in
    	{ n with node = node'}

	  
    let next_sibling n =
      let node' =
    	match n.node with
    	  | Node (SC (_,ns)) -> norm ns
    	  | Node(NC t) ->
    	      let ns = next_sibling_ n.doc t in
    	      let txt = 
		if XML.Tree.is_nil ns then
		  next_text_ n.doc t 
		else prev_text_ n.doc ns
	      in
    		if is_empty_ n.doc txt
    		then norm ns
    		else Node (SC (txt, ns))
    	  | Nil | String _  -> failwith "next_sibling"
      in
    	{ n with node = node'}

    let id = 
      function  { doc=d; node=Node(NC n)}  -> node_xml_id_ d n
	| { doc=d;  node=Node(SC (i,_) )} -> text_xml_id_ d i
	| _ -> failwith "id"
	    
    (* Wrapper around critical function *)
    let string t = time ("TextCollection.GetText()") (string) t
    let left = first_child
    let right = next_sibling
    let tag t =  time ("XMLTree.GetTag()") (tag) t
      
    let print_stats ppf = 
      let total_time,total_calls =
	Hashtbl.fold  (fun _ (t,c) (tacc,cacc) ->
			 tacc+. t, cacc + c)  _timings (0.,0)

      in
	Format.fprintf ppf
	  "Timing : Function Name, number of calls,%% of total calls, mean time, total time, %% of total time\n%!";
	Hashtbl.iter (fun name (time,count) ->
			Format.fprintf ppf  "%-27s% 8d\t% 4.2f%%\t% 4.6f ms\t% 4.6f ms\t%04.2f%%\n%!"
			  name 
			  count 
			  (100. *. (float_of_int count)/.(float_of_int total_calls))
			  (time /. (float_of_int count))
			  time
			  (100. *. time /.  total_time)) _timings;
	Format.fprintf ppf  "-------------------------------------------------------------------\n";
	Format.fprintf ppf "%-27s% 8d\t% 4.0f%%\t########## ms\t% 4.6f ms\t% 4.0f%%\n%!"
	  "Total" total_calls 100. total_time 100.
			  

    let print_xml_fast outc t =
      let rec loop ?(print_right=true) t = match t.node with 
	| Nil -> ()
	| String (s) -> output_string outc (string t)
	| Node _ when Tag.equal (tag t) Tag.pcdata -> loop (left t); loop (right t)
	    
	| Node (_) -> 
	    let tg = Tag.to_string (tag t) in
	    let l = left t 
	    and r = right t 
	    in
	      output_char outc  '<';
	      output_string outc  tg;
	      ( match l.node with
		    Nil -> output_string outc  "/>"
		  | String _ -> assert false
		  | Node(_) when Tag.equal (tag l) Tag.attribute -> 
		      (loop_attributes (left l);
		       match (right l).node with
			 | Nil -> output_string outc  "/>"
			 | _ -> 
			     output_char outc  '>'; 
			     loop (right l);
			     output_string outc  "</";
			     output_string outc  tg;
			     output_char outc '>' )
		  | _ ->
		      output_char outc  '>'; 
		      loop l;
		      output_string outc "</";
		      output_string outc tg;
		      output_char outc '>'
	      );if print_right then loop r
      and loop_attributes a =

	match a.node with 
	  | Node(_) ->
	      let value =
		match (left a).node with
		  | Nil -> ""
		  | _ -> string (left(left a)) 
	      in
	 	output_char outc ' ';
		output_string outc (Tag.to_string (tag a));
		output_string outc "=\"";
		output_string outc value;
		output_char outc '"';
		loop_attributes (right a)
	| _ -> ()
      in
	loop ~print_right:false t


    let print_xml_fast outc t = 
      if Tag.to_string (tag t) = "" then
	print_xml_fast outc (first_child t)
      else print_xml_fast outc t

	


end

module Binary = DEBUGTREE
ELSE
module Binary = XML.Binary
END (* IFDEF DEBUG *)