(* Copyright (C) 2000-2002, HELM Team.
 * 
 * This file is part of HELM, an Hypertextual, Electronic
 * Library of Mathematics, developed at the Computer Science
 * Department, University of Bologna, Italy.
 * 
 * HELM 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.
 * 
 * HELM 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 HELM; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA  02111-1307, USA.
 * 
 * For details, see the HELM World-Wide-Web page,
 * http://cs.unibo.it/helm/.
 *)

let update_dom ~(from : Gdome.document) (d : Gdome.document) =
 let rec aux (p: Gdome.node) (f: Gdome.node) (t: Gdome.node) =
(* Perche' non andava?
  if f#get_localName = t#get_localName &&
     f#get_namespaceURI = t#get_namespaceURI
*)
  match
   f#get_nodeType,t#get_nodeType,
   f#get_namespaceURI,t#get_namespaceURI,
   f#get_localName,t#get_localName
  with
     GdomeNodeTypeT.TEXT_NODE,GdomeNodeTypeT.TEXT_NODE,_,_,_,_ when
      match f#get_nodeValue, t#get_nodeValue with
         Some v, Some v' -> v#to_string = v'#to_string
       | _,_ -> assert false
      ->
prerr_endline ("XML_DIFF: preservo il nodo testo " ^ match f#get_nodeValue with Some v -> v#to_string | None -> assert false);
       ()
   | GdomeNodeTypeT.ELEMENT_NODE,GdomeNodeTypeT.ELEMENT_NODE,
      Some nu, Some nu', Some ln, Some ln' when
       ln#to_string = ln'#to_string && nu#to_string = nu'#to_string ->
prerr_endline ("XML_DIFF: preservo il nodo "^ nu#to_string ^ ":" ^ln#to_string);
        begin
         match f#get_attributes, t#get_attributes with
            Some fattrs, Some tattrs ->
             let flen = fattrs#get_length in
             let tlen = tattrs#get_length in
              let processed = ref [] in
              for i = 0 to flen -1 do
               match fattrs#item i with
                  None -> assert false
                | Some attr ->
                    match attr#get_namespaceURI with
                       None ->
                        (* Back to DOM Level 1 ;-( *)
                        begin
                         let name = attr#get_nodeName in
                          match tattrs#getNamedItem ~name with
                             None ->
prerr_endline ("XML_DIFF: rimuovo l'attributo " ^ name#to_string);
                              ignore (f#removeChild attr)
                           | Some attr' ->
                              processed :=
                               (None,Some name)::!processed ;
                              match attr#get_nodeValue, attr'#get_nodeValue with
                                 Some v1, Some v2 when
                                     v1#to_string = v2#to_string
                                  || (name#to_string = "selection" &&
                                      nu#to_string =
                                       "http://www.w3.org/1998/Math/MathML" &&
                                      ln#to_string = "maction")
                                  ->
prerr_endline ("XML_DIFF: DOM 1; preservo l'attributo " ^ name#to_string);
                                   ()
                               | Some _, Some _ ->
prerr_endline ("XML_DIFF: DOM 1; rimpiazzo l'attributo " ^ name#to_string);
                                  let attr'' = from#importNode attr' true in
                                   ignore (fattrs#setNamedItem attr'')
                               | _,_ -> assert false
                        end
                     | Some namespaceURI ->
                        let localName = 
                         match attr#get_localName with
                           Some v -> v
                          | None -> assert false
                        in
                         match
                          tattrs#getNamedItemNS ~namespaceURI ~localName
                         with
                            None ->
prerr_endline ("XML_DIFF: rimuovo l'attributo " ^ localName#to_string);
                             ignore (f#removeChild attr)
                          | Some attr' ->
                             processed :=
                              (Some namespaceURI,Some localName)::!processed ;
                             (*CSC: questo mi dice read-only ;-( 
                               attr#set_nodeValue attr'#get_nodeValue *)
                             (*CSC: questo mi abortisce con una assert
                             let attr'' = from#importNode attr' true in
                              ignore(f#replaceChild ~newChild:attr'' ~oldChild:attr)*)
                              match attr#get_nodeValue, attr'#get_nodeValue with
                                 Some v1, Some v2 when
                                  v1#to_string = v2#to_string ->
prerr_endline ("XML_DIFF: DOM 2; preservo l'attributo " ^ namespaceURI#to_string ^ ":" ^ localName#to_string);
                                   ()
                               | Some _, Some _ ->
prerr_endline ("XML_DIFF: DOM 2; rimpiazzo l'attributo " ^ namespaceURI#to_string ^ ":" ^ localName#to_string);
                                  let attr'' = from#importNode attr' true in
                                   ignore (fattrs#setNamedItem attr'')
                               | _,_ -> assert false
              done ;
              for i = 0 to tlen -1 do
               match tattrs#item i with
                  None -> assert false
                | Some attr ->
let debugs = ref "" in
                   let namespaceURI,localName =
                    match attr#get_namespaceURI with
                       None ->
debugs := ("XML_DIFF: DOM 1.0; creo un nuovo attributo " ^ attr#get_nodeName#to_string) ;
                        None,attr#get_nodeName
                     | Some namespaceURI as v ->
debugs := ("XML_DIFF: DOM 2.0; creo un nuovo attributo " ^ namespaceURI#to_string ^ ":" ^ match attr#get_localName with Some v -> v#to_string | None -> assert false);
                       v, match attr#get_localName with
                          None -> assert false
                        | Some v -> v
                   in
                    if
                     not
                      (List.exists
                        (function
                            None,Some localName' ->
                             (match namespaceURI with
                                 None ->
                                  localName#to_string = localName'#to_string
                               | Some _ -> false)
                          | Some namespaceURI', Some localName' ->
                             (match namespaceURI with
                                 None -> false
                               | Some namespaceURI ->
                                  localName#to_string = localName'#to_string &&
                                  namespaceURI#to_string=namespaceURI'#to_string
                             )
                          | _,_ -> assert false
                        ) !processed)
                    then
                     let attr' = from#importNode attr false in
prerr_endline !debugs ;
                      ignore (fattrs#setNamedItem attr')
              done
          | _,_ -> assert false
        end ;
        let fchildren = f#get_childNodes in
        let tchildren = t#get_childNodes in
         let rec dumb_diff =
          function
             [],[] -> ()
           | he1::tl1,he2::tl2 ->
prerr_endline "XML_DIFF: processo una coppia di figli" ;
              aux f he1 he2 ;
              dumb_diff (tl1,tl2)
           | [],tl2 ->
prerr_endline "XML_DIFF: appendo i nodi residui" ;
              List.iter
               (function n ->
                 let n' = from#importNode n true in
                  ignore (f#appendChild n')
               ) tl2
           | tl1,[] ->
prerr_endline "XML_DIFF: cancello i nodi residui" ;
              List.iter (function n -> ignore (f#removeChild n)) tl1
         in
          let node_list_of_nodeList nl =
           let rec aux i =
            match nl#item ~index:i with
               None -> []
             | Some n when
                   n#get_nodeType = GdomeNodeTypeT.ELEMENT_NODE
                or n#get_nodeType = GdomeNodeTypeT.TEXT_NODE ->
                 n::(aux (i+1))
             | Some n ->
prerr_endline ("XML_DIFF: mi sto perdendo i nodi di tipo " ^ string_of_int (Obj.magic n#get_nodeType)) ;
               aux (i+1)
           in
            aux 0
          in
for i = 0 to fchildren#get_length - 1 do
match fchildren#item i with
None -> prerr_endline "EUREKA: ma siamo matti?"
|Some n ->
match n#get_nodeType with GdomeNodeTypeT.ATTRIBUTE_NODE -> prerr_endline "EUREKA attr" | GdomeNodeTypeT.CDATA_SECTION_NODE -> prerr_endline "EUREKA text" | GdomeNodeTypeT.DOCUMENT_FRAGMENT_NODE -> prerr_endline "EUREKA document fragment" | _ -> prerr_endline ("EUREKA " ^ string_of_int (Obj.magic n#get_nodeType))
done ;
prerr_endline("XML_DIFF: from ha " ^ string_of_int fchildren#get_length ^ " nodi, ovvero " ^ string_of_int (List.length (node_list_of_nodeList fchildren)) ^ " figli");
prerr_endline("XML_DIFF: to   ha " ^ string_of_int tchildren#get_length ^ " nodi, ovvero " ^ string_of_int (List.length (node_list_of_nodeList tchildren)) ^ " figli");
           dumb_diff
            (node_list_of_nodeList fchildren, node_list_of_nodeList tchildren)
   | t1,t2,_,_,_,_ when
      (t1 = GdomeNodeTypeT.ELEMENT_NODE || t1 = GdomeNodeTypeT.TEXT_NODE) &&
      (t2 = GdomeNodeTypeT.ELEMENT_NODE || t2 = GdomeNodeTypeT.TEXT_NODE) ->
       let t' = from#importNode t true in
prerr_endline "XML_DIFF: importo il nodo" ;
(*
prerr_endline ("Rimpiazzo" ^ (match f#get_namespaceURI with Some s -> s#to_string) ^ ":" ^ (match f#get_localName with Some s -> s#to_string) ^ " con " ^ (match t#get_namespaceURI with Some s -> s#to_string) ^ ":" ^ (match t#get_localName with Some s -> s#to_string) ^ " in " ^ (match p#get_localName with Some s -> s#to_string | None -> "_")) ;
*)
        ignore (p#replaceChild ~newChild:t' ~oldChild:f)
   | _,_,_,_,_,_ -> assert false
 in
  try
   aux (d :> Gdome.node)
    (from#get_documentElement :> Gdome.node)
    (d#get_documentElement :> Gdome.node)
  with
     (GdomeInit.DOMException (e,msg) as ex) ->
(*
    let module E = GdomeDOMExceptionT in
*)
       prerr_endline
        ("DOM EXCEPTION: " ^ msg ^ " --- " ^
string_of_int (Obj.magic e)) ;
       raise ex
 (*
        match e with
           E.NO_ERR -> "NO_ERR"
         | E.INDEX_SIZE_ERR -> "INDEX_SIZE_ERR"
         | E.DOMSTRING_SIZE_ERR -> "DOMSTRING_SIZE_ERR"
         | E.HIERARCHY_REQUEST_ERR -> "HIERARCHY_REQUEST_ERR"
         | E.WRONG_DOCUMENT_ERR -> "WRONG_DOCUMENT_ERR"
         | E.INVALID_CHARACTER_ERR -> "INVALID_CHARACTER_ERR"
         | E.NO_DATA_ALLOWED_ERR -> "NO_DATA_ALLOWER_ERR"
         | E.NO_MODIFICATION_ALLOWED_ERR -> "NO_MODIFICATION_ALLOWED_ERR"
         | E.NOT_FOUND_ERR -> "NOT_FOUND_ERR"
         | E.NOT_SUPPORTED_ERR -> "NOT_SUPPORTED_ERR"
         | E.INUSE_ATTRIBUTE_ERR -> "INUSE_ATTRIBUTE_ERR"
         | E.INVALID_STATE_ERR -> "INVALID_STATE_ERR"
         | E.SYNTAX_ERR -> "SYNTAX_ERR"
         | E.INVALID_MODIFICATION_ERR -> "INVALID_MODIFICATION_ERR"
         | E.NAMESPACE_ERR -> "NAMESPACE_ERR"
         | E.INVALID_ACCESS_ERR -> "INVALID_ACCESS_ERR"
*)
  | e ->
    prerr_endline "PROBLEMA" ;
    raise e
;;