(******************************************************************************)
(*  SXSI : XPath evaluator                                                    *)
(*  Kim Nguyen (Kim.Nguyen@nicta.com.au)                                      *)
(*  Copyright NICTA 2008                                                      *)
(*  Distributed under the terms of the LGPL (see LICENCE)                     *)
(******************************************************************************)

open Ata

let l = ref [] ;;
let time f x =
  let t1 = Unix.gettimeofday () in
  let r = f x in
  let t2 = Unix.gettimeofday () in 
  let t = (1000. *. (t2 -. t1)) in
    l:= t::!l;
    Printf.eprintf "  %fms\n%!" t ;
    r
;;
let total_time () =  List.fold_left (+.) 0. !l;;
let enabled_gc = Gc.get()
let disabled_gc = { Gc.get() with
		      Gc.max_overhead = 1000000; 
		      Gc.space_overhead = 100 }

let main v query_string output =
    let _ = Tag.init (Tree.tag_pool v) in
      Printf.eprintf "Parsing query : ";    
      let query = try
	time
	  XPath.Parser.parse_string query_string
      with
	  Ulexer.Loc.Exc_located ((x,y),e) -> Printf.eprintf "character %i-%i %s\n" x y (Printexc.to_string e);exit 1
      in
	XPath.Ast.print Format.err_formatter query;
	Format.fprintf Format.err_formatter "\n%!";
	Printf.eprintf "Compiling query : ";
	let auto,ltags,contains = time (XPath.Compile.compile ~querystring:query_string) query in 
	let _ = Ata.dump Format.err_formatter auto in
	let _ = Printf.eprintf "%!" in
	let jump_to =
	  match contains with
	      None -> (max_int,`NOTHING)
	    | Some s -> 
		let r = Tree.count v s 
		in
		  Printf.eprintf "%i documents in the TextCollection\n" (Tree.text_size v);
		  Printf.eprintf "Global count is %i, using " r;
		  if r < !Options.tc_threshold then begin		  
		    Printf.eprintf "TextCollection contains\nCalling global contains : ";
		    time (Tree.init_contains v) s;
		  end
		  else begin
		    Printf.eprintf "Naive contains\nCalling global contains : ";
		    time (Tree.init_naive_contains v) s
		  end;(r,`CONTAINS(s))
	in
	let test_list = 
	  if (!Options.backward) then begin
	    Printf.eprintf "Finding min occurences : ";
	    time 
	      ( List.fold_left (fun ((min_occ,kind)as acc)  (tag,_) ->
			      let numtags = Tree.subtree_tags v tag in
				if  ((numtags < min_occ) && numtags >= 2)
				then (numtags,`TAG(tag))
				else acc) jump_to) ltags
	  end
	  else (max_int,`NOTHING)
	in
	let _ = if (snd test_list) != `NOTHING then
	  let occ,s1,s2 = match test_list with
	    | (x,`TAG (tag)) -> (x, "tag", (Tag.to_string tag))
	    | (x,`CONTAINS(s)) -> (x, "contains()", s)
	    | _ -> assert false
	  in
	    Printf.eprintf "Will jump to %s %s occuring %i time\n%!" s1 s2 occ
	in
	  Printf.eprintf "Execution time %s : "
	    (if !Options.count_only then "(counting only)" else if !Options.backward then "(bottomup)" else "");
	  begin
	    let _ = Gc.full_major();Gc.compact() in
	      (*	    let _ = Gc.set (disabled_gc) in  *)
	      if !Options.backward && ((snd test_list) != `NOTHING )then 
		
		let r = time (bottom_up_count auto v )(snd test_list)  in
		let _ = Printf.eprintf "Number of nodes in the result set : %i\n%!" r 
		in ()
	      else
		let _ = 
		  if !Options.backward then Printf.eprintf "WARNING: couldn't find a jumping point, running top-down\n" 
		in
		if !Options.count_only then
		  let r = time ( top_down_count auto ) v in 
		  let _ = Printf.eprintf "Number of nodes in the result set : %i\n%!" r
		  in ()
		else      
		  let result = time (top_down auto) v in	  
		  let rcount = IdSet.length result in
	      	    Printf.eprintf "Number of nodes in the result set : %i\n" rcount;
		    Printf.eprintf "\n%!";
		    begin
 		      match output with
			| None -> ()
			| Some f ->		      
			    Printf.eprintf "Serializing results : ";
			    time( fun () ->
				    let oc = open_out f in
				      output_string oc "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n";				
				      IdSet.iter (fun t -> 
						    Tree.print_xml_fast oc t;
						    output_char oc '\n';
						    output_string oc "----------\n";
						 ) result) ();
		    end;
	  end;
	  let _ = Gc.set enabled_gc in
	    Printf.eprintf "Total running time : %fms\n%!" (total_time())
;;

Options.parse_cmdline();;

let v = 
  if (Filename.check_suffix !Options.input_file ".srx")
  then 
    begin
      Printf.eprintf "Loading from file : ";
      time (Tree.load  ~sample:!Options.sample_factor )
    (Filename.chop_suffix !Options.input_file ".srx");
	end
  else 
    let v = 
      time (fun () -> let v = Tree.parse_xml_uri !Options.input_file;
	    in Printf.eprintf "Parsing document : %!";v
	   ) () 
    in
      if !Options.save_file <> ""
      then begin
	Printf.eprintf "Writing file to disk : ";
	time (Tree.save v) !Options.save_file;
      end;
      v
in
  main v !Options.query !Options.output_file;;