open Printf

let pp_error title msg =
  sprintf "<div><b class='error'>%s:</b> %s</div><br />" title msg

let paginate ~size ~page l =
  let min = 1 + (page-1) * size in
  let max = page * size in
  let rec aux i l =
    match (i, l) with
    | _, [] -> []
    | i, hd :: tl when i < min -> aux (i+1) tl
    | i, hd :: tl when i >= min && i <= max -> hd :: aux (i+1) tl
    | i, hd :: tl -> []
  in
  assert (size > 0 && page > 0);
  aux 1 l

  (** pretty print a list of URIs to an HELM theory file *)
let theory_of_result page result =
  let results_per_page =
    Helm_registry.get_int "search_engine.results_per_page"
  in
  let results_no = List.length result in
  let buffer = Buffer.create (200 * results_no) in
  let result = paginate ~size:results_per_page ~page result in
  if results_no > 0 then
   let mode = "typeonly" in
   let output_results () =
    let idx = ref ((page - 1) * results_per_page + 1) in
     List.iter
      (fun uri ->
        incr idx;
        Printf.bprintf buffer 
           "<tr>
            <td valign=\"top\">%d.</td>
            <td><span class=\"uri\">%s</span></td>
            </tr>
            <tr>
            <td />
            <td><ht:OBJECT uri=\"%s\" mode=\"%s\"/></td>
            </tr>"
          !idx uri uri mode) result ;
   in
   let summary =
     sprintf "<b>%d</b> result%s found"
       results_no (if results_no > 1 then "s" else "")
   in
    begin
     Buffer.add_string buffer
      "<table xmlns:ht=\"http://www.cs.unibo.it/helm/namespaces/helm-theory\">";
     output_results ();
     Buffer.add_string buffer "</table>";
     (summary, Buffer.contents buffer)
    end
  else
    ("no results found", "")

let html_of_interpretations interps =
  let choice_of_interp interp =
    sprintf "<table>\n%s\n</table>"
      (String.concat "\n"
        (List.map
           (fun (k, v) ->
              sprintf "<tr><td><em>%s</em></td><td>%s</td></tr>" k v)
           interp))
  in
  let interp_no = ref ~-1 in
    sprintf "<table class=\"interp\">\n%s\n</table>"
      (String.concat "\n"
        (List.map
           (fun interp ->
              sprintf "
                  <tr class=\"interp\">
                  <td><input type=\"radio\" name=\"param.interp\" value=\"%d\" /></td>
                  <td>
                  %s
                  </td></tr>"
                (incr interp_no; !interp_no)
                (choice_of_interp interp))
           interps))