(* Copyright (C) 2004, 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://helm.cs.unibo.it/
 *)

open MetadataTypes

open Printf

let prepare_insert () =
  (*
  let insert_owner a b =
    sprintf "INSERT %s VALUES (\"%s\", \"%s\")" (owners_tbl ())a b
  in
  *)
  let insert_sort  a b c d =
    sprintf "INSERT %s VALUES (\"%s\", \"%s\", %d, \"%s\")" (sort_tbl ())a b c d
  in
  let insert_rel a b c =
    sprintf "INSERT %s VALUES (\"%s\", \"%s\", %d)" (rel_tbl ()) a b c
  in
  let insert_obj a b c d =
    sprintf "INSERT %s VALUES (\"%s\", \"%s\", \"%s\", %s)" (obj_tbl ()) a b c d
  in
  ((*insert_owner, *)insert_sort, insert_rel, insert_obj)

let execute_insert dbd ((*insert_owner, *)insert_sort, insert_rel, insert_obj)
  uri (sort_cols, rel_cols, obj_cols)
=
  (* ignore (Mysql.exec dbd (insert_owner uri owner)); *)
  List.iter (function
      | [`String a; `String b; `Int c; `String d] ->
          ignore (Mysql.exec dbd (insert_sort a b c d))
      | _ -> assert false)
    sort_cols;
  List.iter (function
      | [`String a; `String b; `Int c] ->
          ignore (Mysql.exec dbd (insert_rel a b c))
      | _ -> assert false)
    rel_cols;
  List.iter (function
      | [`String a; `String b; `String c; `Int d] ->
          ignore (Mysql.exec dbd (insert_obj a b c (string_of_int d)))
      | [`String a; `String b; `String c; `Null] ->
          ignore (Mysql.exec dbd (insert_obj a b c "NULL"))
      | _ -> assert false)
    obj_cols

let insert_const_no dbd uri =
  let inconcl_no =
    sprintf "INSERT %s SELECT \"%s\", COUNT(DISTINCT h_occurrence) FROM %s WHERE (h_position=\"%s\" OR h_position=\"%s\") AND source LIKE \"%s%%\""
      (conclno_tbl ()) uri (obj_tbl ()) inconcl_pos mainconcl_pos uri
  in
  let concl_hyp =
    sprintf "INSERT %s
        SELECT \"%s\",COUNT(DISTINCT h_occurrence)
        FROM %s
        WHERE NOT (h_position=\"%s\") AND (source = \"%s\")"
      (conclno_hyp_tbl ()) uri (obj_tbl ()) inbody_pos uri
  in
  ignore (Mysql.exec dbd inconcl_no);
  ignore (Mysql.exec dbd concl_hyp)

let insert_name ~dbd ~uri ~name =
  let query =
    sprintf "INSERT %s VALUES (\"%s\", \"%s\")" (name_tbl ()) uri name
  in
  ignore (Mysql.exec dbd query)

type columns =
  MetadataPp.t list list * MetadataPp.t list list * MetadataPp.t list list

  (* TODO ZACK: verify if an object has already been indexed *)
let already_indexed _ = false

let index_constant ~dbd =
  let query = prepare_insert () in
  fun ~uri ~body ~ty  ->
    if not (already_indexed uri) then begin
      let name = UriManager.name_of_uri uri in
      let uri = UriManager.string_of_uri uri in
      let metadata = MetadataExtractor.compute ~body ~ty in
      let columns = MetadataPp.columns_of_metadata ~about:uri metadata in
      execute_insert dbd query uri (columns :> columns);
      insert_const_no dbd uri;
      insert_name ~dbd ~uri ~name
    end

let index_inductive_def ~dbd =
  let query = prepare_insert () in
  fun ~uri ~types ->
    if not (already_indexed uri) then begin
      let metadata = MetadataExtractor.compute_ind ~uri ~types in
      let uri_of (a,b,c) = a in
      let uris = UriManager.string_of_uri uri :: List.map uri_of metadata in
      let uri = UriManager.string_of_uri uri in
      let columns = MetadataPp.columns_of_ind_metadata metadata in
      execute_insert dbd query uri (columns :> columns);
      List.iter (insert_const_no dbd) uris;
      List.iter (fun (uri, name, _) -> insert_name ~dbd ~uri ~name) metadata
    end

let clean ~(dbd:Mysql.dbd) =
  let owned_uris =  (* list of uris in list-of-columns format *)
    let query = sprintf "SELECT source FROM %s" (obj_tbl ()) in
    let result = Mysql.exec dbd query in
    let uris = Mysql.map result (fun cols ->
      match cols.(0) with
      | Some src -> src
      | None -> assert false) in
    (* and now some stuff to remove #xpointers and duplicates *)
    uris
  in
  let del_from tbl =
    let query s = 
      sprintf "DELETE FROM %s WHERE source LIKE \"%s%%\"" (tbl ()) s 
    in
    List.iter
      (fun source_col -> ignore (Mysql.exec dbd (query source_col)))
      owned_uris
  in
  List.iter del_from
    [sort_tbl; rel_tbl; obj_tbl; conclno_tbl; conclno_hyp_tbl; name_tbl];
  owned_uris