(* Copyright (C) 2004-2005, 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 Printf ;;

let instance =
  let dbd = lazy (
    HMysql.quick_connect
      ~host:(Helm_registry.get "db.host")
      ~user:(Helm_registry.get "db.user")
      ~database:(Helm_registry.get "db.database")
      ())
  in
  fun () -> Lazy.force dbd


let xpointer_RE = Pcre.regexp "#.*$"
let file_scheme_RE = Pcre.regexp "^file://"

let clean_owner_environment () =
  let dbd = instance () in
  let owner = (Helm_registry.get "matita.owner") in
  let obj_tbl = MetadataTypes.obj_tbl () in
  let sort_tbl = MetadataTypes.sort_tbl () in
  let rel_tbl = MetadataTypes.rel_tbl () in
  let name_tbl =  MetadataTypes.name_tbl () in
  let count_tbl = MetadataTypes.count_tbl () in
  let tbls = [ 
    (obj_tbl,`RefObj) ; (sort_tbl,`RefSort) ; (rel_tbl,`RefRel) ;
    (name_tbl,`ObjectName) ; (count_tbl,`Count) ] 
  in
  let statements = 
    (SqlStatements.drop_tables tbls) @ (SqlStatements.drop_indexes tbls)
  in
  let owned_uris =
    try
      MetadataDb.clean ~dbd
    with Mysql.Error _ as exn ->
      match HMysql.errno dbd with 
      | Mysql.No_such_table -> []
      | _ -> raise exn
  in
  List.iter
    (fun uri ->
      let uri = Pcre.replace ~rex:xpointer_RE ~templ:"" uri in
      List.iter
        (fun suffix ->
          try
           MatitaMisc.safe_remove (Http_getter.resolve (uri ^ suffix))
          with Http_getter_types.Key_not_found _ -> ())
        [""; ".body"; ".types"])
    owned_uris;
  List.iter (fun statement -> 
    try
      ignore (HMysql.exec dbd statement)
    with Mysql.Error _ as exn ->
      match HMysql.errno dbd with 
      | Mysql.Bad_table_error 
      | Mysql.No_such_index | Mysql.No_such_table -> () 
      | _ -> raise exn
    ) statements;
;;

let create_owner_environment () = 
  let dbd = instance () in
  let obj_tbl = MetadataTypes.obj_tbl () in
  let sort_tbl = MetadataTypes.sort_tbl () in
  let rel_tbl = MetadataTypes.rel_tbl () in
  let name_tbl =  MetadataTypes.name_tbl () in
  let count_tbl = MetadataTypes.count_tbl () in
  let tbls = [ 
    (obj_tbl,`RefObj) ; (sort_tbl,`RefSort) ; (rel_tbl,`RefRel) ;
    (name_tbl,`ObjectName) ; (count_tbl,`Count) ] 
  in
  let statements = 
    (SqlStatements.create_tables tbls) @ (SqlStatements.create_indexes tbls)
  in
  List.iter (fun statement -> 
    try
      ignore (HMysql.exec dbd statement)
    with
      exn -> 
         let status = HMysql.status dbd in
         match status with 
         | Mysql.StatusError Mysql.Table_exists_error -> ()
         | Mysql.StatusError Mysql.Dup_keyname -> ()
         | Mysql.StatusError _ -> raise exn
         | _ -> ()
      ) statements
;;

(* removes uri from the ownerized tables, and returns the list of other objects
 * (theyr uris) that ref the one removed. 
 * AFAIK there is no need to return it, since the MatitaTypes.staus should
 * contain all defined objects. but to double check we do not garbage the
 * metadata...
 *)
let remove_uri uri =
  let obj_tbl = MetadataTypes.obj_tbl () in
  let sort_tbl = MetadataTypes.sort_tbl () in
  let rel_tbl = MetadataTypes.rel_tbl () in
  let name_tbl =  MetadataTypes.name_tbl () in
  (*let conclno_tbl = MetadataTypes.conclno_tbl () in
  let conclno_hyp_tbl = MetadataTypes.fullno_tbl () in*)
  let count_tbl = MetadataTypes.count_tbl () in
  
  let dbd = instance () in
  let suri = UriManager.string_of_uri uri in 
  let query table suri = sprintf 
    "DELETE FROM %s WHERE source LIKE '%s%%'" table (HMysql.escape suri)
  in
  List.iter (fun t -> 
    try 
      ignore (HMysql.exec dbd (query t suri))
    with
      exn -> raise exn (* no errors should be accepted *)
    )
  [obj_tbl;sort_tbl;rel_tbl;name_tbl;(*conclno_tbl;conclno_hyp_tbl*)count_tbl];
  (* and now the debug job *)  
  let dbg_q = 
    sprintf "SELECT source FROM %s WHERE h_occurrence LIKE '%s%%'" obj_tbl
    (HMysql.escape suri)
  in
  try 
    let rc = HMysql.exec dbd dbg_q in
    let l = ref [] in
    HMysql.iter rc (fun a -> match a.(0) with None ->()|Some a -> l := a:: !l);
    let l = List.sort Pervasives.compare !l in
    MatitaMisc.list_uniq l
  with
    exn -> raise exn (* no errors should be accepted *)

let xpointers_of_ind uri =
  let dbd = instance () in
  let name_tbl =  MetadataTypes.name_tbl () in
  let query = sprintf 
    "SELECT source FROM %s WHERE source LIKE '%s#xpointer%%'" name_tbl 
      (HMysql.escape (UriManager.string_of_uri uri))
  in
  let rc = HMysql.exec dbd query in
  let l = ref [] in
  HMysql.iter rc (fun a ->  match a.(0) with None ->()|Some a -> l := a:: !l);
  List.map UriManager.uri_of_string !l