/* Copyright (C) 2000, 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/.
 */

%{
   module T = Types
   
   let out t s = () (* prerr_endline ("-- " ^ t ^ " " ^ s) *)

   let trim = HExtlib.trim_blanks

   let hd = List.hd

   let cat x = String.concat " " x

   let mk_vars local idents =
      let map ident = T.Inline (local, T.Var, trim ident, "") in
      List.map map idents

   let strip2 s =
      String.sub s 1 (String.length s - 2)

   let strip1 s = 
      String.sub s 1 (String.length s - 1)

   let coercion str = 
      [T.Coercion (false, str); T.Coercion (true, str)]

   let notation str =
      [T.Notation (false, str); T.Notation (true, str)]
%}
   %token <string> SPC STR IDENT INT EXTRA AC OP CP OC CC OQ CQ DEF FS COE CN SC
   %token <string> ABBR IN LET TH PROOF QED VAR AX IND SEC END UNX REQ XP IP SET NOT LOAD ID COERC
   %token EOF
   
   %start items
   %type <Types.items> items
%%
   comment:
      | OQ verbatims CQ { $1 ^ $2 ^ $3 }
   ;
   spc:
      | SPC     { $1 }
      | comment { $1 }
   ;
   spcs:
     |          { ""      }
     | spc spcs { $1 ^ $2 }
   ;
   rspcs:
     |           { ""      }
     | SPC rspcs { $1 ^ $2 }
   ;
   xident:
      | IDENT { $1 }
      | LET   { $1 }
      | TH    { $1 }
      | QED   { $1 }
      | PROOF { $1 }
      | VAR   { $1 }
      | AX    { $1 }
      | IND   { $1 }
      | SEC   { $1 }
      | END   { $1 }
      | UNX   { $1 }
      | REQ   { $1 }
      | LOAD  { $1 }
      | NOT   { $1 }
      | ID    { $1 }
      | COERC { $1 }
   ;
   fs: FS spcs { $1 ^ $2 };
   ident: xident spcs { $1 ^ $2 };
   th: TH spcs { $1 ^ $2 };
   xlet: LET spcs { $1 ^ $2 };
   proof: PROOF spcs { $1 ^ $2 };
   qed: QED spcs { $1 ^ $2 };
   sec: SEC spcs { $1 ^ $2 };
   xend: END spcs { $1 ^ $2 };
   unx: UNX spcs { $1 ^ $2 };
   def: DEF spcs { $1 ^ $2 };
   op: OP spcs { $1 ^ $2 };
   abbr: ABBR spcs { $1 ^ $2 };
   var: VAR spcs { $1 ^ $2 };
   ax: AX spcs { $1 ^ $2 };
   req: REQ spcs { $1 ^ $2 };
   load: LOAD spcs { $1 ^ $2 };
   xp: XP spcs { $1 ^ $2 };
   ip: IP spcs { $1 ^ $2 };
   ind: IND spcs { $1 ^ $2 };
   set: SET spcs { $1 ^ $2 };
   notation: NOT spcs { $1 ^ $2 };
   oc: OC spcs { $1 ^ $2 };
   coe: COE spcs { $1 ^ $2 };
   cn: CN spcs { $1 ^ $2 };
   sc: SC spcs { $1 ^ $2 };
   str: STR spcs { $1 ^ $2 };
   id: ID spcs { $1 ^ $2 };
   coerc: COERC spcs { $1 ^ $2 };

   idents:
      | ident        { [$1]     }
      | ident idents { $1 :: $2 }
   ;
   
   cnot:
      | EXTRA { $1 }
      | INT   { $1 }
   ;
   cnots:
      | cnot spcs       { $1 ^ $2      }
      | cnot spcs cnots { $1 ^ $2 ^ $3 }
   ;
   
   xstrict:
      | AC               { $1           }
      | INT              { $1           }
      | EXTRA            { $1           }
      | CN               { $1           }
      | SC               { $1           }
      | OC               { $1           }
      | CC               { $1           }
      | COE              { $1           }
      | STR              { $1           }   
      | abbr extends0 IN { $1 ^ $2 ^ $3 }
      | op extends1 CP   { $1 ^ $2 ^ $3 }
      
   ;
   strict:
      | xstrict { $1 }
      | IDENT   { $1 } 
      | SET     { $1 }
      | NOT     { $1 }
   ;
   restrict: 
      | strict  { $1 }
      | IN      { $1 }
      | CP      { $1 }
   ;
   xre:
      | xstrict { $1 }
      | IN      { $1 }
      | CP      { $1 }   
   ;
   restricts:
      | restrict spcs           { $1 ^ $2      }
      | restrict spcs restricts { $1 ^ $2 ^ $3 }
   ;
   xres:
      | xre spcs           { $1 ^ $2      }
      | xre spcs restricts { $1 ^ $2 ^ $3 }   
   ;
   extend0:
      | strict { $1 }
      | DEF    { $1 }
   ;
   extends0:
      | extend0 spcs          { $1 ^ $2      }
      | extend0 spcs extends0 { $1 ^ $2 ^ $3 }
   ;
   extend1:
      | strict { $1 }
      | DEF    { $1 }
      | IN     { $1 }
   ;
   extends1:
      | extend1 spcs          { $1 ^ $2      }
      | extend1 spcs extends1 { $1 ^ $2 ^ $3 }
   ;
   unexport_rr:
      | AC    { $1 }
      | INT   { $1 }
      | IDENT { $1 }
      | EXTRA { $1 }
      | CN    { $1 }
      | COE   { $1 }
      | STR   { $1 }   
      | OP    { $1 }
      | ABBR  { $1 }
      | IN    { $1 }
      | CP    { $1 }
      | DEF   { $1 }
      | SET   { $1 }
      | NOT   { $1 }
      | LOAD  { $1 }
      | ID    { $1 } 
      | COERC { $1 } 
   ;
   unexport_r:
      | unexport_rr  { $1, []                   }
      | oc fields CC { $1 ^ fst $2 ^ $3, snd $2 }
   ;
   unexports_r:
      | unexport_r spcs             { fst $1 ^ $2, snd $1                   }
      | unexport_r spcs unexports_r { fst $1 ^ $2 ^ fst $3, snd $1 @ snd $3 } 
   ;
   field: 
      | ident cn unexports_r  
         { $1 ^ $2 ^ fst $3, snd $3                      }
      | ident coe unexports_r 
         { $1 ^ $2 ^ fst $3, snd $3 @ coercion (trim $1) }
   ;  
   fields:
      | field           { $1                                      }
      | field sc fields { fst $1 ^ $2 ^ fst $3, snd $1 @ snd $3   } 
      | cnots           { $1, []                                  }
      | error           { out "ERROR" "fields"; failwith "fields" }
   ;
   unexport:
      | unexport_r { $1     }
      | SC         { $1, [] }
      | CC         { $1, [] }
   ;   
   unexports:
      | unexport spcs           { fst $1 ^ $2, snd $1                   }
      | unexport spcs unexports { fst $1 ^ $2 ^ fst $3, snd $1 @ snd $3 }
   ;
   verbatim:
      | unexport_rr { $1 }
      | OC          { $1 }
      | CC          { $1 }
      | SC          { $1 }
      | TH          { $1 }       
      | LET         { $1 }       
      | VAR         { $1 }
      | AX          { $1 }
      | IND         { $1 }
      | SEC         { $1 }
      | END         { $1 }
      | UNX         { $1 }
      | REQ         { $1 } 
      | XP          { $1 } 
      | IP          { $1 } 
      | QED         { $1 }
      | PROOF       { $1 }
      | FS          { $1 }
      | SPC         { $1 } 
   ;
   verbatims:
      |                    { ""      }
      | verbatim verbatims { $1 ^ $2 }
   ;   
   step:
      | macro_step   { $1 }
      | restricts FS { [] }
   ;
   steps:
      | step spcs       { []      }
      | step spcs steps { $1 @ $3 }
   ;
   
   qid:
      | xident { [$1]            }
      | qid AC { strip1 $2 :: $1 }
   ;
   
   macro_step:
      | th ident restricts fs proof FS steps qed FS 
         { out "TH" $2; $7 @ [T.Inline (false, T.Con, trim $2, "")]     }
      | th ident restricts fs proof restricts FS
         { out "TH" $2; [T.Inline (false, T.Con, trim $2, "")]          }
      | th ident restricts fs steps qed FS 
         { out "TH" $2; $5 @ [T.Inline (false, T.Con, trim $2, "")]     }
      | th ident restricts def restricts FS
         { out "TH" $2; [T.Inline (false, T.Con, trim $2, "")]          }
      | th ident def restricts FS
         { out "TH" $2; [T.Inline (false, T.Con, trim $2, "")]          }
      | xlet ident restricts fs proof FS steps qed FS 
         { out "LET" $2; $7 @ [T.Inline (true, T.Con, trim $2, "")]     }
      | xlet ident restricts fs proof restricts FS
         { out "LET" $2; [T.Inline (true, T.Con, trim $2, "")]          }
      | xlet ident restricts fs steps qed FS 
         { out "LET" $2; $5 @ [T.Inline (true, T.Con, trim $2, "")]     }
      | xlet ident restricts def restricts FS
         { out "LET" $2; [T.Inline (true, T.Con, trim $2, "")]          }
      | xlet ident def restricts FS
         { out "LET" $2; [T.Inline (true, T.Con, trim $2, "")]          }
      | var idents xres FS
         { out "VAR" (cat $2); mk_vars true $2                          }
      | ax idents xres FS
         { out "AX" (cat $2); mk_vars false $2                          }
      | ind ident unexports FS
         { out "IND" $2; T.Inline (false, T.Ind, trim $2, "") :: snd $3 }
      | sec ident FS
         { out "SEC" $2; [T.Section (true, trim $2, $1 ^ $2)]           }
      | xend ident FS
         { out "END" $2; [T.Section (false, trim $2, $1 ^ $2)]          }
      | unx unexports FS 
         { out "UNX" (fst $2); [T.Unexport ($1 ^ fst $2 ^ trim $3)]     }
      | req xp ident FS
         { out "REQ" $3; [T.Include (trim $3)]                          }
      | req ip ident FS
         { out "REQ" $3; [T.Include (trim $3)]                          }
      | req ident FS
         { out "REQ" $2; [T.Include (trim $2)]                          } 
      | load str FS
         { out "REQ" $2; [T.Include (strip2 (trim $2))]                 }
      | coerc qid spcs cn unexports FS
         { out "COERCE" (hd $2); coercion (hd $2)                       }
      | id coerc qid spcs cn unexports FS
         { out "COERCE" (hd $3); coercion (hd $3)                       }
      | th ident error 
         { out "ERROR" $2; failwith ("macro_step " ^ $2)                }
      | ind ident error 
         { out "ERROR" $2; failwith ("macro_step " ^ $2)                }
      | var idents error 
         { let vs = cat $2 in
	   out "ERROR" vs; failwith ("macro_step " ^ vs)                }
      | ax idents error 
         { let vs = cat $2 in
	   out "ERROR" vs; failwith ("macro_step " ^ vs)                }
   ;
   item:
      | OQ verbatims CQ       { [T.Comment $2]                       }
      | macro_step            { $1                                   }
      | set unexports FS      { [T.Unexport ($1 ^ fst $2 ^ trim $3)] }
      | notation unexports FS { notation ($1 ^ fst $2 ^ trim $3)     }
      | error                 { out "ERROR" "item"; failwith "item"  }
    ;
    items:
      | rspcs EOF        { []      }
      | rspcs item items { $2 @ $3 }
    ;