<*PRAGMA LL*>

MODULE JoinCursor;

IMPORT ScrnCursor, JoinScreen, Cursor, Palette, PlttFrnds,VBTRep;

PROCEDURE New(st: JoinScreen.T): Oracle =
  BEGIN
    RETURN NEW(Oracle, st := st)
  END New;

PROCEDURE Resolve (st: JoinScreen.T; cs: Cursor.T) =
  VAR i: INTEGER; t := st.succ(NIL, i);
  BEGIN
    WHILE t # NIL DO EVAL Palette.ResolveCursor(t, cs); t := st.succ(t, i) END
  END Resolve;

PROCEDURE Apply (           st: JoinScreen.T;
                 <*UNUSED*> cl: Palette.CursorClosure;
                            cs: Cursor.T               ): ScrnCursor.T =
  VAR res := st.cursors[cs.cs];
  BEGIN
    Resolve(st, cs);
    IF res # NIL AND res # PlttFrnds.noCursor THEN RETURN res END;
    RETURN NEW(T, id := 2 * cs.cs + 1, st := st);
  END Apply;

REVEAL
  Oracle = ScrnCursor.Oracle BRANDED OBJECT
             st: JoinScreen.T;
           (*
           OVERRIDES
             load    := Register;
             list    := List;
             lookup  := Lookup;
             builtIn := BuiltIn
           *)
           END;

TYPE
  T = ScrnCursor.T OBJECT
        st: JoinScreen.T;
      (*
      OVERRIDES
        localize := Localize;
        unload   := Unload
      *)
      END;

TYPE Registered = T OBJECT raw: ScrnCursor.Raw OVERRIDES localize := RegisteredLocalize END;

Lookedup = T OBJECT name: TEXT END;

Builtin = T OBJECT cs: Cursor.Predefined END;

PROCEDURE Localize (cs: T): ScrnCursor.Raw RAISES {TrestleComm.Failure, ScrnCursor.Failure} = BEGIN IF cs.buddy = NIL THEN RAISE ScrnCursor.Failure END; RETURN cs.buddy.localize() END Localize;

PROCEDURE Register ( orc: Oracle; READONLY c : ScrnCursor.Raw; nm : TEXT := NIL): ScrnCursor.T RAISES {TrestleComm.Failure} = BEGIN IF orc.st.sts = NIL THEN Crash(); END; RETURN orc.st.sts[0].cursor.load(c, nm); END Register;

PROCEDURE List (orc: Oracle; pat: TEXT; maxResults: CARDINAL := 1): REF ARRAY OF TEXT RAISES {TrestleComm.Failure} = BEGIN IF orc.st.sts = NIL THEN Crash(); END; RETURN orc.st.sts[0].cursor.list(pat, maxResults); END List;

PROCEDURE Lookup (orc: Oracle; name: TEXT): ScrnCursor.T = BEGIN IF orc.st.sts = NIL THEN Crash(); END; RETURN orc.st.sts[0].cursor.lookup(name); END Lookup;

PROCEDURE BuiltIn (orc: Oracle; cs: Cursor.Predefined): ScrnCursor.T = BEGIN IF orc.st.sts = NIL THEN Crash(); END; IF orc.st.sts[0].cursors[cs] = PlttFrnds.noCursor THEN EVAL Palette.ResolveCursor(orc.st.sts[0], Cursor.T{cs}); END; (* if

RETURN orc.st.sts[0].cursors[cs];
  END BuiltIn;
*)

EXCEPTION FatalError;

PROCEDURE Crash () = <* FATAL FatalError *> BEGIN RAISE FatalError; END Crash;

BEGIN END JoinCursor.