MODULE ObVectorLightGO;

IMPORT LightGO, ObAux, ObColorProp, ObCommand, ObGO, ObLib, ObLightGO,
       ObPointProp, ObProp, ObProtoLoader, ObValue, Obliq, ProxiedObj,
       SynLocation, VectorLightGO, VectorLightGOProxy;

CONST
  pkgname = "VectorLightGO";

TYPE
  T = ObLightGO.T BRANDED "ObVectorLightGO.T" OBJECT END;

PROCEDURE AddTObj (light : VectorLightGO.T) =
  <* FATAL ObValue.Error, ObValue.Exception *>
  BEGIN
    WITH obj = Obliq.ObjectClone (Obliq.Vals {TProto}),
         raw = NEW (T, what := "<a VectorLightGO.T>", po := light) DO
      Obliq.ObjectUpdate (obj, "raw", raw);
      light.proxy := NEW (ProxiedObj.Proxy, obj := obj);
    END;
  END AddTObj;

PROCEDURE SetupPackage () =

  PROCEDURE NewOpCode (name : TEXT; arity : INTEGER; code : Code) : OpCode =
    BEGIN
      RETURN NEW (OpCode, name := name, arity := arity, code := code);
    END NewOpCode;

  TYPE
    OpCodes = ARRAY OF ObLib.OpCode;
  VAR
    opCodes: REF OpCodes;
  BEGIN
    opCodes := NEW (REF OpCodes, NUMBER (Code));
    opCodes^ :=
        OpCodes {
            NewOpCode ("New",          2, Code.New),
            NewOpCode ("Direction",   -1, Code.Direction),
            NewOpCode ("SetDirection", 2, Code.SetDirection)
        };

    ObLib.Register (NEW (Package, name := pkgname, opCodes := opCodes));
    ObLib.RegisterHelp (pkgname, Help);
  END SetupPackage;

VAR
  TProto : ObValue.Val;

PROCEDURE SetupModule (loader : ObProtoLoader.T) =
  BEGIN
    (*** Retrieve the prototype ***)
    loader.load ("VectorLightGO.obl");
    TProto := loader.get ("VectorLightGO_TProto");

    (*** Register the proxy maker ***)
    VectorLightGOProxy.MkProxyT := AddTObj;
  END SetupModule;

TYPE
  Code = {New, Direction, SetDirection};

  OpCode = ObLib.OpCode OBJECT
    code: Code;
  END;

  Package = ObLib.T OBJECT
  OVERRIDES
    Eval := DoEval;
  END;

PROCEDURE DoEval (self         : Package;
                  opCode       : ObLib.OpCode;
     <* UNUSED *> arity        : ObLib.OpArity;
                  READONLY args: ObValue.ArgArray;
     <* UNUSED *> temp         : BOOLEAN;
                  loc          : SynLocation.T) : ObValue.Val
    RAISES {ObValue.Error, ObValue.Exception} =
  BEGIN
    CASE NARROW (opCode, OpCode).code OF
    | Code.New =>
      WITH color = ObColorProp.GetOverloadedVal (args, 1, self, opCode, loc),
           dir   = ObPointProp.GetOverloadedVal (args, 2, self, opCode, loc),
           light = NEW (VectorLightGO.T).init () DO
        light.setProp (LightGO.Colour.bind (color));
        light.setProp (VectorLightGO.Direction.bind (dir));
        RETURN light.proxy.obj;
      END;
    | Code.Direction =>
      RETURN ObProp.NameToObliq (VectorLightGO.Direction);
    | Code.SetDirection =>
      WITH go  = ObGO.GetArg                  (args, 1, self, opCode, loc),
           dir = ObPointProp.GetOverloadedVal (args, 2, self, opCode, loc) DO
        go.setProp (VectorLightGO.Direction.bind (dir));
        RETURN ObValue.valOk;
      END;
    END;
  END DoEval;

PROCEDURE Help (self : ObCommand.T; arg : TEXT; <* UNUSED *> data : REFANY) =
  BEGIN
    ObAux.Help (self, arg, pkgname);
  END Help;

BEGIN
END ObVectorLightGO.