package org.xwt.js;

/** anything that is callable with the () operator and wasn't compiled from JS code */
public abstract class JSCallable extends JS {

    // return this from get() if the key was actually a method.
    public static final Object METHOD = new Object();

    public Object callMethod(Object method, Object a0, Object a1, Object a2, Object[] rest, int nargs) {
        if (method == null) return call(a0, a1, a2, rest, nargs);
        Class c = this.getClass();
        String descrip = c.getName();
        if (c == Internal.JSCallableStub.class) {
            descrip = ((Internal.JSCallableStub)this).obj.getClass().getName();
        }
        throw new JS.Exn("attempted to call an undefined method ("+method+") on a " + descrip);
    }

    public Object call(Object a0, Object a1, Object a2, Object[] rest, int nargs) {
        Class c = this.getClass();
        String descrip = c.getName();
        if (c == Internal.JSCallableStub.class) {
            descrip = ((Internal.JSCallableStub)this).obj.getClass().getName();
        }
        throw new JS.Exn("you cannot call this object (of type " + descrip + ")");
    }

}