adding time dependent curve

Dear AE fellows, I'm starting to learn JavaScript for AE.

I'd like to make a script which

1) adds to the layer time dependent vector curves (vector curves with  vertices and tangents evolving with time).

2) add "time slider" so the user can  control the evolution and add key frames. (In most cases the curve consists of up to twenty vertices and the contour is progressively drawn as time changes)

Is it possible with JavaScript?

So far I found how to draw the static curve.

var myShape = new Shape();

myShape.vertices = [[300,50],[200,150],[300,250],[400,150]];

myShape.inTangents = [[55.23,0],[0,-55.23],[-155.23,0],[0,55.23]];

myShape.outTangents = [[-55.23,0],[0,100.23],[55.23,0],[0,-55.23]];

myShape.closed = false;

myShapeGroup.property(1).property("ADBE Vector Shape").setValue(myShape);

Yaroslav.