Can I receive shadows with my unlit shader graph shader?

I understand that this could end up being a futile question, but my goal is to have something similar to Wind Waker, which had shadows, so it can't be impossible, right?

To be clear, my goal is to have a toon/cel shader, so my natural assumption is that it has to be an unlit shader (if not, please tell me how else I could do it, or at least point me to the correct tutorial). My problem is that I have no idea how to check if the specified point is in shadow or not. I've tried looking all over google, but I can't seem to ever get a straight answer.

Anyway, here's my graph (for lack of a better way of showing it):

and in the "Get Color" node, the code is:

 CamDot = .5 - CamDot;
 
 CamDot *= NumShades;
 CamDot = ceil(CamDot);
 CamDot /= NumShades;
 
 NormDot *= NumShades;
 NormDot = ceil(NormDot);
 NormDot /= NumShades;
 
 if (CamDot < 0) CamDot = 0;
 if (NormDot < 0) NormDot = 0;
 
 float bright = CamDot + NormDot;
 
 if (bright <= .5) {
     bright *= 2;
     Out = CShade*(1-bright)+CMain*bright;
 }
 else if (bright <= 1) {
     bright *= 2;
     bright -= 1;
     Out = CMain *(1-bright)+CTint*bright;
 }
 else {
     bright *= 2;
     bright -= 2;
     if (bright > 1) bright = 1;
     Out = CTint*(1-bright*2)+CHiLit*bright*2;
 }

And in the "Get Main Light" (which I got from a tutorial):

 #if SHADERGRAPH_PREVIEW
    Direction = half3(0.5, 0.5, 0);
    Color = 1;
    DistanceAtten = 1;
    ShadowAtten = 1;
 #else
 #if SHADOWS_SCREEN
    half4 clipPos = TransformWorldToHClip(WorldPos);
    half4 shadowCoord = ComputeScreenPos(clipPos);
 #else
    half4 shadowCoord = TransformWorldToShadowCoord(WorldPos);
 #endif
    Light mainLight = GetMainLight(shadowCoord);
    Direction = mainLight.direction;
    Color = mainLight.color;
    DistanceAtten = mainLight.distanceAttenuation;
    ShadowAtten = mainLight.shadowAttenuation;
 #endif

Any help is much appreciated. Thanks!