How to get, set and unset layer color?

Photoshop UXP Plugin API
,
2

So I found this topic about document bits and managed to get a color of one active layer with:

batchPlay(
    [{
      "_obj": "get",
      "_target": [{
          "_property": "color"
        },
        {
          "_ref": "layer",
          "_enum": "ordinal",
          "_value": "targetEnum"
        }
      ],
      "_options": {
        "dialogOptions": "dontDisplay"
      }
    }], {
      "synchronousExecution": false,
      "modalBehavior": "fail"
    })

But the result is a bit strange. There are seven colors I can assign to layers and five of them return usual color names (red, blue, orange, etc.), but two of them are different. Yellow is yellowColor and green is grain :confused: I’m a bit lost here. Is there some real documentation with full reference about all this batchPlay and descriptors stuff?

Another problem I have - how to get a color of a particular layer I have as an object in UXP script? I guess same question goes for setting the color and unsetting