Adjustment Layer Getting Preset Kind

Photoshop
9

Not sure if it’s the only way, but you can get this from layers json property.

    {
        _obj: "get",
        _target: [
            {_property: "json"},
            { _ref: "layer",_enum: "ordinal", _value: "targetEnum"},
        ],
        _options: {dialogOptions: "dontDisplay"}
    }

There you’ll need to JSON.parse(propertyValue) and you’ll find layers. Then you could recursively iterate through these layers and find the one you need by ID. You’ll get something like that:

        {
          "id": 18,
          "index": 4,
          "type": "adjustmentLayer",
          "name": "Curves 1",
          "bounds": {"top": 0, "left": 0, "bottom": 2048, "right": 3072},
          "visible": true,
          "clipped": false,
          "adjustment": {
            "presetKind": "presetKindCustom",
            "adjustment": [
              {
                "channel": "composite",
                "curve": [
                  {"horizontal": 0, "vertical": 0},
                  {"horizontal": 147, "vertical": 106},
                  {"horizontal": 219, "vertical": 136},
                  {"horizontal": 255, "vertical": 255}
                ]
              }
            ],
            "class": "curves"
          },
          "mask": {
            "bounds": {"top": 0, "left": 0, "bottom": 2048, "right": 3072},
            "extendWithWhite": true
          },
          "generatorSettings": false
        }

Just checked and even if you reset all points on the curve, it still gives custom, but without adjustment:

        {
          "id": 18,
          "index": 4,
          "type": "adjustmentLayer",
          "name": "Curves 1",
          "bounds": {"top": 0, "left": 0, "bottom": 2048, "right": 3072},
          "visible": true,
          "clipped": false,
          "adjustment": {
            "presetKind": "presetKindCustom",
            "class": "curves"
          },
          "mask": {
            "bounds": {"top": 0, "left": 0, "bottom": 2048, "right": 3072},
            "extendWithWhite": true
          },
          "generatorSettings": false
        }

Freshly created layer has exact same structure, but "presetKind": "presetKindDefault"