nEngine/examples/sample-game/content/statemachines/cow-milk.yaml

# Production rule (D9 / D19): the engine emits animal-produce per eligible day
# for a mature (milking) cow; this machine turns that event into a milk grant.
# Like chicken-egg it alternates on successive animal-produce events, so the
# milk is granted on every second produce — frequency is language-owned.
id: cow-milk
initial: waiting
states:
  - id: waiting
  - id: laid
    onEnter:
      - action: give-item
        itemId: milk
        qty: 1
      - action: play-sound
        sound: coin
transitions:
  - from: waiting
    to: laid
    on: animal-produce
    when:
      op: eq
      path: payload.animalDefId
      value: cow
  - from: laid
    to: waiting
    on: animal-produce
    when:
      op: eq
      path: payload.animalDefId
      value: cow