# E30 §6.2 Control State Model — encoded as a transition table.
#
# Each row is a (from, on) -> (to [, then] [, ack]) tuple:
#   from: source state
#   on:   triggering event (operator_*, host_request_*)
#   to:   destination state for the transition (optional; omit for "stay put")
#   then: an automatic follow-on transition (used to advance through the
#         transient AttemptOnline state in one logical step)
#   ack:  the SEMI-mandated ack code returned to the host (only relevant for
#         host_request_* events; ignored for operator_* events)
#
# Rows are evaluated by first match on (from, on). An empty `to`/`then` means
# no state change. Unlisted (from, on) pairs are treated as "no transition,
# event ignored" (operator events) or "ack = NotAccept" (host events).

initial: HostOffline

transitions:
  # --- Host: Request Online (S1F17) -------------------------------------
  - {from: HostOffline,      on: host_request_online,  to: AttemptOnline, then: OnlineRemote, ack: Accept}
  - {from: OnlineLocal,      on: host_request_online,  ack: AlreadyOnline}
  - {from: OnlineRemote,     on: host_request_online,  ack: AlreadyOnline}
  - {from: EquipmentOffline, on: host_request_online,  ack: NotAccept}
  - {from: AttemptOnline,    on: host_request_online,  ack: NotAccept}

  # --- Host: Request Offline (S1F15) ------------------------------------
  - {from: OnlineLocal,      on: host_request_offline, to: HostOffline, ack: Accept}
  - {from: OnlineRemote,     on: host_request_offline, to: HostOffline, ack: Accept}
  # Idempotent when already offline from host's view.
  - {from: EquipmentOffline, on: host_request_offline, ack: Accept}
  - {from: HostOffline,      on: host_request_offline, ack: Accept}
  - {from: AttemptOnline,    on: host_request_offline, ack: Accept}

  # --- Operator: Switch Online -----------------------------------------
  - {from: EquipmentOffline, on: operator_online,  to: AttemptOnline, then: OnlineLocal}
  - {from: HostOffline,      on: operator_online,  to: AttemptOnline, then: OnlineLocal}

  # --- Operator: Switch Offline ----------------------------------------
  - {from: OnlineLocal,      on: operator_offline, to: HostOffline}
  - {from: OnlineRemote,     on: operator_offline, to: HostOffline}
  - {from: AttemptOnline,    on: operator_offline, to: HostOffline}

  # --- Operator: Local <-> Remote --------------------------------------
  - {from: OnlineRemote,     on: operator_local,   to: OnlineLocal}
  - {from: OnlineLocal,      on: operator_remote,  to: OnlineRemote}