status.move

The status.move primitive tracks the lifecycle of an assembly. Its AssemblyStatus value is stored inside the assembly; only modules in the world package can change it. The assembly layer handles authorization and other operational requirements.

State and events

classDiagram
    class AssemblyStatus {
        +Status status
    }
    class Status {
        <<enumeration>>
        NULL
        OFFLINE
        ONLINE
    }
    class StatusChangedEvent {
        +ID assembly_id
        +TenantItemId assembly_key
        +Status status
        +Action action
    }
    AssemblyStatus --> Status
    StatusChangedEvent --> Status

Status has NULL, OFFLINE, and ONLINE variants. Action has ANCHORED, ONLINE, OFFLINE, and UNANCHORED variants. AssemblyStatus stores only the current Status; it does not store the assembly ID, key, timestamps, or a cooldown. The ID and key are passed to each transition for event emission.

Transitions

stateDiagram-v2
    [*] --> OFFLINE: anchor(assembly_id, assembly_key)
    OFFLINE --> ONLINE: online(...)
    ONLINE --> OFFLINE: offline(...)
    OFFLINE --> NULL: unanchor(...)
    ONLINE --> NULL: unanchor(...)

Package function	Requirement	Result
`anchor(assembly_id, assembly_key)`	Called by a module in the package	Returns `AssemblyStatus` in `OFFLINE` state; emits `ANCHORED`.
`online(&mut assembly_status, assembly_id, assembly_key)`	Current state is `OFFLINE`	Changes to `ONLINE`; emits `ONLINE`.
`offline(&mut assembly_status, assembly_id, assembly_key)`	Current state is `ONLINE`	Changes to `OFFLINE`; emits `OFFLINE`.
`unanchor(assembly_status, assembly_id, assembly_key)`	Current state is `OFFLINE` or `ONLINE`	Consumes the status; emits `UNANCHORED` with `NULL` status.

Invalid transitions abort with EAssemblyInvalidStatus. Each transition emits StatusChangedEvent containing the assembly ID, its TenantItemId, resulting status, and action. unanchor does not store a NULL status: the event signals removal to indexers.

The public status(&AssemblyStatus) and is_online(&AssemblyStatus) accessors expose state to callers. The primitive does not itself check fuel or energy, enforce a cooldown, or authorize a caller by ownership capability. Those checks belong to the assembly and other composing modules.