{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://nightscout.github.io/schemas/event-envelope.schema.json",
  "title": "EventEnvelope",
  "description": "Wrapper for all control plane events, providing consistent ordering, audit, and replay capabilities",
  "type": "object",
  "required": ["eventId", "eventType", "issuer", "timestamp", "payload"],
  "properties": {
    "eventId": {
      "type": "string",
      "format": "uuid",
      "description": "Stable UUID for this event"
    },
    "eventType": {
      "type": "string",
      "description": "Dot-notation event type",
      "enum": [
        "profile.definition.created",
        "profile.definition.updated",
        "profile.selection.changed",
        "override.definition.created",
        "override.definition.updated",
        "override.instance.activated",
        "override.instance.ended",
        "override.instance.canceled",
        "override.instance.superseded",
        "policy.composition.computed",
        "delivery.requested",
        "delivery.observed",
        "delivery.reconciled",
        "controller.registered",
        "controller.deregistered",
        "capability.snapshot.updated"
      ]
    },
    "cursor": {
      "type": "integer",
      "minimum": 0,
      "description": "Server-assigned monotonic global ordering"
    },
    "issuer": {
      "type": "string",
      "description": "Identifier for the entity that issued this event (controller, user, agent)"
    },
    "issuerSeq": {
      "type": "integer",
      "minimum": 0,
      "description": "Monotonic sequence number per issuer for ordering"
    },
    "idempotencyKey": {
      "type": "string",
      "description": "Client-provided key for retry deduplication"
    },
    "timestamp": {
      "type": "string",
      "format": "date-time",
      "description": "ISO 8601 timestamp when event was created"
    },
    "refs": {
      "type": "array",
      "description": "References to related objects",
      "items": {
        "type": "object",
        "required": ["refType", "refId"],
        "properties": {
          "refType": {
            "type": "string",
            "description": "Type of referenced object",
            "enum": [
              "profileDefinition",
              "profileSelection",
              "overrideDefinition",
              "overrideInstance",
              "policyComposition",
              "deliveryRequest",
              "deliveryObservation",
              "controllerInstance",
              "capabilitySnapshot"
            ]
          },
          "refId": {
            "type": "string",
            "description": "ID or content hash of referenced object"
          }
        }
      }
    },
    "payload": {
      "type": "object",
      "description": "The actual event data (schema depends on eventType)"
    },
    "metadata": {
      "type": "object",
      "description": "Optional extensible metadata",
      "properties": {
        "bridgeSource": {
          "type": "string",
          "description": "If synthesized from legacy data, the source collection"
        },
        "bridgeSourceId": {
          "type": "string",
          "description": "If synthesized, the source document ID"
        }
      }
    }
  }
}