{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://raw.githubusercontent.com/api-evangelist/knock-app/main/json-schema/knock-message-schema.json",
  "title": "Knock Message",
  "description": "A per-recipient delivery record produced by a Knock workflow run or broadcast. Carries channel, provider, status, engagement, and content references for one message to one recipient.",
  "type": "object",
  "required": ["__typename", "id", "channel_id", "recipient", "workflow", "status", "inserted_at"],
  "properties": {
    "__typename": {
      "type": "string",
      "const": "Message"
    },
    "id": {
      "type": "string",
      "description": "Globally unique Knock-assigned identifier (typically a ULID)."
    },
    "channel_id": {
      "type": "string",
      "format": "uuid",
      "description": "ID of the Knock channel that produced this message."
    },
    "recipient": {
      "oneOf": [
        { "type": "string" },
        {
          "type": "object",
          "properties": {
            "id": { "type": "string" },
            "collection": { "type": "string" }
          }
        }
      ],
      "description": "Either a string user id, or an object reference identifying a non-user recipient."
    },
    "workflow": {
      "type": "string",
      "description": "Key of the workflow that triggered this message."
    },
    "tenant": {
      "type": ["string", "null"],
      "description": "Tenant id, when the message was triggered with a tenant."
    },
    "status": {
      "type": "string",
      "enum": [
        "queued",
        "sent",
        "delivered",
        "delivery_attempted",
        "undelivered",
        "not_sent",
        "bounced"
      ]
    },
    "engagement_statuses": {
      "type": "array",
      "items": {
        "type": "string",
        "enum": ["seen", "unseen", "read", "unread", "interacted", "link_clicked", "archived", "unarchived"]
      }
    },
    "read_at":        { "type": ["string", "null"], "format": "date-time" },
    "seen_at":        { "type": ["string", "null"], "format": "date-time" },
    "archived_at":    { "type": ["string", "null"], "format": "date-time" },
    "interacted_at":  { "type": ["string", "null"], "format": "date-time" },
    "link_clicked_at":{ "type": ["string", "null"], "format": "date-time" },
    "inserted_at":    { "type": "string", "format": "date-time" },
    "updated_at":     { "type": "string", "format": "date-time" },
    "source": {
      "type": "object",
      "description": "How this message originated (workflow trigger, broadcast, schedule, etc.).",
      "properties": {
        "key":         { "type": "string" },
        "version_id":  { "type": "string" },
        "step_ref":    { "type": "string" }
      }
    },
    "data": {
      "type": ["object", "null"],
      "description": "Trigger-time payload available for templating and conditions."
    },
    "metadata": {
      "type": ["object", "null"],
      "description": "Channel/provider-specific metadata captured at send time."
    },
    "scheduled_at": { "type": ["string", "null"], "format": "date-time" }
  },
  "additionalProperties": true
}