{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://hermes.bstein.dev/contracts/hux/v1/artifact.schema.json",
  "title": "HUX artifact",
  "description": "Typed, versioned output (HUX-04). Content lives behind content_ref; versions are immutable and diffable; lineage records what an artifact was derived from; promotion copies a version into a project.",
  "type": "object",
  "additionalProperties": false,
  "required": ["schema", "id", "owner", "type", "title", "current_version", "versions", "sensitivity", "created_at", "updated_at"],
  "properties": {
    "schema": {"const": "hux.artifact.v1"},
    "id": {"$ref": "common.schema.json#/$defs/id"},
    "owner": {"$ref": "common.schema.json#/$defs/user_ref"},
    "conversation_id": {"$ref": "common.schema.json#/$defs/id"},
    "project_id": {"$ref": "common.schema.json#/$defs/id"},
    "type": {"type": "string", "enum": ["markdown", "code", "html", "svg", "image", "json", "csv", "document", "audio"]},
    "language": {"type": "string", "maxLength": 40},
    "title": {"type": "string", "minLength": 1, "maxLength": 200},
    "current_version": {"type": "integer", "minimum": 1},
    "versions": {
      "type": "array",
      "minItems": 1,
      "items": {
        "type": "object",
        "additionalProperties": false,
        "required": ["version", "created_at", "created_by", "content_ref"],
        "properties": {
          "version": {"type": "integer", "minimum": 1},
          "created_at": {"$ref": "common.schema.json#/$defs/timestamp"},
          "created_by": {"$ref": "common.schema.json#/$defs/actor"},
          "message_id": {"type": "string", "maxLength": 120},
          "content_ref": {
            "type": "object",
            "additionalProperties": false,
            "required": ["hash", "bytes", "mime"],
            "properties": {
              "hash": {"$ref": "common.schema.json#/$defs/sha256"},
              "bytes": {"type": "integer", "minimum": 0},
              "mime": {"type": "string", "maxLength": 120}
            }
          },
          "diff_from": {"type": "integer", "minimum": 1},
          "lineage": {
            "type": "object",
            "additionalProperties": false,
            "required": ["artifact_id", "version"],
            "properties": {
              "artifact_id": {"$ref": "common.schema.json#/$defs/id"},
              "version": {"type": "integer", "minimum": 1}
            }
          },
          "note": {"type": "string", "maxLength": 200}
        }
      }
    },
    "promotion": {
      "type": "object",
      "additionalProperties": false,
      "required": ["project_id", "version", "at"],
      "properties": {
        "project_id": {"$ref": "common.schema.json#/$defs/id"},
        "version": {"type": "integer", "minimum": 1},
        "at": {"$ref": "common.schema.json#/$defs/timestamp"}
      }
    },
    "sensitivity": {"$ref": "common.schema.json#/$defs/sensitivity"},
    "created_at": {"$ref": "common.schema.json#/$defs/timestamp"},
    "updated_at": {"$ref": "common.schema.json#/$defs/timestamp"}
  }
}