{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://yukihamada.github.io/openformats/collection/v1.json",
  "title": "collection.json v1 — open collection / album / playlist / series format",
  "description": "1 まとまり = 1 JSON。曲・動画・記事・本などを束ねる (アルバム/プレイリスト/シリーズ/展示)。各要素は他フォーマットの id を参照。MIT。",
  "allOf": [{ "$ref": "https://yukihamada.github.io/openformats/core/envelope/v1.json" }],
  "type": "object",
  "required": ["kind", "id", "items"],
  "properties": {
    "kind": { "const": "collection" },
    "collection_type": {
      "type": "string",
      "enum": ["album", "playlist", "series", "exhibition", "course", "magazine", "bundle", "other"]
    },
    "description": { "type": "string" },
    "cover": { "type": "string", "description": "image.json の id または参照。" },
    "items": {
      "type": "array",
      "description": "順序付きの要素。",
      "items": {
        "type": "object",
        "required": ["ref"],
        "properties": {
          "ref": { "type": "string", "description": "他作品の id (music/movie/article/book/...)。" },
          "kind": { "type": "string", "description": "参照先の kind。" },
          "order": { "type": "integer" },
          "note": { "type": "string" }
        },
        "additionalProperties": true
      }
    },
    "total_duration_sec": { "type": "number" }
  }
}