{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://backup-tool.invalid/contracts/repository/v1/repository.schema.json",
  "title": "Backup Tool Repository v1",
  "type": "object",
  "additionalProperties": false,
  "required": ["repository_id", "format_version", "digest_algorithm", "compression", "encryption", "created_at"],
  "properties": {
    "repository_id": {"type": "string", "format": "uuid"},
    "format_version": {"const": 1},
    "digest_algorithm": {"const": "sha256"},
    "compression": {"enum": ["none", "zstd"]},
    "encryption": {
      "type": "object",
      "additionalProperties": false,
      "required": ["mode", "key_id"],
      "properties": {
        "mode": {"enum": ["none", "aes-256-gcm"]},
        "key_id": {"type": ["string", "null"], "minLength": 1}
      }
    },
    "created_at": {"type": "string", "format": "date-time"}
  }
}