{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://bare-os.dev/schemas/mbr-layout.schema.json",
  "title": "Bare OS mbr_layout RPC payload",
  "description": "Shape for bare_os.mbr_layout response payload emitted by seeder/protocol channel.",
  "type": "object",
  "additionalProperties": false,
  "required": [
    "role",
    "protocol",
    "primaryHex",
    "failoverHexes",
    "keyCount",
    "activeIndex",
    "atMs"
  ],
  "properties": {
    "role": { "const": "seeder" },
    "protocol": { "const": "bare-os-v1" },
    "primaryHex": {
      "type": ["string", "null"],
      "pattern": "^[0-9a-f]{64}$"
    },
    "failoverHexes": {
      "type": "array",
      "items": {
        "type": "string",
        "pattern": "^[0-9a-f]{64}$"
      },
      "maxItems": 31
    },
    "keyCount": { "type": "integer", "minimum": 0, "maximum": 32 },
    "keyLabels": {
      "type": "array",
      "items": { "type": "string", "minLength": 1, "maxLength": 64 },
      "maxItems": 32
    },
    "regionLabels": {
      "type": "array",
      "items": { "type": "string", "minLength": 1, "maxLength": 64 },
      "maxItems": 32
    },
    "activeIndex": { "type": "integer", "minimum": 0, "maximum": 31 },
    "atMs": { "type": "integer", "minimum": 0 }
  },
  "allOf": [
    {
      "if": { "properties": { "primaryHex": { "type": "null" } } },
      "then": {
        "properties": {
          "keyCount": { "const": 0 }
        }
      }
    },
    {
      "if": { "properties": { "primaryHex": { "type": "string" } } },
      "then": {
        "properties": {
          "keyCount": { "minimum": 1 }
        }
      }
    }
  ],
  "examples": [
    {
      "role": "seeder",
      "protocol": "bare-os-v1",
      "primaryHex": "1111111111111111111111111111111111111111111111111111111111111111",
      "failoverHexes": [
        "2222222222222222222222222222222222222222222222222222222222222222",
        "3333333333333333333333333333333333333333333333333333333333333333"
      ],
      "keyCount": 3,
      "keyLabels": ["primary", "failover-a", "failover-b"],
      "regionLabels": ["primary", "failover-a", "failover-b"],
      "activeIndex": 0,
      "atMs": 1745715600000
    }
  ]
}