{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://receiptprotocol.com/open-receipt/v0.1/event.schema.json",
  "title": "Open Receipt event v0.1",
  "description": "A portable, signed evidence event. This schema does not describe a wallet, payment rail, routing engine, remedy system, or guarantee.",
  "type": "object",
  "additionalProperties": false,
  "required": [
    "spec_version",
    "event_id",
    "event_type",
    "issuer",
    "issued_at",
    "transaction_id",
    "quote_id",
    "commercial_facts",
    "evidence",
    "provenance",
    "assurance",
    "parent_event_hashes",
    "signing_key_id",
    "signature"
  ],
  "properties": {
    "spec_version": { "const": "0.1" },
    "event_id": { "type": "string", "minLength": 1, "maxLength": 256 },
    "event_type": {
      "enum": [
        "quote.issued",
        "authorization.granted",
        "execution.attempted",
        "validation.completed",
        "settlement.completed",
        "reversal.issued"
      ]
    },
    "issuer": { "$ref": "#/$defs/issuer" },
    "issued_at": { "type": "string", "format": "date-time" },
    "transaction_id": { "type": "string", "minLength": 1, "maxLength": 256 },
    "quote_id": { "type": ["string", "null"], "maxLength": 256 },
    "commercial_facts": {
      "type": "object",
      "description": "Commercial facts such as currency, authorized maximum, final charge, and public seller identity.",
      "additionalProperties": true
    },
    "evidence": {
      "type": "object",
      "description": "Digests and safe evidence statements. Raw provider credentials and private payloads do not belong here.",
      "additionalProperties": true
    },
    "provenance": {
      "type": "object",
      "description": "Public execution provenance and configuration digests.",
      "additionalProperties": true
    },
    "assurance": { "enum": ["delivered", "validated"] },
    "parent_event_hashes": {
      "type": "array",
      "uniqueItems": true,
      "items": { "type": "string", "pattern": "^sha256:[a-f0-9]{64}$" }
    },
    "signing_key_id": { "type": "string", "minLength": 1, "maxLength": 256 },
    "signature": {
      "type": "string",
      "description": "Detached compact JWS: BASE64URL(protected)..BASE64URL(signature).",
      "pattern": "^[A-Za-z0-9_-]+\\.\\.[A-Za-z0-9_-]+$"
    }
  },
  "$defs": {
    "issuer": {
      "type": "object",
      "additionalProperties": false,
      "required": ["id", "metadata_url"],
      "properties": {
        "id": { "type": "string", "format": "uri" },
        "name": { "type": "string", "maxLength": 200 },
        "metadata_url": { "type": "string", "format": "uri" },
        "verification_key": { "$ref": "#/$defs/publicKey" }
      }
    },
    "publicKey": {
      "type": "object",
      "additionalProperties": false,
      "required": ["kty", "crv", "x", "kid"],
      "properties": {
        "kty": { "const": "OKP" },
        "crv": { "const": "Ed25519" },
        "x": { "type": "string", "pattern": "^[A-Za-z0-9_-]{43}$" },
        "kid": { "type": "string", "minLength": 1 },
        "use": { "const": "sig" },
        "alg": { "const": "EdDSA" }
      }
    }
  }
}