{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "$id": "https://local-loop-io.github.io/projects/loop-protocol/schemas/v0.2.0/handshake.schema.json",
  "title": "NodeHandshake",
  "description": "Federation handshake schema — LOOP v0.2.0",
  "oneOf": [
    {
      "$ref": "#/definitions/HandshakeRequest"
    },
    {
      "$ref": "#/definitions/HandshakeResponse"
    }
  ],
  "definitions": {
    "HandshakeRequest": {
      "type": "object",
      "required": [
        "@context",
        "@type",
        "schema_version",
        "node_id",
        "name",
        "endpoint",
        "capabilities",
        "timestamp"
      ],
      "properties": {
        "@context": {
          "type": "string",
          "enum": [
            "https://local-loop-io.github.io/projects/loop-protocol/contexts/loop-v0.1.1.jsonld",
            "https://local-loop-io.github.io/projects/loop-protocol/contexts/loop-v0.2.0.jsonld"
          ]
        },
        "@type": {
          "type": "string",
          "const": "NodeHandshake"
        },
        "schema_version": {
          "type": "string",
          "pattern": "^0\\.[1-9]\\d*\\.\\d+$"
        },
        "node_id": {
          "type": "string",
          "pattern": "^[a-z0-9\\-]+\\.loop$",
          "examples": [
            "munich.loop"
          ]
        },
        "name": {
          "type": "string",
          "minLength": 2,
          "maxLength": 120,
          "examples": [
            "DEMO Munich Node"
          ]
        },
        "endpoint": {
          "type": "string",
          "format": "uri",
          "pattern": "^https?://",
          "examples": [
            "https://demo-munich.loop/api"
          ]
        },
        "capabilities": {
          "type": "array",
          "minItems": 1,
          "items": {
            "type": "string"
          },
          "examples": [
            [
              "material-registry",
              "lab-relay"
            ]
          ]
        },
        "public_key": {
          "type": "string",
          "description": "Optional public key for lab validation",
          "examples": [
            "-----BEGIN PUBLIC KEY-----...-----END PUBLIC KEY-----"
          ]
        },
        "timestamp": {
          "type": "string",
          "format": "date-time"
        },
        "signature": {
          "type": "string",
          "description": "Optional lab-only signature placeholder"
        }
      },
      "additionalProperties": false
    },
    "HandshakeResponse": {
      "type": "object",
      "required": [
        "@context",
        "@type",
        "schema_version",
        "status",
        "peer_id",
        "capabilities",
        "received_at",
        "lab_only"
      ],
      "properties": {
        "@context": {
          "type": "string",
          "enum": [
            "https://local-loop-io.github.io/projects/loop-protocol/contexts/loop-v0.1.1.jsonld",
            "https://local-loop-io.github.io/projects/loop-protocol/contexts/loop-v0.2.0.jsonld"
          ]
        },
        "@type": {
          "type": "string",
          "const": "NodeHandshakeResponse"
        },
        "schema_version": {
          "type": "string",
          "pattern": "^0\\.[1-9]\\d*\\.\\d+$"
        },
        "status": {
          "type": "string",
          "enum": [
            "accepted",
            "rejected"
          ]
        },
        "peer_id": {
          "type": "string",
          "pattern": "^[a-z0-9\\-]+\\.loop$",
          "examples": [
            "lab-hub.loop"
          ]
        },
        "capabilities": {
          "type": "array",
          "minItems": 1,
          "items": {
            "type": "string"
          }
        },
        "received_at": {
          "type": "string",
          "format": "date-time"
        },
        "lab_only": {
          "type": "boolean",
          "const": true
        },
        "message": {
          "type": "string",
          "maxLength": 280
        }
      },
      "additionalProperties": false
    }
  }
}