{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "Verifiable Attestation",
  "description": "The schema defines a generic structure for any Verifiable Credentials according to the VCDM v1.1",
  "type": "object",
  "properties": {
    "@context": {
      "description": "Semantic context for the issued credential. First element MUST be https://www.w3.org/2018/credentials/v1",
      "type": "array",
      "items": {
        "type": "string",
        "format": "uri"
      },
      "contains": {
        "const": "https://www.w3.org/2018/credentials/v1"
      },
      "minItems": 1,
      "uniqueItems": true
    },
    "id": {
      "description": "Globally unique identifier for the issued credential",
      "type": "string",
      "format": "uri"
    },
    "type": {
      "description": "Full type chain, used to identify the credential base types",
      "type": "array",
      "items": {
        "type": "string"
      },
      "contains": {
        "type": "string",
        "const": "VerifiableAttestation"
      },
      "uniqueItems": true
    },
    "issuer": {
      "description": "Defines a property for expressing the issuer of a Verifiable Credential",
      "oneOf": [
        {
          "description": "DID of the credential issuer",
          "type": "string",
          "format": "uri"
        },
        {
          "type": "object",
          "required": ["id"],
          "properties": {
            "id": {
              "description": "DID of the credential issuer",
              "type": "string",
              "format": "uri"
            }
          }
        }
      ]
    },
    "issuanceDate": {
      "description": "Defines the date and time, when the issued credential becomes valid",
      "type": "string",
      "format": "date-time"
    },
    "issued": {
      "description": "Defines when the issued credential was issued",
      "type": "string",
      "format": "date-time"
    },
    "validFrom": {
      "description": "Defines the date and time, when the issued credential becomes valid",
      "type": "string",
      "format": "date-time"
    },
    "validUntil": {
      "description": "Defines the date and time, when the issued credential expires",
      "type": "string",
      "format": "date-time"
    },
    "expirationDate": {
      "description": "Defines the date and time, when the issued credential expires",
      "type": "string",
      "format": "date-time"
    },
    "credentialSubject": {
      "description": "Defines information about the subject that is defined by the type chain",
      "anyOf": [
        {
          "$ref": "#/$defs/credentialSubject"
        },
        {
          "type": "array",
          "items": {
            "$ref": "#/$defs/credentialSubject"
          }
        }
      ]
    },
    "credentialStatus": {
      "description": "Defines suspension and/or revocation details for the issued credential. Further redefined by the type extension",
      "anyOf": [
        {
          "$ref": "#/$defs/credentialStatus"
        },
        {
          "type": "array",
          "items": {
            "$ref": "#/$defs/credentialStatus"
          }
        }
      ]
    },
    "credentialSchema": {
      "description": "One or more schemas that validate the Verifiable Credential.",
      "anyOf": [
        {
          "$ref": "#/$defs/credentialSchema"
        },
        {
          "type": "array",
          "items": {
            "$ref": "#/$defs/credentialSchema"
          }
        }
      ]
    },
    "termsOfUse": {
      "description": "Contains the terms under which the issued credential was issued",
      "anyOf": [
        {
          "$ref": "#/$defs/termsOfUse"
        },
        {
          "type": "array",
          "items": {
            "$ref": "#/$defs/termsOfUse"
          }
        }
      ]
    },
    "evidence": {
      "description": "Contains the optional evidence used to issue this credential",
      "anyOf": [
        {
          "$ref": "#/$defs/evidence"
        },
        {
          "type": "array",
          "items": {
            "$ref": "#/$defs/evidence"
          }
        }
      ]
    }
  },
  "required": [
    "@context",
    "id",
    "type",
    "issuer",
    "credentialSubject"
  ],
  "$defs": {
    "credentialSubject": {
      "description": "Defines information about the subject that is defined by the type chain",
      "type": "object",
      "properties": {
        "id": {
          "description": "Defines the DID of the subject that is described by the issued credential",
          "type": "string",
          "format": "uri"
        }
      }
    },
    "credentialStatus": {
      "description": "Defines suspension and/or revocation details for the issued credential. Further redefined by the type extension",
      "type": "object",
      "properties": {
        "id": {
          "description": "Exact identity for the credential status",
          "type": "string",
          "format": "uri"
        },
        "type": {
          "description": "Defines the revocation type extension",
          "type": "string"
        }
      },
      "required": ["id", "type"]
    },
    "credentialSchema": {
      "description": "Contains information about the credential schema on which the issued credential is based",
      "type": "object",
      "properties": {
        "id": {
          "description": "References the credential schema stored on the Trusted Schemas Registry (TSR) on which the Verifiable Authorisation is based on",
          "type": "string",
          "format": "uri"
        },
        "type": {
          "description": "Defines credential schema type",
          "type": "string"
        }
      },
      "required": ["id", "type"]
    },
    "termsOfUse": {
      "description": "Contains the terms under which the issued credential was issued",
      "type": "object",
      "properties": {
        "id": {
          "description": "Contains a URL that points to where more information about this instance of terms of use can be found.",
          "type": "string"
        },
        "type": {
          "description": "Defines the type extension",
          "type": "string"
        }
      },
      "required": ["type"]
    },
    "evidence": {
      "type": "object",
      "properties": {
        "id": {
          "description": "If present, it SHOULD contain a URL that points to where more information about this instance of evidence can be found.",
          "type": "string"
        },
        "type": {
          "anyOf": [
            {
              "description": "Defines the evidence type extension",
              "type": "string"
            },
            {
              "description": "Defines the evidence type extension",
              "type": "array",
              "items": {
                "type": "string"
              }
            }
          ]
        }
      },
      "required": ["type"]
    }
  }
}