rules:
  # INFO / METADATA
  info-title-required:
    description: API title must be present and include "USGS".
    severity: error
    given: $.info.title
    then:
      function: truthy

  info-description-min-length:
    description: API description must be at least 50 characters.
    severity: warn
    given: $.info
    then:
      field: description
      function: minLength
      functionOptions:
        min: 50

  info-version-required:
    description: API version must be specified.
    severity: error
    given: $.info
    then:
      field: version
      function: truthy

  info-contact-required:
    description: Contact information should be present.
    severity: warn
    given: $.info
    then:
      field: contact
      function: truthy

  info-license-required:
    description: License information should be present for government APIs.
    severity: info
    given: $.info
    then:
      field: license
      function: truthy

  # OPENAPI VERSION
  openapi-version-3:
    description: USGS API specs must use OpenAPI 3.0.x.
    severity: warn
    given: $
    then:
      field: openapi
      function: pattern
      functionOptions:
        match: "^3\\.0\\."

  # SERVERS
  servers-defined:
    description: At least one server URL must be defined.
    severity: error
    given: $
    then:
      field: servers
      function: truthy

  servers-https:
    description: All server URLs must use HTTPS.
    severity: error
    given: $.servers[*].url
    then:
      function: pattern
      functionOptions:
        match: "^https://"

  servers-usgs-domain:
    description: Server URLs should reference usgs.gov domains.
    severity: info
    given: $.servers[*].url
    then:
      function: pattern
      functionOptions:
        match: "usgs\\.gov"

  # PATHS — NAMING CONVENTIONS
  paths-kebab-case:
    description: Path segments must use kebab-case.
    severity: warn
    given: $.paths[*]~
    then:
      function: pattern
      functionOptions:
        match: "^(/[a-z0-9{}_.-]*)+$"

  paths-no-trailing-slash:
    description: Paths should not end with a trailing slash (except root).
    severity: info
    given: $.paths[*]~
    then:
      function: pattern
      functionOptions:
        notMatch: ".+/$"

  # OPERATIONS
  operation-summary-required:
    description: All operations must have a summary.
    severity: error
    given: $.paths[*][get,post,put,patch,delete]
    then:
      field: summary
      function: truthy

  operation-summary-prefix:
    description: Operation summaries should start with "USGS".
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].summary
    then:
      function: pattern
      functionOptions:
        match: "^USGS"

  operation-description-required:
    description: All operations should have a description.
    severity: warn
    given: $.paths[*][get,post,put,patch,delete]
    then:
      field: description
      function: truthy

  operation-id-required:
    description: All operations must have an operationId.
    severity: error
    given: $.paths[*][get,post,put,patch,delete]
    then:
      field: operationId
      function: truthy

  operation-id-camel-case:
    description: OperationIds should use camelCase.
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].operationId
    then:
      function: pattern
      functionOptions:
        match: "^[a-z][a-zA-Z0-9]*$"

  operation-tags-required:
    description: All operations must have at least one tag.
    severity: warn
    given: $.paths[*][get,post,put,patch,delete]
    then:
      field: tags
      function: truthy

  # TAGS
  tags-global-defined:
    description: Global tags array should be defined with descriptions.
    severity: info
    given: $
    then:
      field: tags
      function: truthy

  # PARAMETERS
  parameter-description-required:
    description: All parameters must have a description.
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].parameters[*]
    then:
      field: description
      function: truthy

  parameter-schema-required:
    description: All parameters must define a schema.
    severity: error
    given: $.paths[*][get,post,put,patch,delete].parameters[*]
    then:
      field: schema
      function: truthy

  parameter-format-lowercase:
    description: Format parameter values should use lowercase identifiers.
    severity: info
    given: $.paths[*][get,post,put,patch,delete].parameters[?(@.name == 'f')].schema.enum[*]
    then:
      function: pattern
      functionOptions:
        match: "^[a-z]+$"

  # RESPONSES
  response-success-required:
    description: All operations must define a 200 success response.
    severity: error
    given: $.paths[*][get,post,put,patch,delete].responses
    then:
      function: schema
      functionOptions:
        schema:
          type: object
          required:
            - "200"

  response-400-defined:
    description: Operations should define a 400 error response.
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].responses
    then:
      function: schema
      functionOptions:
        schema:
          type: object
          required:
            - "400"

  response-403-defined:
    description: Authenticated operations should define a 403 error response.
    severity: info
    given: $.paths[*][get,post].responses
    then:
      function: schema
      functionOptions:
        schema:
          type: object
          required:
            - "403"

  response-description-required:
    description: All response definitions must have descriptions.
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].responses[*]
    then:
      field: description
      function: truthy

  # SCHEMAS — PROPERTY NAMING
  schema-description-required:
    description: Component schemas should have descriptions.
    severity: warn
    given: $.components.schemas[*]
    then:
      field: description
      function: truthy

  schema-geojson-type-documented:
    description: GeoJSON Feature and FeatureCollection schemas should document the 'type' property.
    severity: info
    given: $.components.schemas[?(@.title =~ /Feature|Collection/)].properties
    then:
      function: schema
      functionOptions:
        schema:
          type: object
          required:
            - type

  # SECURITY
  security-scheme-defined:
    description: API key security schemes should be defined in components.
    severity: warn
    given: $.components.securitySchemes
    then:
      function: truthy

  security-api-key-documented:
    description: API key security scheme should describe how to obtain the key.
    severity: info
    given: $.components.securitySchemes[*]
    then:
      field: description
      function: truthy

  # HTTP METHOD CONVENTIONS
  get-no-request-body:
    description: GET operations must not have a request body.
    severity: error
    given: $.paths[*].get
    then:
      field: requestBody
      function: falsy

  # OGC/USGS SPECIFIC
  usgs-ogc-format-parameter:
    description: OGC API endpoints should support the 'f' format parameter.
    severity: info
    given: $.paths[*].get.parameters[*].name
    then:
      function: schema
      functionOptions:
        schema:
          type: string

  usgs-rate-limit-documented:
    description: APIs with API key auth should document 429 responses.
    severity: info
    given: $.paths[*][get,post].responses
    then:
      function: schema
      functionOptions:
        schema:
          type: object
          required:
            - "429"

  # GENERAL QUALITY
  no-empty-descriptions:
    description: Descriptions should not be empty.
    severity: warn
    given: $..description
    then:
      function: pattern
      functionOptions:
        match: ".{1,}"