$schema: https://json-schema.org/draft/2020-12/schema
description: A structured topology dataset with named arrays for each topological
  dimension. Points carry explicit coordinates; all higher-order features (edges,
  faces, shells, solids) use null geometry with topology defined via references or
  directed_references. Each array is restricted to its corresponding building block
  schema.
$defs:
  PointFeatures:
    $anchor: PointFeatures
    type: array
    items:
      properties:
        geometry:
          type: object
          required:
          - type
          - coordinates
          properties:
            type:
              type: string
              const: Point
            coordinates:
              type: array
              minItems: 2
      required:
      - geometry
  EdgeFeatures:
    $anchor: EdgeFeatures
    type: array
    items:
      allOf:
      - $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-line/schema.yaml
      - properties:
          topology:
            properties:
              references:
                minItems: 2
                maxItems: 2
type: object
required:
- type
properties:
  type:
    type: string
    const: FeatureCollection
  metadata:
    type: object
    description: Optional dataset metadata (units, coordinate precision, source info,
      etc.)
    additionalProperties: true
  points:
    type: array
    description: Point features providing base coordinate geometry for the topology
    items:
      oneOf:
      - $ref: '#PointFeatures'
      - allOf:
        - $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-feature-collection/schema.yaml#FeatureCollectionOptions
        - properties:
            features:
              $ref: '#PointFeatures'
    x-jsonld-id: https://purl.org/geojson/topo#points
    x-jsonld-container: '@list'
  edges:
    oneOf:
    - $ref: '#EdgeFeatures'
    - type: array
      description: Edge (LineString) features referencing two point nodes via topology.references.
      items:
        allOf:
        - $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-feature-collection/schema.yaml#FeatureCollectionOptions
        - properties:
            features:
              $ref: '#EdgeFeatures'
    x-jsonld-id: https://purl.org/geojson/topo#edges
    x-jsonld-container: '@list'
  rings:
    type: array
    description: Ring features whose boundary segments reference edges via directed_references.
      geometry is null.
    items:
      oneOf:
      - $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-ring/schema.yaml
      - allOf:
        - $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-feature-collection/schema.yaml#FeatureCollectionOptions
        - properties:
            features:
              type: array
              items:
                $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-ring/schema.yaml
  faces:
    type: array
    description: Face features whose boundary rings reference edges via directed_references.
      geometry is null.
    items:
      oneOf:
      - $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-face/schema.yaml
      - allOf:
        - $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-feature-collection/schema.yaml#FeatureCollectionOptions
        - properties:
            features:
              type: array
              items:
                $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-face/schema.yaml
  shells:
    type: array
    description: Shell features referencing faces via directed_references. geometry
      is null.
    items:
      oneOf:
      - $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-shell/schema.yaml
      - allOf:
        - $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-feature-collection/schema.yaml#FeatureCollectionOptions
        - properties:
            features:
              type: array
              items:
                $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-shell/schema.yaml
  solids:
    type: array
    description: Solid features whose shells reference faces via directed_references.
      geometry is null.
    items:
      oneOf:
      - $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-solid/schema.yaml
      - allOf:
        - $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-feature-collection/schema.yaml#FeatureCollectionOptions
        - properties:
            features:
              type: array
              items:
                $ref: https://ogcincubator.github.io/topo-feature/build/annotated/geo/topo/features/topo-solid/schema.yaml
    x-jsonld-id: https://purl.org/geojson/topo#solids
    x-jsonld-container: '@list'
x-jsonld-prefixes:
  topo: https://purl.org/geojson/topo#