{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "$id": "https://stac-extensions.github.io/classification/v2.0.0/schema.json#",
  "title": "Classification Extension",
  "description": "STAC Classification Extension for STAC Items and STAC Collections.",
  "type": "object",
  "required": ["stac_extensions"],
  "properties": {
    "stac_extensions": {
      "type": "array",
      "contains": {
        "const": "https://stac-extensions.github.io/classification/v2.0.0/schema.json"
      }
    }
  },
  "oneOf": [
    {
      "$comment": "This is the schema for STAC Items.",
      "type": "object",
      "required": ["type", "properties", "assets"],
      "properties": {
        "type": {
          "const": "Feature"
        },
        "properties": {
          "$comment": "This validates the fields in Item Properties, but does not require them.",
          "allOf": [
            {
              "$ref": "#/definitions/fields"
            },
            {
              "$ref": "#/definitions/ml_model_output"
            }
          ]
        },
        "assets": {
          "$comment": "This validates the fields in Item Assets (including in Raster Band Objects), but does not require them.",
          "type": "object",
          "additionalProperties": {
            "allOf": [
              {
                "$ref": "#/definitions/fields"
              },
              {
                "$ref": "#/definitions/raster_bands"
              },
              {
                "$ref": "#/definitions/ml_model_output"
              }
            ]
          }
        }
      }
    },
    {
      "$comment": "This is the schema for STAC Collections.",
      "type": "object",
      "required": ["type"],
      "properties": {
        "type": {
          "const": "Collection"
        },
        "assets": {
          "$comment": "This validates the fields in Collection Assets, but does not require them.",
          "type": "object",
          "additionalProperties": {
            "allOf": [
              {
                "$ref": "#/definitions/fields"
              },
              {
                "$ref": "#/definitions/raster_bands"
              },
              {
                "$ref": "#/definitions/ml_model_output"
              }
            ]
          }
        },
        "item_assets": {
          "$comment": "This validates the fields in Item Asset Definitions, but does not require them.",
          "type": "object",
          "additionalProperties": {
            "allOf": [
              {
                "$ref": "#/definitions/fields"
              },
              {
                "$ref": "#/definitions/raster_bands"
              },
              {
                "$ref": "#/definitions/ml_model_output"
              }
            ]
          }
        },
        "summaries": {
          "$comment": "This validates the fields in Summaries, but does not require them.",
          "$ref": "#/definitions/fields"
        }
      }
    }
  ],
  "definitions": {
    "require_any_field": {
      "$comment": "Please list all fields here so that we can force the existance of one of them in other parts of the schemas.",
      "anyOf": [
        {
          "required": ["classification:bitfields"]
        },
        {
          "required": ["classification:classes"]
        }
      ]
    },
    "fields": {
      "$comment": "Add your new fields here. Don't require them here, do that above in the corresponding schema.",
      "type": "object",
      "properties": {
        "classification:bitfields": {
          "type": "array",
          "uniqueItems": true,
          "minItems": 1,
          "items": {
            "$ref": "#/definitions/bit_field_object"
          }
        },
        "classification:classes": {
          "type": "array",
          "uniqueItems": true,
          "minItems": 1,
          "items": {
            "$ref": "#/definitions/class_object"
          }
        }
      },
      "patternProperties": {
        "^(?!classification:)": {}
      },
      "additionalProperties": false
    },
    "class_object": {
      "$comment": "Object for storing classes",
      "type": "object",
      "required": ["value", "name"],
      "properties": {
        "value": {
          "type": "integer"
        },
        "description": {
          "type": "string"
        },
        "name": {
          "type": "string",
          "pattern": "^[0-9A-Za-z-_]+$"
        },
        "title": {
          "type": "string"
        },
        "color_hint": {
          "type": "string",
          "pattern": "^([0-9A-Fa-f]{6})$"
        },
        "nodata": {
          "type": "boolean"
        },
        "percentage": {
          "type": "number",
          "minimum": 0,
          "maximum": 100
        },
        "count": {
          "type": "integer",
          "minimum": 0
        }
      }
    },
    "bit_field_object": {
      "$comment": "Object for storing bit fields",
      "type": "object",
      "required": ["offset", "length", "classes"],
      "properties": {
        "offset": {
          "type": "integer",
          "minimum": 0
        },
        "length": {
          "type": "integer",
          "minimum": 1
        },
        "classes": {
          "type": "array",
          "uniqueItems": true,
          "minItems": 1,
          "items": {
            "$ref": "#/definitions/class_object"
          }
        },
        "roles": {
          "type": "array",
          "uniqueItems": true,
          "minItems": 1,
          "items": {
            "type": "string"
          }
        },
        "description": {
          "type": "string"
        },
        "name": {
          "type": "string",
          "pattern": "^[0-9A-Za-z-_]+$"
        }
      }
    },
    "raster_bands": {
      "$comment": "Classification fields on the Raster Extension raster:bands object",
      "type": "object",
      "properties": {
        "raster:bands": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/fields"
          }
        }
      }
    },
    "ml_model_output": {
      "$comment": "Classification fields on the MLM Extension mlm:output objects (https://crim-ca.github.io/mlm-extension/v1.0.0/schema.json).",
      "description": "Describes the classes embedded in the output of the ML model following inference.",
      "type": "object",
      "properties": {
        "mlm:output": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/fields"
          }
        }
      }
    }
  }
}