{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "$id": "https://raw.githubusercontent.com/dchandan/stac-extension-cmip6/v1.0.0/json-schema/schema.json#",
  "title": "CMIP6 Extension",
  "description": "STAC CMIP6 Extension for STAC Items and STAC Collections.",
  "oneOf": [
    {
      "$comment": "This is the schema for STAC Items. Remove this object if this extension only applies to Collections.",
      "allOf": [
        {
          "$ref": "#/definitions/stac_extensions"
        },
        {
          "type": "object",
          "required": [
            "type",
            "properties",
            "assets"
          ],
          "properties": {
            "type": {
              "const": "Feature"
            },
            "properties": {
              "allOf": [
                {
                  "$comment": "Require fields here for Item Properties.",
                  "required": [
                    "cmip6:Conventions",
                    "cmip6:activity_id",
                    "cmip6:data_specs_version",
                    "cmip6:experiment",
                    "cmip6:experiment_id",
                    "cmip6:forcing_index",
                    "cmip6:frequency",
                    "cmip6:further_info_url",
                    "cmip6:grid",
                    "cmip6:grid_label",
                    "cmip6:initialization_index",
                    "cmip6:institution",
                    "cmip6:institution_id",
                    "cmip6:license",
                    "cmip6:mip_era",
                    "cmip6:nominal_resolution",
                    "cmip6:physics_index",
                    "cmip6:product",
                    "cmip6:realization_index",
                    "cmip6:realm",
                    "cmip6:source",
                    "cmip6:source_id",
                    "cmip6:source_type",
                    "cmip6:sub_experiment",
                    "cmip6:sub_experiment_id",
                    "cmip6:table_id",
                    "cmip6:variant_label"
                  ]
                },
                {
                  "$ref": "#/definitions/fields"
                }
              ]
            },
            "assets": {
              "$comment": "This validates the fields in Item Assets, but does not require them.",
              "type": "object",
              "additionalProperties": {
                "$ref": "#/definitions/fields"
              }
            }
          }
        }
      ]
    },
    {
      "$comment": "This is the schema for STAC Collections.",
      "type": "object",
      "allOf": [
        {
          "required": [
            "type"
          ],
          "properties": {
            "type": {
              "const": "Collection"
            }
          }
        },
        {
          "$ref": "#/definitions/stac_extensions"
        }
      ],
      "anyOf": [
        {
          "$comment": "This is the schema for the top-level fields in a Collection. Remove this if this extension does not define top-level fields for Collections.",
          "allOf": [
            {
              "$comment": "Require fields here for Collections (top-level).",
              "required": []
            },
            {
              "$ref": "#/definitions/fields"
            }
          ]
        },
        {
          "$comment": "This validates the fields in Collection Assets, but does not require them.",
          "required": [
            "assets"
          ],
          "properties": {
            "assets": {
              "type": "object",
              "not": {
                "additionalProperties": {
                  "not": {
                    "allOf": [
                      {
                        "$ref": "#/definitions/require_any_field"
                      },
                      {
                        "$ref": "#/definitions/fields"
                      }
                    ]
                  }
                }
              }
            }
          }
        },
        {
          "$comment": "This is the schema for the fields in Item Asset Definitions. It doesn't require any fields.",
          "required": [
            "item_assets"
          ],
          "properties": {
            "item_assets": {
              "type": "object",
              "not": {
                "additionalProperties": {
                  "not": {
                    "allOf": [
                      {
                        "$ref": "#/definitions/require_any_field"
                      },
                      {
                        "$ref": "#/definitions/fields"
                      }
                    ]
                  }
                }
              }
            }
          }
        },
        {
          "$comment": "This is the schema for the fields in Summaries. By default, only checks the existance of the properties, but not the schema of the summaries.",
          "required": [
            "summaries"
          ],
          "properties": {
            "summaries": {
              "$ref": "#/definitions/require_any_field"
            }
          }
        }
      ]
    }
  ],
  "definitions": {
    "stac_extensions": {
      "type": "object",
      "required": [
        "stac_extensions"
      ],
      "properties": {
        "stac_extensions": {
          "type": "array",
          "contains": {
            "const": "https://raw.githubusercontent.com/dchandan/stac-extension-cmip6/v1.0.0/json-schema/schema.json"
          }
        }
      }
    },
    "require_any_field": {
      "$comment": "Please list all fields here so that we can force the existence of one of them in other parts of the schemas.",
      "anyOf": [
                    {"required": ["cmip6:Conventions"]},
                    {"required": ["cmip6:activity_id"]},
                    {"required": ["cmip6:data_specs_version"]},
                    {"required": ["cmip6:experiment"]},
                    {"required": ["cmip6:experiment_id"]},
                    {"required": ["cmip6:forcing_index"]},
                    {"required": ["cmip6:frequency"]},
                    {"required": ["cmip6:further_info_url"]},
                    {"required": ["cmip6:grid"]},
                    {"required": ["cmip6:grid_label"]},
                    {"required": ["cmip6:initialization_index"]},
                    {"required": ["cmip6:institution"]},
                    {"required": ["cmip6:institution_id"]},
                    {"required": ["cmip6:license"]},
                    {"required": ["cmip6:mip_era"]},
                    {"required": ["cmip6:nominal_resolution"]},
                    {"required": ["cmip6:physics_index"]},
                    {"required": ["cmip6:product"]},
                    {"required": ["cmip6:realization_index"]},
                    {"required": ["cmip6:realm"]},
                    {"required": ["cmip6:source"]},
                    {"required": ["cmip6:source_id"]},
                    {"required": ["cmip6:source_type"]},
                    {"required": ["cmip6:sub_experiment"]},
                    {"required": ["cmip6:sub_experiment_id"]},
                    {"required": ["cmip6:table_id"]},
                    {"required": ["cmip6:variant_label"]}
      ]
    },
    "fields": {
      "$comment": "Add your new fields here. Don't require them here, do that above in the corresponding schema.",
      "type": "object",
      "properties": {
        "cmip6:Conventions": {"type": "string"},
        "cmip6:activity_id": {"type": "string"},
        "cmip6:data_specs_version": {"type": "string"},
        "cmip6:experiment": {"type": "string"},
        "cmip6:experiment_id": {"type": "string"},
        "cmip6:forcing_index": {"type": "number"},
        "cmip6:frequency": {"type": "string"},
        "cmip6:further_info_url": {"type": "string"},
        "cmip6:grid": {"type": "string"},
        "cmip6:grid_label": {"type": "string"},
        "cmip6:initialization_index": {"type": "number"},
        "cmip6:institution": {"type": "string"},
        "cmip6:institution_id": {"type": "string"},
        "cmip6:license": {"type": "string"},
        "cmip6:mip_era": {"type": "string"},
        "cmip6:nominal_resolution": {"type": "string"},
        "cmip6:physics_index": {"type": "number"},
        "cmip6:product": {"type": "string"},
        "cmip6:realization_index": {"type": "number"},
        "cmip6:realm": {"type": "array", "items": {"type": "string"}},
        "cmip6:source": {"type": "string"},
        "cmip6:source_id": {"type": "string"},
        "cmip6:source_type": {"type": "array", "items": {"type": "string"}},
        "cmip6:sub_experiment": {"type": "string"},
        "cmip6:sub_experiment_id": {"type": "string"},
        "cmip6:table_id": {"type": "string"},
        "cmip6:variant_label": {"type": "string"},
        "cmip6:creation_date": {"type": "string"},
        "cmip6:tracking_id": {"type": "string"},
        "cmip6:variable_id": {"type": "string"},
        "cmip6:version": {"type": "string"}
      },
      "patternProperties": {
        "^(?!cmip6:)": {}
      },
      "additionalProperties": false
    }
  }
}