{
  "$schema"                 : "http://json-schema.org/draft-04/schema#",
  "id"                      : "http://schemas.elite-markets.net/eddn/commodity/2#",
  "type"                    : "object",
  "additionalProperties"    : false,
  "required"                : [ "$schemaRef", "header", "message" ],
  "properties"              : {
    "$schemaRef"    : { "type": "string" },
    
    "header"        : {
      "type"                    : "object",
      "additionalProperties"    : true,
      "required": [ "uploaderID", "softwareName", "softwareVersion" ],
      "properties"  : {
        "uploaderID"        : { "type": "string" },
        "softwareName"      : { "type": "string" },
        "softwareVersion"   : { "type": "string" },
        "gatewayTimestamp"  : {
          "type": "string",
          "format": "date-time",
          "description": "Timestamp upon receipt at the gateway. If present, this property will be overwritten by the gateway; submitters are not intended to populate this property."
        }
      }
    },
    
    "message": {
      "type": "object",
      "additionalProperties": false,
      "required": [ "systemName", "stationName", "timestamp", "commodities" ],
      "properties": {
        "systemName": {
          "type"        : "string",
          "minLength"   : 1
        },
        "stationName": {
          "type"        : "string",
          "minLength"   : 1
        },
        "timestamp": {
          "type"        : "string",
          "format"      : "date-time"
        },
        "commodities": {
          "type"        : "array",
          "minItems"    : 1,
          "items"       : {
            "oneOf": [
              {
                "type"                  : "object",
                "additionalProperties"  : false,
                "required"              : [ "name", "buyPrice", "supply", "sellPrice", "demand" ],
                "properties"            : {
                  "name": {
                    "type"        : "string",
                    "minLength"   : 1
                  },
                  "buyPrice": {
                    "type": "integer",
                    "description": "Price to buy from the market"
                  },
                  "supply": {
                    "type": "integer"
                  },
                  "supplyLevel": {
                    "$ref": "#/definitions/levelType"
                  },
                  "sellPrice": {
                    "type": "integer",
                    "description": "Price to sell to the market"
                  },
                  "demand": {
                    "type": "integer"
                  },
                  "demandLevel": {
                    "$ref": "#/definitions/levelType"
                  }   
                }
              }
            ]   
          }
        }
      }
    }
  },
  
  "definitions" : {
    "levelType" : {
      "enum": ["Low", "Med", "High"]
    }
  }
}