<xs:schema attributeFormDefault="qualified" elementFormDefault="qualified"  xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:dwd="https://opendata.dwd.de/weather/lib/pointforecast_dwd_extension_V1_0.xsd" targetNamespace="https://opendata.dwd.de/weather/lib/pointforecast_dwd_extension_V1_0.xsd">
  <xs:element name="ProductDefinition" >
    <xs:complexType>
      <xs:sequence>


        <xs:element name="Issuer" type="xs:string" minOccurs="1" maxOccurs="1" /> <!-- Responsible issuer for this product --> 


        <xs:element name="ProductID" minOccurs="1" maxOccurs="1" >
          <xs:annotation>
            <xs:documentation>Unique identification tag for this product, indicating the meteorological application and perhaps also the data, that was utilized for generation of this product.</xs:documentation>
          </xs:annotation>
	      <xs:simpleType>
	        <xs:restriction base="xs:string">
	          <xs:enumeration value="EZ_MOS"/> <!-- Model Output Statistics (MOS) point forecasts based on EZMW NWP-Model  -->
	          <xs:enumeration value="ICON_MOS"/> <!-- MOS point forecasts based on ICON NWP-Model  -->
	          <xs:enumeration value="MOSMIX"/> <!-- MOS point forecasts based on statistically optimized combination of EZ_MOS and ICON_MOS forecasts -->
	          <xs:enumeration value="COSMO_DE_EPS_EMOS"/> <!-- Ensemble MOS point forecasts based on COSMO-DE EPS NWP --> 		  
	          <xs:enumeration value="MODELMIX"/> <!-- Ensemble MOS point forecasts based on various EPS NWP single MOS forecasts --> 	
              <xs:enumeration value="GPTMOS"/> <!-- MOS point forecasts based on statistically optimized combination of EZ_MOS and ICON_MOS based forecasts for gas consumption-->			  
	          <xs:enumeration value="ICON_DMO"/> <!-- Point forecasts based on Direct Model Output from ICON13 - Replacement for Files o_gdmo* -->
	          <xs:enumeration value="ICON_NEST_DMO"/> <!-- Point forecasts based on Direct Model Output from ICON6 Nest - Replacement for Files o_ldmo* -->
	        </xs:restriction>
	      </xs:simpleType>
        </xs:element>


        <xs:element name="GeneratingProcess" type="xs:string" minOccurs="1" maxOccurs="1" >
          <xs:annotation>
            <xs:documentation>Detailed information about the meteorological application, that was used for generating this product</xs:documentation>
          </xs:annotation>
        </xs:element>


        <xs:element name="IssueTime" minOccurs="1" maxOccurs="1"  type="xs:dateTime">
          <xs:annotation>
            <xs:documentation>Modelrun or issue time for this product. The timepoint, at which the meteorological application was executed to generate this product.</xs:documentation>
          </xs:annotation>
        </xs:element>


	<xs:element name="ReferencedModel" minOccurs="1" maxOccurs="1" >
          <xs:annotation>
            <xs:documentation>If the meteorological application responsible for this product used NWP-Modeldata, it shall list its utilized NWP-Models with their respective Modelruns. </xs:documentation>
          </xs:annotation>
          <xs:complexType>
            <xs:sequence>
              <xs:element name="Model" maxOccurs="unbounded" minOccurs="0">
		<xs:complexType>
		  <xs:attribute type="xs:string" name="name" use="required"/>
		  <xs:attribute type="xs:dateTime" name="referenceTime" use="required"/>
		</xs:complexType>
	      </xs:element>
	    </xs:sequence>
	  </xs:complexType>
	</xs:element>
		
        <xs:element name="ForecastTimeSteps" minOccurs="1" maxOccurs="1" >
          <xs:annotation>
            <xs:documentation>Forecast Timesteps contained in this product</xs:documentation>
          </xs:annotation>
          <xs:complexType>
            <xs:sequence>
              <xs:element name="TimeStep" type="xs:dateTime" maxOccurs="unbounded" minOccurs="0" />
            </xs:sequence>
          </xs:complexType>
        </xs:element>


        <xs:element name="FormatCfg">
          <xs:complexType>
            <xs:sequence>
              <xs:element type="dwd:UndefChar" name="DefaultUndefSign" default="-">
                <xs:annotation>
                  <xs:documentation>this is the definition of the "classic" Character for an undefined value within the data</xs:documentation>
                </xs:annotation>
              </xs:element>
            </xs:sequence>
          </xs:complexType>
        </xs:element>


	<!-- Descriptive-Reference to MetElements contained in this Forecast-Product -->
 	<xs:element name="MetElementDefinition" type="xs:anyURI" default="https://opendata.dwd.de/weather/lib/MetElementDefinition.xml" />
	
     </xs:sequence>
    </xs:complexType>
  </xs:element> <!-- END Product-Definition -->


  <xs:simpleType name="UndefChar">
    <xs:restriction base="xs:string">
      <xs:length fixed="true" value="1" />
    </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="floatWithNewUndefSign">
    <xs:union>
      <xs:simpleType>
        <xs:restriction base="xs:float"/>
      </xs:simpleType>
      <xs:simpleType>
        <xs:restriction base="dwd:UndefChar"/>
      </xs:simpleType>
    </xs:union>
  </xs:simpleType>
  

  <xs:simpleType name="floatList" >
    <xs:list itemType="dwd:floatWithNewUndefSign" />
  </xs:simpleType>
    
  <!-- This is the representation of a forecast for all represented Timesteps for one meteorological Element -->
  <xs:element name="Forecast">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="value">
          <xs:complexType>
            <xs:simpleContent>
              <xs:extension base="dwd:floatList" />
            </xs:simpleContent>
          </xs:complexType>
		  
          <xs:key name="UndefCfgKey">                       <!-- Undef-Sign used in Forecast-Data Values shall match the defined Undef-Sign -->
           <xs:selector xpath="FormatCfg" />
           <xs:field xpath="DefaultUndefSign" />
          </xs:key>

          <xs:keyref name="UndefCfgRef" refer="dwd:UndefCfgKey">
           <xs:selector xpath="dwd:floatList" />
           <xs:field xpath="dwd:UndefChar" />
          </xs:keyref>
  	    
		</xs:element>
      </xs:sequence>
      <xs:attribute name="elementName" type="xs:string" /> <!-- Element-Name must be matched in referenced MetElementDefinition -->
    </xs:complexType>
  </xs:element>

</xs:schema>