<?xml version="1.0"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">

    <xsd:complexType name="time-layoutElementType">
        <xsd:sequence>
                        <xsd:element name="layout-key" type="layout-keyType" minOccurs="1" maxOccurs="1" /> 
                        <xsd:sequence minOccurs="1" maxOccurs="unbounded">
                            <xsd:element name="start-valid-time" type="start-valid-timeType" minOccurs="1" maxOccurs="unbounded" />
                            <xsd:element name="end-valid-time" type="xsd:dateTime" minOccurs="0" maxOccurs="unbounded" />
                        </xsd:sequence>
        </xsd:sequence>
        <xsd:attribute name="time-coordinate" type="time-coordinateType" use="required" />      
        <xsd:attribute name="summarization" type="summarizationType" use="optional" />
    </xsd:complexType>

    <xsd:simpleType name="time-coordinateType">
       <xsd:restriction base="xsd:string">
          <xsd:enumeration value="UTC" />
          <xsd:enumeration value="local" />
       </xsd:restriction>
    </xsd:simpleType>

    <xsd:complexType name="start-valid-timeType">
        <xsd:simpleContent>
            <xsd:extension base="xsd:dateTime">
                <xsd:attribute name="period-name" type="xsd:string" />
            </xsd:extension>
        </xsd:simpleContent>
    </xsd:complexType>

    <xsd:simpleType name="layout-keyType">
       <xsd:restriction base="xsd:string">
          <xsd:pattern value="k-p\d+[h|d|m|y]-n\d+-\d+" />
       </xsd:restriction>
    </xsd:simpleType>

</xsd:schema>
