<?xml version="1.0" encoding="UTF-8"?>
<!--
 Copyright (c) 2000-2021 Ericsson Telecom AB
 All rights reserved. This program and the accompanying materials
 are made available under the terms of the Eclipse Public License v2.0
 which accompanies this distribution, and is available at
 https://www.eclipse.org/org/documents/epl-2.0/EPL-2.0.html

 Contributors:
  Balasko, Jeno
  Raduly, Csaba
-->
   <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
       targetNamespace="urn:ietf:params:xml:ns:pidf"
            xmlns:pidf="urn:ietf:params:xml:ns:pidf"
        elementFormDefault="qualified"
        attributeFormDefault="unqualified">

     <!-- This import brings in the XML language attribute xml:lang-->
     <xs:import namespace="http://www.w3.org/XML/1998/namespace"
       schemaLocation="xml.xsd"/>

     <xs:element name="presence" type="pidf:presence"/>

     <xs:complexType name="presence">
       <xs:sequence>
         <xs:element name="tuple" type="pidf:tuple" minOccurs="0"
            maxOccurs="unbounded"/>

         <xs:element name="note" type="pidf:note" minOccurs="0"
            maxOccurs="unbounded"/>
         <xs:any namespace="##other" processContents="lax" minOccurs="0"
            maxOccurs="unbounded"/>
       </xs:sequence>
       <xs:attribute name="entity" type="xs:anyURI" use="required"/>
     </xs:complexType>

     <xs:complexType name="tuple">
       <xs:sequence>
         <xs:element name="status" type="pidf:status"/>
         <xs:any namespace="##other" processContents="lax" minOccurs="0"
            maxOccurs="unbounded"/>
         <xs:element name="contact" type="pidf:contact" minOccurs="0"/>
         <xs:element name="note" type="pidf:note" minOccurs="0"
            maxOccurs="unbounded"/>
         <xs:element name="timestamp" type="xs:dateTime" minOccurs="0"/>
       </xs:sequence>
       <xs:attribute name="id" type="xs:ID" use="required"/>
     </xs:complexType>

     <xs:complexType name="status">
       <xs:sequence>
         <xs:element name="basic" type="pidf:basic" minOccurs="0"/>
         <xs:any namespace="##other" processContents="lax" minOccurs="0"
            maxOccurs="unbounded"/>
       </xs:sequence>
     </xs:complexType>
     <xs:simpleType name="basic">
       <xs:restriction base="xs:string">
         <xs:enumeration value="open"/>
         <xs:enumeration value="closed"/>
       </xs:restriction>
     </xs:simpleType>

     <xs:complexType name="contact">
       <xs:simpleContent>
         <xs:extension base="xs:anyURI">
           <xs:attribute name="priority" type="pidf:qvalue"/>
         </xs:extension>
       </xs:simpleContent>
     </xs:complexType>

     <xs:complexType name="note">
       <xs:simpleContent>
         <xs:extension base="xs:string">
           <xs:attribute ref="xml:lang"/>
         </xs:extension>

       </xs:simpleContent>
     </xs:complexType>

     <xs:simpleType name="qvalue">
       <xs:restriction base="xs:decimal">
         <xs:pattern value="0(.[0-9]{0,3})?"/>
         <xs:pattern value="1(.0{0,3})?"/>
       </xs:restriction>
     </xs:simpleType>

     <!-- Global Attributes -->
     <xs:attribute name="mustUnderstand" type="xs:boolean" default="0">
       <xs:annotation>
         <xs:documentation>
         This attribute may be used on any element within an optional
         PIDF extension to indicate that the corresponding element must
         be understood by the PIDF processor if the enclosing optional
         element is to be handled.
         </xs:documentation>
       </xs:annotation>
     </xs:attribute>
   </xs:schema>
