<?xml version="1.0" encoding="UTF-8"?>
<!-- $Header: /home/cvsroot/w3c-xml-schema/user/examples/first-complex-types.xsd,v 1.1 2001/11/12 20:54:00 vdv Exp $ -->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">

  <xs:simpleType name="string255">
    <xs:restriction base="xs:token">
      <xs:maxLength value="255"/>
    </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="string32">
    <xs:restriction base="xs:token">
      <xs:maxLength value="32"/>
    </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="isbn">
    <xs:restriction base="xs:unsignedLong">
      <xs:totalDigits value="10"/>
      <xs:pattern value="\d{10}"/>
    </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="bookID">
    <xs:restriction base="xs:ID">
      <xs:pattern value="b\d{10}"/>
    </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="supportedLanguages">
    <xs:restriction base="xs:language">
      <xs:enumeration value="en"/>
      <xs:enumeration value="es"/>
    </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="date">
    <xs:restriction base="xs:date">
      <xs:pattern value="[^:Z]*"/>
    </xs:restriction>
  </xs:simpleType>

  <xs:element name="name" type="string32"/>
  <xs:element name="qualification" type="string255"/>
  <xs:element name="born" type="date"/>
  <xs:element name="dead" type="date"/>
  <xs:element name="isbn" type="isbn"/>
  
  <xs:attribute name="id" type="xs:ID"/>
  <xs:attribute name="available" type="xs:boolean"/>
  <xs:attribute name="lang" type="supportedLanguages"/>

  <xs:complexType name="elementWithID">
    <xs:attribute ref="id"/>
  </xs:complexType>

  <xs:complexType name="bookTmp">
    <xs:complexContent>
      <xs:extension base="elementWithID">
        <xs:sequence>
          <xs:element ref="isbn"/>
          <xs:element ref="title"/>
          <xs:element ref="author" minOccurs="0" maxOccurs="unbounded"/>
          <xs:element ref="character" minOccurs="0" maxOccurs="unbounded"/>
        </xs:sequence>
        <xs:attribute ref="available"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>
  
  <xs:complexType name="personType">
    <xs:complexContent>
      <xs:extension base="elementWithID">
        <xs:sequence>
          <xs:element ref="name"/>
          <xs:element ref="born"/>
          <xs:element ref="dead" minOccurs="0"/>
          <xs:element ref="qualification"  minOccurs="0"/>
        </xs:sequence>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>
    
  <xs:element name="title">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="string255">
          <xs:attribute ref="lang"/>
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  
  <xs:element name="library">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="book" maxOccurs="unbounded"/>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  
  <xs:element name="book">
    <xs:complexType>
      <xs:complexContent>
        <xs:restriction base="bookTmp">
          <xs:sequence>
            <xs:element ref="isbn"/>
            <xs:element ref="title"/>
            <xs:element ref="author" minOccurs="0" maxOccurs="unbounded"/>
            <xs:element ref="character" minOccurs="0" maxOccurs="unbounded"/>
          </xs:sequence>
          <xs:attribute name="id" type="bookID"/>
          <xs:attribute ref="available"/>
        </xs:restriction>
      </xs:complexContent>
    </xs:complexType>
  </xs:element>

  <xs:element name="author">
    <xs:complexType>
      <xs:complexContent>
        <xs:restriction base="personType">
          <xs:sequence>
            <xs:element ref="name"/>
            <xs:element ref="born"/>
            <xs:element ref="dead" minOccurs="0"/>
          </xs:sequence>
          <xs:attribute ref="id"/>
        </xs:restriction>
      </xs:complexContent>
    </xs:complexType>
  </xs:element>
  
  
  <xs:element name="character">
    <xs:complexType>
      <xs:complexContent>
        <xs:restriction base="personType">
          <xs:sequence>
            <xs:element ref="name"/>
            <xs:element ref="born"/>
            <xs:element ref="qualification"/>
          </xs:sequence>
          <xs:attribute ref="id"/>
        </xs:restriction>
      </xs:complexContent>
    </xs:complexType>
  </xs:element>
  
</xs:schema>