<?xml version="1.0" encoding="UTF-8"?>
<!--
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
-->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
    <xs:complexType name="indexerType" mixed="true">
        <xs:annotation>
            <xs:documentation>
                Indexer declaration.
            </xs:documentation>
        </xs:annotation>
        <xs:sequence>
            <xs:choice minOccurs="0" maxOccurs="unbounded">
                <xs:element name="title" type="translatableType"/>
                <xs:element name="description" type="translatableType"/>
                <xs:element name="saveHandler" type="saveHandlerType"/>
                <xs:element name="structure" type="structureType"/>
                <xs:group ref="fieldset"/>
            </xs:choice>
            <xs:group ref="dependencies"/>
        </xs:sequence>
        <xs:attribute name="id" type="xs:string" use="required"/>
        <xs:attribute name="primary" type="nameType"/>
        <xs:attribute name="view_id" type="viewIdType"/>
        <xs:attribute name="class" type="classType"/>
        <xs:attribute name="shared_index" type="xs:string"/>
    </xs:complexType>

    <xs:group name="fieldset">
        <xs:choice>
            <xs:element name="fieldset" type="fieldsetType">
                <xs:unique name="uniqueField">
                    <xs:annotation>
                        <xs:documentation>
                            Field name must be unique in one fieldset.
                        </xs:documentation>
                    </xs:annotation>
                    <xs:selector xpath=".//fieldset/field"/>
                    <xs:field xpath="@name"/>
                </xs:unique>
            </xs:element>
        </xs:choice>
    </xs:group>

    <xs:complexType name="translatableType">
        <xs:simpleContent>
            <xs:extension base="xs:string">
                <xs:attribute name="translate" fixed="true" type="xs:boolean"/>
            </xs:extension>
        </xs:simpleContent>
    </xs:complexType>

    <xs:simpleType name="viewIdType">
        <xs:annotation>
            <xs:documentation>
                View ID can contain only [a-zA-Z0-9_].
            </xs:documentation>
        </xs:annotation>
        <xs:restriction base="xs:string">
            <xs:pattern value="[a-zA-Z0-9_]+"/>
        </xs:restriction>
    </xs:simpleType>

    <xs:simpleType name="classType">
        <xs:annotation>
            <xs:documentation>
                Class name can contain only [a-zA-Z|\\]+[a-zA-Z0-9\\]+.
            </xs:documentation>
        </xs:annotation>
        <xs:restriction base="xs:string">
            <xs:pattern value="[a-zA-Z|\\]+[a-zA-Z0-9\\]+"/>
        </xs:restriction>
    </xs:simpleType>

    <xs:simpleType name="fromType">
        <xs:annotation>
            <xs:documentation>
                From attribute can contain only [a-zA-Z0-9_].
            </xs:documentation>
        </xs:annotation>
        <xs:restriction base="xs:string">
            <xs:pattern value="[a-zA-Z0-9_]+"/>
        </xs:restriction>
    </xs:simpleType>

    <xs:simpleType name="toType">
        <xs:annotation>
            <xs:documentation>
                To attribute can contain only [a-zA-Z0-9_].
            </xs:documentation>
        </xs:annotation>
        <xs:restriction base="xs:string">
            <xs:pattern value="[a-zA-Z0-9_]+"/>
        </xs:restriction>
    </xs:simpleType>

    <xs:simpleType name="originType">
        <xs:annotation>
            <xs:documentation>
                To attribute can contain only [a-zA-Z0-9_].
            </xs:documentation>
        </xs:annotation>
        <xs:restriction base="xs:string">
            <xs:pattern value="[a-zA-Z0-9_]+"/>
        </xs:restriction>
    </xs:simpleType>

    <xs:simpleType name="nameType">
        <xs:annotation>
            <xs:documentation>
                Class name can contain only [a-zA-Z\].
            </xs:documentation>
        </xs:annotation>
        <xs:restriction base="xs:string">
            <xs:pattern value="[a-zA-Z0-9_]+"/>
        </xs:restriction>
    </xs:simpleType>

    <xs:complexType name="fieldTypeAbstract" abstract="true">
        <xs:annotation>
            <xs:documentation>
                Index field declaration.
            </xs:documentation>
        </xs:annotation>
        <xs:attribute name="name" type="nameType" use="required"/>
        <xs:attribute name="handler" type="classType"/>
        <xs:attribute name="origin" type="originType"/>
    </xs:complexType>

    <xs:complexType name="fieldsetType" mixed="true">
        <xs:annotation>
            <xs:documentation>
                Fieldset of field declaration.
            </xs:documentation>
        </xs:annotation>
        <xs:sequence>
            <xs:element type="referenceType" name="reference" minOccurs="0" maxOccurs="unbounded"/>
            <xs:element name="field" type="fieldType" minOccurs="0" maxOccurs="unbounded"/>
        </xs:sequence>
        <xs:attribute name="source" type="classType"/>
        <xs:attribute name="provider" type="classType"/>
        <xs:attribute name="name" type="nameType" use="required"/>
    </xs:complexType>

    <xs:complexType name="fieldType">
        <xs:complexContent>
            <xs:extension base="fieldTypeAbstract">
                <xs:choice>
                    <xs:element type="filterType" name="filter" minOccurs="0" maxOccurs="1"/>
                </xs:choice>
                <xs:attribute type="dataType" name="dataType"/>
            </xs:extension>
        </xs:complexContent>
    </xs:complexType>

    <xs:complexType name="filterType">
        <xs:annotation>
            <xs:documentation>
                Index field filter.
            </xs:documentation>
        </xs:annotation>
        <xs:attribute name="class" type="classType" use="required"/>
    </xs:complexType>

    <xs:complexType name="structureType">
        <xs:annotation>
            <xs:documentation>
                Structure type.
            </xs:documentation>
        </xs:annotation>
        <xs:attribute name="class" type="classType" use="required"/>
    </xs:complexType>

    <xs:complexType name="saveHandlerType">
        <xs:annotation>
            <xs:documentation>
                SaveHandler type.
            </xs:documentation>
        </xs:annotation>
        <xs:attribute name="class" type="classType" use="required"/>
    </xs:complexType>

    <xs:complexType name="referenceType">
        <xs:annotation>
            <xs:documentation>
                Index field reference.
            </xs:documentation>
        </xs:annotation>
        <xs:attribute name="fieldset" type="nameType" use="required"/>
        <xs:attribute name="from" type="fromType"/>
        <xs:attribute name="to" type="toType"/>
    </xs:complexType>

    <xs:simpleType name="dataType">
        <xs:restriction base="xs:string">
            <xs:enumeration value="int"/>
            <xs:enumeration value="float"/>
            <xs:enumeration value="varchar"/>
            <xs:enumeration value="text"/>
            <xs:enumeration value="mediumtext"/>
            <xs:enumeration value="timestamp"/>
            <xs:enumeration value="datetime"/>
            <xs:enumeration value="date"/>
        </xs:restriction>
    </xs:simpleType>

    <xs:complexType name="searchable">
        <xs:complexContent>
            <xs:extension base="fieldType"/>
        </xs:complexContent>
    </xs:complexType>

    <xs:complexType name="filterable">
        <xs:complexContent>
            <xs:extension base="fieldType"/>
        </xs:complexContent>
    </xs:complexType>

    <xs:element name="config" type="configType">
        <xs:unique name="uniqueIndexerId">
            <xs:annotation>
                <xs:documentation>
                    Indexer Id must be unique.
                </xs:documentation>
            </xs:annotation>
            <xs:selector xpath="indexer"/>
            <xs:field xpath="@id"/>
        </xs:unique>
        <xs:unique name="uniqueViewId">
            <xs:annotation>
                <xs:documentation>
                    Indexer Id must be unique.
                </xs:documentation>
            </xs:annotation>
            <xs:selector xpath="indexer"/>
            <xs:field xpath="@view_id"/>
        </xs:unique>
    </xs:element>
    <xs:complexType name="configType">
        <xs:sequence>
            <xs:element ref="indexer"  minOccurs="1" maxOccurs="unbounded"/>
        </xs:sequence>
    </xs:complexType>

    <xs:element name="indexer" type="indexerType">
        <xs:unique name="uniqueFieldset">
            <xs:annotation>
                <xs:documentation>
                    Fieldset name must be unique.
                </xs:documentation>
            </xs:annotation>
            <xs:selector xpath=".//fieldset"/>
            <xs:field xpath="@name"/>
        </xs:unique>
    </xs:element>

    <xs:group name="dependencies">
        <xs:choice>
            <xs:element minOccurs="0" maxOccurs="1" name="dependencies" type="indexerDependencies">
                <xs:unique name="uniqueIndexerDependency">
                    <xs:annotation>
                        <xs:documentation>
                            Related indexer id must be unique.
                        </xs:documentation>
                    </xs:annotation>
                    <xs:selector xpath="indexer"/>
                    <xs:field xpath="@id"/>
                </xs:unique>
            </xs:element>
        </xs:choice>
    </xs:group>

    <xs:complexType name="indexerDependencies">
        <xs:annotation>
            <xs:documentation>
                Root element of the indexer dependencies.
            </xs:documentation>
        </xs:annotation>
        <xs:sequence maxOccurs="unbounded">
            <xs:element minOccurs="0" maxOccurs="unbounded" name="indexer">
                <xs:complexType>
                    <xs:annotation>
                        <xs:documentation>
                            Indexer dependency that represents another indexer.
                        </xs:documentation>
                    </xs:annotation>
                    <xs:attribute name="id" type="xs:string" use="required"/>
                </xs:complexType>
            </xs:element>
        </xs:sequence>
    </xs:complexType>
</xs:schema>