I want to group by headers, but when the structure isn't logical the sectioning stops. For example <h2> followed by <h4>. See example. I would like to see the <h4> sectioned when there is no <h3> but I can't seem to get it work. Could someone help me with that? I work with xslt 2.0.
Input:
<?xml version="1.0" encoding="UTF-8"?>
<document id="21" state="Schrijven" documentTypeName="News">
<document track-changes="false" version="1">
<section>
<h1>Title h1</h1>
<p>Some text</p>
<p/>
<h2>Title h2</h2>
<p>Some text</p>
<p/>
<h3>Title h3</h3>
<p>Some text</p>
<p/>
<h2>Title h2</h2>
<p>Some text</p>
<p/>
<h4>Title h4</h4>
<p>Some text</p>
<p/>
</section>
</document>
</document>
Output
<html>
<head>
<meta charset="UTF-8"/>
</head>
<body data-sws-documentkey="id-00021">
<section class="level-newsitem">
<h1 class="nieuws">Title h1</h1>
<p>Some text</p>
<p/>
<section class="level">
<h2>Title h2</h2>
<p>Some text</p>
<p/>
<section class="level">
<h3>Title h3</h3>
<p>Some text</p>
<p/>
</section>
</section>
<section class="level">
<h2>Title h2</h2>
<p>Some text</p>
<p/>
<h4>Title h4</h4>
<p>Some text</p>
<p/>
</section>
</section>
</body>
</html>
Desired Output
<html>
<head>
<meta charset="UTF-8"/>
</head>
<body data-sws-documentkey="id-00021">
<section class="level-newsitem">
<h1 class="nieuws">Title h1</h1>
<p>Some text</p>
<p/>
<section class="level">
<h2>Title h2</h2>
<p>Some text</p>
<p/>
<section class="level">
<h3>Title h3</h3>
<p>Some text</p>
<p/>
</section>
</section>
<section class="level">
<h2>Title h2</h2>
<p>Some text</p>
<p/>
<section class="level">
<h4>Title h4</h4>
<p>Some text</p>
<p/>
</section>
</section>
</section>
</body>
</html>
Stylesheet
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:cwc="urn:cwc"
xmlns:p1="urn:p1"
exclude-result-prefixes="xs cwc p1"
version="2.0">
<xsl:output method="xml" indent="yes" encoding="UTF-8"/>
<xsl:strip-space elements="document meta section div row"/>
<xsl:variable name="DocumentKey">
<xsl:value-of select="concat('id-000', /document[1]/@id)"/>
</xsl:variable>
<xsl:variable name="DocSoort">
<xsl:value-of select="/document/@documentTypeName"/>
</xsl:variable>
<xsl:template match="document">
<html>
<head>
<meta charset="UTF-8"/>
<xsl:if test="./meta/description">
<meta name="description">
<xsl:attribute name="content">
<xsl:value-of select="./meta/description"/>
</xsl:attribute>
</meta>
</xsl:if>
<title><xsl:value-of select="./naam"/></title>
</head>
<body data-sws-documentkey="{$DocumentKey}">
<xsl:choose>
<xsl:when test="$DocSoort='Note'">
<xsl:apply-templates mode="Note"/>
</xsl:when>
<xsl:when test="$DocSoort='News'">
<xsl:apply-templates mode="News"/></xsl:when>
</xsl:choose>
</body>
</html>
</xsl:template>
<xsl:template match="h1" mode="#all">
<xsl:variable name="DocSoorttitel">
<xsl:choose>
<xsl:when test="$DocSoort='Note'">noteitem</xsl:when>
<xsl:when test="$DocSoort='News'">newsitem</xsl:when>
</xsl:choose>
</xsl:variable>
<xsl:variable name="count">
<xsl:value-of select="count(preceding::h1)"/>
</xsl:variable>
<xsl:choose>
<xsl:when test="$count = 0">
<xsl:copy>
<xsl:attribute name="class">
<xsl:value-of select="$DocSoorttitel"/>
</xsl:attribute>
<xsl:apply-templates select="@*[name()!='class']" mode="#current"/>
<xsl:apply-templates mode="#current"/>
</xsl:copy>
</xsl:when>
<xsl:otherwise>
<xsl:copy>
<xsl:apply-templates select="@*" mode="#current"/>
<xsl:apply-templates mode="#current"/>
</xsl:copy>
</xsl:otherwise>
</xsl:choose>
</xsl:template>
<xsl:template match="naam|meta|lastmodified" mode="#all"/>
<xsl:template match="*/document" mode="#all">
<xsl:choose>
<xsl:when test="not(./section)">
<section>
<xsl:attribute name="class">
<xsl:value-of select="lower-case(concat('sws-', $DocSoort))"/>
</xsl:attribute>
<xsl:call-template name="groupingheaders"/>
</section>
</xsl:when>
<xsl:otherwise>
<xsl:apply-templates mode="#current"/>
</xsl:otherwise>
</xsl:choose>
</xsl:template>
<xsl:template match="section" mode="#all">
<section>
<xsl:attribute name="class">
<xsl:value-of select="lower-case(concat('level-', $DocSoort))"/>
</xsl:attribute>
<xsl:call-template name="groupingheaders"/>
</section>
</xsl:template>
<xsl:template name="groupingheaders">
<xsl:choose>
<xsl:when test="$DocSoort='Note'">
<xsl:for-each-group select="*" group-starting-with="div[@class = 'letop'][parent::document or parent::section]|h2[parent::document or parent::section][count(text()[normalize-space()]) > 0]">
<xsl:choose>
<xsl:when test="current-group()[1]/self::div[@class = 'letop'][parent::document or parent::section]|current-group()[1]/self::h2[parent::document or parent::section][count(text()[normalize-space()]) > 0]">
<section class="level">
<xsl:call-template name="group2"/>
</section>
</xsl:when>
<xsl:otherwise>
<xsl:apply-templates select="current-group()" mode="#current"/>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each-group>
</xsl:when>
<xsl:when test="$DocSoort='News'">
<xsl:for-each-group select="*" group-starting-with="h2[parent::document or parent::section][count(text()[normalize-space()]) > 0]">
<xsl:choose>
<xsl:when test="current-group()[1]/self::h2[parent::document or parent::section][count(text()[normalize-space()]) > 0]">
<section class="level">
<xsl:call-template name="group2"/>
</section>
</xsl:when>
<xsl:otherwise>
<xsl:apply-templates select="current-group()" mode="#current"/>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each-group>
</xsl:when>
</xsl:choose>
</xsl:template>
<xsl:template name="group2">
<xsl:for-each-group select="current-group()" group-starting-with="h3[parent::document or parent::section][count(text()[normalize-space()]) > 0]">
<xsl:choose>
<xsl:when test="current-group()[1]/self::h3[parent::document or parent::section][count(text()[normalize-space()]) > 0]">
<section class="level">
<xsl:call-template name="group3"/>
</section>
</xsl:when>
<xsl:otherwise>
<xsl:apply-templates select="current-group()" mode="#current"/>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each-group>
</xsl:template>
<xsl:template name="group3">
<xsl:for-each-group select="current-group()" group-starting-with="h4[parent::document or parent::section][count(text()[normalize-space()]) > 0]">
<xsl:choose>
<xsl:when test="current-group()[1]/self::h4[parent::document or parent::section][count(text()[normalize-space()]) > 0]">
<section class="level">
<xsl:call-template name="group4"/>
</section>
</xsl:when>
<xsl:otherwise>
<xsl:apply-templates select="current-group()" mode="#current"/>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each-group>
</xsl:template>
<xsl:template name="group4">
<xsl:for-each-group select="current-group()" group-starting-with="h5[parent::document or parent::section][count(text()[normalize-space()]) > 0]">
<xsl:choose>
<xsl:when test="current-group()[1]/self::h5[parent::document or parent::section][count(text()[normalize-space()]) > 0]">
<section class="level">
<xsl:call-template name="group5"/>
</section>
</xsl:when>
<xsl:otherwise>
<xsl:apply-templates select="current-group()" mode="#current"/>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each-group>
</xsl:template>
<xsl:template name="group5">
<xsl:for-each-group select="current-group()" group-starting-with="h6[parent::document or parent::section][count(text()[normalize-space()]) > 0]">
<xsl:choose>
<xsl:when test="current-group()[1]/self::h6[parent::document or parent::section][count(text()[normalize-space()]) > 0]">
<section class="level">
<xsl:apply-templates select="current-group()" mode="#current"/>
</section>
</xsl:when>
<xsl:otherwise>
<xsl:apply-templates select="current-group()" mode="#current"/>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each-group>
</xsl:template>
<xsl:template match="node()" mode="#all">
<xsl:copy>
<xsl:apply-templates select="node()" mode="#current"/>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
A regular grouping can be done with a recursive function:
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:mf="http://example.com/mf"
exclude-result-prefixes="xs mf"
version="2.0">
<xsl:output method="html" indent="yes"/>
<xsl:param name="prefix" as="xs:string" select="'h'"/>
<xsl:param name="max-level" as="xs:integer" select="6"/>
<xsl:function name="mf:group" as="node()*">
<xsl:param name="nodes" as="node()*"/>
<xsl:param name="level" as="xs:integer"/>
<xsl:for-each-group select="$nodes" group-starting-with="*[local-name() eq concat($prefix, $level)]">
<xsl:choose>
<xsl:when test="self::*[local-name() eq concat($prefix, $level)]">
<section class="level">
<xsl:apply-templates select="."/>
<xsl:sequence select="mf:group(current-group() except ., $level + 1)"/>
</section>
</xsl:when>
<xsl:when test="$level lt $max-level">
<xsl:sequence select="mf:group(current-group(), $level + 1)"/>
</xsl:when>
<xsl:otherwise>
<xsl:apply-templates select="current-group()"/>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each-group>
</xsl:function>
<xsl:template match="@* | node()">
<xsl:copy>
<xsl:apply-templates select="@* , node()"/>
</xsl:copy>
</xsl:template>
<xsl:template match="*[h1 | h2 | h3 | h4 | h5 | h6]">
<xsl:copy>
<xsl:sequence select="mf:group(*, 1)"/>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
That transforms
<document id="21" state="Schrijven" documentTypeName="News">
<document track-changes="false" version="1">
<section>
<h1>Title h1</h1>
<p>Some text</p>
<p/>
<h2>Title h2</h2>
<p>Some text</p>
<p/>
<h3>Title h3</h3>
<p>Some text</p>
<p/>
<h2>Title h2</h2>
<p>Some text</p>
<p/>
<h4>Title h4</h4>
<p>Some text</p>
<p/>
</section>
</document>
</document>
into
<document id="21" state="Schrijven" documentTypeName="News">
<document track-changes="false" version="1">
<section>
<section class="level">
<h1>Title h1</h1>
<p>Some text</p>
<p></p>
<section class="level">
<h2>Title h2</h2>
<p>Some text</p>
<p></p>
<section class="level">
<h3>Title h3</h3>
<p>Some text</p>
<p></p>
</section>
</section>
<section class="level">
<h2>Title h2</h2>
<p>Some text</p>
<p></p>
<section class="level">
<h4>Title h4</h4>
<p>Some text</p>
<p></p>
</section>
</section>
</section>
</section>
</document>
</document>
You need to add your templates for the other elements and maybe, if the first level needs special treatment, extend the function with some conditional checks or write a template or function for the first level.