Convert XBEL file

<?xml version="1.0" encoding="UTF-8"?>
<xbel version="1.0">
  <folder id="1773">
    <title>Search</title>
    <bookmark href="https://search.brave.com/" id="1775">
      <title>Brave</title>
    </bookmark>
    <bookmark href="https://www.ecosia.org/" id="1776">
      <title>Ecosia</title>
    </bookmark>
    <bookmark href="https://www.startpage.com/en/" id="1777">
      <title>Startpage</title>
    </bookmark>
    <bookmark href="https://www.google.co.uk/" id="1778">
      <title>Google</title>
    </bookmark>
  </folder>
  <folder id="1449">
    <title>Sport</title>
    <folder id="1658">
      <title>Golf</title>
      <folder id="1693">
        <title>Golf Clubs</title>
        <bookmark href="https://www.golfbidder.co.uk/guides-and-advice/the-clubhouse/best-beginner-iron-sets" id="1690">
          <title>10 Best Iron Sets for Beginners</title>
        </bookmark>
        <bookmark href="https://www.golfbidder.co.uk/taylormade-m2-2019-iron-set" id="1691">
          <title>TaylorMade M2 2019</title>
        </bookmark>
        <bookmark href="https://www.golfbidder.co.uk/mizuno-jpx-919-hot-metal-iron-set" id="1692">
          <title>Mizuno JPX 919</title>
        </bookmark>
        <bookmark href="https://www.golfclubs4cash.co.uk/collections/ping-drivers" id="1696">
          <title>Used PING Drivers That Will Revolutionise Your Game.</title>
        </bookmark>
      </folder>
    </folder>
  </folder>
</xbel>

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet exclude-result-prefixes="exsl" version="1.0" xmlns:exsl="http://exslt.org/common" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <xsl:strip-space elements="*"/>
    <xsl:preserve-space elements="value component operation-data password check-password"/>
    <xsl:output indent="yes" method="xml"/>

<xsl:template match="xbel">
    <xsl:apply-templates select="folder" />
</xsl:template>

<xsl:template match="folder">
    <xsl:param name="folderName"/>
    <xsl:variable name="varFolderName" select="./title/text()" />
    <xsl:variable name="varLevel">
        <xsl:choose>
            <xsl:when test="string-length($folderName) > 0">
                <xsl:value-of select="concat($folderName, '/', $varFolderName)" />
            </xsl:when>
            <xsl:otherwise>
                <xsl:value-of select="$varFolderName" />
            </xsl:otherwise>
        </xsl:choose>
    </xsl:variable>
    <xsl:for-each select="./bookmark">
        <xsl:variable name="varURL" select="./@href" />
        <xsl:variable name="varCurrent" select="." />
        <xsl:message>
            <xsl:value-of select="$varLevel" />
            <xsl:value-of select="'|'" />
            <xsl:value-of select="$varCurrent" />
            <xsl:value-of select="'|'" />
            <xsl:value-of select="$varURL" />
        </xsl:message>
    </xsl:for-each>
    <xsl:if test="folder">
        <xsl:apply-templates select="folder">
            <xsl:with-param name="folderName"><xsl:value-of select="$varLevel" /></xsl:with-param>
        </xsl:apply-templates>
    </xsl:if>
</xsl:template>

<xsl:template match="node()|@*">
    <xsl:apply-templates select="@*|node()"/>
</xsl:template>

</xsl:stylesheet>