I have the XSLT below which always create three levels of menu, always starting at a specific level.  I want to change it so that:

If the current page (no matter how deep) has children, show PARENT / SELF / CHILDREN as the three levels.

If the current page (no matter how deep) has no children, show GRANDPARENT / PARENT / SELF as the three levels.

In both cases, never go any higher than the highest page using template=1165.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE xsl:stylesheet [ <!ENTITY nbsp "&#x00A0;"> ]>
<xsl:stylesheet 
  version="1.0" 
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
  xmlns:msxml="urn:schemas-microsoft-com:xslt" 
  xmlns:umbraco.library="urn:umbraco.library" xmlns:Exslt.ExsltCommon="urn:Exslt.ExsltCommon" xmlns:Exslt.ExsltDatesAndTimes="urn:Exslt.ExsltDatesAndTimes" xmlns:Exslt.ExsltMath="urn:Exslt.ExsltMath" xmlns:Exslt.ExsltRegularExpressions="urn:Exslt.ExsltRegularExpressions" xmlns:Exslt.ExsltStrings="urn:Exslt.ExsltStrings" xmlns:Exslt.ExsltSets="urn:Exslt.ExsltSets" 
  exclude-result-prefixes="msxml umbraco.library Exslt.ExsltCommon Exslt.ExsltDatesAndTimes Exslt.ExsltMath Exslt.ExsltRegularExpressions Exslt.ExsltStrings Exslt.ExsltSets ">

<xsl:output method="xml" omit-xml-declaration="yes" />

<xsl:param name="currentPage"/>

<xsl:template match="/">

  <xsl:if test="count($currentPage/ancestor-or-self::* [@template=1165 and string(umbracoNaviHide) != '1']) &gt; 0">
    <div class="block">
      <xsl:for-each select="$currentPage/ancestor-or-self::* [@template=1165 and string(umbracoNaviHide) != '1']">
        <h3>
          <a href="{umbraco.library:NiceUrl(@id)}">
            <xsl:value-of select="@nodeName"/>
          </a>
        </h3>
      </xsl:for-each>

      <ul class="products">
        <xsl:for-each select="$currentPage/ancestor-or-self::* [@template=1165 and string(umbracoNaviHide) != '1']/* [@isDoc and string(umbracoNaviHide) != '1']">
          <xsl:variable name="subItems" select="umbraco.library:GetXmlNodeById(@id)/child::* [@isDoc and string(umbracoNaviHide) != '1']"/>
          <li>
            <xsl:if test="count($subItems)">
              <xsl:attribute name="class">open</xsl:attribute>
            </xsl:if>
            <a href="{umbraco.library:NiceUrl(@id)}">
              <xsl:value-of select="@nodeName"/>
            </a>
            <xsl:if test="count($subItems)">
              <ul>
                <xsl:for-each select="$subItems">
                  <xsl:variable name="subSubItems" select="umbraco.library:GetXmlNodeById(@id)/child::* [@isDoc and string(umbracoNaviHide) != '1']"/>
                  <li>
                    <a href="{umbraco.library:NiceUrl(@id)}">
                      <xsl:value-of  select="@nodeName"/>
                    </a>
                    <xsl:if test="count($subSubItems)">
                      <ul>
                        <xsl:for-each select="$subSubItems">
                          <li>
                            <a href="{umbraco.library:NiceUrl(@id)}">
                              <xsl:value-of  select="@nodeName"/>
                            </a>
                          </li>
                        </xsl:for-each>
                      </ul>
                    </xsl:if>
                  </li>
                </xsl:for-each>
              </ul>
            </xsl:if>
          </li>
        </xsl:for-each>
      </ul>
    </div>
  </xsl:if>

</xsl:template>

</xsl:stylesheet>