Otherwise XSLT1.0 - correct output - xslt-1.0

Question

I´ve a problem at my xslt.
Here it is:
<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:msxsl="urn:schemas-microsoft-com:xslt" exclude-result-prefixes="msxsl">
<xsl:output method="xml" indent="yes"/>
<xsl:template match="#* | node()">
<xsl:copy>
<xsl:apply-templates select="#* | node()"/>
</xsl:copy>
</xsl:template>
<xsl:template match="GRP">
<xsl:copy>
<!--copy the data from ADD - ST to the GRP so it can be used in the mapping to set the delivery address from end customer-->
<xsl:for-each select ="./ADD">
<xsl:if test="./QUALIFIER='ST'">
<xsl:copy-of select="PARTY_NAME_1"/>
<xsl:copy-of select="STREET_1"/>
<xsl:copy-of select="CITY"/>
<xsl:copy-of select="POSTAL_CODE"/>
<xsl:copy-of select="COUNTRY_CODE"/>
</xsl:if>
<xsl:choose>
<xsl:when test="./QUALIFIER='CN'">
<CONTACT_NUMBER>
<xsl:value-of select="CONTACT/NUMBER"/>
</CONTACT_NUMBER>
</xsl:when>
<xsl:otherwise>
<xsl:if test="./QUALIFIER='ST'">
<CONTACT_NUMBER>
<xsl:value-of select="CONTACT/NUMBER"/>
</CONTACT_NUMBER>
</xsl:if>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each>
<!--copy all other nodes-->
<xsl:apply-templates select="#* | node()"/>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
Can you tell me, whats my mistake at my xml?
At my code i get Contact_Number 2 times.
I just like one of them... If Contact at CN - use this, otherwise use from ST.
-> If contact at CN and ST use CN.
Edit: xml:
<SEEDELFOR>
<GRP>
<ADD>
<QUALIFIER>CN</QUALIFIER>
<IDENTIFIER></IDENTIFIER>
<AGENCY_CODE></AGENCY_CODE>
<PARTY_NAME_1></PARTY_NAME_1>
<STREET_1></STREET_1>
<CITY></CITY>
<POSTAL_CODE></POSTAL_CODE>
<COUNTRY_CODE></COUNTRY_CODE>
<CONTACT>
<QUALIFIER></QUALIFIER>
<NUMBER>1111111</NUMBER>
</CONTACT>
</ADD>
<ADD>
<QUALIFIER>ST</QUALIFIER>
<IDENTIFIER></IDENTIFIER>
<AGENCY_CODE></AGENCY_CODE>
<PARTY_NAME_1></PARTY_NAME_1>
<STREET_1></STREET_1>
<CITY></CITY>
<POSTAL_CODE></POSTAL_CODE>
<CONTACT>
<QUALIFIER></QUALIFIER>
<NUMBER>2222222</NUMBER>
</CONTACT>
</ADD>
</GRP>
</SEEDELFOR>
How can i correct my xslt?
I hope you can help me.
Best regards
Julian

Answer 1

One of the way you can achieve this is, rewriting the template GRP as following:
<xsl:template match="GRP">
<xsl:copy>
<!--copy the data from ADD - ST to the GRP so it can be used in the mapping
to set the delivery address from end customer -->
<xsl:variable name="contact_ST">
<xsl:for-each select="./ADD">
<xsl:if test="./QUALIFIER='ST'">
<CONTACT_NUMBER>
<xsl:value-of select="CONTACT/NUMBER" />
</CONTACT_NUMBER>
</xsl:if>
</xsl:for-each>
</xsl:variable>
<xsl:variable name="contact_CN">
<xsl:for-each select="./ADD">
<xsl:if test="./QUALIFIER='CN'">
<CONTACT_NUMBER>
<xsl:value-of select="CONTACT/NUMBER" />
</CONTACT_NUMBER>
</xsl:if>
</xsl:for-each>
</xsl:variable>
<xsl:for-each select="./ADD">
<xsl:if test="./QUALIFIER='ST'">
<xsl:copy-of select="PARTY_NAME_1" />
<xsl:copy-of select="STREET_1" />
<xsl:copy-of select="CITY" />
<xsl:copy-of select="POSTAL_CODE" />
<xsl:copy-of select="COUNTRY_CODE" />
</xsl:if>
</xsl:for-each>
<xsl:choose>
<xsl:when test="$contact_CN != ''">
<xsl:copy-of select="$contact_CN" />
</xsl:when>
<xsl:otherwise>
<xsl:copy-of select="$contact_ST" />
</xsl:otherwise>
</xsl:choose>
<!--copy all other nodes -->
<xsl:apply-templates select="#* | node()" />
</xsl:copy>
</xsl:template>

Answer 2

Consider the following simplified example:
<xsl:template match="GRP">
<xsl:copy>
<!-- other code, if necessary-->
<xsl:variable name="cn" select="ADD[QUALIFIER='CN']" />
<xsl:variable name="st" select="ADD[QUALIFIER='ST']" />
<CONTACT_NUMBER>
<xsl:choose>
<xsl:when test="$cn">
<xsl:value-of select="$cn/CONTACT/NUMBER"/>
</xsl:when>
<xsl:otherwise>
<xsl:value-of select="$st/CONTACT/NUMBER"/>
</xsl:otherwise>
</xsl:choose>
</CONTACT_NUMBER>
<!-- more code, if necessary-->
</xsl:copy>
</xsl:template>