xslt following group - xslt

Question

Old Source XML:
<Employees>
<Person>
<FirstName>Joy</FirstName>
<IsManager>N</IsManager>
</Person>
<Person>
<FirstName>Joyce</FirstName>
<IsManager>N</IsManager>
</Person>
<Person>
<FirstName>Joe</FirstName>
<IsManager>Y</IsManager>
</Person>...
</Employees>
New Source XML:
<Employees>
<Person>
<FirstName>Joy</FirstName>
<DetailsArray>
<Details1>
<IsManager>N</IsManager>
<IsSuperviser>N</IsSuperviser>
</Details1>
<Details2>
<IsManager>N</IsManager>
<IsSuperviser>N</IsSuperviser>
</Details2>
</DetailsArray>
</Person>
<Person>
<FirstName>Joyce</FirstName>
<DetailsArray>
<Details1>
<IsManager>N</IsManager>
<IsSuperviser>N</IsSuperviser>
</Details1>
<Details2>
<IsManager>N</IsManager>
<IsSuperviser>N</IsSuperviser>
</Details2>
</DetailsArray>
</Person>
<Person>
<FirstName>Joe</FirstName>
<DetailsArray>
<Details1>
<IsManager>N</IsManager>
<IsSuperviser>N</IsSuperviser>
</Details1>
<Details2>
<IsManager>Y</IsManager>
<IsSuperviser>N</IsSuperviser>
</Details2>
</DetailsArray>
</Person>...
</Employees>
output should be:
<Names>
<Name num='1'>Joe</Name>
<Name num='2'>Joy</Name>
<Name num='3'>Joyce</Name>
....
</Names>
This source XML has some adjustments when compared to previous XML. Here the new condition is "The person may be linked to 2projects or 2tasks", so that i need the output to start from the person with IsManager='Y' even if IsManager is 'y' in Details2 tag of DetailsArray. The output should not have duplications of Names. For suppose if we sort The names will be duplicated..
Thanks for the Previous answers..

Answer 1

EDIT. As lwburk points out, the original solution of this answer just sorts the nodes by IsManager.
Here is a solution that finds the first manager, prints it out, then cycles through the remaining people (cycling back to the beginning, if needed).
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="Employees">
<xsl:variable name="position" select="count(Person) - count(Person/IsManager[. = 'Y'][1]/../following-sibling::*)" />
<xsl:call-template name="person">
<xsl:with-param name="name" select="Person/IsManager[. = 'Y'][1]/../FirstName" />
<xsl:with-param name="position" select="'1'" />
</xsl:call-template>
<xsl:for-each select="Person[position() > $position]">
<xsl:call-template name="person" />
</xsl:for-each>
<xsl:for-each select="Person[position() < $position]">
<xsl:call-template name="person" />
</xsl:for-each>
</xsl:template>
<xsl:template name="person">
<xsl:param name="name" select="FirstName" />
<xsl:param name="position" select="position() + 1" />
<Name>
<xsl:attribute name="num"><xsl:value-of select="$position" /></xsl:attribute>
<xsl:value-of select="$name" />
</Name>
</xsl:template>
</xsl:stylesheet>
Old answer.
I'm not sure about your question, but I think you want to get all the names starting from the person with IsManager = Y. You can use <xsl:sort> by the IsManager value. Don't forget to specify "descending" in the attribute "order" (otherwise, the person with IsManager = Y will be the last one).
I wrote an example that works with your input data:
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="Employees">
<xsl:for-each select="Person">
<xsl:sort select="IsManager" order="descending" />
<Name>
<xsl:attribute name="num">
<xsl:value-of select="position()" />
</xsl:attribute>
<xsl:value-of select="FirstName" />
</Name>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>

Answer 2

This short and simple transformation (no modes, no variables, and only three templates):
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output omit-xml-declaration="yes" indent="yes"/>
<xsl:template match="/">
<Names>
<xsl:apply-templates select="*/Person[IsManager='Y'][1]"/>
</Names>
</xsl:template>
<xsl:template match="Person[IsManager='Y']">
<xsl:apply-templates select=
"FirstName |../Person[not(generate-id()=generate-id(current()))]
/FirstName
">
<xsl:sort select=
"generate-id(..) = generate-id(/*/*[IsManager = 'Y'][1])"
order="descending"/>
<xsl:sort select=
"boolean(../preceding-sibling::Person[IsManager='Y'])"
order="descending"/>
</xsl:apply-templates>
</xsl:template>
<xsl:template match="FirstName">
<Name num="{position()}"><xsl:value-of select="."/></Name>
</xsl:template>
</xsl:stylesheet>
when applied on the following XML (the same one as provided by #lwburk):
<Employees>
<Person>
<FirstName>Joy</FirstName>
<IsManager>N</IsManager>
</Person>
<Person>
<FirstName>Joyce</FirstName>
<IsManager>N</IsManager>
</Person>
<Person>
<FirstName>Joe</FirstName>
<IsManager>Y</IsManager>
</Person>
<Person>
<FirstName>Professor X</FirstName>
<IsManager>N</IsManager>
</Person>
<Person>
<FirstName>Songey</FirstName>
<IsManager>Y</IsManager>
</Person>
</Employees>
produces the wanted, correct result:
<Names>
<Name num="1">Joe</Name>
<Name num="2">Professor X</Name>
<Name num="3">Songey</Name>
<Name num="4">Joy</Name>
<Name num="5">Joyce</Name>
</Names>
Explanation:
This is a typical case of sorting using multiple keys.
The highest priority sorting criteria is whether the Person parent is the first manager.
The second priority sorting criteria is whether the parent Person is following a manager.
We use the fact that when sorting booleans false() comes before true(), therefore we are processing the sorted nodelist in descending order.

Answer 3

It sounds like you're trying to start at the the first manager and then processes all Person elements in order, cycling back around to the beginning to get all elements before the partition element.
The following stylesheet achieves the desired result:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="/">
<xsl:apply-templates select="Employees/Person"/>
</xsl:template>
<xsl:template match="Person[IsManager='Y'][1]">
<Name num="1">
<xsl:apply-templates select="FirstName"/>
</Name>
<!-- partition -->
<xsl:apply-templates select="following-sibling::Person" mode="after"/>
<xsl:apply-templates select="../Person" mode="before">
<xsl:with-param name="pos" select="last() - position() + 1"/>
</xsl:apply-templates>
</xsl:template>
<xsl:template match="Person" mode="after">
<Name num="{position() + 1}">
<xsl:apply-templates select="FirstName"/>
</Name>
</xsl:template>
<xsl:template match="Person[not(IsManager='Y') and
not(preceding-sibling::Person[IsManager='Y'])]" mode="before">
<xsl:param name="pos" select="0"/>
<Name num="{position() + $pos}">
<xsl:apply-templates select="FirstName"/>
</Name>
</xsl:template>
<xsl:template match="Person"/>
<xsl:template match="Person" mode="before"/>
</xsl:stylesheet>
Note: 1) This solution requires there be at least one manager present in the source; 2) This might not be a very efficient solution because it requires multiple passes and uses preceding-sibling to test group membership (for elements before the partition element).
Example input:
<Employees>
<Person>
<FirstName>Joy</FirstName>
<IsManager>N</IsManager>
</Person>
<Person>
<FirstName>Joyce</FirstName>
<IsManager>N</IsManager>
</Person>
<Person>
<FirstName>Joe</FirstName>
<IsManager>Y</IsManager>
</Person>
<Person>
<FirstName>Professor X</FirstName>
<IsManager>N</IsManager>
</Person>
<Person>
<FirstName>Songey</FirstName>
<IsManager>Y</IsManager>
</Person>
</Employees>
Output:
<Name num="1">Joe</Name>
<Name num="2">Professor X</Name>
<Name num="3">Songey</Name>
<Name num="4">Joy</Name>
<Name num="5">Joyce</Name>