nested grouping

Dear All,
I have a problem with grouping. I name it double grouping as I cant get a
better name gor it.
Here it goes. I have an XML which looks like

<?xml version="1.0"?>
<films>
 <slot id = "1">
  <date>day1</date>
  <film id = "horror">Horror-Movie1</film>
 </slot>
 <slot id = "2">
  <date>day1</date>
  <film id = "horror">Horror-Movie2</film>
 </slot>
 <slot id = "3">
  <date>day1</date>
  <film id = "adult">Adult-Movie1</film>
 </slot>
 <slot id = "4">
  <date>day1</date>
  <film id = "adult">Adult-Movie2</film>
 </slot>
 <slot id = "5">
  <date>day2</date>
  <film id = "horror">Horror-Movie3</film>
 </slot>
 <slot id = "6">
  <date>day2</date>
  <film id = "horror">Horror-Movie4</film>
 </slot>
 <slot id = "7">
  <date>day2</date>
  <film id = "adult">Adult-Movie3</film>
 </slot>
 <slot id = "8">
  <date>day2</date>
  <film id = "adult">Adult-Movie4</film>
 </slot>
</films>
and i want to group based on date and within that based on film ids..

In other words, I want the output (HTML) to look like:

Date ** day1
  Horror Movies
    Film Type : horror ** Film :Horror-Movie1
    Film Type : horror ** Film :Horror-Movie2
  Adult Movies
    Film Type : adult ** Film :Adult-Movie1
    Film Type : adult ** Film :Adult-Movie2
Date ** day2

Horror Movies
    Film Type : horror ** Film :Horror-Movie3
    Film Type : horror ** Film :Horror-Movie4
Adult Movies
    Film Type : adult ** Film :Adult-Movie3
    Film Type : adult ** Film :Adult-Movie4


I wrote an xsl that would go as far as grouping based on the dates..to
produce an output that looks like..

Date ** day1
Film Type : horror ** Film :Horror-Movie1
Film Type : horror ** Film :Horror-Movie2
Film Type : adult ** Film :Adult-Movie1
Film Type : adult ** Film :Adult-Movie2
Date ** day2
Film Type : horror ** Film :Horror-Movie1
Film Type : horror ** Film :Horror-Movie1
Film Type : adult ** Film :Adult-Movie1
Film Type : adult ** Film :Adult-Movie2

I cant get my heads around doing what I want. I tried many weird combination
using the keys but couldnt get what I wanted The xsl i wrote is as follows..

<?xml version="1.0"?>
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:key match="/films/slot" name="unigue-days" use="date/text()"/>
 <xsl:template match="/">
  <xsl:for-each select="/films/slot[generate-id(.) =
generate-id(key('unique-days',date/text())[1])]">
   <u><b> Date ** <xsl:value-of select="date"/></b></u>
   <br/>
   <xsl:for-each select="key('unique-days',date/text())">
     Film Type : <b> <xsl:value-of select="film/@id"/></b> **
    Film :<b><xsl:value-of select="film"/></b>

    <br/>
   </xsl:for-each>
   <hr/>
  </xsl:for-each>
 </xsl:template>
</xsl:stylesheet>.


It would be of great help if someone could suggest me some way of grouping
elements in the way I wanted.
Cheers.

 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list