#	Copyright 2008 Josh Erickson (josh dot sonshine at gmail dot com)
#
#	mergeXML :: Merge two XML Documents into one.
#
#		Everything from $from, will be copied to $to. Any duplicate 
#		attributes will be overwritten with data from $from. Nodes in 
#		$from will be appended to their mirror location in $to.
#
#	Arguments
#		$from	- The XML document that will be copied.
#		$to		- XML document that $from will be copied to.
#
#

function mergeXML {
	$from = $args[0][0];
	$to = $args[0][1];
	
	if(![bool]"$($from | gm)".contains("System.Xml.XmlDocument") -or ![bool]"$($to | gm)".contains("System.Xml.XmlDocument")) { return -1; }
	if(![bool]$from.get_HasChildNodes() -or ![bool]$to.get_HasChildNodes()) { return "-2:$($from.get_name()):$($to.get_name())"; }
	
	$fchild = $from.get_childnodes();
	$tchild = $to.get_childnodes();
	
	#foreach($fci in $fchild) {
	for([int]$i=0;$i -lt $fchild.count;$i++) {
		$fci = $fchild.item($i);
		
		if(($tci = $to."$($fci.get_name())") -eq $Null) {
			$e = $fci.cloneNode($True);
			if("$($fci.get_parentNode().get_name())" -eq "#document") {
				$to.ImportNode($fci,$True);
				$to.normalize();
			} else {
				$tci = $to.get_ownerDocument().importNode($fci,$True) # | set-Variable -name tci;				
				$to.AppendChild($tci);
				$to.normalize();
			}
		}
		
		foreach($fcai in $fci.get_attributes()) {
			$tci.setAttribute($fcai.get_name(),$fcai.get_value());
		}
		
		if($fci.get_HasChildNodes()) {
			mergeXML($fci,$tci);
		}
	}
}