displaying the unique tags in a XML RSS Feed using PHP

tags_display.php

<?php
$url = $_GET['feed_url'];
ini_set( "display_errors", 0);

if(@$test = file_get_contents($url))
{  
	if($xml = simplexml_load_string($test))
	{
		$search  = array('<', '>', 'red</font>&gt;');
		$replace = array('&lt;<font color=red>', '</font>&gt;','red>');
		$disp = str_replace($search, $replace, $test);
		
		//echo "<pre>".$disp."</pre>";
		
		
		$json=json_encode($xml);
		
		
		$test_a=json_decode($json, true);
		echo "<br><br>";
		
		echo "Please check the tags of whose values you need as a update<br><br>";
		processArray($test_a,"root");

		echo "<input type='hidden' name='url_valid_flag' id='url_valid_flag' value='1'>
			<br><input type='hidden' name='xml_string' id='xml_string' value='".$xml."'>"; //for form validation of check boxes of tags, 0 for invalid url, 1 for valid url
			
	}
		
	else if($test_a=json_decode($test, true))
	{
		//echo "Check the <a href='xml-display.php?url=$url' target='_blank'>xml</a> available for the $url <br><br>";
		echo "Please check the tags of whose values you need as a update<br><br>";
		
		processArray($test_a,"root");

		echo "<input type='hidden' name='url_valid_flag' id='url_valid_flag' value='1'>
				<br><input type='hidden' name='xml_string' id='xml_string' value='".$xml."'>"; //for form validation of check boxes of tags, 0 for invalid url, 1 for valid url
	}
	else
	{
		echo "<br><center><font color=red>Please enter a valid URL containing XML data</font><center>";
	
		echo "<input type='hidden' name='url_valid_flag' id='url_valid_flag' value='0'>"; //for form validation of check boxes of tags, 0 for invalid url, 1 for valid url
	
	
	}
}

else
{
	echo "<br><center><font color=red>Please enter a valid URL</font><center>";

	echo "<input type='hidden' name='url_valid_flag' id='url_valid_flag' value='0'>"; //for form validation of check boxes of tags, 0 for invalid url, 1 for valid url
}


function processArray($array,$parent_p) {
	 
		global $count;
	 
		$count++; //this variable is for calculating tab space
		$parent=$parent_p;
		if(is_array($array) === true) 
		{
			
			foreach($array as $key => $value) 
			{
				$parent_2=$parent_p;
				
				if(is_array($value)==true  && is_numeric($key)!=true)  // for getting the parent node name properly.
				{
					$parent=$key;
					
				}
				
				if(is_array($value) === true) 
				{
					
					
					if(is_numeric($key) != true)   // for displaying the parent node, just for reference.
					{
						for($i = 1 ; $i < $count ; $i++) echo "&nbsp;&nbsp;"; //change this to space ' ' if running from CLI
						echo "<font color='red'>".$key."</font><br/>";
					}
					
					$size=count($array);
					if(is_numeric($key)== true)    // for not displaying the duplicates.
					{
					
						for($j=0; $j<($size-1); $j++)
						{
							
							array_pop($array);
						}
					}
					
					@processArray($array[$key],$parent);
					
				}
				else 
				{
					for($i = 1 ; $i < $count ; $i++) echo "&nbsp;&nbsp;"; 

					echo "<input type='checkbox' name='tags[]' id='tags' value=".$key."_".$parent_2.">".$key."<br />";
				}
			}
		}
		//echo "<font color=blue>".$parent_2."</font><br>";
	 
		$count--;
	}

?>