<?php

// Config option
$feed->sort_enclosures($order = array('flash', 'quicktime', 'wmedia'))
{
	/*
	* If an item contains multiple formats (i.e. Google Video), allow the user to prefer one handler over 
	  another (prefer Flash Video over QuickTime).

	* If multiple file types have the same handler, sort those file types in feed order.  Prefer the 
	  <media:content isDefault=""> value over other values.

	* For example: if an item contains .mov, .mp4, .flv, .avi, and .wmv, the default sorting (flash, quicktime, 
	  windows media, no handler), would reset the enclosure order to .flv, .mov, .mp4, .wmv, and .avi

	* Preferential sorting can be disabled by passing false as the parameter.

	* Should preferential sorting be on by default?  It would certainly be handy, but people may be used to 
	  the default sorting order.
	*/

	return true
}

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

if ($enclosure = $item->get_enclosure($key)) {

	/*
	* Because Media RSS has <media:group>s, one "enclosure" can have several versions of the same content (if we 
	  define an enclosure as a piece of content rather than just a file)

	* If there are zero <media:group>s, we can simply handle these are get_enclosure(0), get_enclosure(1), etc.  
	  Each enlosure would be treated as separate content.

	* If there is one <media:group>s, we can simply handle these are get_enclosure(0)->get_link(0), 
	  get_enclosure(0)->get_link(1), etc.  <enclosure> would be handled as part of this <media:group>

	* If there are two or more <media:group>s, we can simply handle these are get_enclosure(0)->get_link(0), 
	  get_enclosure(0)->get_link(1), etc.  First <enclosure> would be handled as part of the first <media:group>, 
	  the second would group with the second, etc. (It would really help to have a test feed for this to see if 
	  the solution makes sense.)

	Problems:
		* <media:thumbnail> is on a per-content basis.  Perhaps in the case of zero or one <media:group>s, we can 
		  simply apply this same thumbnail to all files.

		* What do we do if there are multiple <media:group>s?  Logically, we would support them the same way we do 
		  multiple enclosures, but then we have multiple[multiple] enclosures/groups.

	Possible Solution:
		* We can have enclosures with (possibly) multiple links.  We can handle this as $enclosure->get_link($key=0), 
		  with only one $enclosure->get_thumbnail(), and multiple categories as $enclosure->get_category($key=0) 
		  (like we do with items).

		* It is around this solution that I'm writing the following pseudocode.
		
		* Another possible solution would be to have other functions that are specific to MediaRSS/iTunes (i.e. 
		  $item->media_group(0)->get_link(0)) that would allow power users to have the kind of control they want.  
		  The standard enclosure() object (which would essentially be the easier-to-use version) would simply use 
		  the first file available (after obeying $feed->sort_enclosures(), <media:content isDefault>, etc.)
	*/

	$enclosure->get_extension($key = 0) {
		/*
		* Return the file extension of $this->get_link() with any query strings stripped off
		*/
	}

	$enclosure->get_length($key = 0) {
		/*
		* Return the length in bytes
		*/

		if (enclosure_tag) {
			return value of <enclosure length="">
		}
		else if (media_tag) {
			return value of <media:content fileSize="">
		}
	}

	$enclosure->get_link($key = 0) {
		/*
		* Return the URL(s) of the enclosure
		*/

		if (enclosure_tag) {
			return value of <enclosure url="">
		}
		else if (media_tag) {
			return value of <media:content url="">
		}
	}

	$enclosure->get_size($key = 0) {
		/*
		* Return value of $this->get_length(), converted to mebibytes (which are commonly mistaken to be megabytes).  
		  This is the most common/useful value for most audio/video files (few are usefully measured in KB, and fewer 
		  in GB).
		*/
		
		return ($this->get_length()/1024)/1024
	}

	$enclosure->get_type($key = 0) {
		/*
		* Return the mime type of the content
		*/

		if (enclosure_tag) {
			return value of <enclosure type="">
		}
		else if (media_tag) {
			return value of <media:content type="">
		}
	}

	$enclosure->get_handler($key = 0) {
		/*
		* Return the correct handler for the file

		* Useful for those who are writing their own embed code and don't want to do the mime-type/file-type processing 
		  that we already handle in embed().  As a matter of fact, that code should probably be pulled out into this 
		  function, and embed() would simply call it when necessary.
		*/

		return the correct handler for the content type (flash || flashmediaplayer || odeo || quicktime || windowsmedia)
	}

	$enclosure->get_duration($key = 0) {
		/*
		* Returns the amount of time (in seconds) the audio/video content takes to consume
		*/

		if (media_tag) {
			return <media:content duration="">
		}
		else if (itunes_tag) {
			return <itunes:duration>
		}
	}

	$enclosure->get_rating($key = 0) {
		/*
		* Returns the rating of the content
		
		* Media RSS can specify the kind of rating.  iTunes only cares whether content is explicit, non-explicit, or clean.

		* <media:adult> has been deprecated
		*/

		if (media_tag) {
			return array(
				'scheme' => 'icra',
				'value' => 'r (cz 1 lz 1 nz 1 oz 1 vz 1)'
			);
		}
		else if (itunes_tag) {
			return array(
				'scheme' => 'explicit',
				'value' => 'no'
			);
		}
	}
	
	/*
	THERE ARE OTHER MEDIA RSS AND ITUNES ELEMENTS AVAILABLE.  MAP THEM TOGETHER AS IT MAKES SENSE.
	*/

	$enclosure->get_extra_data($key = 0) {
		/*
		* Return additional data that may be available for a file
		
		* Probably most valuable for Media RSS
		*/

		return array(
			'bitrate' => '128', 
			'expression' => 'full',
			'framerate' => '25',
			'samplingrate' => '44.1'
			// etc.
		);
	}
}

?>