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<?php

add_filter( 'wp_footer' , 'add_wpdonations_scripts' );

/**
 * add_wpdonations_scripts
 *
 * @access      public
 * @since       1.0 
 * @return      void
*/
function add_wpdonations_scripts() {
	
	?>
	<script>
	function getUrlVars()
	{
	    var vars = [], hash;
	    var hashes = window.location.href.slice(window.location.href.indexOf('?') + 1).split('&');
	    for(var i = 0; i < hashes.length; i++)
	    {
	        hash = hashes[i].split('=');
	        vars.push(hash[0]);
	        vars[hash[0]] = hash[1];
	    }
	    return vars;
	}
	
	var campaign = getUrlVars()["campaign"];

	jQuery(document).ready(function(){
		if ( campaign ) {
			jQuery("#donation_campaign option").each(function()
			{
			    if( jQuery(this).val() != campaign && jQuery(this).val() != '' ) {
					jQuery( '#donation_campaign').replaceWith('<input type="text" name="donation_campaign" id="donation_campaign_input" value="' + campaign +'" disabled="disabled" readonly="readonly">');
					jQuery( '#donation_campaign_input + .description').remove();
			    }
			});
		}
	});
	</script>
	<?php
	
}