woocommerce/classes/shipping/shipping-free_shipping.php

<?php
/**
 * Free Shipping Method
 * 
 * A simple shipping method for free shipping
 *
 * @class 		free_shipping
 * @package		WooCommerce
 * @category	Shipping
 * @author		WooThemes
 */ 
class free_shipping extends woocommerce_shipping_method {
	
	function __construct() { 
        $this->id 			= 'free_shipping';
        $this->method_title = __('Free shipping', 'woothemes');
        $this->enabled		= get_option('woocommerce_free_shipping_enabled');
		$this->title 		= get_option('woocommerce_free_shipping_title');
		$this->min_amount 	= get_option('woocommerce_free_shipping_minimum_amount');
		$this->availability = get_option('woocommerce_free_shipping_availability');
		$this->countries 	= get_option('woocommerce_free_shipping_countries');
		
		add_action('woocommerce_update_options', array(&$this, 'process_admin_options'));
		add_option('woocommerce_free_shipping_availability', 'all');
		add_option('woocommerce_free_shipping_title', 'Free Shipping');
    } 
    
    function calculate_shipping() {
		$this->shipping_total 	= 0;
		$this->shipping_tax 	= 0;
		$this->shipping_label 	= $this->title;	    	
    }
    
    function admin_options() {
    	global $woocommerce;
    	?>
    	<h3><?php _e('Free Shipping', 'woothemes'); ?></h3>
    	<table class="form-table">
	    	<tr valign="top">
		        <th scope="row" class="titledesc"><?php _e('Enable/disable', 'woothemes') ?></th>
		        <td class="forminp">
		        	<fieldset><legend class="screen-reader-text"><span><?php _e('Enable/disable', 'woothemes') ?></span></legend>
						<label for="woocommerce_free_shipping_enabled>">
						<input name="woocommerce_free_shipping_enabled" id="woocommerce_free_shipping_enabled" type="checkbox" value="1" <?php checked(get_option('woocommerce_free_shipping_enabled'), 'yes'); ?> /> <?php _e('Enable Free Shipping', 'woothemes') ?></label><br>
					</fieldset>
		        </td>
		    </tr>
		    <tr valign="top">
		        <th scope="row" class="titledesc"><?php _e('Method Title', 'woothemes') ?></th>
		        <td class="forminp">
			        <input type="text" name="woocommerce_free_shipping_title" id="woocommerce_free_shipping_title" style="min-width:50px;" value="<?php if ($value = get_option('woocommerce_free_shipping_title')) echo $value; else echo 'Free Shipping'; ?>" /> <span class="description"><?php _e('This controls the title which the user sees during checkout.', 'woothemes') ?></span>
		        </td>
		    </tr>
		    <tr valign="top">
		        <th scope="row" class="titledesc"><?php _e('Minimum Order Amount', 'woothemes') ?></th>
		        <td class="forminp">
			        <input type="text" name="woocommerce_free_shipping_minimum_amount" id="woocommerce_free_shipping_minimum_amount" style="min-width:50px;" value="<?php if ($value = get_option('woocommerce_free_shipping_minimum_amount')) echo $value; ?>" /> <span class="description"><?php _e('Users will need to spend this amount to get free shipping. Leave blank to disable.', 'woothemes') ?></span>
		        </td>
		    </tr>
		    <tr valign="top">
		        <th scope="row" class="titledesc"><?php _e('Method availability', 'woothemes') ?></th>
		        <td class="forminp">
			        <select name="woocommerce_free_shipping_availability" id="woocommerce_free_shipping_availability" style="min-width:100px;">
			            <option value="all" <?php if (get_option('woocommerce_free_shipping_availability') == 'all') echo 'selected="selected"'; ?>><?php _e('All allowed countries', 'woothemes'); ?></option>
			            <option value="specific" <?php if (get_option('woocommerce_free_shipping_availability') == 'specific') echo 'selected="selected"'; ?>><?php _e('Specific Countries', 'woothemes'); ?></option>
			        </select>
		        </td>
		    </tr>
		    <?php
	    	$countries = $woocommerce->countries->countries;
	    	$selections = get_option('woocommerce_free_shipping_countries', array());
	    	?><tr class="multi_select_countries">
	            <th scope="row" class="titledesc"><?php _e('Specific Countries', 'woothemes'); ?></th>
	            <td class="forminp">
	            	<div class="multi_select_countries"><ul><?php
	        			if ($countries) foreach ($countries as $key=>$val) :
	            			                    			
	        				echo '<li><label><input type="checkbox" name="woocommerce_free_shipping_countries[]" value="'. $key .'" ';
	        				if (in_array($key, $selections)) echo 'checked="checked"';
	        				echo ' />'. __($val, 'woothemes') .'</label></li>';
	
	            		endforeach;
	       			?></ul></div>
	       		</td>
	       	</tr>
       	</table>
       	<script type="text/javascript">
		jQuery(function() {
			jQuery('select#woocommerce_free_shipping_availability').change(function(){
				if (jQuery(this).val()=="specific") {
					jQuery(this).parent().parent().next('tr.multi_select_countries').show();
				} else {
					jQuery(this).parent().parent().next('tr.multi_select_countries').hide();
				}
			}).change();
		});
		</script>
    	<?php
    }
    
    function process_admin_options() {
   		
   		if(isset($_POST['woocommerce_free_shipping_enabled'])) update_option('woocommerce_free_shipping_enabled', 'yes'); else update_option('woocommerce_free_shipping_enabled', 'no');
   		
   		if(isset($_POST['woocommerce_free_shipping_title'])) update_option('woocommerce_free_shipping_title', woocommerce_clean($_POST['woocommerce_free_shipping_title'])); else delete_option('woocommerce_free_shipping_title');
   		if(isset($_POST['woocommerce_free_shipping_minimum_amount'])) update_option('woocommerce_free_shipping_minimum_amount', woocommerce_clean($_POST['woocommerce_free_shipping_minimum_amount'])); else delete_option('woocommerce_free_shipping_minimum_amount');
   		if(isset($_POST['woocommerce_free_shipping_availability'])) update_option('woocommerce_free_shipping_availability', woocommerce_clean($_POST['woocommerce_free_shipping_availability'])); else delete_option('woocommerce_free_shipping_availability');
	    
	    if (isset($_POST['woocommerce_free_shipping_countries'])) $selected_countries = $_POST['woocommerce_free_shipping_countries']; else $selected_countries = array();
	    update_option('woocommerce_free_shipping_countries', $selected_countries);
   		
    }
    	
}

function add_free_shipping_method( $methods ) {
	$methods[] = 'free_shipping'; return $methods;
}

add_filter('woocommerce_shipping_methods', 'add_free_shipping_method' );