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<?php
/**
 * Plugin Name: WooCommerce Display Currency Code in Currency Symbol
 * Plugin URI: https://gist.github.com/BFTrick/10681832
 * Description: Add the currency code to the currency symbol in WooCommerce. Ex. USD $.
 * Author: Patrick Rauland
 * Author URI: http://patrickrauland.com/
 * Version: 1.0
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 *
 */
function patricks_currency_symbol( $currency_symbol, $currency ) {

    switch( $currency ) {
        case 'USD':
            $currency_symbol = 'USD $';
            break;
        case 'NZD':
            $currency_symbol = 'NZD $';
            break;
        case 'AUD':
            $currency_symbol = 'AUD $';
            break;
    }

    return $currency_symbol;

}
add_filter('woocommerce_currency_symbol', 'patricks_currency_symbol', 30, 2);