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<?php
/**
* Format Fields as Currency via jQuery
* http://gravitywiz.com/format-field-as-currency/
*/
class GWFormatMoney {

    /**
    * Stores a copy of the original field values so once the money-formatted numbers have been cleaned for validation
    * they can be restored after being validated.
    *
    */
    var $_field_values = array();

    function __construct() {

        add_filter( 'gform_pre_render', array( $this, 'format_money_js' ) );
        add_filter( 'gform_pre_validation', array( $this, 'clean_value_for_number_fields' ) );
        add_filter( 'gform_validation', array( $this, 'restore_value_for_number_fields' ) );
        add_action( 'gform_get_field_value', array( $this, 'format_money' ), 10, 3 );

    }

    function format_money_js($form) {

        $this->enqueue_gravityforms_js();

        $script = '(function($){' .
            '$(".gf_money input").each( function() { ' .
                '$(this).val( gformFormatMoney( $(this).val() ) ); ' .
            '}).change( function( event ) { ' .
                '$(this).val( gformFormatMoney( $(this).val() ) ); ' .
            '}); ' .
            'gform.addFilter( "gform_calculation_format_result", "gwMaybeFormatMoney" ); ' .
            'window.gwMaybeFormatMoney = function( returnVal, origResult, formulaField, formId ) { ' .
                'var field = jQuery("#field_" + formId + "_" + formulaField.field_id); ' .
                'return field.hasClass( "gf_money" ) ? gformFormatMoney( origResult ) : returnVal; ' .
            '} ' .
        '})(jQuery);';

        GFFormDisplay::add_init_script( $form['id'], 'format_money', GFFormDisplay::ON_PAGE_RENDER, $script );

        return $form;
    }

    function format_money( $value, $lead, $field ) {

        $css_classes = explode( ' ', rgar( $field, 'cssClass' ) );
        if( ! in_array( 'gf_money', $css_classes ) )
            return $value;

        require_once( GFCommon::get_base_path() . '/currency.php' );
        $currency = new RGCurrency( GFCommon::get_currency() );
        $value = $currency->to_money( $value );

        return $value;
    }

    function clean_value_for_number_fields( $form ) {

        foreach( $form['fields'] as $field ) {

            $is_number_field = GFFormsModel::get_input_type( $field ) == 'number';
            $has_gf_money_class = in_array( 'gf_money', explode( ' ', rgar( $field, 'cssClass' ) ) );

            if( ! $is_number_field || ! $has_gf_money_class )
                continue;

            $value = $_POST["input_{$field['id']}"];
            if( ! $value )
                continue;

            // save original value to be restored later
            $this->_field_values[$field['id']] = $value;

            require_once(GFCommon::get_base_path() . '/currency.php');
            $currency = new RGCurrency(GFCommon::get_currency());
            $_POST["input_{$field['id']}"] = $currency->to_number( $value );

        }

        return $form;
    }

    function restore_value_for_number_fields( $validation_result ) {

        foreach( $validation_result['form']['fields'] as $field ) {

            if( ! isset( $this->_field_values[$field['id']] ) )
                continue;

            $value = $this->_field_values[$field['id']];

            // @REMOVE: since the original value will already be in the money format, no need to reformat here
            //          leaving in place for a few weeks to ensure no issues come up with the removal
            // require_once(GFCommon::get_base_path() . '/currency.php');
            // $currency = new RGCurrency(GFCommon::get_currency());
            // $currency->to_money( $value );
            $_POST["input_{$field['id']}"] = $value;

        }

        return $validation_result;
    }

    function enqueue_gravityforms_js() {

        $has_proper_support = version_compare( GFCommon::$version, '1.8.dev4', '>=' );
        $enqueue_script = $has_proper_support ? 'gform_gravityforms' : 'gforms_gravityforms';

        if( ! wp_script_is( $enqueue_script ) )
            wp_enqueue_script( $enqueue_script );

    }

}

new GWFormatMoney();