//Gravity forms - limit entries

functions.php

//Gravity forms - limite de entradas 

class GWLimitBySum {
 
    private $_args;
 
    function __construct($args) {
 
        $this->_args = wp_parse_args($args, array(
            'form_id' => false,
            'field_id' => false,
            'limit' => 20,
            'limit_message' => __('Sorry, this item is sold out.'),
            'validation_message' => __('You ordered %1$s of this item. There are only %2$s of this item left.'),
            'approved_payments_only' => false,
            'hide_form' => false
        ));
 
        $this->_args['input_id'] = $this->_args['field_id'];
        extract($this->_args);
 
        add_filter("gform_pre_render_$form_id", array(&$this, 'limit_by_field_values'));
        add_filter("gform_validation_$form_id", array(&$this, 'limit_by_field_values_validation'));
    
        // add 'sum' action for [gravityforms] shortcode
        add_filter( 'gform_shortcode_sum', array( $this, 'shortcode_sum' ), 10, 2 );
	add_filter( 'gform_shortcode_remaining', array( $this, 'shortcode_remaining' ), 10, 2 ); 
	
        if($approved_payments_only)
            add_filter('gwlimitbysum_query', array(&$this, 'limit_by_approved_only'));
 
    }
 
    public function limit_by_field_values($form) {
 
        $sum = self::get_field_values_sum($form['id'], $this->_args['input_id']);
        if($sum < $this->_args['limit'])
            return $form;
 
        if($this->_args['hide_form']) {
            add_filter('gform_get_form_filter', create_function('', 'return "' . $this->_args['limit_message'] . '";'));
        } else {
            add_filter('gform_field_input', array(&$this, 'hide_field'), 10, 2);
        }
 
        return $form;
    }
 
    public function limit_by_field_values_validation($validation_result) {
 
        extract($this->_args);
 
        $form = $validation_result['form'];
        $exceeded_limit = false;
 
        foreach($form['fields'] as &$field) {
 
            if($field['id'] != intval($input_id))
                continue;
 
            $requested_value = rgpost("input_" . str_replace('.', '_', $input_id));
            $field_sum = self::get_field_values_sum($form['id'], $input_id);
 
            if($field_sum + $requested_value <= $limit)
                continue;
 
            $exceeded_limit = true;
            $number_left = $limit - $field_sum >= 0 ? $limit - $field_sum : 0;
 
            $field['failed_validation'] = true;
            $field['validation_message'] = sprintf($validation_message, $requested_value, $number_left);
 
        }
 
        $validation_result['form'] = $form;
        $validation_result['is_valid'] = !$validation_result['is_valid'] ? false : !$exceeded_limit;
 
        return $validation_result;
    }
 
    public function hide_field($field_content, $field) {
 
        if($field['id'] == intval($this->_args['input_id']))
            return "<div class=\"ginput_container\">{$this->_args['limit_message']}</div>";
 
        return $field_content;
    }
 
    public static function get_field_values_sum($form_id, $input_id) {
        global $wpdb;
 
        $query = apply_filters( 'gwlimitbysum_query', array(
            'select' => 'SELECT sum( ld.value )',
            'from' => "FROM {$wpdb->prefix}rg_lead_detail ld",
            'join' => '',
            'where' => $wpdb->prepare( "WHERE ld.form_id = %d AND CAST( ld.field_number as unsigned ) = %d", $form_id, $input_id )
        ), $form_id, $input_id );
 
        $wpdb->show_errors();
 
        $sql = implode( ' ', $query );
        $result = $wpdb->get_var( $sql );
 
        return intval( $result );
    }
 
    public static function limit_by_approved_only( $query ) {
        global $wpdb;
        $query['from'] .= " INNER JOIN {$wpdb->prefix}rg_lead l ON l.id = ld.lead_id";
        $query['where'] .= ' AND l.payment_status = \'Approved\'';
        return $query;
    }
 
	public function shortcode_sum( $output, $atts ) {
	
		$atts = shortcode_atts( array(
			'id' => false,
			'input_id' => false
		), $atts );
	
		extract( $atts ); // gives us $id, $input_id
	
		return intval( self::get_field_values_sum( $id, $input_id ) );
	}
 
	public function shortcode_remaining( $output, $atts ) {
 
		$atts = shortcode_atts( array(
			'id' => false,
			'input_id' => false,
			'limit'    => false
		), $atts );
 
		extract( $atts ); // gives us $id, $input_id
 
		$remaining = $limit - intval( self::get_field_values_sum( $id, $input_id ) );
 
		return max( 0, $remaining );
	}
 
}
 
# Configuration
 
new GWLimitBySum( array(
    'form_id'                => 5,
    'field_id'               => 5.70,
    'limit'                  => 70,
    'limit_message'          => '<h3>Desculpe, acabaram os ingressos.</h3>',
    'validation_message'     => 'Você selecionou %1$s ingressos, restam ainda %2$s ingressos à venda.',
    'approved_payments_only' => true,
    'hide_form'              => true
) );
new GWLimitBySum( array(
    'form_id'                => 5,
    'field_id'               => 8.40,
    'limit'                  => 40,
    'limit_message'          => '<h3>Desculpe, acabaram os ingressos para crianças.</h3>',
    'validation_message'     => 'Você selecionou %1$s ingressos, restam ainda %2$s ingressos à venda.',
    'approved_payments_only' => true,
    'hide_form'              => false
) );