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<?php
/**
* Gravity Perks: GP Limit Choices // Share Limits Across Multiple Fields
*
* Adds support for specifying groups of fields which share the same limit. For example, if you had two fields with a
* limit of 10, selections from both fields would contribute to that limit.
*
* @author    David Smith <david@gravitywiz.com>
* @license   GPL-2.0+
* @link      http://gravitywiz.com/gravity-perks/
* @copyright 2013 Gravity Wiz
*/
class GWLimitChoicesSharedLimits {
    
    function __construct( $args ) {
        
        extract( wp_parse_args( $args, array(
            'form_id' => false,
            'field_groups' => array()
            ) ) );
        
        $this->form_id = $form_id;
        $this->field_groups = $field_groups;
        
        add_filter( "gwlc_choice_counts_query_{$form_id}", array( $this, 'modify_choice_counts_query' ), 10, 2 );
        
    }
    
    function modify_choice_counts_query( $query, $field ) {
    
        $form = RGFormsModel::get_form_meta( $field['formId'] );
        $fields = array();
        
        foreach( $this->field_groups as $field_group ) {
            
            if( !in_array( $field['id'], $field_group ) )
                continue;
            
            $where = explode( 'AND ', $query['where'] );
            
            foreach( $where as &$where_clause ) {
                if( strpos( $where_clause, 'CAST(ld.field_number as unsigned)' ) !== false )
                    $where_clause = 'CAST(ld.field_number as unsigned) IN ( ' . implode( ', ', $field_group ) . ' )';
            }
            
            $query['where'] = implode( 'AND ', $where );
            
        }
        
        return $query;
    }
    
}

new GWLimitChoicesSharedLimits( array( 
    'form_id' => 16, 
    'field_groups' => array(
        array( 12, 20 )
        ) 
    ) );