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/**
* Conditional Confirmations (with Merge Tag Support)
* http://gravitywiz.com/2012/08/18/conditional-confirmations/
* 
* Provides the ability to register conditional confirmations. To register a new conditional confirmation
* use the GWConditionalConfirmations::add_conditional_confirmation() function.
* 
* GWConditionalConfirmations::add_conditional_confirmation($form_id, $field_id, $operator, $value, $confirmation);
* 
* @param mixed $form_id The ID of the form for which you would like to register a conditional confirmation.
* @param mixed $field_id The field ID of the field for which you would like to base the confirmation condition.
* @param mixed $operator The operator which will be used to compare the submitted field value against the specified value
*   passed in the $value parameter. Accepted values are "is", "isnot", "greater_than", "less_than", "contains", "starts_with", "ends_with"
* @param mixed $value
* @param mixed $confirmation Accepted values are:
*   array('redirect' => 'http:://yoururl.com')
*   array('page' => 12)
*   'Plain text confirmation!'
* @param $do_init Defaults to true. Will automatically run the init which will trigger the conditional functionality when the 
*   form is submitted. If you would like to init on your own, you can pass false here and call the GWConditionalConfirmation::init()
*   function anytime before the gform_confirmation hook is called.
*/

class GWConditionalConfirmations {
    
    public static $init = false;
    public static $confirmations = array();
    
    public static function init() {
        add_filter('gform_confirmation', array('GWConditionalConfirmations', 'get_conditional_confirmation'), 10, 3);
    }
    
    public static function add_conditional_confirmation($form_id, $field_id, $operator, $value, $confirmation, $do_init = true) {
        
        if(!self::$init && $do_init) {
            GWConditionalConfirmations::init();
            self::$init = true;
        }
        
        if(!isset(self::$confirmations[$form_id]))
            self::$confirmations[$form_id] = array();
        
        $confirmation['gwConditionalLogic'] = array('field_id' => $field_id, 'value' => $value, 'operator' => $operator);
        array_push(self::$confirmations[$form_id], $confirmation);
        
    }
    
    public static function get_conditional_confirmation($confirmation, $form, $lead) {
        
        if(!isset(self::$confirmations[$form['id']]))
            return $confirmation;
        
        foreach(self::$confirmations[$form['id']] as $conf) {
            if(self::is_condition_met($form, $conf['gwConditionalLogic']))
                return self::convert_confirmation($conf, $form, $lead);
        }
        
        return $confirmation;
    }
    
    public static function is_condition_met($form, $condition) {
        
        $field = RGFormsModel::get_field($form, $condition['field_id']);
        $is_visible = !RGFormsModel::is_field_hidden($form, $field, array());
        $field_value = apply_filters('gw_condition_field_value', RGFormsModel::get_field_value($field, array()) );
        $is_value_match = RGFormsModel::is_value_match($field_value, $condition['value'], $condition['operator']);

        return $is_value_match && $is_visible;
    }
    
    public static function convert_confirmation($confirmation, $form, $lead) {
        // if redirect is set, return as is
        if(isset($confirmation['redirect'])) {
            $confirmation['redirect'] = GFCommon::replace_variables(trim($confirmation['redirect']), $form, $lead, true);
            return $confirmation;
        // if page is set, return as redirect with permalink
        } else if(isset($confirmation['page'])) {
            return array('redirect' => get_permalink($confirmation['page']));
        // if nothing else, assume it is text and wrap in the confirmation HTML
        } else {
            return "<div id='preview_form_container'>" . GFCommon::replace_variables($confirmation, $form, $lead, true) . "</div>";
        }
    }
    
}

// example for form ID 7 where the confirmation will redirect the user to http://google.com if the value of field ID 3 is less than 10
GWConditionalConfirmations::add_conditional_confirmation(7, 3, 'less_than', 10, array('redirect' => 'http://google.com'));

// example for form ID 5 where a text confirmation will be displayed if field ID 2 is equal to "Virginia"
GWConditionalConfirmations::add_conditional_confirmation(5, 2, 'is', 'Virginia', 'Confirmed! You are from Virginia!');

// example for form ID 11 where the confirmation will redirect to the WordPress page ID 12 if the value of field ID 4 is greater than 500
GWConditionalConfirmations::add_conditional_confirmation(11, 4, 'greater_than', 500, array('page' => 12));

<?php

/**
* Conditional Confirmations (with Merge Tag Support)
* http://gravitywiz.com/2012/08/18/conditional-confirmations/
* 
* Provides the ability to register conditional confirmations. To register a new conditional confirmation
* use the GWConditionalConfirmations::add_conditional_confirmation() function.
* 
* GWConditionalConfirmations::add_conditional_confirmation($form_id, $field_id, $operator, $value, $confirmation);
* 
* @param mixed $form_id The ID of the form for which you would like to register a conditional confirmation.
* @param mixed $field_id The field ID of the field for which you would like to base the confirmation condition.
* @param mixed $operator The operator which will be used to compare the submitted field value against the specified value
*   passed in the $value parameter. Accepted values are "is", "isnot", "greater_than", "less_than", "contains", "starts_with", "ends_with"
* @param mixed $value
* @param mixed $confirmation Accepted values are:
*   array('redirect' => 'http:://yoururl.com')
*   array('page' => 12)
*   'Plain text confirmation!'
* @param $do_init Defaults to true. Will automatically run the init which will trigger the conditional functionality when the 
*   form is submitted. If you would like to init on your own, you can pass false here and call the GWConditionalConfirmation::init()
*   function anytime before the gform_confirmation hook is called.
*/

class GWConditionalConfirmations {
    
    public static $init = false;
    public static $confirmations = array();
    
    public static function init() {
        add_filter('gform_confirmation', array( __class__, 'get_conditional_confirmation'), 10, 3);
    }
    
    public static function add_conditional_confirmation($form_id, $field_id, $operator, $value, $confirmation, $do_init = true) {
        
        if(!self::$init && $do_init) {
            GWConditionalConfirmations::init();
            self::$init = true;
        }
        
        if(!isset(self::$confirmations[$form_id]))
            self::$confirmations[$form_id] = array();
        
        $confirmation['gwConditionalLogic'] = array('field_id' => $field_id, 'value' => $value, 'operator' => $operator);
        array_push(self::$confirmations[$form_id], $confirmation);
        
    }
    
    public static function get_conditional_confirmation($confirmation, $form, $lead) {
        
        if(!isset(self::$confirmations[$form['id']]))
            return $confirmation;
        
        foreach(self::$confirmations[$form['id']] as $conf) {
            if(self::is_condition_met($form, $conf['gwConditionalLogic']))
                return self::convert_confirmation($conf, $form, $lead);
        }
        
        return $confirmation;
    }
    
    public static function is_condition_met($form, $condition) {
        
        $field = RGFormsModel::get_field($form, $condition['field_id']);
        $is_visible = !RGFormsModel::is_field_hidden($form, $field, array());
        $field_value = apply_filters('gw_condition_field_value', RGFormsModel::get_field_value($field, array()) );
        $is_value_match = RGFormsModel::is_value_match($field_value, $condition['value'], $condition['operator']);

        return $is_value_match && $is_visible;
    }
    
    public static function convert_confirmation($confirmation, $form, $lead) {
        // if redirect is set, return as is
        if(isset($confirmation['redirect'])) {
            $confirmation['redirect'] = GFCommon::replace_variables( trim( $confirmation['redirect'] ), $form, $lead, true );
            return $confirmation;
        // if page is set, return as redirect with permalink
        } else if(isset($confirmation['page'])) {
            return array('redirect' => get_permalink($confirmation['page']));
        // if nothing else, assume it is text and wrap in the confirmation HTML
        } else {
            return "<div id='preview_form_container'>" . GFCommon::replace_variables($confirmation, $form, $lead, true) . "</div>";
        }
    }
    
}

// example for form ID 7 where the confirmation will redirect the user to http://google.com if the value of field ID 3 is less than 10
GWConditionalConfirmations::add_conditional_confirmation(7, 3, 'less_than', 10, array('redirect' => 'http://google.com'));

// example for form ID 5 where a text confirmation will be displayed if field ID 2 is equal to "Virginia"
GWConditionalConfirmations::add_conditional_confirmation(5, 2, 'is', 'Virginia', 'Confirmed! You are from Virginia!');

// example for form ID 11 where the confirmation will redirect to the WordPress page ID 12 if the value of field ID 4 is greater than 500
GWConditionalConfirmations::add_conditional_confirmation(11, 4, 'greater_than', 500, array('page' => 12));