ContactsApiHelper.php

<?php
require_once('modules/Contacts/ContactsApiHelper.php');

// Since the ContactsApiHelper exists, we'll extend it
// If it didn't we would just extend the SugarBeanApiHelper
class CustomContactsApiHelper extends ContactsApiHelper
{
    // Mimic the SugarBeanApiHelper->formatForApi() class
    public function formatForApi(SugarBean $bean, array $fieldList = array(), array $options = array())
    {
        // First off, call the parent class
        $data = parent::formatForApi($bean, $fieldList, $options);

        // Make sure they requested the top_opp field, or no field restriction at all
        if (empty($fieldList) || in_array('top_opp', $fieldList) ) {
            // Build a list of the fields we care about
            static $oppFields = array(
                'id',
                'name',
                'currency_id',
                'amount',
                'date_closed',
            );

            // Make sure we don't populate this some other way
            if (!isset($bean->top_opp) && !empty($bean->id)) {
                // Get a seed for Opportunities
                $oppSeed = BeanFactory::newBean('Opportunities');
                $q = new SugarQuery();
                // Set the from bean
                $q->from($oppSeed);
                // Join in using the 'contacts' link field
                $contactJoin = $q->join('contacts');
                // Limit our join to just the contact we care about
                $q->where()->equals($contactJoin->joinName().'.id', $bean->id);
                $q->where()->notIn('sales_stage', array('Closed Lost', 'Closed Won'));
                // Sort by the "usdollar" amount, the normal amount field could be in
                // different currencies and so the sorting will be all wrong.
                $q->orderBy('amount_usdollar DESC');
                // Just get the top opportunity
                $q->limit(1);
                
                // Use fetchFromQuery and pass in the fields we care about
                $beans = $oppSeed->fetchFromQuery($q, $oppFields);
                
                if (count($beans) > 0) {
                    // Even though we had a limit of 1, fetchFromQuery still returns an array
                    // They are indexed by ID, so let's just fetch the first and only one
                    $bean->top_opp = array_pop($beans);
                } else {
                    // Flag it so we know we tried to set it, there just wasn't anything there
                    $bean->top_opp = null;
                }
            }
             
            $data['top_opp'] = array();
            if ($bean->top_opp != null) {
                // getHelper will get us the helper we want
                $data['top_opp'] = ApiHelper::getHelper($GLOBALS['service'], $bean->top_opp)
                    ->formatForApi($bean->top_opp, $oppFields);
            }
        }

        // formatForApi returns the bean formatted as a hash in API format
        return $data;
    }
}