Programmatically create auto generated coupon code

Question

Based on other stackoverflow posts, I've been able to use the following code to programmatically generate individual shopping cart price rule coupons in Magento.

How can I programmatically call the "Auto Generate Coupon" feature to create 100 unique coupons for each price rule I make? Thanks!

$coupon = Mage::getModel('salesrule/rule');
$coupon->setName($_coupon['name'])
       ->setDescription('this is a description')
       ->setFromDate(date('Y-m-d'))
       ->setCouponType(2)
       ->setCouponCode($_coupon['code'])
       ->setUsesPerCoupon(1000)
       ->setUsesPerCustomer(100)
       ->setCustomerGroupIds(array(1)) //an array of customer groupids
       ->setIsActive(1)
       //serialized conditions.  the following examples are empty
       ->setConditionsSerialized('a:6:{s:4:"type";s:32:"salesrule/rule_condition_combine";s:9:"attribute";N;s:8:"operator";N;s:5:"value";s:1:"1";s:18:"is_value_processed";N;s:10:"aggregator";s:3:"all";}')
       ->setActionsSerialized('a:6:{s:4:"type";s:40:"salesrule/rule_condition_product_combine";s:9:"attribute";N;s:8:"operator";N;s:5:"value";s:1:"1";s:18:"is_value_processed";N;s:10:"aggregator";s:3:"all";}')
       ->setStopRulesProcessing(0)
       ->setIsAdvanced(1)
       ->setProductIds('')
       ->setSortOrder(0)
       ->setSimpleAction('by_percent')
       ->setDiscountAmount(100)
       ->setDiscountQty(null)
       ->setDiscountStep('0')
       ->setSimpleFreeShipping('0')
       ->setApplyToShipping('0')
       ->setIsRss(0)
       ->setWebsiteIds(array(1));      
$coupon->save();

For instance, this one price rule might have a whole list of Auto-Generated Coupon Codes (htgf-7774, htgf-2345, etc) using the function that is available when manually creating price rules in the admin panel.

EDIT:

I've gotten closer, using the following code. Still don't know how to specifically assign the auto generation pattern

->setName('Name')
->setDescription('this is a description')
->setFromDate('2013-03-06')
->setToDate(NULL)
->setUsesPerCustomer('100')
->setIsActive('1')
->setConditionsSerialized('a:6:{s:4:"type";s:32:"salesrule/rule_condition_combine";s:9:"attribute";N;s:8:"operator";N;s:5:"value";s:1:"1";s:18:"is_value_processed";N;s:10:"aggregator";s:3:"all";}')
->setActionsSerialized('a:6:{s:4:"type";s:40:"salesrule/rule_condition_product_combine";s:9:"attribute";N;s:8:"operator";N;s:5:"value";s:1:"1";s:18:"is_value_processed";N;s:10:"aggregator";s:3:"all";}')
->setStopRulesProcessing('0')
->setIsAdvanced('1')
->setProductIds(NULL)
->setSortOrder('0')
->setSimpleAction('by_percent')
->setDiscountAmount('100.0000')
->setDiscountQty(NULL)
->setDiscountStep('0')
->setSimpleFreeShipping('0')
->setApplyToShipping('0')
->setTimesUsed('1')
->setIsRss('0')
->setCouponType('2')
->setUseAutoGeneration('1')
->setUsesPerCoupon('1000')
->setCustomerGroupIds(array('1',))
->setWebsiteIds(array('1',))
->setCouponCode(NULL)

Answer 1

Thanks to a nifty post I found while googling this (http://fragmentedthought.com/fragments/programatically-creating-sales-rule-coupon-code), I answered my own question:

// Get the rule in question
$rule = Mage::getModel('salesrule/rule')->load(21); //21 = ID of coupon in question

// Define a coupon code generator model instance
// Look at Mage_SalesRule_Model_Coupon_Massgenerator for options
$generator = Mage::getModel('salesrule/coupon_massgenerator');

$parameters = array(
    'count'=>5,
    'format'=>'alphanumeric',
    'dash_every_x_characters'=>4,
    'prefix'=>'ABCD-EFGH-',
    'suffix'=>'-WXYZ',
    'length'=>8
);

if( !empty($parameters['format']) ){
  switch( strtolower($parameters['format']) ){
    case 'alphanumeric':
    case 'alphanum':
      $generator->setFormat( Mage_SalesRule_Helper_Coupon::COUPON_FORMAT_ALPHANUMERIC );
      break;
    case 'alphabetical':
    case 'alpha':
      $generator->setFormat( Mage_SalesRule_Helper_Coupon::COUPON_FORMAT_ALPHABETICAL );
      break;
    case 'numeric':
    case 'num':
      $generator->setFormat( Mage_SalesRule_Helper_Coupon::COUPON_FORMAT_NUMERIC );
      break;
  }
}

$generator->setDash( !empty($parameters['dash_every_x_characters'])? (int) $parameters['dash_every_x_characters'] : 0);
$generator->setLength( !empty($parameters['length'])? (int) $parameters['length'] : 6);
$generator->setPrefix( !empty($parameters['prefix'])? $parameters['prefix'] : '');
$generator->setSuffix( !empty($parameters['suffix'])? $parameters['suffix'] : '');

// Set the generator, and coupon type so it's able to generate
$rule->setCouponCodeGenerator($generator);
$rule->setCouponType( Mage_SalesRule_Model_Rule::COUPON_TYPE_AUTO );

// Get as many coupons as you required
$count = !empty($parameters['count'])? (int) $parameters['count'] : 1;
$codes = array();
for( $i = 0; $i < $count; $i++ ){
  $coupon = $rule->acquireCoupon();
  $code = $coupon->getCode();
  $codes[] = $code;
}
return $codes;

This successfully generated the following codes:

ABCD-EFGH-ZC6V-ZJWD-WXYZ
ABCD-EFGH-4XMX-353L-WXYZ
ABCD-EFGH-XCJB-5GQI-WXYZ
ABCD-EFGH-UEAO-L1NJ-WXYZ
ABCD-EFGH-59B3-50T2-WXYZ