Flexicharge + Coupon Problems

Works great! N.B. - only works if Flexicharge is set before Payment in the Screen Order section.

A clarification for other interested parties on how to properly hack this:

Function should look like this:

/**
 * Use checkoutapi to calculate charges, each method has it's own checkout
 * function
 */
function flexicharge_checkoutapi(&$txn, $op, $arg3 = null, $arg4 = null) {
  if ($txn == 'flexicharge') {
    return true;
  }
 
 //only run once (fix double charge with coupons) - jmd
  if($txn->flexicharge_applied) {
    return;
  }

  // cart_get_items() doesn't do a full node load, so we don't have
  // access to shipping data and therefore need to manually add
  // flexicharge data here.
  // NOTE: this is done like shipping.module
  if (isset($txn->items)) {
    foreach (array_keys($txn->items) as $nid) {
      flexicharge_nodeapi($txn->items[$nid], 'load', NULL);
    }
  }
  switch ($op) {
    case 'review':

      // Get saved charges from database.
      $charges = _flexicharge_load_charges();
      
      // Remove charges that does not apply by PRODUCT.
      foreach ($charges as $charge) {
        // If there is a product filter on the charge.
        if (!empty($charge->ptypes)) {
          // Check if any ptypes match the filter.
          foreach ($txn->items as $item) {
            if (empty($charge->ptypes[$item->ptype])) {
              unset($charges[$charge->chid]);
              break;
            }
          }
        }
      }

      global $user;
      // Remove charges that does not apply by ROLE.
      foreach ($charges as $charge) {
        // If there is a role filter on the charge.
        if (!empty($charge->roles)) {
          // Check if any roles match the filter.
          foreach ($user->roles as $role_id => $role) {
            if (empty($charge->roles[$role_id])) {
              unset($charges[$charge->chid]);
            }
          }
        }
      }
      // Call this to include() the method files.
      _flexicharge_partners();

      $return = array();
      $weight_offset = 1000; // Very heavy, we want to appear below all other charges.

      foreach ($charges as $charge) {
        // this is the operation we normally want for a misc charge
        $f = $charge->provider .'_flexicharge_review';
        if (function_exists($f)) {
          $charge_data = $f($txn, $charge);
        }
        // Note, we give flexicharge a heavy weight until it can be
        // properly integrated into the order of other misc charges
        // because some misc charges could be based on other charges.

        if (is_array($charge_data)) {
          $charge_data['weight'] += $weight_offset;
          $txn->misc[] = (object)$charge_data;
        }
        elseif ($charge_data) {
          $return[] = $charge_data;
        }
      }

//charges have been calculated - do not run again; -jmd
  $txn->flexicharge_applied = true;

      break;

    case 'review_submit':

      break;

  }

}

This is an awkward solution, but I haven't had any luck with the 'already_added' element....

function custom_flexicharge_review(&$txn, $charge) {
  switch ($charge->method) {
      case 'general':
         $misc = array(
            'type' => 'fl_'. $charge->chid,
            'description' => $charge->display,
            'operator' => $charge->operator,
            'rate' => $charge->rate,
            'subtotal_before' => $charge->subtotal_before,
            'subtotal_after' => $charge->subtotal_before,
            'already_added' => $charge->already_added,
            'weight' => $charge->position,
            'method' => $charge->method,
            'callback' => 'general_custom_flexicharge_calculate',
          );
      break;
  }
  
  // only process this once.
  if (is_array($txn->misc)) {
    foreach ($txn->misc as $flexi) {
      if ($flexi->type == 'fl_'. $charge->chid) {
	    return;  // already processed, do nothing
      }
    }
  }
  return $misc; // add flexicharge
}