Debug Oriented Programming или печаль в глазах Интегратора

public function isApplicable()
{
    $p = $this->getProduct();
    if (!$p) {
        return false;
    }
    // has image for the current mode
    if (!$this->getValue('img'))
        return false;
    $now = Mage::getModel('core/date')->date();
    if ($this->getDateRangeEnabled() && ($now < $this->getFromDate() || $now > $this->getToDate())) {
        return false;
    }
    // individula products logic
    $inArray = in_array($p->getSku(), explode(',', $this->getIncludeSku()));
    if (!$p->getSku())
        $inArray = false;
    // include skus
    if (0 == $this->getIncludeType() && $inArray)
        return true;
    // exclude skus
    if (1 == $this->getIncludeType() && $inArray)
        return false;
    // use for skus only
    if (2 == $this->getIncludeType())
        return $inArray;

    if ($this->getPriceRangeEnabled()) {
        switch ($this->getByPrice()) {
            case '0': // Base Price
                $price = $p->getPrice();
                break;
            case '1': // Special Price
                $price = $p->getSpecialPrice(); // or $this->_info['special_price']
                break;
            case '2': // Final Price
                $price = Mage::helper('tax')->getPrice($p, $p->getFinalPrice());
                break;
            case '3': // Final Price Incl Tax
                $price = Mage::helper('tax')->getPrice($p, $p->getFinalPrice(), true);
                break;
            case '4': // Starting from Price
                $price = $this->_getMinimalPrice($p);
                break;
            case '5': // Starting to Price
                $price = $this->_getMaximalPrice($p);
                break;
        }
        if ($p->getTypeId() == 'bundle'){
            $priceMin = $p->getMinPrice();
            $priceMax = $p->getMaxPrice();
            if ($priceMin < $this->getFromPrice() && $priceMax > $this->getToPrice()) {
                return false;
            }
        }
        else if ($price < $this->getFromPrice() || $price > $this->getToPrice()) {
            return false;
        }
    }
    $attrCode = $this->getAttrCode();
    if ($attrCode) {
        if (!array_key_exists($attrCode, $p->getData())) { // has attribute condition
            return false;
        }
        // compatibility with the `Amasty: Custom Stock Status` extension
        // if the `Use Quantity Ranges Based Stock Status` property setted to `Yes`
        // so the value of the `Custom Stock Status` is dynamic
        // and setted to the product value is not used
        if (('custom_stock_status' === $attrCode) && (Mage::helper('core')->isModuleEnabled('Amasty_Stockstatus'))) {
            if ($this->getAttrValue() != Mage::helper('amstockstatus')->getCustomStockStatusId($p)) {
                return false;
            }
        } elseif ($this->getAttrValue()) {
            $v = $p->getData($attrCode);
            if (preg_match('/^[0-9,]+$/', $v)){
                if (!in_array($this->getAttrValue(), explode(',', $v))){
                    return false;
                }
            }
            elseif ($v != $this->getAttrValue()){
                return false;
            }
        } elseif (!$p->getData($attrCode)) { // sometimes needed for has attribute condition too
            return false;
        }
    }
    $catIds = $this->getCategory();
    if ($catIds) {
        $ids = $p->getCategoryIds();
        if (!is_array($ids))
            return false;
        $found = false;
        foreach (explode(',', $catIds) as $catId) {
            if (in_array($catId, $ids))
                $found = true;
        }
        if (!$found)
            return false;
    }
    $stockStatus = $this->getStockStatus();
    if ($stockStatus){
        $inStock = $p->getStockItem()->getIsInStock() ? 2 : 1;
        if ($inStock != $stockStatus)
            return false;
    }
    if ($this->getIsNew()){
        $isNew = $this->_isNew($p) ? 2 : 1;
        if ($this->getIsNew() != $isNew)
            return false;
    }
    if ($this->getIsSale()){
        $isSale = $this->_isSale() ? 2 : 1;
        if ($this->getIsSale() != $isSale)
            return false;
    }
    if ($this->getCustomerGroupEnabled() && ('' === $this->getCustomerGroups() || // need this condition, because in_array returns true for NOT LOGGED IN customers
        (!in_array(Mage::getSingleton('customer/session')->getCustomerGroupId(), explode(',', $this->getCustomerGroups())))))
        return false;
    // finally ...
    return true;
}