<?

AddEventHandler("iblock", "OnAfterIBlockElementUpdate", "DoIBlockAfterSave");
AddEventHandler("iblock", "OnAfterIBlockElementAdd", "DoIBlockAfterSave");
AddEventHandler("catalog", "OnPriceAdd", "DoIBlockAfterSave");
AddEventHandler("catalog", "OnPriceUpdate", "DoIBlockAfterSave");

function DoIBlockAfterSave($arg1, $arg2 = false){

	global $USER;
	$ELEMENT_ID = false;
	$IBLOCK_ID = false;
	$OFFERS_IBLOCK_ID = false;
	$OFFERS_PROPERTY_ID = false;
	$BX_SITE_ID = "s1"; //you site id

	if (CModule::IncludeModule('currency'))
		$strDefaultCurrency = CCurrency::GetBaseCurrency();
	//Check for catalog event

	if(is_array($arg2) && $arg2["PRODUCT_ID"] > 0){
		//Get iblock element
		$rsPriceElement = CIBlockElement::GetList(
			array(),
			array(
				"ID" => $arg2["PRODUCT_ID"],
			),
			false,
			false,
			array("ID", "IBLOCK_ID")
		);
		if($arPriceElement = $rsPriceElement->Fetch()){
			$arCatalog = CCatalog::GetByID($arPriceElement["IBLOCK_ID"]);
			if(is_array($arCatalog)){
				//Check if it is offers iblock
				if($arCatalog["OFFERS"] == "Y"){
					//Find product element
					$rsElement = CIBlockElement::GetProperty(
						$arPriceElement["IBLOCK_ID"],
						$arPriceElement["ID"],
						"sort",
						"asc",
						array("ID" => $arCatalog["SKU_PROPERTY_ID"])
					);
					$arElement = $rsElement->Fetch();
					if($arElement && $arElement["VALUE"] > 0){
						$ELEMENT_ID = $arElement["VALUE"];
						$IBLOCK_ID = $arCatalog["PRODUCT_IBLOCK_ID"];
						$OFFERS_IBLOCK_ID = $arCatalog["IBLOCK_ID"];
						$OFFERS_PROPERTY_ID = $arCatalog["SKU_PROPERTY_ID"];
					}
				}
				//or iblock which has offers
				elseif($arCatalog["OFFERS_IBLOCK_ID"] > 0){
					$ELEMENT_ID = $arPriceElement["ID"];
					$IBLOCK_ID = $arPriceElement["IBLOCK_ID"];
					$OFFERS_IBLOCK_ID = $arCatalog["OFFERS_IBLOCK_ID"];
					$OFFERS_PROPERTY_ID = $arCatalog["OFFERS_PROPERTY_ID"];
				}
				//or it's regular catalog
				else{
					$ELEMENT_ID = $arPriceElement["ID"];
					$IBLOCK_ID = $arPriceElement["IBLOCK_ID"];
					$OFFERS_IBLOCK_ID = false;
					$OFFERS_PROPERTY_ID = false;
				}
			}
		}
	}
	//Check for iblock event
	elseif(is_array($arg1) && $arg1["ID"] > 0 && $arg1["IBLOCK_ID"] > 0){
		//Check if iblock has offers
		$arOffers = CIBlockPriceTools::GetOffersIBlock($arg1["IBLOCK_ID"]);
		if(is_array($arOffers)){
			$ELEMENT_ID = $arg1["ID"];
			$IBLOCK_ID = $arg1["IBLOCK_ID"];
			$OFFERS_IBLOCK_ID = $arOffers["OFFERS_IBLOCK_ID"];
			$OFFERS_PROPERTY_ID = $arOffers["OFFERS_PROPERTY_ID"];
		}
	}

	if($ELEMENT_ID){
		static $arPropCache = array();
		if(!array_key_exists($IBLOCK_ID, $arPropCache)){
			//Check for MINIMAL_PRICE property
			$rsProperty = CIBlockProperty::GetByID("MINIMUM_PRICE", $IBLOCK_ID);
			$arProperty = $rsProperty->Fetch();
			if($arProperty)
				$arPropCache[$IBLOCK_ID] = $arProperty["ID"];
			else
				$arPropCache[$IBLOCK_ID] = false;
		}

		if($arPropCache[$IBLOCK_ID]){
			//Compose elements filter
			if($OFFERS_IBLOCK_ID){
				$rsOffers = CIBlockElement::GetList(
					array(),
					array(
						"IBLOCK_ID" => $OFFERS_IBLOCK_ID,
						"PROPERTY_".$OFFERS_PROPERTY_ID => $ELEMENT_ID,
					),
					false,
					false,
					array("ID")
				);
				while($arOffer = $rsOffers->Fetch())
					$arProductID[] = $arOffer["ID"];

				if (!is_array($arProductID))
					$arProductID = array($ELEMENT_ID);
			}
			else
				$arProductID = array($ELEMENT_ID);

			$minPrice = false;
			$maxPrice = false;

			foreach ($arProductID as $productID) {

				$arDiscountPrice = CCatalogProduct::GetOptimalPrice($productID, 1, $USER->GetUserGroupArray(), false, false, $BX_SITE_ID);

				if (CModule::IncludeModule('currency') && $strDefaultCurrency != $arDiscountPrice['RESULT_PRICE']['CURRENCY'])
					$arDiscountPrice['DISCOUNT_PRICE'] = CCurrencyRates::ConvertCurrency($arDiscountPrice['DISCOUNT_PRICE'], $arDiscountPrice['RESULT_PRICE']["CURRENCY"], $strDefaultCurrency);

				$PRICE = $arDiscountPrice['DISCOUNT_PRICE'];

				if($minPrice === false || $minPrice > $PRICE)
					$minPrice = $PRICE;

				if($maxPrice === false || $maxPrice < $PRICE)
					$maxPrice = $PRICE;
			}

			//Save found minimal price into property
			if($minPrice !== false){
				CIBlockElement::SetPropertyValuesEx(
					$ELEMENT_ID,
					$IBLOCK_ID,
					array(
						"MINIMUM_PRICE" => $minPrice,
						"MAXIMUM_PRICE" => $maxPrice,
					)
				);
			}
		}
	}
}
?>

<?$BASE_PRICE = CCatalogGroup::GetBaseGroup();?>
<?$arSortFields = array(
  "SHOWS" => array(
    "ORDER"=> "DESC",
    "CODE" => "SHOWS",
    "NAME" => GetMessage("CATALOG_SORT_FIELD_SHOWS")
  ),  
  "NAME" => array( // параметр в url
    "ORDER"=> "ASC", //в возрастающем порядке
    "CODE" => "NAME", // Код поля для сортировки
    "NAME" => GetMessage("CATALOG_SORT_FIELD_NAME") // имя для вывода в публичной части, редактировать в (/lang/ru/section.php)
  ),
  "PRICE_ASC"=> array(
    "ORDER"=> "ASC",
    "CODE" => "PROPERTY_MINIMUM_PRICE",  // изменен для сортировки по ТП
    "NAME" => GetMessage("CATALOG_SORT_FIELD_PRICE_ASC")
  ),
  "PRICE_DESC" => array(
    "ORDER"=> "DESC",
    "CODE" => "PROPERTY_MAXIMUM_PRICE", // изменен для сортировки по ТП
    "NAME" => GetMessage("CATALOG_SORT_FIELD_PRICE_DESC")
  )
);?>