/**
* WooCommerce Stock Functions
*
* Functions used to manage product stock levels.
*
* @package WooCommerce\Functions
* @version 3.4.0
*/
defined( 'ABSPATH' ) || exit;
use Automattic\WooCommerce\Checkout\Helpers\ReserveStock;
use Automattic\WooCommerce\Enums\ProductType;
/**
* Update a product's stock amount.
*
* Uses queries rather than update_post_meta so we can do this in one query (to avoid stock issues).
*
* @since 3.0.0 this supports set, increase and decrease.
*
* @param int|WC_Product $product Product ID or product instance.
* @param int|null $stock_quantity Stock quantity.
* @param string $operation Type of operation, allows 'set', 'increase' and 'decrease'.
* @param bool $updating If true, the product object won't be saved here as it will be updated later.
* @return bool|int|null
*/
function wc_update_product_stock( $product, $stock_quantity = null, $operation = 'set', $updating = false ) {
if ( ! is_a( $product, 'WC_Product' ) ) {
$product = wc_get_product( $product );
}
if ( ! $product ) {
return false;
}
if ( ! is_null( $stock_quantity ) && $product->managing_stock() ) {
// Some products (variations) can have their stock managed by their parent. Get the correct object to be updated here.
$product_id_with_stock = $product->get_stock_managed_by_id();
$product_with_stock = $product_id_with_stock !== $product->get_id() ? wc_get_product( $product_id_with_stock ) : $product;
$data_store = WC_Data_Store::load( 'product' );
// Fire actions to let 3rd parties know the stock is about to be changed.
if ( $product_with_stock->is_type( ProductType::VARIATION ) ) {
// phpcs:disable WooCommerce.Commenting.CommentHooks.MissingSinceComment
/** This action is documented in includes/data-stores/class-wc-product-data-store-cpt.php */
do_action( 'woocommerce_variation_before_set_stock', $product_with_stock );
} else {
// phpcs:disable WooCommerce.Commenting.CommentHooks.MissingSinceComment
/** This action is documented in includes/data-stores/class-wc-product-data-store-cpt.php */
do_action( 'woocommerce_product_before_set_stock', $product_with_stock );
}
// Update the database.
$new_stock = $data_store->update_product_stock( $product_id_with_stock, $stock_quantity, $operation );
// Update the product object.
$data_store->read_stock_quantity( $product_with_stock, $new_stock );
// If this is not being called during an update routine, save the product so stock status etc is in sync, and caches are cleared.
if ( ! $updating ) {
$product_with_stock->save();
}
// Fire actions to let 3rd parties know the stock changed.
if ( $product_with_stock->is_type( ProductType::VARIATION ) ) {
// phpcs:disable WooCommerce.Commenting.CommentHooks.MissingSinceComment
/** This action is documented in includes/data-stores/class-wc-product-data-store-cpt.php */
do_action( 'woocommerce_variation_set_stock', $product_with_stock );
} else {
// phpcs:disable WooCommerce.Commenting.CommentHooks.MissingSinceComment
/** This action is documented in includes/data-stores/class-wc-product-data-store-cpt.php */
do_action( 'woocommerce_product_set_stock', $product_with_stock );
}
return $product_with_stock->get_stock_quantity();
}
return $product->get_stock_quantity();
}
/**
* Update a product's stock status.
*
* @param int $product_id Product ID.
* @param string $status Status.
*/
function wc_update_product_stock_status( $product_id, $status ) {
$product = wc_get_product( $product_id );
if ( $product ) {
$product->set_stock_status( $status );
$product->save();
}
}
/**
* When a payment is complete, we can reduce stock levels for items within an order.
*
* @since 3.0.0
* @param int $order_id Order ID.
*/
function wc_maybe_reduce_stock_levels( $order_id ) {
$order = wc_get_order( $order_id );
if ( ! $order ) {
return;
}
$stock_reduced = $order->get_data_store()->get_stock_reduced( $order_id );
$trigger_reduce = apply_filters( 'woocommerce_payment_complete_reduce_order_stock', ! $stock_reduced, $order_id );
// Only continue if we're reducing stock.
if ( ! $trigger_reduce ) {
return;
}
wc_reduce_stock_levels( $order );
// Ensure stock is marked as "reduced" in case payment complete or other stock actions are called.
$order->get_data_store()->set_stock_reduced( $order_id, true );
}
add_action( 'woocommerce_payment_complete', 'wc_maybe_reduce_stock_levels' );
add_action( 'woocommerce_order_status_completed', 'wc_maybe_reduce_stock_levels' );
add_action( 'woocommerce_order_status_processing', 'wc_maybe_reduce_stock_levels' );
add_action( 'woocommerce_order_status_on-hold', 'wc_maybe_reduce_stock_levels' );
/**
* When a payment is cancelled, restore stock.
*
* @since 3.0.0
* @param int $order_id Order ID.
*/
function wc_maybe_increase_stock_levels( $order_id ) {
$order = wc_get_order( $order_id );
if ( ! $order ) {
return;
}
$stock_reduced = $order->get_data_store()->get_stock_reduced( $order_id );
$trigger_increase = (bool) $stock_reduced;
// Only continue if we're increasing stock.
if ( ! $trigger_increase ) {
return;
}
wc_increase_stock_levels( $order );
// Ensure stock is not marked as "reduced" anymore.
$order->get_data_store()->set_stock_reduced( $order_id, false );
}
add_action( 'woocommerce_order_status_cancelled', 'wc_maybe_increase_stock_levels' );
add_action( 'woocommerce_order_status_pending', 'wc_maybe_increase_stock_levels' );
/**
* Reduce stock levels for items within an order, if stock has not already been reduced for the items.
*
* @since 3.0.0
* @param int|WC_Order $order_id Order ID or order instance.
*/
function wc_reduce_stock_levels( $order_id ) {
if ( is_a( $order_id, 'WC_Order' ) ) {
$order = $order_id;
$order_id = $order->get_id();
} else {
$order = wc_get_order( $order_id );
}
// We need an order, and a store with stock management to continue.
if ( ! $order || 'yes' !== get_option( 'woocommerce_manage_stock' ) || ! apply_filters( 'woocommerce_can_reduce_order_stock', true, $order ) ) {
return;
}
$changes = array();
// Loop over all items.
foreach ( $order->get_items() as $item ) {
if ( ! $item->is_type( 'line_item' ) ) {
continue;
}
// Only reduce stock once for each item.
$product = $item->get_product();
$item_stock_reduced = $item->get_meta( '_reduced_stock', true );
if ( $item_stock_reduced || ! $product || ! $product->managing_stock() ) {
continue;
}
/**
* Filter order item quantity.
*
* @param int|float $quantity Quantity.
* @param WC_Order $order Order data.
* @param WC_Order_Item_Product $item Order item data.
*/
$qty = apply_filters( 'woocommerce_order_item_quantity', $item->get_quantity(), $order, $item );
$item_name = $product->get_formatted_name();
$new_stock = wc_update_product_stock( $product, $qty, 'decrease' );
if ( is_wp_error( $new_stock ) ) {
/* translators: %s item name. */
$order->add_order_note( sprintf( __( 'Unable to reduce stock for item %s.', 'woocommerce' ), $item_name ) );
continue;
}
$item->add_meta_data( '_reduced_stock', $qty, true );
$item->save();
$change = array(
'product' => $product,
'from' => $new_stock + $qty,
'to' => $new_stock,
);
$changes[] = $change;
/**
* Fires when stock reduced to a specific line item
*
* @param WC_Order_Item_Product $item Order item data.
* @param array $change Change Details.
* @param WC_Order $order Order data.
* @since 7.6.0
*/
do_action( 'woocommerce_reduce_order_item_stock', $item, $change, $order );
}
wc_trigger_stock_change_notifications( $order, $changes );
do_action( 'woocommerce_reduce_order_stock', $order );
}
/**
* After stock change events, triggers emails and adds order notes.
*
* @since 3.5.0
* @param WC_Order $order order object.
* @param array $changes Array of changes.
*/
function wc_trigger_stock_change_notifications( $order, $changes ) {
if ( empty( $changes ) ) {
return;
}
$order_notes = array();
$no_stock_amount = absint( get_option( 'woocommerce_notify_no_stock_amount', 0 ) );
foreach ( $changes as $change ) {
$order_notes[] = $change['product']->get_formatted_name() . ' ' . $change['from'] . '→' . $change['to'];
$low_stock_amount = absint( wc_get_low_stock_amount( wc_get_product( $change['product']->get_id() ) ) );
if ( $change['to'] <= $no_stock_amount ) {
/**
* Action to signal that the value of 'stock_quantity' for a variation is about to change.
*
* @since 4.9
*
* @param int $product The variation whose stock is about to change.
*/
do_action( 'woocommerce_no_stock', wc_get_product( $change['product']->get_id() ) );
} elseif ( $change['to'] <= $low_stock_amount ) {
/**
* Action to signal that the value of 'stock_quantity' for a product is about to change.
*
* @since 4.9
*
* @param int $product The product whose stock is about to change.
*/
do_action( 'woocommerce_low_stock', wc_get_product( $change['product']->get_id() ) );
}
if ( $change['to'] < 0 ) {
/**
* Action fires when an item in an order is backordered.
*
* @since 3.0
*
* @param array $args {
* @type WC_Product $product The product that is on backorder.
* @type int $order_id The ID of the order.
* @type int|float $quantity The amount of product on backorder.
* }
*/
do_action(
'woocommerce_product_on_backorder',
array(
'product' => wc_get_product( $change['product']->get_id() ),
'order_id' => $order->get_id(),
'quantity' => abs( $change['from'] - $change['to'] ),
)
);
}
}
$order->add_order_note( __( 'Stock levels reduced:', 'woocommerce' ) . ' ' . implode( ', ', $order_notes ) );
}
/**
* Check if a product's stock quantity has reached certain thresholds and trigger appropriate actions.
*
* This functionality was moved out of `wc_trigger_stock_change_notifications` in order to decouple it from orders,
* since stock quantity can also be updated in other ways.
*
* @param WC_Product $product The product whose stock level has changed.
*
* @return void
*/
function wc_trigger_stock_change_actions( $product ) {
if ( true !== $product->get_manage_stock() ) {
return;
}
$no_stock_amount = absint( get_option( 'woocommerce_notify_no_stock_amount', 0 ) );
$low_stock_amount = absint( wc_get_low_stock_amount( $product ) );
$stock_quantity = $product->get_stock_quantity();
if ( $stock_quantity <= $no_stock_amount ) {
/**
* Action fires when a product's stock quantity reaches the "no stock" threshold.
*
* @since 3.0
*
* @param WC_Product $product The product whose stock quantity has changed.
*/
do_action( 'woocommerce_no_stock', $product );
} elseif ( $stock_quantity <= $low_stock_amount ) {
/**
* Action fires when a product's stock quantity reaches the "low stock" threshold.
*
* @since 3.0
*
* @param WC_Product $product The product whose stock quantity has changed.
*/
do_action( 'woocommerce_low_stock', $product );
}
}
/**
* Increase stock levels for items within an order.
*
* @since 3.0.0
* @param int|WC_Order $order_id Order ID or order instance.
*/
function wc_increase_stock_levels( $order_id ) {
if ( is_a( $order_id, 'WC_Order' ) ) {
$order = $order_id;
$order_id = $order->get_id();
} else {
$order = wc_get_order( $order_id );
}
// We need an order, and a store with stock management to continue.
if ( ! $order || 'yes' !== get_option( 'woocommerce_manage_stock' ) || ! apply_filters( 'woocommerce_can_restore_order_stock', true, $order ) ) {
return;
}
$changes = array();
// Loop over all items.
foreach ( $order->get_items() as $item ) {
if ( ! $item->is_type( 'line_item' ) ) {
continue;
}
// Only increase stock once for each item.
$product = $item->get_product();
$item_stock_reduced = $item->get_meta( '_reduced_stock', true );
if ( ! $item_stock_reduced || ! $product || ! $product->managing_stock() ) {
continue;
}
$item_name = $product->get_formatted_name();
$new_stock = wc_update_product_stock( $product, $item_stock_reduced, 'increase' );
$old_stock = $new_stock - $item_stock_reduced;
if ( is_wp_error( $new_stock ) ) {
/* translators: %s item name. */
$order->add_order_note( sprintf( __( 'Unable to restore stock for item %s.', 'woocommerce' ), $item_name ) );
continue;
}
$item->delete_meta_data( '_reduced_stock' );
$item->save();
$changes[] = $item_name . ' ' . $old_stock . '→' . $new_stock;
/**
* Fires when stock restored to a specific line item
*
* @since 9.1.0
* @param WC_Order_Item_Product $item Order item data.
* @param int $new_stock New stock.
* @param int $old_stock Old stock.
* @param WC_Order $order Order data.
*/
do_action( 'woocommerce_restore_order_item_stock', $item, $new_stock, $old_stock, $order );
}
if ( $changes ) {
$order->add_order_note( __( 'Stock levels increased:', 'woocommerce' ) . ' ' . implode( ', ', $changes ) );
}
do_action( 'woocommerce_restore_order_stock', $order );
}
/**
* See how much stock is being held in pending orders.
*
* @since 3.5.0
* @param WC_Product $product Product to check.
* @param integer $exclude_order_id Order ID to exclude.
* @return int
*/
function wc_get_held_stock_quantity( WC_Product $product, $exclude_order_id = 0 ) {
/**
* Filter: woocommerce_hold_stock_for_checkout
* Allows enable/disable hold stock functionality on checkout.
*
* @since 4.3.0
* @param bool $enabled Default to true if managing stock globally.
*/
if ( ! apply_filters( 'woocommerce_hold_stock_for_checkout', wc_string_to_bool( get_option( 'woocommerce_manage_stock', 'yes' ) ) ) ) {
return 0;
}
$reserve_stock = new ReserveStock();
return $reserve_stock->get_reserved_stock( $product, $exclude_order_id );
}
/**
* Hold stock for an order.
*
* @throws ReserveStockException If reserve stock fails.
*
* @since 4.1.0
* @param \WC_Order|int $order Order ID or instance.
*/
function wc_reserve_stock_for_order( $order ) {
/**
* Filter: woocommerce_hold_stock_for_checkout
* Allows enable/disable hold stock functionality on checkout.
*
* @since @since 4.1.0
* @param bool $enabled Default to true if managing stock globally.
*/
if ( ! apply_filters( 'woocommerce_hold_stock_for_checkout', wc_string_to_bool( get_option( 'woocommerce_manage_stock', 'yes' ) ) ) ) {
return;
}
$order = $order instanceof WC_Order ? $order : wc_get_order( $order );
if ( $order ) {
$reserve_stock = new ReserveStock();
$reserve_stock->reserve_stock_for_order( $order );
}
}
add_action( 'woocommerce_checkout_order_created', 'wc_reserve_stock_for_order' );
/**
* Release held stock for an order.
*
* @since 4.3.0
* @param \WC_Order|int $order Order ID or instance.
*/
function wc_release_stock_for_order( $order ) {
/**
* Filter: woocommerce_hold_stock_for_checkout
* Allows enable/disable hold stock functionality on checkout.
*
* @since 4.3.0
* @param bool $enabled Default to true if managing stock globally.
*/
if ( ! apply_filters( 'woocommerce_hold_stock_for_checkout', wc_string_to_bool( get_option( 'woocommerce_manage_stock', 'yes' ) ) ) ) {
return;
}
$order = $order instanceof WC_Order ? $order : wc_get_order( $order );
if ( $order ) {
$reserve_stock = new ReserveStock();
$reserve_stock->release_stock_for_order( $order );
}
}
add_action( 'woocommerce_checkout_order_exception', 'wc_release_stock_for_order' );
add_action( 'woocommerce_payment_complete', 'wc_release_stock_for_order', 11 );
add_action( 'woocommerce_order_status_cancelled', 'wc_release_stock_for_order', 11 );
add_action( 'woocommerce_order_status_completed', 'wc_release_stock_for_order', 11 );
add_action( 'woocommerce_order_status_processing', 'wc_release_stock_for_order', 11 );
add_action( 'woocommerce_order_status_on-hold', 'wc_release_stock_for_order', 11 );
/**
* Release coupons used for another order.
*
* @since 9.5.2
* @param \WC_Order|int $order Order ID or instance.
* @param bool $save Save the order after releasing coupons.
*/
function wc_release_coupons_for_order( $order, bool $save = true ) {
$order = $order instanceof WC_Order ? $order : wc_get_order( $order );
if ( $order ) {
$order->get_data_store()->release_held_coupons( $order, $save );
}
}
/**
* Return low stock amount to determine if notification needs to be sent
*
* Since 5.2.0, this function no longer redirects from variation to its parent product.
* Low stock amount can now be attached to the variation itself and if it isn't, only
* then we check the parent product, and if it's not there, then we take the default
* from the store-wide setting.
*
* @param WC_Product $product Product to get data from.
* @since 3.5.0
* @return int
*/
function wc_get_low_stock_amount( WC_Product $product ) {
$low_stock_amount = $product->get_low_stock_amount();
if ( '' === $low_stock_amount && $product->is_type( ProductType::VARIATION ) ) {
$product = wc_get_product( $product->get_parent_id() );
$low_stock_amount = $product->get_low_stock_amount();
}
if ( '' === $low_stock_amount ) {
$low_stock_amount = get_option( 'woocommerce_notify_low_stock_amount', 2 );
}
return (int) $low_stock_amount;
}
But researchers now say that Viagra has another benefit — it could reduce the risk of Alzheimer’s by a fifth.
Regular users of the erectile dysfunction drug, medically known as sildenafil, were 18 per cent less likely to be diagnosed with the memory-robbing disease.
But slashing the risk of Alzheimer’s isn’t the only potential upside of taking the drug, which costs around £5 a pop.
Research has suggested it can treat heart conditions, speed up recovery from jet lag and even make treatment for some cancers more effective.
Research has suggested Viagra can treat heart conditions, speed up recovery from jet lag and even make treatment for some cancers more effective
Lowers Alzheimer’s risk
Researchers at University College London looked at 269,725 men, aged 59 on average, who had been diagnosed with erectile dysfunction but had no memory or thinking problems.
The study, published in the journal Neurology, revealed that 9.7 per 10,000 men who did not take Viagra or similar erectile dysfunction drugs developed Alzheimer’s.
But the rate was just 8.1 per 10,000 among those who did use such pills.
After adjusting for risk factors including smoking, diet and alcohol intake, the pills were linked to an 18 per cent lowered risk.
The association appeared strongest among men issued the most prescriptions — suggesting that using the drug more regularly had the most protective effect.
What happens when women take Viagra?
Women can take sildenafil for pulmonary hypertension.
This condition occurs when the vessels that supply the lungs (the pulmonary arteries) become thick and stiff, meaning they cannot expand well enough to allow blood through, which triggers high blood pressure.
Sildenafil works by relaxing the blood vessels in the chest and lowering blood pressure in the lungs, making it easier for the heart to pump blood.
However, there’s no good evidence that sildenafil works for women with sexual problems.
Viagra, one of the brand names for sildenafil, works in men by increasing blood flow to the penis.
However, research suggests Viagra is ineffective in women with sexual difficulties and that blood flow to women’s genital is not crucial for a good sexual experience.
Additionally, Viagra is only licensed for men and could trigger the same side effects in women that it does in men, which can include headaches, nausea and hot flushes.
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While the study does not conclusively prove that Viagra reduces the risk of developing Alzheimer’s, the researchers believe the results are promising.
Lead author Matthew Adesuyan said: ‘The results are encouraging and may point to a new way to reduce Alzheimer’s risk.’
It is unclear how the drug could protect against Alzheimer’s.
However, the researchers noted that Viagra affects a cell signalling messenger that is thought to be linked to memory.
If the effects are confirmed in further studies, the drug would be expected to have the same effect in women, according to the scientists.
Dr Ruth Brauer, one of the researchers, said: ‘Although we’re making progress with new treatments for Alzheimer’s disease that clear amyloid plaques in the brain, we desperately need treatments that can prevent or delay the development of Alzheimer’s disease.
‘More research is needed to confirm these findings, learn more about the potential benefits and mechanisms of these drugs and look into the optimal dosage.
‘A randomised, controlled trial with both male and female participants is warranted to determine whether these findings would apply to women as well.’
Treats pulmonary hypertension
As well as treating men with erectile dysfunction, doctors also prescribe sildenafil for pulmonary hypertension under the brand names Revatio and Grandipam.
This condition occurs when the vessels that supply the lungs (the pulmonary arteries) become thick and stiff, meaning they cannot expand well enough to allow blood through, which triggers high blood pressure.
A reduced blood flow makes it harder for the right side of the heart to pump blood through the arteries, which causes the organ to weaken over time and can lead to heart failure.
Sildenafil works by relaxing the blood vessels in the chest and lowering blood pressure in the lungs, making it easier for the heart to pump blood.
Makes it easier to urinate
As well as making it easier for men to maintain an erection, Viagra can also tackle another age-related problem — difficulty passing urine.
Around a third of men aged over 50 suffer from urinary problems and an enlarged prostate is the most common cause.
These can include difficult starting or stopping urinating, a weak flow or urine or struggling to fully empty the bladder.
Viagra works by temporarily increasing blood flow to the penis and encourages smooth muscles in the penis to relax.
Dr Irwin Goldstein, director of San Diego Sexual Medicine who has authored studies on Viagra, said this has a side effect of ‘lessening the grip of the prostate on the urethra’.
‘The higher grip is what causes difficulty in urinating,’ he told HealthLine.
Decreases jet lag
As well as being kept on people’s bedside tables, Viagra should also make its way into suitcases of jetsetters.
That’s according to a 2007 study by researchers in Argentina, who found hamsters recovered from jet lag 50 per cent faster when given Viagra.
The scientists altered the times that they turned lights on and off in a laboratory, creating the sensation that the hamsters had hopped time zones.
Some hamsters were given the drug and then monitored for how well they adapted — measured by observing when they began running on exercise wheels.
The results, published in the journal Proceedings of the National Academy of Sciences, suggested the effect was down to Viagra interfering with an enzyme that lowers levels of a compound vital for regulating the circadian cycle )the body’s internal clock).
The team suggested that the little blue pill could, therefore, help people adapt to a new time zone or shift work more easily.
Prevents mountain sickness
Viagra could help mountain climbers breathe easier and prevent them becoming unwell, 비아그라복용법 another study suggested.
Researchers at Justus-Liebig University in Germany tested 14 healthy volunteers, who had their pulmonary artery pressure and oxygen levels logged in a lab.
The same checks were repeated at the Mount Everest base camp, at around 17,000ft.
Half had been given sildenafil, while half acted as the control group.
Results, published in the journal Annals of Internal Medicine in 2004, show that the drug decreased pressure in the lungs’ blood vessels in both lab and mountain conditions.
As a result, climbers could better tolerate hypoxia — low oxygen levels, which causes altitude sickness — while scaling the Himalayan peak.
Shrinks cancerous tumours
Popping Viagra could make cancer treatment more effective, if separate research from 2022 is to be believed.
Academics at Southampton University found PDE5 inhibitors — the class of erectile dysfunction drugs that includes Viagra, Cialis and Levitra — make oesophageal tumours more vulnerable to chemotherapy.
The drugs were found to target cancer-associated fibroblasts — cells that surround tumours, support their growth and help them build up resistance to chemo.
PDE5 inhibitor drugs relax the structure of the fibroblasts so they become floppy, meaning they can no longer help the tumour to thrive and grow.
When the scientists tested PDE5 inhibitor drugs on oesophageal cancer cells in the lab and on mice, they found that chemo was effective in 75 per cent of cases.
For comparison, chemo usually only works in 20 per cent of oesophageal cancer patients.
Alzheimer’s Disease