Hooks for Discount Calculation

Filters for modifying discount calculation and price rounding.

Calculation Base Mode

Each rule can have a calculation_base_mode setting that determines which price the discount is calculated from:

Value	Constant	Description
current_price	CalculationBaseModes::CURRENT_PRICE	Discount from current price (after previous discounts) - default
original_price	CalculationBaseModes::ORIGINAL_PRICE	Discount always from regular price (regular_price)

Behavior Example — multiple Auto Price rules

Product: regular_price = $100
Rule 1 (Product): -20% → $80
Rule 2 (Bulk):    -5%

With calculation_base_mode = 'current_price' on Rule 2:
  → 5% of $80 = $4 → final $76 (stacks on Rule 1)

With calculation_base_mode = 'original_price' on Rule 2:
  → 5% of $100 = $5 → final $95 (overrides Rule 1, recalculated from regular_price)

When multiple Auto Price rules match the same product, they are applied in priority order (lower menu_order first). Each rule’s calculation_base_mode decides whether it stacks on the running price or restarts from regular_price. The stop_processing flag halts iteration over lower-priority rules.

Behavior Example — Auto Price + BOGO

Product: regular_price = $100
Rule 1 (Product): -20% → price = $80
Rule 2 (BOGO): -50%

With calculation_base_mode = 'current_price':
  → 50% of 80 = $40 (discounts stack)

With calculation_base_mode = 'original_price':
  → 50% of 100 = $50 (discount from original price)

Accessing the Setting in Code

use WpifyWooDiscountRule\Services\Rules;
use WpifyWooDiscountRule\Enums\CalculationBaseModes;

// Within a rule
$calc_base_mode = $rule[ Rules::CALCULATION_BASE_MODE ] ?? CalculationBaseModes::CURRENT_PRICE;

if ( CalculationBaseModes::ORIGINAL_PRICE === $calc_base_mode ) {
    // Use regular_price
    $base = $product->get_regular_price();
} else {
    // Use current price (may include other discounts)
    $base = $product->get_price();
}

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Modifying Data Before Discount Calculation

This filter allows you to modify data before the actual discount calculation.

apply_filters( 'wpify_woo_discounts_calculate_data', $data, $product, $rule, $range );

Filter Parameters

Parameter	Type	Description
$data	array	Data for discount calculation (original_price, calculation_base, discount_type, discount_value)
$product	WC_Product	Product the discount is applied to
$rule	array	Rule settings (including calculation_base_mode)
$range	array	Current discount range/tier

Usage Examples

Adjusting Discount for a Specific Category

/**
 * Increase discount for products in the "sale" category
 *
 * @param array      $data    Calculation data
 * @param WC_Product $product Product
 * @param array      $rule    Rule
 * @param array      $range   Discount range
 *
 * @return array
 */
function boost_discount_for_sale_category( $data, $product, $rule, $range ): array {
    if ( has_term( 'akce', 'product_cat', $product->get_id() ) ) {
        // Increase percentage discount by 5%
        if ( $data['discount_type'] === 'percentage' && isset( $data['discount_value'] ) ) {
            $data['discount_value'] += 5;
        }
    }
    return $data;
}
add_filter( 'wpify_woo_discounts_calculate_data', 'boost_discount_for_sale_category', 10, 4 );

Setting a Minimum Discount

/**
 * Ensure a minimum discount of 10%
 *
 * @param array      $data    Calculation data
 * @param WC_Product $product Product
 * @param array      $rule    Rule
 * @param array      $range   Discount range
 *
 * @return array
 */
function ensure_minimum_discount( $data, $product, $rule, $range ): array {
    if ( $data['discount_type'] === 'percentage' ) {
        $data['discount_value'] = max( 10, $data['discount_value'] ?? 0 );
    }
    return $data;
}
add_filter( 'wpify_woo_discounts_calculate_data', 'ensure_minimum_discount', 10, 4 );

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Modifying the Discount Calculation Result

This filter allows you to modify the result after the discount has been calculated.

apply_filters( 'wpify_woo_discounts_calculate_product_discount', $result, $product, $rule, $range );

Filter Parameters

Parameter	Type	Description
$result	array	Calculation result (discounted_price, discount_amount, discount_percentage)
$product	WC_Product	Product
$rule	array	Rule settings
$range	array	Discount range

Usage Examples

Logging Discount Calculations

/**
 * Log all discount calculations
 *
 * @param array      $result  Calculation result
 * @param WC_Product $product Product
 * @param array      $rule    Rule
 * @param array      $range   Discount range
 *
 * @return array
 */
function log_discount_calculation( $result, $product, $rule, $range ): array {
    if ( defined( 'WP_DEBUG' ) && WP_DEBUG ) {
        error_log( sprintf(
            'Discount calculated: Product #%d, Original: %s, Discounted: %s',
            $product->get_id(),
            $result['original_price'] ?? 'N/A',
            $result['discounted_price'] ?? 'N/A'
        ) );
    }
    return $result;
}
add_filter( 'wpify_woo_discounts_calculate_product_discount', 'log_discount_calculation', 10, 4 );

---

Modifying Price Rounding

This filter allows you to modify the rounding logic of the final discounted price.

apply_filters( 'wpify_woo_discounts_round_price', $rounded_price, $original_price, $rounding_mode, $rule );

Filter Parameters

Parameter	Type	Description
$rounded_price	float	Price after rounding (according to the configured mode)
$original_price	float	Price before rounding (after discount)
$rounding_mode	string	Mode: whole, ending_99, ending_90, ending_9
$rule	array	Complete rule data

Usage Examples

Custom Rounding for VIP Customers

/**
 * Always round down for VIP customers
 *
 * @param float  $rounded_price  Rounded price
 * @param float  $original_price Price before rounding
 * @param string $rounding_mode  Rounding mode
 * @param array  $rule           Rule
 *
 * @return float
 */
function vip_rounding( $rounded_price, $original_price, $rounding_mode, $rule ): float {
    if ( current_user_can( 'vip_member' ) ) {
        return floor( $original_price );
    }
    return $rounded_price;
}
add_filter( 'wpify_woo_discounts_round_price', 'vip_rounding', 10, 4 );

Rounding to Multiples of 10

/**
 * Round price to multiples of 10
 *
 * @param float  $rounded_price  Rounded price
 * @param float  $original_price Price before rounding
 * @param string $rounding_mode  Rounding mode
 * @param array  $rule           Rule
 *
 * @return float
 */
function round_to_tens( $rounded_price, $original_price, $rounding_mode, $rule ): float {
    return round( $original_price / 10 ) * 10;
}
add_filter( 'wpify_woo_discounts_round_price', 'round_to_tens', 10, 4 );

---

Controlling Discount Application (Subscriptions)

Filter to control whether a discount should be applied. Primarily used for WooCommerce Subscriptions.

apply_filters( 'wpify_woo_discounts_should_apply_discount', $should_apply, $rule );

Filter Parameters

Parameter	Type	Description
$should_apply	bool	Default value (true)
$rule	array	Rule data including renewal_behavior

Usage Examples

Disabling Bulk Discounts on Renewals

/**
 * Never apply bulk discounts on renewal orders
 *
 * @param bool  $should_apply Default value
 * @param array $rule         Rule
 *
 * @return bool
 */
function no_bulk_on_renewals( $should_apply, $rule ): bool {
    if ( function_exists( 'wcs_cart_contains_renewal' ) && wcs_cart_contains_renewal() ) {
        if ( ( $rule['rule_type'] ?? '' ) === 'bulk' ) {
            return false;
        }
    }
    return $should_apply;
}
add_filter( 'wpify_woo_discounts_should_apply_discount', 'no_bulk_on_renewals', 10, 2 );

Available renewal behavior values:

• first_order_only - Discount only on the first order
• renewals_only - Discount only on renewal orders
• both - Discount on both (default)

---

Modifying Target Products

This filter allows you to modify the list of target products after they have been prepared.

apply_filters( 'wpify_woo_discounts_targets_prepared', $targets, $rule );

Filter Parameters

Parameter	Type	Description
$targets	array	Array of target products
$rule	array	Rule settings

Usage Example

/**
 * Exclude low-margin products from discount targets
 *
 * @param array $targets Target products
 * @param array $rule    Rule
 *
 * @return array
 */
function exclude_low_margin_products( $targets, $rule ): array {
    return array_filter( $targets, function( $target ) {
        $product_id = $target['product_id'] ?? 0;
        $margin = get_post_meta( $product_id, '_profit_margin', true );
        return $margin > 10; // Exclude products with margin below 10%
    } );
}
add_filter( 'wpify_woo_discounts_targets_prepared', 'exclude_low_margin_products', 10, 2 );

---

Modifying Subrule Metadata

This filter allows you to add custom metadata to subrules (discount tiers).

apply_filters( 'wpify_woo_discounts_subrule_metadata', $metadata, $subrule, $rule );

Filter Parameters

Parameter	Type	Description
$metadata	array	Subrule metadata
$subrule	array	Subrule data
$rule	array	Rule settings

Usage Example

/**
 * Add custom metadata for tracking
 *
 * @param array $metadata Metadata
 * @param array $subrule  Subrule
 * @param array $rule     Rule
 *
 * @return array
 */
function add_tracking_metadata( $metadata, $subrule, $rule ): array {
    $metadata['campaign_id'] = $rule['campaign_id'] ?? '';
    $metadata['applied_at'] = current_time( 'mysql' );
    return $metadata;
}
add_filter( 'wpify_woo_discounts_subrule_metadata', 'add_tracking_metadata', 10, 3 );

---

Modifying the Quantity Limit

This filter allows you to modify the maximum quantity for a discount.

apply_filters( 'wpify_woo_discounts_quantity_limit', $limit, $product, $rule );

Filter Parameters

Parameter	Type	Description
$limit	int	Quantity limit
$product	WC_Product	Product
$rule	array	Rule settings

Usage Example

/**
 * Limit quantity for wholesale customers
 *
 * @param int        $limit   Limit
 * @param WC_Product $product Product
 * @param array      $rule    Rule
 *
 * @return int
 */
function limit_wholesale_quantity( $limit, $product, $rule ): int {
    if ( current_user_can( 'wholesale_customer' ) ) {
        return min( $limit, 100 ); // Max 100 pcs for wholesale
    }
    return $limit;
}
add_filter( 'wpify_woo_discounts_quantity_limit', 'limit_wholesale_quantity', 10, 3 );

---

Fee Application Type

This filter allows you to modify the fee/discount application type in the cart.

apply_filters( 'wpify_woo_discounts_fee_application_type', $type, $rule );

Filter Parameters

Parameter	Type	Description
$type	string	Application type (fixed, percent)
$rule	array	Rule settings

Usage Example

/**
 * Change application type for specific rules
 *
 * @param string $type Application type
 * @param array  $rule Rule
 *
 * @return string
 */
function change_fee_application_type( $type, $rule ): string {
    // Use percentage for rules with the high_value tag
    if ( in_array( 'high_value', $rule['tags'] ?? [], true ) ) {
        return 'percent';
    }
    return $type;
}
add_filter( 'wpify_woo_discounts_fee_application_type', 'change_fee_application_type', 10, 2 );

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Bundle Set Price

This filter returns the price of a concrete bundle product selection — useful for custom selectors, blocks or templates that need to display the bundle price before the products are added to the cart. The filter matches the provided products against active Bundle rules and returns the discounted total of the first matching variant.

apply_filters( 'wpify_woo_discounts_bundle_set_price', $result, $products, $context );

Filter Parameters

Parameter	Type	Description
$result	array|null	Previously computed payload (pass null as the initial value)
$products	WC_Product[]	One product per Bundle slot; slot quantities are read from the rule
$context	array	Optional. 'application_mode' => string|string[] limits matching to rules containing that mode (default: no filtering)

Return Value

null when no Bundle variant matches the supplied products; otherwise an array with:

Key	Type	Description
rule_id	string	Matching rule identifier
variant_id	string	Matching variant (filter group) identifier
regular_total	float	Sum of unit_price × slot_qty across all slots
discounted_total	float	Sum of discounted_unit_price × slot_qty across all slots
slots	array	Per-slot breakdown: slot_id, product_id, product, slot_qty, unit_price, discounted_unit_price
html	string	Pre-rendered strikethrough HTML (wc_format_sale_price when discounted, wc_price otherwise)

Usage Example

/**
 * Render bundle price in a custom selector template.
 *
 * @param WC_Product[] $selected_products Products the customer picked.
 */
function render_bundle_set_price( array $selected_products ): void {
    $price = apply_filters(
        'wpify_woo_discounts_bundle_set_price',
        null,
        $selected_products
    );

    if ( null === $price ) {
        return; // no bundle matched
    }

    echo $price['html']; // or build your own markup from $price['regular_total'] / $price['discounted_total']
}

To limit matching to a specific application mode (e.g. only Auto Price bundles):

$price = apply_filters(
    'wpify_woo_discounts_bundle_set_price',
    null,
    $selected_products,
    [ 'application_mode' => 'auto_price' ]
);

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Where to Place the Code

You can add custom functions either in your child theme’s functions.php or using the Code Snippets plugin.