When a customer reaches the payment step, the module watches which gateway they select. For each installed payment module you can define a pricing rule: either a discount (cart total goes down) or a surcharge (cart total goes up). The adjustment appears in the order summary, optional badges next to payment names, and on the final order record.

Typical uses: -2% for bank transfer, +3% for card, fixed COD fee, B2B group exceptions, country-specific incentives. You are pricing the payment choice, not editing product prices manually.

The Pricing rules tab is a full rule manager with preview grid and add/edit form. Each rule targets one payment module and defines:

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  Adjustment type - discount or surcharge
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  Value - percent or fixed amount, with cart min/max and max adjustment cap
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  Scope - currencies, countries, zones, customer groups via visual selectors
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  Exclusions - products, categories, manufacturers, suppliers (searchTool autocomplete)
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  Multilingual checkout label shown next to totals and on payment badges

Discounts are applied as native PrestaShop cart rules created on the fly. Each cart gets an unpredictable PDF-* code stored in module state. Rules are bound to the logged-in customer when applicable, protected against manual reuse, and deleted when the customer switches payment method or completes the order.

The audit log records every cart rule creation and deletion with actor, cart ID and cleanup reason (payment change, cron, post-order sync). Your Catalog > Cart rules list stays clean.

Surcharges use a dedicated hidden fee product configured in Settings. During checkout the amount is stored in module cart state and shown as a subtotal line without mutating cart composition. When the customer places the order, the fee product is materialized with the correct tax rule and amount.

Price calculation hooks lock the fee line to the computed surcharge so PrestaShop totals stay consistent. Surcharge apply and remove events are written to the audit log with customer or system actor.

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  Global switches

  Enable module, live total updates, payment badges and optional legal disclaimer on the payment step.
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  Surcharge fee product picker

  Standard HelperForm field to select or auto-create the hidden fee product used for surcharges.
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  Theme-friendly checkout JS

  Works with classic and modern checkout themes. Configurable CSS selectors for cart total patching when needed.

The Dashboard tab shows KPI cards for surcharges, discounts and net impact over a selectable period. Chart.js graphs cover weekly, monthly and yearly trends. Tables break down totals by month and top payment modules. Export order-level data to CSV for accounting.

The Audit log tab (dedicated admin controller) is read-only and colour-coded: orders, rule CRUD, settings changes, cart rule lifecycle, surcharge events. Actor pills identify customer, employee, system or cron. Every pricing decision leaves a trace.

The Cron cleanup tab explains why orphan cart rules appear, gives you a secret URL with regenerate button, and documents setup for cPanel, DirectAdmin, Plesk, SSH and external cron services. Maintenance purges stale PDF-* rules and idle cart states automatically.

On each order the module stores paydisorfee_amount, type and rule ID on the order row, validates that the placed payment matches the applied adjustment, logs the event, then clears cart state. A hook on the admin order page shows the adjustment summary for support staff.