Multiprices - Multiprices for OpenCart/OcStore

What's the purpose of this module?
The standard OpenCart system only has one product price. If you need to display different prices to different customers—retail, wholesale, dealers, VIP clients—you have to install multiple modules or use workarounds.

Multiprices solves this problem systematically: you create custom price fields, assign them to customer groups, fill in the prices on the product page, and the module automatically displays the correct price to each customer everywhere on the site.

Key features:
Unlimited number of price fields — Retail, Wholesale, Purchase, Dealer, and any other
Link to customer groups — each field can be linked to one or more groups with customizable priorities
Price substitution everywhere — catalog listing, product card, cart, checkout
Promotional prices by field — similar to standard OC promotions, but for each field separately, linked to a group and validity period
Bulk price editing — update prices for the entire catalog or category in one operation (fixed, ±amount, ±%, ×÷)
Bulk promotion creation — launch a sale for the entire catalog or category in seconds
Incomplete price audit — a service tab displays products where the price field is empty, with the ability to edit directly in the table
Price summary in product listings — an additional column in the admin panel product list shows the completed prices and the number of active promotions for each product
Safe fallback — if there is no price for a product in a field or module Disabled, the standard OC price is shown. The product is never hidden.

How it works:
When opening a product page, the module determines the current customer's group and searches for an active price field for it. If the field is found and a price is entered for the product, it overrides the standard OC price. If there is an active promotion for the field (taking into account dates and the group), the promotional price is applied. If the field is empty, the module silently reverts to the standard OC price.

Example:
"Retail" group → "Retail price" field → 199 UAH is displayed
"Wholesale" group → "Wholesale price" field → 150 UAH is displayed
"Dealer" group → "Dealer price" field, active promotion → 120 UAH is displayed (instead of the standard 130 UAH)
Unlogged-in user → standard OS price

Administrator interface:
Price fields
Manage price fields: create, edit, delete, sort. For each field, the following can be configured:
- Name (multilingual)
- Link to customer groups with individual priorities
- Status (enabled/disabled)
When deleting a field for which product prices are already filled in, the system warns about the number of affected products and requires confirmation.

Bulk Price Editing
Batch price updates for the entire catalog or a selected category (with the option to include nested subcategories). Supported operations:
- Set a fixed price
- Add/subtract an amount
- Add/subtract a percentage
- Multiply/divide by a coefficient
Operation source and target — independently selectable from the standard catalog price or any module field. For example: "take the wholesale price, subtract 10%, and enter it in the dealer price."

Bulk Promotion Creation
Quickly create promotional prices for a group of products. Settings:
- Object: entire catalog / category / category + nested
- Price type: standard catalog or module field
- Customer group
- Promotional price calculation operation (fixed / ±amount / ±%)
- Priority and validity period (start / end date)

Service (Price Audit)
Shows products for which the price for the selected field is missing. Filter by field and category, pagination, and inline price editing directly in the table row without going to the product page.

Integration with the product page
Two new tabs have been added to the standard product editing form:
Module Prices - a table of all active price fields with an input field for each. Saved by clicking "Save."
Module Promotions - similar to the standard "Promotions" tab in OC, but linked to module fields. Each row contains: price field, customer group, priority, promotional price, start and end dates.

What the module doesn't change:
- Standard OC prices (the 'price' field in the 'product' table) are unaffected.
- Standard OC promotions run in parallel; the module doesn't delete them.
- Website template: the module doesn't interfere with frontend templates.
- If the module is disabled or if a license is missing, the website functions completely as usual.

License:
Commercial module with domain binding.
The license is verified through a secure server.
One license per domain.

This module works correctly in conjunction with Loyalty Levels — multi-level loyalty program for OpenCart/OcStore