Custom calculations for Quote totals

Note: The same mechanism is also available for Sales Orders and Invoices.

Problem

You have added custom fields to quote items or/and quote entity types. You want Total Amount field and other totals to be calculated considering new custom fields.

Resolution

Server-side calculation

You need to create a custom Hook for the Quote entity type.

Create a new file:

custom/Espo/Custom/Hooks/Quote/CalculateItems.php

```php <?php namespace Espo\Custom\Hooks\Quote;

use Espo\ORM\Entity;

class CalculateItems {         public static int $order = 10;

public function __construct(         // Define needed dependencies.     ) {}

public function beforeSave(Entity $entity, array $options): void     {         if (!$entity->has('itemList')) {              $entity->loadItemListField();         }

    $itemList = $entity->get('itemList');

    $amount = 0.0;
    foreach ($itemList as $item) {
        $amount +=  $item->quantity * $item->unitPrice * $item->factor;
    }
    $entity->set('amount', $amount);

} }​ ```

Note: For other entity types, e.g. SalesOrder, do the same but use SalesOrder namespace and file location instead of Quote.

Client-side calculation

In Quote's clientDefs you need to specify custom calculation handler:

File: custom/Espo/Custom/Resources/metadata/clientDefs/Quote.json

json { "calculationHandler": "custom:quote-calculation-handler" }

Note: For Sales Orders use SalesOrder.json file names. For Invoices use Invoice.json file names.

Create a new file:

client/custom/src/quote-calculation-handler.js

```js define(['sales:quote-calculation-handler'], (Dep) => {

return class extends Dep {

    // Define custom calculations here.
    // Use client/modules/sales/quote-calculation-handler.js as an example.

    /**
     * Calculate.
     *
     * @param {import('model').default} model An order.
     */
    calculate(model) {
        super.calculate(model);
    }

    /**
     * Calculate item.
     *
     * @param {import('model').default} model An item.
     * @param {string} [field] A field that was changed.
     */
    calculateItem(model, field) {
        super.calculateItem(model, field);
    }

    /**
     * Select product.
     *
     * @param {import('model').default} model
     * @param {import('model').default} product
     */
    selectProduct(model, product) {
        super.selectProduct(model, product);
    }

    /**
     * Get select product attributes.
     *
     * @param {import('model').default} model
     * @return {string[]}
     */
    getSelectProductAttributeList(model) {
        super.getSelectProductAttributeList(model);
    }
}

}); ```

It's also possible to make certain product fields copied to a quote item on product selection. The logic is determined in selectProduct method.