api/services/nginx/app/tests/Unit/Invoicing/EconomicInvoiceDraftCustomerDiscountTest.php

<?php

/**
 * Tests for the e-conomic customer-level discount being applied at the line level.
 *
 * Regression coverage for bug #11 — E-conomic 15% discount not applied on
 * customer 35131752 ("kd"). The customer has a 15% global discount configured in
 * e-conomic, but the invoice was being sent without any discount on the line items.
 *
 * The fix threads the customer discount percentage through the draft builder so it
 * is applied at the line level via the `discountPercentage` field that e-conomic
 * expects on each line.
 */

app_require('modules/economic/helpers/economic_invoice_draft.php');

use helpers\economic_invoice_draft;

if (!class_exists('EconomicInvoiceDraftCustomerDiscountProbe')) {
    class EconomicInvoiceDraftCustomerDiscountProbe extends economic_invoice_draft
    {
        public array $sentBatches = [];

        public function __construct()
        {
            $this->draft_invoice_number = 35131752;
            $this->currency = 'DKK';
            $this->conversion_rate = 1.0;
            $this->draft_invoice_data = (object)['draftInvoiceNumber' => 35131752];
        }

        protected function sendDraftLines(array $draft_lines): object
        {
            $this->sentBatches[] = $draft_lines;
            return (object)['lines' => $draft_lines];
        }
    }
}

function economic_customer_discount_order_item(float $price, float $product_price, array $overrides = []): array
{
    return array_replace_recursive([
        'id' => 9001,
        'quantity' => 1,
        'price' => $price,
        'reference' => '',
        'notes' => '',
        'include_in_invoice' => true,
        'product' => [
            'economic_product_id' => '5',
            'name' => 'Wash',
            'price' => $product_price,
        ],
    ], $overrides);
}

it('applies the 15% customer discount to a line item for customer 35131752 "kd"', function (): void {
    $draft = new EconomicInvoiceDraftCustomerDiscountProbe();

    // Order item is at full price (no per-item discount) — exactly the customer 35131752
    // case where the 15% global e-conomic discount was silently dropped.
    $draft->addOrderItemLine(
        economic_customer_discount_order_item(100.0, 100.0),
        [
            'economic_department_id' => 75,
            'economic_dimension_id' => 1,
        ],
        false,
        false,
        15
    );
    $draft->flushLinesInBatches();

    $line = $draft->sentBatches[0][0];
    expect($line['product']['productNumber'])->toBe('5')
        ->and($line['description'])->toBe('Wash')
        ->and($line['quantity'])->toBe(1.0)
        ->and($line['unitNetPrice'])->toBe(100.0)
        ->and($line['discountPercentage'])->toBe(15.0);
});

it('uses the larger discount when both per-item and customer discounts are present', function (): void {
    $draft = new EconomicInvoiceDraftCustomerDiscountProbe();

    // Per-item discount = 10%, customer discount = 15% → max(15, 10) = 15.
    $draft->addOrderItemLine(
        economic_customer_discount_order_item(90.0, 100.0),
        [
            'economic_department_id' => 75,
            'economic_dimension_id' => 1,
        ],
        false,
        true,
        15
    );
    $draft->flushLinesInBatches();

    $line = $draft->sentBatches[0][0];
    expect($line['unitNetPrice'])->toBe(100.0)
        ->and($line['discountPercentage'])->toBe(15.0);
});

it('uses the per-item discount when it is larger than the customer discount', function (): void {
    $draft = new EconomicInvoiceDraftCustomerDiscountProbe();

    // Per-item discount = 25%, customer discount = 15% → max(25, 15) = 25.
    $draft->addOrderItemLine(
        economic_customer_discount_order_item(75.0, 100.0),
        [
            'economic_department_id' => 75,
            'economic_dimension_id' => 1,
        ],
        false,
        true,
        15
    );
    $draft->flushLinesInBatches();

    $line = $draft->sentBatches[0][0];
    expect($line['unitNetPrice'])->toBe(100.0)
        ->and($line['discountPercentage'])->toBe(25.0);
});

it('clamps the customer discount percentage to the 0..100 range', function (): void {
    $draft = new EconomicInvoiceDraftCustomerDiscountProbe();

    $draft->addOrderItemLine(
        economic_customer_discount_order_item(100.0, 100.0),
        [
            'economic_department_id' => 75,
            'economic_dimension_id' => 1,
        ],
        false,
        false,
        150
    );
    $draft->flushLinesInBatches();

    $line = $draft->sentBatches[0][0];
    expect($line['discountPercentage'])->toBe(100.0);
});

it('emits no line discount when both per-item and customer discounts are zero', function (): void {
    $draft = new EconomicInvoiceDraftCustomerDiscountProbe();

    $draft->addOrderItemLine(
        economic_customer_discount_order_item(100.0, 100.0),
        [
            'economic_department_id' => 75,
            'economic_dimension_id' => 1,
        ],
        false,
        false,
        0
    );
    $draft->flushLinesInBatches();

    $line = $draft->sentBatches[0][0];
    expect($line['unitNetPrice'])->toBe(100.0)
        ->and($line['discountPercentage'])->toBe(0.0);
});

it('keeps base behavior unchanged when the customer discount is zero', function (): void {
    $draft = new EconomicInvoiceDraftCustomerDiscountProbe();

    // No customer discount, no per-item discount — unit price should be the final price.
    $draft->addOrderItemLine(
        economic_customer_discount_order_item(100.0, 100.0),
        [
            'economic_department_id' => 75,
            'economic_dimension_id' => 1,
        ],
        false,
        false,
        0
    );
    $draft->flushLinesInBatches();

    $line = $draft->sentBatches[0][0];
    expect($line['unitNetPrice'])->toBe(100.0)
        ->and($line['discountPercentage'])->toBe(0.0);
});