<?php

namespace Tests\App\Libraries;

use App\Libraries\RefundEligibilityService;
use CodeIgniter\Test\CIUnitTestCase;

class RefundEligibilityServiceHarness extends RefundEligibilityService
{
    public function __construct(
        private int $sourceCreditCents,
        private int $completedPayoutCents,
        private int $reservedAmountCents
    ) {
    }

    protected function calculateSourceCreditCents(int $parentId, ?int $invoiceId, string $sourceType, int $sourceId): int
    {
        return $this->sourceCreditCents;
    }

    protected function calculateCompletedPayoutCents(string $sourceType, int $sourceId, ?int $excludeRefundId): int
    {
        return $this->completedPayoutCents;
    }

    protected function calculateReservedAmountCents(string $sourceType, int $sourceId, ?int $excludeRefundId): int
    {
        return $this->reservedAmountCents;
    }
}

class RefundEligibilityServiceTest extends CIUnitTestCase
{
    public function testInvoiceOverpaymentAvailableCreditDoesNotDoubleSubtractCompletedPayouts(): void
    {
        $service = new RefundEligibilityServiceHarness(10000, 2500, 1500);

        $result = $service->calculateAvailableCredit(10, 20, 'invoice_overpayment', 20);

        $this->assertSame(10000, $result->sourceCreditCents);
        $this->assertSame(0, $result->completedPayoutCents);
        $this->assertSame(1500, $result->reservedAmountCents);
        $this->assertSame(8500, $result->availableAmountCents);
        $this->assertNotContains('HAS_COMPLETED_PAYOUTS', $result->reasonCodes);
        $this->assertContains('HAS_APPROVED_RESERVATIONS', $result->reasonCodes);
    }

    public function testPaymentSourceAvailableCreditSubtractsCompletedPayoutsAndReservations(): void
    {
        $service = new RefundEligibilityServiceHarness(10000, 2500, 1500);

        $result = $service->calculateAvailableCredit(10, 20, 'payment_duplicate', 77);

        $this->assertSame(10000, $result->sourceCreditCents);
        $this->assertSame(2500, $result->completedPayoutCents);
        $this->assertSame(1500, $result->reservedAmountCents);
        $this->assertSame(6000, $result->availableAmountCents);
        $this->assertContains('HAS_COMPLETED_PAYOUTS', $result->reasonCodes);
        $this->assertContains('HAS_APPROVED_RESERVATIONS', $result->reasonCodes);
    }

    public function testValidateRejectsAmountAboveAvailableCredit(): void
    {
        $service = new RefundEligibilityServiceHarness(10000, 7000, 1000);
        $result = $service->calculateAvailableCredit(10, 20, 'payment_duplicate', 20);

        $this->expectException(\RuntimeException::class);
        $this->expectExceptionMessage('Refund amount exceeds available source credit.');

        $service->validateRequestedAmount($result, 2500);
    }

    public function testValidateRejectsNonPositiveAmount(): void
    {
        $service = new RefundEligibilityServiceHarness(10000, 0, 0);
        $result = $service->calculateAvailableCredit(10, 20, 'invoice_overpayment', 20);

        $this->expectException(\RuntimeException::class);
        $this->expectExceptionMessage('Refund amount must be greater than zero.');

        $service->validateRequestedAmount($result, 0);
    }

    public function testZeroAvailableCreditCarriesReasonCodes(): void
    {
        $service = new RefundEligibilityServiceHarness(0, 0, 0);

        $result = $service->calculateAvailableCredit(10, 20, 'invoice_overpayment', 20);

        $this->assertSame(0, $result->availableAmountCents);
        $this->assertContains('NO_SOURCE_CREDIT', $result->reasonCodes);
        $this->assertContains('NO_AVAILABLE_CREDIT', $result->reasonCodes);
    }
}