<?php

namespace Tests\App\Libraries;

use App\Libraries\FinancialStatus;
use App\Libraries\InvoiceLedgerService;
use CodeIgniter\Test\CIUnitTestCase;

class InvoiceLedgerServiceHarness extends InvoiceLedgerService
{
    private array $invoice;
    private float $paidTotal;

    public function __construct(array $invoice, float $paidTotal = 0.0)
    {
        $this->invoice = $invoice;
        $this->paidTotal = $paidTotal;
    }

    protected function loadInvoice(int $invoiceId): ?array
    {
        return $invoiceId === (int) ($this->invoice['id'] ?? 0) ? $this->invoice : null;
    }

    protected function calculateTuitionTotal(array $invoice): float
    {
        return 0.0;
    }

    protected function calculateEventTotal(array $invoice): float
    {
        return 0.0;
    }

    protected function calculateAdditionalCharges(int $invoiceId): float
    {
        return 0.0;
    }

    protected function calculateDiscounts(int $invoiceId): float
    {
        return 0.0;
    }

    protected function calculateValidPayments(int $invoiceId): float
    {
        return $this->paidTotal;
    }

    protected function calculatePaidRefunds(int $invoiceId): float
    {
        return 0.0;
    }
}

class InvoiceLedgerServiceTest extends CIUnitTestCase
{
    public function testCarryForwardInvoiceUsesStoredOpeningBalance(): void
    {
        $service = new InvoiceLedgerServiceHarness([
            'id' => 10,
            'invoice_number' => 'CF-20252026-20262027-P8-I4',
            'total_amount' => '90.00',
            'semester' => 'Opening Balance',
            'description' => 'Balance carried over from previous school year 2025-2026.',
        ]);

        $calculation = $service->calculateInvoice(10);

        $this->assertSame('90.00', $calculation['total_amount']);
        $this->assertSame('90.00', $calculation['balance']);
        $this->assertSame(FinancialStatus::INVOICE_UNPAID, $calculation['status']);
    }

    public function testCarryForwardInvoiceIsPaidAfterFullPayment(): void
    {
        $service = new InvoiceLedgerServiceHarness([
            'id' => 10,
            'invoice_number' => 'CF-20252026-20262027-P8-I4',
            'total_amount' => '90.00',
            'semester' => 'Opening Balance',
            'description' => 'Balance carried over from previous school year 2025-2026.',
        ], 90.0);

        $calculation = $service->calculateInvoice(10);

        $this->assertSame('90.00', $calculation['total_amount']);
        $this->assertSame('0.00', $calculation['balance']);
        $this->assertSame(FinancialStatus::INVOICE_PAID, $calculation['status']);
    }
}