<?php

namespace App\Libraries;

use App\Models\InvoiceModel;

class ParentLedgerService
{
    protected InvoiceModel $invoiceModel;
    protected InvoiceLedgerService $invoiceLedgerService;
    protected RefundEligibilityService $refundEligibilityService;

    public function __construct()
    {
        $this->invoiceModel = new InvoiceModel();
        $this->invoiceLedgerService = new InvoiceLedgerService();
        $this->refundEligibilityService = new RefundEligibilityService();
    }

    public function getParentProjection(int $parentId, string $schoolYear, ?string $semester = null): array
    {
        $invoices = $this->loadInvoices($parentId, $schoolYear, $semester);

        $grossChargesCents = 0;
        $discountCents = 0;
        $netInvoiceChargesCents = 0;
        $validPaymentCents = 0;
        $completedRefundCents = 0;
        $balanceDueCents = 0;
        $customerCreditCents = 0;
        $approvedRefundReservationCents = 0;
        $availableRefundableCreditCents = 0;
        $invoiceProjections = [];

        foreach ($invoices as $invoice) {
            $invoiceId = (int)($invoice['id'] ?? 0);
            if ($invoiceId <= 0) {
                continue;
            }

            $ledger = $this->ledgerForInvoice($invoiceId);
            $eligibility = $this->eligibilityForSource(
                $parentId,
                $invoiceId,
                'invoice_overpayment',
                $invoiceId
            );

            $invoiceGrossCents = (int)($ledger['totalAmountCents'] ?? 0);
            $invoiceDiscountCents = (int)($ledger['discountCents'] ?? 0);
            $grossChargesCents += $invoiceGrossCents;
            $discountCents += $invoiceDiscountCents;
            $netInvoiceChargesCents += max(0, $invoiceGrossCents - $invoiceDiscountCents);
            $validPaymentCents += (int)($ledger['paidCents'] ?? 0);
            $completedRefundCents += (int)($ledger['completedRefundCents'] ?? 0);
            $balanceDueCents += (int)($ledger['balanceDueCents'] ?? 0);
            $customerCreditCents += (int)($ledger['customerCreditCents'] ?? 0);
            $approvedRefundReservationCents += $eligibility->reservedAmountCents;
            $availableRefundableCreditCents += $eligibility->availableAmountCents;

            $invoiceProjections[] = [
                'invoice_id' => $invoiceId,
                'invoice_number' => (string)($invoice['invoice_number'] ?? ''),
                'grossChargesCents' => $invoiceGrossCents,
                'discountCents' => $invoiceDiscountCents,
                'netInvoiceChargesCents' => max(0, $invoiceGrossCents - $invoiceDiscountCents),
                'validPaymentCents' => (int)($ledger['paidCents'] ?? 0),
                'completedRefundCents' => (int)($ledger['completedRefundCents'] ?? 0),
                'balanceDueCents' => (int)($ledger['balanceDueCents'] ?? 0),
                'customerCreditCents' => (int)($ledger['customerCreditCents'] ?? 0),
                'approvedRefundReservationCents' => $eligibility->reservedAmountCents,
                'availableRefundableCreditCents' => $eligibility->availableAmountCents,
                'status' => (string)($ledger['status'] ?? ''),
            ];
        }

        return [
            'parent_id' => $parentId,
            'school_year' => $schoolYear,
            'semester' => $semester,
            'grossChargesCents' => $grossChargesCents,
            'discountCents' => $discountCents,
            'netInvoiceChargesCents' => $netInvoiceChargesCents,
            'validPaymentCents' => $validPaymentCents,
            'completedRefundCents' => $completedRefundCents,
            'balanceDueCents' => $balanceDueCents,
            'customerCreditCents' => $customerCreditCents,
            'approvedRefundReservationCents' => $approvedRefundReservationCents,
            'availableRefundableCreditCents' => $availableRefundableCreditCents,
            'gross_charges' => $this->fromCents($grossChargesCents),
            'discounts' => $this->fromCents($discountCents),
            'net_invoice_charges' => $this->fromCents($netInvoiceChargesCents),
            'valid_payments' => $this->fromCents($validPaymentCents),
            'completed_refunds' => $this->fromCents($completedRefundCents),
            'balance_due' => $this->fromCents($balanceDueCents),
            'customer_credit' => $this->fromCents($customerCreditCents),
            'approved_refund_reservations' => $this->fromCents($approvedRefundReservationCents),
            'available_refundable_credit' => $this->fromCents($availableRefundableCreditCents),
            'invoices' => $invoiceProjections,
        ];
    }

    protected function loadInvoices(int $parentId, string $schoolYear, ?string $semester): array
    {
        $query = $this->invoiceModel
            ->where('parent_id', $parentId)
            ->where('school_year', $schoolYear);

        if ($semester !== null && $semester !== '') {
            $query->where('semester', $semester);
        }

        return $query->orderBy('id', 'ASC')->findAll();
    }

    protected function ledgerForInvoice(int $invoiceId): array
    {
        return $this->invoiceLedgerService->calculateInvoice($invoiceId);
    }

    protected function eligibilityForSource(
        int $parentId,
        ?int $invoiceId,
        string $sourceType,
        int $sourceId
    ): RefundEligibilityResult {
        return $this->refundEligibilityService->calculateAvailableCredit(
            $parentId,
            $invoiceId,
            $sourceType,
            $sourceId
        );
    }

    private function fromCents(int $cents): string
    {
        return number_format($cents / 100, 2, '.', '');
    }
}