<?php

namespace App\Services\Billing;

use App\Models\LegacyInvoice;
use Illuminate\Support\Carbon;
use Illuminate\Support\Str;
use Symfony\Component\HttpFoundation\Response;

class LegacyInvoicePdfRenderer
{
    private const PAGE_WIDTH = 595;

    private const PAGE_HEIGHT = 842;

    private const LEFT = 91;

    private const RIGHT = 524;

    public function inlineResponse(LegacyInvoice $invoice): Response
    {
        $pdf = $this->render($invoice);

        return response($pdf, Response::HTTP_OK, [
            'Content-Type' => 'application/pdf',
            'Content-Disposition' => 'inline; filename="'.$this->filename($invoice).'"',
            'Cache-Control' => 'private, max-age=0, must-revalidate',
        ]);
    }

    public function downloadResponse(LegacyInvoice $invoice): Response
    {
        $pdf = $this->render($invoice);

        return response()->streamDownload(
            static function () use ($pdf): void {
                echo $pdf;
            },
            $this->filename($invoice),
            [
                'Content-Type' => 'application/pdf',
                'Cache-Control' => 'private, max-age=0, must-revalidate',
            ],
        );
    }

    public function render(LegacyInvoice $invoice): string
    {
        $data = $this->data($invoice);
        $content = '';
        $isMedia = $data['is_media'];

        $this->drawHeader($content, $isMedia);
        $this->drawInvoiceBody($content, $data);
        $this->drawFooter($content, $isMedia);

        return $this->buildPdf($content);
    }

    public function filename(LegacyInvoice $invoice): string
    {
        $number = filled($invoice->number) ? (string) $invoice->number : (string) $invoice->legacy_id;
        $number = preg_replace('/[^A-Za-z0-9._-]/', '-', Str::ascii($number)) ?: (string) $invoice->id;

        $portal = preg_replace('/[^A-Za-z0-9._-]/', '-', Str::ascii($invoice->legacy_portal->label()));

        return "{$portal}-RNr-{$number}.pdf";
    }

    /**
     * @return array{
     *     invoice: LegacyInvoice,
     *     billing_address: array<string, mixed>,
     *     invoice_data: array<string, mixed>,
     *     is_media: bool,
     *     is_netto: bool,
     *     tax_percent: int,
     *     amount: float,
     *     net_amount: float,
     *     tax_amount: float,
     *     service_name: string,
     *     service_period_begin: string,
     *     service_period_end: string
     * }
     */
    private function data(LegacyInvoice $invoice): array
    {
        $payload = $invoice->pdf_payload ?? [];
        $billingAddress = data_get($payload, 'billing_address') ?: [];
        $invoiceData = data_get($payload, 'invoice', $invoice->raw_snapshot ?? []);
        $invoice->loadMissing('user.profile');

        $isNetto = (bool) data_get($invoiceData, 'is_netto', false);
        $isMedia = (bool) data_get($invoiceData, 'is_media', true);
        $taxPercent = $this->taxPercent($invoice);
        $amount = $invoice->total_cents / 100;
        $netAmount = $isNetto ? $amount : $amount / (1 + ($taxPercent / 100));
        $taxAmount = $isNetto ? 0 : $amount - $netAmount;
        $servicePeriodBegin = $this->formatLegacyDate(data_get($invoiceData, 'service_period_begin_date'));
        $servicePeriodEnd = $this->formatLegacyDate(data_get($invoiceData, 'service_period_end_date'));
        $serviceName = data_get($payload, 'payment_option_translation.name')
            ?? data_get($payload, 'payment_option.article_number')
            ?? 'Legacy-Leistung';

        return [
            'invoice' => $invoice,
            'billing_address' => $billingAddress,
            'invoice_data' => $invoiceData,
            'is_media' => $isMedia,
            'is_netto' => $isNetto,
            'tax_percent' => $taxPercent,
            'amount' => $amount,
            'net_amount' => $netAmount,
            'tax_amount' => $taxAmount,
            'service_name' => (string) $serviceName,
            'service_period_begin' => $servicePeriodBegin,
            'service_period_end' => $servicePeriodEnd,
        ];
    }

    private function drawHeader(string &$content, bool $isMedia): void
    {
        if ($isMedia) {
            $content .= $this->text(0, 790, 'adametz.media', 21, 'F2', align: 'center');
            $content .= $this->line(180, 778, 415, 778, 0.7);
            $content .= $this->text(0, 762, 'adametz.media, Kevin Adametz, In der Lake 4, 33739 Bielefeld', 9, align: 'center');
            $content .= $this->text(0, 748, 'www.businessportal24.com', 10, 'F2', align: 'center');

            return;
        }

        $content .= $this->text(self::LEFT, 790, 'Stern Consulting GmbH', 19, 'F2');
        $content .= $this->line(self::LEFT, 778, self::RIGHT, 778, 0.7);
        $content .= $this->text(self::LEFT, 760, 'Stern Consulting GmbH * Emser Straße 3 * 10719 Berlin', 10, 'F2');
    }

    /**
     * @param  array<string, mixed>  $data
     */
    private function drawInvoiceBody(string &$content, array $data): void
    {
        /** @var LegacyInvoice $invoice */
        $invoice = $data['invoice'];
        $billingAddress = $data['billing_address'];
        $invoiceDate = $invoice->invoice_date?->format('d.m.Y') ?? 'n/a';
        $invoiceNumber = $invoice->number ?? '#'.$invoice->legacy_id;
        $y = 700.0;

        $content .= $this->text(self::LEFT, $y, 'Rechnungsdatum: '.$invoiceDate, 9);
        $y -= 34;

        foreach ($this->addressLines($invoice, $billingAddress) as $line) {
            $content .= $this->text(self::LEFT, $y, $line, 9);
            $y -= 13;
        }

        $y -= 26;
        $content .= $this->text(self::LEFT, $y, 'Leistung:', 9);
        $y -= 15;
        $content .= $this->text(self::LEFT, $y, $data['service_name'].' auf '.$invoice->legacy_portal->label(), 10, 'F2');
        $y = $this->wrappedText($content, self::LEFT, $y - 16, $this->pressReleaseTitle($data), 9, 360);
        $y -= 6;

        $periodLabel = $data['service_period_begin'] === $data['service_period_end']
            ? 'Leistungsdatum: '.$data['service_period_begin']
            : 'Leistungszeitraum: '.$data['service_period_begin'].' - '.$data['service_period_end'];
        $content .= $this->text(self::LEFT, $y, $periodLabel, 9);
        $y -= 17;
        $content .= $this->text(self::LEFT, $y, 'Rechnungsnummer: '.$invoiceNumber, 10, 'F2');
        $y -= 34;

        $y = $this->invoiceTable($content, self::LEFT, $y, [
            ['Rechnungsstellung:', $invoiceDate, false],
            ['Netto:', $this->formatEuro($data['net_amount']), false],
            $data['is_netto'] ? null : ['MwSt. '.$data['tax_percent'].'%:', $this->formatEuro($data['tax_amount']), false],
            ['Rechnungsbetrag:', $this->formatEuro($data['amount']), true],
        ]);

        $y -= 22;
        foreach ($this->paymentLines($data) as $line) {
            $content .= $this->text(self::LEFT, $y, $line, 9);
            $y -= $line === '' ? 9 : 12;
        }
    }

    private function drawFooter(string &$content, bool $isMedia): void
    {
        $content .= $this->line(self::LEFT, 76, self::RIGHT, 76, 0.5);

        if ($isMedia) {
            $columns = [
                ["adametz.media\nKevin Adametz\nIn der Lake 4\n33739 Bielefeld", 91, 62],
                ["Tel: +49 5206 7076721\nMail: info@businessportal24.com\nSite: www.businessportal24.com", 165, 62],
                ["Bankverbindung\nSparkasse Bielefeld\nIBAN: DE96 4805 0161 0065 0356 02\nBIC: SPBIDE3BXXX", 292, 62],
                ["Steuernummer:\n349 / 5001 / 4350\nUSt-ID: DE298729654", 445, 62],
            ];
        } else {
            $columns = [
                ["Stern Consulting GmbH\nEmser Straße 3\n10719 Berlin\nGF: Thomas Stern", 91, 62],
                ["Tel: +49 (0)30 / 700 9410 0\nFax: +49 (0)30 / 700 9410 44\nMail: info@stern-consulting.de\nSite: www.stern-consulting.de", 185, 62],
                ["Bankverbindung\nHypo Vereinsbank\nBLZ: 10020890\nK-Nr: 22865552", 325, 62],
                ["Registergericht:\nAmtsgericht Charlottenburg\nHRB 134586 B\nUSt-Id-Nr.: DE277693156", 430, 62],
            ];
        }

        foreach ($columns as [$text, $x, $y]) {
            $this->wrappedText($content, $x, $y, $text, 6, 105, 8);
        }
    }

    /**
     * @param  array<string, mixed>  $billingAddress
     * @return list<string>
     */
    private function addressLines(LegacyInvoice $invoice, array $billingAddress): array
    {
        $salutation = trim((string) data_get($billingAddress, 'salutation'));
        $name = trim($salutation.' '.(string) data_get($billingAddress, 'name'));
        $city = trim((string) data_get($billingAddress, 'postal_code').' '.(string) data_get($billingAddress, 'city'));
        $lines = [
            $name,
            (string) data_get($billingAddress, 'title'),
            ...$this->splitLines((string) data_get($billingAddress, 'address')),
            $city,
            (string) data_get($billingAddress, 'country_name'),
            $invoice->user?->profile?->tax_id_number ? 'UID-Nr.: '.$invoice->user->profile->tax_id_number : null,
        ];

        return array_values(array_filter($lines, fn (?string $line): bool => filled($line)));
    }

    /**
     * @param  array<string, mixed>  $data
     */
    private function pressReleaseTitle(array $data): string
    {
        return (string) (
            data_get($data, 'invoice_data.press_release_title')
            ?? data_get($data, 'invoice_data.press_release.name')
            ?? ''
        );
    }

    /**
     * @param  array<int, array{0: string, 1: string, 2: bool}|null>  $rows
     */
    private function invoiceTable(string &$content, float $x, float $y, array $rows): float
    {
        $width = 275.0;
        $rowHeight = 22.0;
        $valueX = $x + 160;

        $content .= $this->line($x, $y, $x + $width, $y, 0.5);
        foreach (array_values(array_filter($rows)) as [$label, $value, $bold]) {
            $y -= $rowHeight;
            $content .= $this->text($x, $y + 7, $label, 9, $bold ? 'F2' : 'F1');
            $content .= $this->text($valueX, $y + 7, $value, 9, $bold ? 'F2' : 'F1');
            $content .= $this->line($x, $y, $x + $width, $y, 0.5);
        }

        return $y;
    }

    /**
     * @param  array<string, mixed>  $data
     * @return list<string>
     */
    private function paymentLines(array $data): array
    {
        /** @var LegacyInvoice $invoice */
        $invoice = $data['invoice'];
        $invoiceNumber = $invoice->number ?? '#'.$invoice->legacy_id;

        if (! $data['is_media']) {
            $lines = [
                'Bitte überweisen Sie den Rechnungsbetrag innerhalb von 7 Werktagen auf unser Geschäftskonto:',
                '',
                'Kontoinhaber: Stern Consulting GmbH',
                'IBAN: DE23100208900022865552',
                'BIC: HYVEDEMM488',
                'Bank: Hypo Vereinsbank',
                '',
                'Als Verwendungszweck geben Sie bitte "Rechungsnummer '.$invoiceNumber.'" an!',
                '',
                'Bitte ignorieren Sie diese Zahlungsaufforderung, falls der Betrag bereits entrichtet wurde.',
            ];
        } else {
            $lines = [
                'Bitte überweisen Sie den Rechnungsbetrag innerhalb von 7 Werktagen auf unser Geschäftskonto:',
                '',
                'Wichtig! Ab Januar 2024 gilt die neue Bankverbindung:',
                '',
                'Kontoinhaber: adametz.media, Kevin Adametz',
                'IBAN: DE96 4805 0161 0065 0356 02',
                'BIC: SPBIDE3BXXX',
                'Bank: Sparkasse Bielefeld',
                '',
                'Als Verwendungszweck geben Sie bitte "Rechungsnummer '.$invoiceNumber.'" an!',
                '',
                'Bitte ignorieren Sie diese Zahlungsaufforderung, falls der Betrag bereits entrichtet wurde.',
            ];
        }

        if ($data['is_netto']) {
            $lines[] = '';
            $lines[] = 'Leistungen im Reverse-Charge Verfahren - Steuerschuldnerschaft des Leistungsempfängers';
        }

        return $lines;
    }

    private function taxPercent(LegacyInvoice $invoice): int
    {
        $invoiceDate = $invoice->invoice_date;

        if ($invoiceDate && $invoiceDate->betweenIncluded(Carbon::parse('2020-07-01'), Carbon::parse('2020-12-31'))) {
            return 16;
        }

        return 19;
    }

    private function formatLegacyDate(mixed $value): string
    {
        if (blank($value) || $value === '0000-00-00' || $value === '0000-00-00 00:00:00') {
            return 'n/a';
        }

        return Carbon::parse((string) $value)->format('d.m.Y');
    }

    private function formatEuro(float $amount): string
    {
        return number_format($amount, 2, ',', '.').' €';
    }

    private function buildPdf(string $content): string
    {
        $objects = [
            "1 0 obj\n<< /Type /Catalog /Pages 2 0 R >>\nendobj\n",
            "2 0 obj\n<< /Type /Pages /Kids [3 0 R] /Count 1 >>\nendobj\n",
            "3 0 obj\n<< /Type /Page /Parent 2 0 R /MediaBox [0 0 ".self::PAGE_WIDTH.' '.self::PAGE_HEIGHT."] /Resources << /Font << /F1 4 0 R /F2 5 0 R >> >> /Contents 6 0 R >>\nendobj\n",
            "4 0 obj\n<< /Type /Font /Subtype /Type1 /BaseFont /Helvetica /Encoding /WinAnsiEncoding >>\nendobj\n",
            "5 0 obj\n<< /Type /Font /Subtype /Type1 /BaseFont /Helvetica-Bold /Encoding /WinAnsiEncoding >>\nendobj\n",
            "6 0 obj\n<< /Length ".strlen($content)." >>\nstream\n{$content}endstream\nendobj\n",
        ];

        $pdf = "%PDF-1.4\n";
        $offsets = [0];

        foreach ($objects as $object) {
            $offsets[] = strlen($pdf);
            $pdf .= $object;
        }

        $xrefOffset = strlen($pdf);
        $pdf .= "xref\n0 ".(count($objects) + 1)."\n";
        $pdf .= "0000000000 65535 f \n";

        foreach (array_slice($offsets, 1) as $offset) {
            $pdf .= sprintf("%010d 00000 n \n", $offset);
        }

        $pdf .= "trailer\n<< /Size ".(count($objects) + 1)." /Root 1 0 R >>\n";
        $pdf .= "startxref\n{$xrefOffset}\n%%EOF\n";

        return $pdf;
    }

    private function escapePdfText(string $text): string
    {
        $encoded = iconv('UTF-8', 'Windows-1252//TRANSLIT//IGNORE', $text);

        return str_replace(['\\', '(', ')'], ['\\\\', '\(', '\)'], $encoded ?: Str::ascii($text));
    }

    private function text(float $x, float $y, string $text, int $size = 9, string $font = 'F1', string $align = 'left'): string
    {
        if ($align === 'center') {
            $x = (self::PAGE_WIDTH - $this->textWidth($text, $size)) / 2;
        }

        return sprintf(
            "BT /%s %d Tf %.2F %.2F Td (%s) Tj ET\n",
            $font,
            $size,
            $x,
            $y,
            $this->escapePdfText($text),
        );
    }

    private function line(float $x1, float $y1, float $x2, float $y2, float $width = 0.5): string
    {
        return sprintf("%.2F w %.2F %.2F m %.2F %.2F l S\n", $width, $x1, $y1, $x2, $y2);
    }

    private function wrappedText(
        string &$content,
        float $x,
        float $y,
        string $text,
        int $size,
        float $width,
        float $lineHeight = 12,
        string $font = 'F1',
    ): float {
        foreach ($this->wrap($text, $width, $size) as $line) {
            if ($line !== '') {
                $content .= $this->text($x, $y, $line, $size, $font);
            }

            $y -= $lineHeight;
        }

        return $y;
    }

    /**
     * @return list<string>
     */
    private function wrap(string $text, float $width, int $size): array
    {
        $lines = [];
        $maxCharacters = max(8, (int) floor($width / ($size * 0.48)));

        foreach ($this->splitLines($text) as $paragraph) {
            if ($paragraph === '') {
                $lines[] = '';

                continue;
            }

            $line = '';
            foreach (preg_split('/\s+/', $paragraph) ?: [] as $word) {
                $candidate = trim($line.' '.$word);
                if ($line !== '' && Str::length($candidate) > $maxCharacters) {
                    $lines[] = $line;
                    $line = $word;

                    continue;
                }

                $line = $candidate;
            }

            if ($line !== '') {
                $lines[] = $line;
            }
        }

        return $lines;
    }

    /**
     * @return list<string>
     */
    private function splitLines(string $text): array
    {
        return explode("\n", str_replace(["\r\n", "\r"], "\n", $text));
    }

    private function textWidth(string $text, int $size): float
    {
        return Str::length($text) * $size * 0.48;
    }
}