<?php

namespace App\Services\Billing\Concerns;

use Illuminate\Support\Str;

/**
 * Minimaler PDF-Zeichensatz (PDF 1.4, Helvetica, WinAnsi) ohne externe
 * Bibliothek — gemeinsam genutzt vom Archiv-Renderer (Legacy) und dem
 * MAN-Rechnungs-Renderer. Koordinaten in PDF-Punkten, Ursprung unten links.
 */
trait DrawsPdf
{
    protected const PAGE_WIDTH = 595;

    protected const PAGE_HEIGHT = 842;

    protected const LEFT = 91;

    protected const RIGHT = 524;

    /**
     * @param  array<int, array{0: string, 1: string, 2: bool}|null>  $rows
     */
    protected function invoiceTable(string &$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;
    }

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

    protected 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;
    }

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

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

    protected 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),
        );
    }

    protected 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);
    }

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

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