Aplikasi-Kehadiran-KTM/app/Support/SimpleXlsx.php

<?php

namespace App\Support;

use ZipArchive;

/**
 * Penjana .xlsx ringan tanpa kebergantungan luar. Setiap nilai sel ditulis
 * sebagai "inline string" supaya nilai seperti No. KP kekal sebagai teks
 * (mengekalkan sengkang / sifar di hadapan). Menyokong berbilang worksheet.
 */
class SimpleXlsx
{
    /** @var array<int,array{name:string,rows:array<int,array<int,scalar|null>>}> */
    private array $sheets = [];

    /**
     * Tambah satu worksheet. Baris pertama dianggap pengepala (huruf tebal).
     *
     * @param  array<int,array<int,scalar|null>>  $rows
     */
    public function addSheet(string $name, array $rows): static
    {
        $this->sheets[] = ['name' => $this->namaSah($name), 'rows' => $rows];

        return $this;
    }

    /**
     * Hasilkan kandungan binari fail .xlsx.
     */
    public function toString(): string
    {
        $tmp = tempnam(sys_get_temp_dir(), 'xlsx');

        $zip = new ZipArchive;
        $zip->open($tmp, ZipArchive::OVERWRITE);

        $zip->addFromString('[Content_Types].xml', $this->contentTypes());
        $zip->addFromString('_rels/.rels', $this->rootRels());
        $zip->addFromString('xl/workbook.xml', $this->workbook());
        $zip->addFromString('xl/_rels/workbook.xml.rels', $this->workbookRels());
        $zip->addFromString('xl/styles.xml', $this->styles());

        foreach ($this->sheets as $i => $sheet) {
            $zip->addFromString('xl/worksheets/sheet'.($i + 1).'.xml', $this->sheetXml($sheet['rows']));
        }

        $zip->close();

        $data = file_get_contents($tmp);
        @unlink($tmp);

        return $data;
    }

    private function namaSah(string $name): string
    {
        $name = preg_replace('/[\\\\\/\*\?\[\]:]/', ' ', $name);

        return mb_substr(trim($name), 0, 31) ?: 'Sheet';
    }

    /**
     * Tukar indeks lajur (0-asas) kepada huruf A, B, … AA.
     */
    private function col(int $index): string
    {
        $letters = '';
        $index++;

        while ($index > 0) {
            $mod = ($index - 1) % 26;
            $letters = chr(65 + $mod).$letters;
            $index = intdiv($index - 1, 26);
        }

        return $letters;
    }

    private function cell(string $ref, string $value, int $style): string
    {
        $v = htmlspecialchars($value, ENT_QUOTES | ENT_XML1, 'UTF-8');
        $s = $style > 0 ? ' s="'.$style.'"' : '';

        return '<c r="'.$ref.'"'.$s.' t="inlineStr"><is><t xml:space="preserve">'.$v.'</t></is></c>';
    }

    /**
     * @param  array<int,array<int,scalar|null>>  $rows
     */
    private function sheetXml(array $rows): string
    {
        $xml = '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>'
            .'<worksheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main"><sheetData>';

        foreach ($rows as $r => $cells) {
            $rowNum = $r + 1;
            $style = $r === 0 ? 1 : 0;
            $xml .= '<row r="'.$rowNum.'">';

            foreach (array_values($cells) as $c => $val) {
                $xml .= $this->cell($this->col($c).$rowNum, (string) $val, $style);
            }

            $xml .= '</row>';
        }

        return $xml.'</sheetData></worksheet>';
    }

    private function contentTypes(): string
    {
        $overrides = '';

        foreach ($this->sheets as $i => $s) {
            $overrides .= '<Override PartName="/xl/worksheets/sheet'.($i + 1).'.xml" '
                .'ContentType="application/vnd.openxmlformats-officedocument.spreadsheetml.worksheet+xml"/>';
        }

        return '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>'
            .'<Types xmlns="http://schemas.openxmlformats.org/package/2006/content-types">'
            .'<Default Extension="rels" ContentType="application/vnd.openxmlformats-package.relationships+xml"/>'
            .'<Default Extension="xml" ContentType="application/xml"/>'
            .'<Override PartName="/xl/workbook.xml" ContentType="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet.main+xml"/>'
            .'<Override PartName="/xl/styles.xml" ContentType="application/vnd.openxmlformats-officedocument.spreadsheetml.styles+xml"/>'
            .$overrides
            .'</Types>';
    }

    private function rootRels(): string
    {
        return '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>'
            .'<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">'
            .'<Relationship Id="rId1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/officeDocument" Target="xl/workbook.xml"/>'
            .'</Relationships>';
    }

    private function workbook(): string
    {
        $sheetsXml = '';

        foreach ($this->sheets as $i => $s) {
            $name = htmlspecialchars($s['name'], ENT_QUOTES | ENT_XML1, 'UTF-8');
            $sheetsXml .= '<sheet name="'.$name.'" sheetId="'.($i + 1).'" r:id="rId'.($i + 1).'"/>';
        }

        return '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>'
            .'<workbook xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" '
            .'xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships">'
            .'<sheets>'.$sheetsXml.'</sheets></workbook>';
    }

    private function workbookRels(): string
    {
        $rels = '';
        $count = count($this->sheets);

        foreach ($this->sheets as $i => $s) {
            $rels .= '<Relationship Id="rId'.($i + 1).'" '
                .'Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/worksheet" '
                .'Target="worksheets/sheet'.($i + 1).'.xml"/>';
        }

        $rels .= '<Relationship Id="rId'.($count + 1).'" '
            .'Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/styles" '
            .'Target="styles.xml"/>';

        return '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>'
            .'<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">'
            .$rels.'</Relationships>';
    }

    private function styles(): string
    {
        return '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>'
            .'<styleSheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main">'
            .'<fonts count="2">'
            .'<font><sz val="11"/><name val="Calibri"/></font>'
            .'<font><b/><sz val="11"/><name val="Calibri"/></font>'
            .'</fonts>'
            .'<fills count="2"><fill><patternFill patternType="none"/></fill><fill><patternFill patternType="gray125"/></fill></fills>'
            .'<borders count="1"><border/></borders>'
            .'<cellStyleXfs count="1"><xf numFmtId="0" fontId="0" fillId="0" borderId="0"/></cellStyleXfs>'
            .'<cellXfs count="2">'
            .'<xf numFmtId="0" fontId="0" fillId="0" borderId="0" xfId="0"/>'
            .'<xf numFmtId="0" fontId="1" fillId="0" borderId="0" xfId="0" applyFont="1"/>'
            .'</cellXfs>'
            .'</styleSheet>';
    }
}