lpj/Helpers/PdfHelper.php

<?php

namespace Modules\Lpj\Helpers;

class PdfHelper
{
    /**
     * Format text for PDF output to handle special characters
     *
     * @param string $text
     * @return string
     */
    public static function formatText($text)
    {
        if (empty($text)) {
            return '';
        }

        // Common problematic characters and their safe replacements
        $replacements = [
            '<' => '&lt;',
            '>' => '&gt;',
            '&' => '&amp;',
            '"' => '&quot;',
            "'" => '&#39;',
            '≤' => '&le;',
            '≥' => '&ge;',
            '≠' => '!=',
            '≈' => '~',
            '×' => 'x',
            '÷' => '/',
            '–' => '-',
            '—' => '-',
            '' => '"',
            '' => '"',
            '' => "'",
            '' => "'",
        ];

        // First pass: replace with HTML entities
        $safeText = str_replace(array_keys($replacements), array_values($replacements), $text);

        // Ensure UTF-8 encoding
        if (!mb_check_encoding($safeText, 'UTF-8')) {
            $safeText = mb_convert_encoding($safeText, 'UTF-8', 'auto');
        }

        // Remove any remaining non-ASCII characters that could cause issues
        $safeText = preg_replace('/[^\x20-\x7E\xA0-\xFF]/', '', $safeText);

        return $safeText;
    }

    /**
     * Format mathematical symbols to text representation
     *
     * @param string $text
     * @return string
     */
    public static function formatMathSymbols($text)
    {
        if (empty($text)) {
            return '';
        }

        $mathReplacements = [
            '<' => 'kurang dari',
            '>' => 'lebih dari',
            '<=' => 'kurang dari sama dengan',
            '>=' => 'lebih dari sama dengan',
            '!=' => 'tidak sama dengan',
            '==' => 'sama dengan',
            '≤' => 'kurang dari sama dengan',
            '≥' => 'lebih dari sama dengan',
            '≠' => 'tidak sama dengan',
            '≈' => 'kira-kira',
            '≡' => 'identik dengan',
            '≅' => 'hampir sama dengan',
        ];

        return str_replace(array_keys($mathReplacements), array_values($mathReplacements), $text);
    }
}