<?php
/*
 *  GNUfault.org - GNUfault's website
 *  Copyright (C) 2026  Connor Thomson
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

function strip_comments(string $html): string {
    return preg_replace('/<!--(?!\[if).*?-->/s', '', $html);
}

function tidy(string $html): string {
    $html = preg_replace('/[^\S\n]+$/m', '', $html);
    $html = preg_replace('/\n{3,}/', "\n\n", $html);

    return trim($html, "\n");
}

function dedent(string $html): string {
    $width = null;

    foreach (explode("\n", $html) as $line) {
        if (trim($line) === '') {
            continue;
        }

        $leading = strlen($line) - strlen(ltrim($line, " \t"));

        if ($width === null || $leading < $width) {
            $width = $leading;
        }
    }

    if (!$width) {
        return $html;
    }

    return preg_replace('/^[ \t]{1,' . $width . '}/m', '', $html);
}

function indent(string $html, string $indent): string {
    $html = dedent($html);

    if ($indent === '') {
        return $html;
    }

    $lines = explode("\n", $html);

    foreach ($lines as $number => $line) {
        if ($line !== '') {
            $lines[$number] = $indent . $line;
        }
    }

    return implode("\n", $lines);
}

function preprocess(string $html): string {
    return tidy(strip_comments($html));
}

function import(string $path): string {
    if (!file_exists($path)) {
        return '';
    }

    return preprocess(file_get_contents($path));
}

?>