feat: add wiki

wiki/page.php

@@ -0,0 +1,42 @@
+<?php
+include '../header.php';
+include '../parsedown/Parsedown.php';
+include '../parsedown-extra/ParsedownExtra.php';
+
+$Parsedown = new Parsedown();
+$Parsedown->setMarkupEscaped(true);
+$Extra = new ParsedownExtra();
+
+$article = $_GET['article'] ?? '';
+$article = basename($article); 
+
+$path = __DIR__ . "/source/{$article}.md";
+if (!is_file($path)) {
+  http_response_code(404);
+  exit;
+}
+
+$raw = file_get_contents($path);
+
+$title = preg_match("/^title:\s*(.*)$/mi", $raw, $m) ? trim($m[1]) : ucfirst($article);
+$authors = preg_match("/^authors:\s*(.*)$/mi", $raw, $m) ? trim($m[1]) : ucfirst($article);
+
+$body = preg_replace("/^(title|category|authors):[^\r\n]*\r?\n/m", "", $raw);
+
+$html = $Extra->text($body); 
+?>
+
+<div id="top-bar">
+  <h1>> <?php echo htmlspecialchars($title); ?></h1>
+  <p>osoby autorskie: <a href=/~<?php echo $authors ?>>~<?php echo $authors ?></a></p>
+</div>
+
+<article id="content">
+  <?php echo $html; ?>
+</article>
+
+<?php
+
+include '../footer.php'
+
+?>