✨ feat: 添加文档功能和页面模板

web/docs.php

@@ -0,0 +1,58 @@
+<?php
+require_once('./include/db_info.inc.php');
+require_once('./include/setlang.php');
+require_once('./include/const.inc.php');
+
+$docs_dir = __DIR__ . '/doc';
+$doc_entries = array();
+
+if (is_dir($docs_dir)) {
+    $doc_files = glob($docs_dir . '/*.md');
+    if ($doc_files !== false) {
+        sort($doc_files, SORT_NATURAL | SORT_FLAG_CASE);
+        foreach ($doc_files as $doc_file) {
+            $doc_entries[] = array(
+                'file' => basename($doc_file),
+                'title' => preg_replace('/\.md$/i', '', basename($doc_file))
+            );
+        }
+    }
+}
+
+$selected_file = '';
+if (isset($_GET['file'])) {
+    $selected_file = basename($_GET['file']);
+}
+
+if (empty($selected_file) && !empty($doc_entries)) {
+    $selected_file = $doc_entries[0]['file'];
+}
+
+$selected_title = '文档';
+$selected_markdown = '';
+
+if (!empty($selected_file)) {
+    $selected_path = realpath($docs_dir . DIRECTORY_SEPARATOR . $selected_file);
+    $docs_root = realpath($docs_dir);
+
+    if (
+        $selected_path !== false &&
+        $docs_root !== false &&
+        strpos($selected_path, $docs_root . DIRECTORY_SEPARATOR) === 0 &&
+        is_file($selected_path) &&
+        preg_match('/\.md$/i', $selected_path)
+    ) {
+        $selected_markdown = file_get_contents($selected_path);
+        if ($selected_markdown === false) {
+            $selected_markdown = '';
+        } else {
+            $selected_markdown = preg_replace('/^\xEF\xBB\xBF/', '', $selected_markdown);
+        }
+        $selected_title = preg_replace('/\.md$/i', '', basename($selected_path));
+    }
+}
+
+$show_title = $selected_title . ' - ' . $OJ_NAME;
+
+require('template/' . $OJ_TEMPLATE . '/docs.php');
+?>