初始化仓库及v1.0.0提交

app/Config/Database.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace App\Config;
+
+use PDO;
+use PDOException;
+
+class Database
+{
+    private static ?PDO $instance = null;
+
+    private function __construct()
+    {
+        $configPath = dirname(__DIR__, 2) . '/config/db-config.json';
+
+        if (!file_exists($configPath)) {
+            throw new PDOException('数据库配置文件不存在');
+        }
+
+        $config = json_decode(file_get_contents($configPath), true);
+
+        $dsn = "mysql:host={$config['host']};port={$config['port']};dbname={$config['dbname']};charset=utf8mb4";
+
+        self::$instance = new PDO($dsn, $config['user'], $config['password'], [
+            PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
+            PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
+            PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8mb4",
+        ]);
+    }
+
+    public static function getInstance(): PDO
+    {
+        if (self::$instance === null) {
+            new self();
+        }
+
+        return self::$instance;
+    }
+}