feat: 增加 nix 支持

.envrc

@@ -0,0 +1 @@
+use flake

.gitignore

@@ -192,3 +192,6 @@ jieba.cache
 
 # vscode
 /.vscode
+
+# direnv
+/.direnv

flake.nix

@@ -0,0 +1,52 @@
+{
+  description = "MaiMBot Nix Dev Env";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { self, nixpkgs, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = import nixpkgs {
+          inherit system;
+        };
+
+        # 读取 requirements.txt 文件
+        requirementsFile = builtins.readFile ./requirements.txt;
+
+        # 解析 requirements.txt 文件，提取包名
+        parseRequirements = content:
+          let
+            lines = builtins.split "\n" content;
+            # 过滤掉空行和注释
+            filteredLines = builtins.filter (line:
+              line != "" && !(builtins.match "^ *#.*" line)
+            ) lines;
+            # 提取包名（去掉版本号）
+            packageNames = builtins.map (line:
+              builtins.head (builtins.split "[=<>]" line)
+            ) filteredLines;
+          in
+          packageNames;
+
+        # 获取 requirements.txt 中的包名列表
+        requirements = parseRequirements requirementsFile;
+
+        # 动态生成 Python 环境
+        pythonEnv = pkgs.python3.withPackages (ps:
+          builtins.map (pkg: ps.${pkg}) requirements
+        );
+      in
+      {
+        devShell = pkgs.mkShell {
+          buildInputs = [ pythonEnv ];
+
+          shellHook = ''
+            echo "Python environment is ready!"
+          '';
+        };
+      }
+    );
+}