import ast

class UnusedVarChecker(ast.NodeVisitor):
    def __init__(self):
        self.defined_vars = set()  # 存儲已定義的變量
        self.used_vars = set()     # 存儲已使用的變量

    def visit_Assign(self, node):
        # 記錄賦值語句左側的變量名（如 x = 10）
        for target in node.targets:
            if isinstance(target, ast.Name):
                self.defined_vars.add(target.id)
        self.generic_visit(node)  # 繼續(xù)遍歷子節(jié)點

    def visit_Name(self, node):
        # 記錄變量被引用的情況（如 print(x)）
        if isinstance(node.ctx, ast.Load):  # 僅統(tǒng)計讀取操作
            self.used_vars.add(node.id)
        self.generic_visit(node)

    def report(self):
        unused = self.defined_vars - self.used_vars
        print(f"未使用的變量: {unused}")

# 測試代碼
code = """
x = 10
y = 20
print(y)
"""

tree = ast.parse(code)
checker = UnusedVarChecker()
checker.visit(tree)
checker.report()  # 輸出：未使用的變量: {'x'}

import ast
import astor  # 第三方庫，用于將 AST 轉回代碼

class PrintToLoggerTransformer(ast.NodeTransformer):
    def visit_Call(self, node):
        # 檢查是否是 print 函數(shù)調用
        if isinstance(node.func, ast.Name) and node.func.id == 'print':
            # 構造新的函數(shù)調用節(jié)點：logger.info(*args)
            new_func = ast.Attribute(
                value=ast.Name(id='logger', ctx=ast.Load()),
                attr='info',
                ctx=ast.Load()
            )
            node.func = new_func
        return node

# 原始代碼
code = """
print('Hello')
x = 5
print('World')
"""

tree = ast.parse(code)
transformer = PrintToLoggerTransformer()
new_tree = transformer.visit(tree)

# 生成修改后的代碼
new_code = astor.to_source(new_tree)
print(new_code)
# 輸出：
# logger.info('Hello')
# x = 5
# logger.info('World')

import ast

class FunctionExtractor(ast.NodeVisitor):
    def __init__(self):
        self.functions = []

    def visit_FunctionDef(self, node):
        # 提取函數(shù)名
        func_name = node.name
        # 提取參數(shù)列表
        args = [arg.arg for arg in node.args.args]
        # 提取返回類型注解
        returns = ast.unparse(node.returns) if node.returns else None
        self.functions.append({
            'name': func_name,
            'args': args,
            'returns': returns
        })
        self.generic_visit(node)

# 測試代碼
code = """
def add(a: int, b: int) -> int:
    return a + b

def greet(name: str) -> None:
    print(f"Hello, {name}!")
"""

tree = ast.parse(code)
extractor = FunctionExtractor()
extractor.visit(tree)
print(extractor.functions)
# 輸出：
# [
#   {'name': 'add', 'args': ['a', 'b'], 'returns': 'int'},
#   {'name': 'greet', 'args': ['name'], 'returns': 'None'}
# ]