sequenceDiagram
    participant User as 用户
    participant CLI as TodoCLI
    participant Manager as TodoManager
    participant Storage as Storage
    participant File as JSON文件
    User->>CLI: python main.py add "任务标题" -d "描述" -due 2025-01-01
    CLI->>CLI: _setup_parser() 解析参数
    CLI->>CLI: _handle_add(args)
    CLI->>Manager: add(title, description, due_date)
    Manager->>Manager: 生成新TodoItem，设置id=next_id
    Manager->>Manager: 将item加入items列表
    Manager->>Manager: _save()
    Manager->>Storage: save([item.to_dict() for item in items])
    Storage->>File: 写入JSON文件
    File-->>Storage: 成功
    Storage-->>Manager: None
    Manager-->>CLI: 返回新TodoItem
    CLI-->>User: 打印添加成功信息

    User->>CLI: python main.py list
    CLI->>CLI: _handle_list(args)
    CLI->>Manager: list_all()
    Manager->>Manager: 返回items列表
    Manager-->>CLI: list[TodoItem]
    CLI->>CLI: 格式化输出表格
    CLI-->>User: 显示所有任务

    User->>CLI: python main.py done 1
    CLI->>CLI: _handle_done(args)
    CLI->>Manager: mark_done(1)
    Manager->>Manager: _find_by_id(1) -> item
    Manager->>Manager: item.completed = True
    Manager->>Manager: _save()
    Manager-->>CLI: True
    CLI-->>User: 打印标记成功

    User->>CLI: python main.py delete 1
    CLI->>CLI: _handle_delete(args)
    CLI->>Manager: delete(1)
    Manager->>Manager: _find_by_id(1) -> item
    Manager->>Manager: 从items中移除
    Manager->>Manager: _save()
    Manager-->>CLI: True
    CLI-->>User: 打印删除成功

    User->>CLI: python main.py edit 1 --title "新标题" --description "新描述"
    CLI->>CLI: _handle_edit(args)
    CLI->>Manager: edit(1, title="新标题", description="新描述")
    Manager->>Manager: _find_by_id(1) -> item
    Manager->>Manager: 更新item属性
    Manager->>Manager: _save()
    Manager-->>CLI: True
    CLI-->>User: 打印编辑成功