"""
Virtual file system used by the deep agent.
It stores files in memory and can be dumped to the real file system.
"""

import os
from pathlib import Path
from typing import Dict, Optional

class VirtualFileSystem:
    """A simple in‑memory file system.

    Files are stored as a mapping from a relative path to its content.
    """

    def __init__(self, base_dir: str = "virtual_fs"):
        self.base_dir = Path(base_dir)
        self.files: Dict[str, str] = {}

    def write_file(self, path: str, content: str) -> None:
        norm_path = Path(path).as_posix()
        self.files[norm_path] = content

    def read_file(self, path: str) -> Optional[str]:
        norm_path = Path(path).as_posix()
        return self.files.get(norm_path)

    def list_files(self) -> Dict[str, str]:
        return dict(self.files)

    def dump_to_real_fs(self, real_root: str = "real_fs") -> None:
        real_root_path = Path(real_root)
        for rel_path, content in self.files.items():
            file_path = real_root_path / rel_path
            file_path.parent.mkdir(parents=True, exist_ok=True)
            file_path.write_text(content, encoding="utf-8")

    def __repr__(self) -> str:
        return f"VirtualFileSystem(files={list(self.files.keys())})"