from pathlib import Path

from fastmcp import FastMCP


ROOT_DIR = Path(__file__).resolve().parent
UPLOAD_DIR = ROOT_DIR / "uploads"
UPLOAD_DIR.mkdir(exist_ok=True)


mcp = FastMCP("FilePersistenceSTDIO")


@mcp.tool
def health() -> dict:
    """Return basic server health information."""
    return {
        "status": "ok",
        "server": "FilePersistenceSTDIO",
        "transport": "stdio",
        "uploads_dir": str(UPLOAD_DIR),
    }


@mcp.tool
def list_uploaded_files() -> dict:
    """List files currently stored in the uploads directory."""
    files = sorted(path.name for path in UPLOAD_DIR.iterdir() if path.is_file())
    return {
        "count": len(files),
        "files": files,
    }


@mcp.tool
def file_info(filename: str) -> dict:
    """Return metadata for one uploaded file."""
    path = (UPLOAD_DIR / filename).resolve()
    if path.parent != UPLOAD_DIR.resolve() or not path.exists() or not path.is_file():
        raise FileNotFoundError(f"File not found: {filename}")

    stat = path.stat()
    return {
        "filename": path.name,
        "size_bytes": stat.st_size,
        "absolute_path": str(path),
    }


if __name__ == "__main__":
    mcp.run(transport="stdio")