from pathlib import Path

from fastmcp import FastMCP
from starlette.middleware import Middleware
from starlette.middleware.cors import CORSMiddleware
from starlette.requests import Request
from starlette.responses import JSONResponse
import uvicorn


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


# Streamable HTTP MCP server.
mcp = FastMCP("FilePersistenceMCP")


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


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


@mcp.custom_route("/health", methods=["GET"])
async def http_health(_: Request) -> JSONResponse:
    return JSONResponse(
        {
            "status": "ok",
            "server": "FilePersistenceMCP",
            "transport": "streamable-http",
        }
    )


if __name__ == "__main__":
    app = mcp.http_app(
        path="/mcp",
        middleware=[
            Middleware(
                CORSMiddleware,
                allow_origins=["*"],
                allow_methods=["*"],
                allow_headers=["*"],
            )
        ],
        stateless_http=True,
    )
    uvicorn.run(app, host="0.0.0.0", port=8001)