import os
import json
from typing import Dict
from duckduckgo_search import DDGS

# In‑memory virtual file system
VIRTUAL_FS: Dict[str, str] = {}


def web_search(query: str) -> str:
    """Search the web via DuckDuckGo and return top‑5 results.

    Each result is formatted as ``Title`` + ``Snippet`` + ``URL``.
    The function returns a single string with results separated by newlines.
    """
    results = []
    with DDGS() as ddgs:
        for r in ddgs.text(query, max_results=5):
            title = r.get("title", "")
            body = r.get("body", "")
            href = r.get("href", "")
            results.append(f"{title}\n{body}\n{href}")
    return "\n\n".join(results)


def create_virtual_file(filename: str, content: str) -> str:
    """Create or overwrite a file in the virtual file system.

    Parameters
    ----------
    filename: str
        Name of the file to create.
    content: str
        File content.
    """
    VIRTUAL_FS[filename] = content
    return f"File {filename} created with {len(content)} characters."


def list_virtual_files() -> str:
    """Return a list of filenames stored in the virtual file system."""
    if not VIRTUAL_FS:
        return "No files in virtual FS."
    return "\n".join(sorted(VIRTUAL_FS.keys()))


def export_files(output_dir: str = "output") -> str:
    """Export all virtual files to the local filesystem.

    Parameters
    ----------
    output_dir: str
        Directory where files will be written. The directory is created if it
        does not exist.
    """
    os.makedirs(output_dir, exist_ok=True)
    for fname, content in VIRTUAL_FS.items():
        path = os.path.join(output_dir, fname)
        with open(path, "w", encoding="utf-8") as f:
            f.write(content)
    return f"Exported {len(VIRTUAL_FS)} files to {output_dir}."

# End of tools module