"""Tool implementations used by the Deep Agent.

The tools are simple wrappers around the virtual file system and a
web‑search helper.  They expose a ``name`` and ``description`` that are
used by the LangChain agent.
"""

from __future__ import annotations

from typing import Dict, Any

from langchain_core.tools import BaseTool
from langchain_ollama import OllamaEmbeddings
from langchain_community.tools.tavily_search import TavilySearchResults

from virtual_fs import VirtualFileSystem

# ---------------------------------------------------------------------------
# WebSearch tool
# ---------------------------------------------------------------------------

class WebSearch(BaseTool):
    """Search the web using Tavily.

    The tool returns a short string containing the top results.
    """

    name: str = "web_search"
    description: str = "Search the web for information. Input should be a query."

    def _run(self, query: str) -> str:
        tavily = TavilySearchResults(max_results=3)
        results = tavily.run(query)
        return "\n".join(f"{i+1}. {r['title']} – {r['url']}" for i, r in enumerate(results))

    def _arun(self, query: str) -> str:  # pragma: no cover
        return self._run(query)

# ---------------------------------------------------------------------------
# CreateVirtualFile tool
# ---------------------------------------------------------------------------

class CreateVirtualFile(BaseTool):
    """Create or overwrite a virtual file.

    Input format: ``filename:content``.  The tool splits on the first
    colon and stores the content in the shared virtual file system.
    """

    name: str = "create_virtual_file"
    description: str = (
        "Create or overwrite a virtual file. Input format: 'filename:content'."
    )

    def __init__(self, vfs: VirtualFileSystem):
        super().__init__()
        self.vfs = vfs

    def _run(self, input_text: str) -> str:
        if ":" not in input_text:
            raise ValueError("Input must be in the form 'filename:content'")
        name, content = input_text.split(":", 1)
        self.vfs.create_file(name.strip(), content.strip())
        return f"File '{name.strip()}' created with {len(content.strip())} characters."

    def _arun(self, input_text: str) -> str:  # pragma: no cover
        return self._run(input_text)

# ---------------------------------------------------------------------------
# ExportVirtualFiles tool
# ---------------------------------------------------------------------------

class ExportVirtualFiles(BaseTool):
    """Export all virtual files to the real filesystem.

    Input can optionally specify a target directory.  If omitted, the
    current working directory is used.
    """

    name: str = "export_virtual_files"
    description: str = (
        "Export all virtual files to disk. Input is an optional directory path."
    )

    def __init__(self, vfs: VirtualFileSystem):
        super().__init__()
        self.vfs = vfs

    def _run(self, input_text: str | None = None) -> str:
        target = input_text.strip() if input_text else "."
        self.vfs.export_to_disk(target)
        return f"Exported {len(self.vfs.files)} files to {target}"

    def _arun(self, input_text: str | None = None) -> str:  # pragma: no cover
        return self._run(input_text)