"""Local-only MCP server over stdio."""

from __future__ import annotations

import os
import sys

from mcp.server.fastmcp import FastMCP

from mcp_server import tools


def _is_local_only() -> bool:
    return os.environ.get("MCP_ALLOW_REMOTE", "").lower() not in {"1", "true", "yes"}


def _guard_local() -> None:
    if not _is_local_only():
        return
    if os.environ.get("SSH_CONNECTION"):
        sys.stderr.write("Remote access denied. Unset SSH_CONNECTION or set MCP_ALLOW_REMOTE.\n")
        sys.exit(1)


mcp = FastMCP("NixOS Repo MCP", json_response=True)


@mcp.tool(name="show-constitution")
def show_constitution() -> dict[str, object]:
    """Display repository AI constitution for rule lookup."""
    return tools.invoke_tool("show-constitution", {})


@mcp.tool(name="list-playbooks")
def list_playbooks() -> dict[str, object]:
    """List available playbooks under docs/playbooks."""
    return tools.invoke_tool("list-playbooks", {})


@mcp.tool(name="show-reference")
def show_reference() -> dict[str, object]:
    """Show docs/reference/index.md for navigation guidance."""
    return tools.invoke_tool("show-reference", {})


@mcp.tool(name="search-docs")
def search_docs(query: str) -> dict[str, object]:
    """Search docs for a query string."""
    return tools.invoke_tool("search-docs", {"query": query})


@mcp.tool(name="list-mcp-tasks")
def list_mcp_tasks() -> dict[str, object]:
    """Show MCP feature task list from specs."""
    return tools.invoke_tool("list-mcp-tasks", {})


@mcp.tool(name="sync-docs")
def sync_docs() -> dict[str, object]:
    """Compare tool catalog against documented anchors."""
    return tools.invoke_tool("sync-docs", {})


def main() -> None:
    """Run the MCP server in stdio mode."""
    _guard_local()
    mcp.run(transport="stdio")


if __name__ == "__main__":
    main()