"""Command message/response helpers shared by sync and async clients."""
import json
import os
import uuid
from typing import Any

from browser_cli import transport
from browser_cli.endpoints import _normalize_endpoint
from browser_cli.errors import BrowserNotConnected

def base_message(command: str, args: dict | None) -> dict:
  return {"id": str(uuid.uuid4()), "command": command, "args": args or {}}

def requested_target(profile: str | None, remote: str | None) -> tuple[str | None, str | None]:
  requested_profile = profile or os.environ.get("BROWSER_CLI_PROFILE")
  remote_endpoint = remote or os.environ.get("BROWSER_CLI_REMOTE")
  return requested_profile, _normalize_endpoint(remote_endpoint) if remote_endpoint else None

def encode_payload(msg: dict) -> bytes:
  return json.dumps(msg).encode("utf-8")

def decode_response(response: bytes | None) -> Any:
  if response is None:
    raise ConnectionError("Connection closed before full response received")
  result = transport.decode_response(response)
  if not result.get("success", True):
    raise RuntimeError(result.get("error", "unknown error from browser"))
  return result.get("data")

def local_connection_error(profile: str | None) -> BrowserNotConnected:
  profile_hint = f" (profile: {profile})" if profile else ""
  return BrowserNotConnected(
    f"Cannot connect to browser{profile_hint}.\n"
    "Make sure:\n"
    "  1. The browser-cli extension is installed and enabled\n"
    "  2. The native host is registered: uv run browser-cli install <browser>\n"
    "  3. Your browser is running\n"
    "  Tip: use BROWSER_CLI_PROFILE=<name> to select a specific profile"
  )

def remote_connection_error(remote_endpoint: str) -> BrowserNotConnected:
  return BrowserNotConnected(
    f"Cannot connect to remote browser at {remote_endpoint}.\n"
    "Make sure browser-cli serve is running on the remote host."
  )