defmodule PhoenixKitWeb.DBSyncSocket do
  @moduledoc """
  Socket for DB Sync module.

  This socket accepts external WebSocket connections from sender sites
  that want to connect using a connection code.

  ## Authentication

  Senders connect by providing:
  - `code` - The 8-character connection code from the receiver

  The socket validates the code and associates the connection with
  the receiver's session.

  ## Example Connection

      // On sender site (using websockex or JS WebSocket)
      const socket = new WebSocket("wss://receiver-site.com/db-sync/websocket?code=ABC12345")
  """

  use Phoenix.Socket
  require Logger

  alias PhoenixKit.DBSync

  channel "transfer:*", PhoenixKitWeb.DBSyncChannel

  @impl true
  def connect(%{"code" => code}, socket, _connect_info) do
    # Check if DB Sync is enabled
    if DBSync.enabled?() do
      # Validate the connection code
      case DBSync.validate_code(code) do
        {:ok, session} ->
          Logger.info("DBSync: Sender connected with code #{code}")

          socket =
            socket
            |> assign(:session_code, code)
            |> assign(:session, session)
            |> assign(:direction, :sender)

          {:ok, socket}

        {:error, :invalid_code} ->
          Logger.warning("DBSync: Invalid code attempt: #{code}")
          {:error, :invalid_code}

        {:error, :already_used} ->
          Logger.warning("DBSync: Code already used: #{code}")
          {:error, :already_used}
      end
    else
      Logger.warning("DBSync: Connection attempt but module is disabled")
      {:error, :module_disabled}
    end
  end

  def connect(_params, _socket, _connect_info) do
    Logger.warning("DBSync: Connection attempt without code")
    {:error, :missing_code}
  end

  @impl true
  def id(socket), do: "db_sync:#{socket.assigns.session_code}"
end