defmodule Phoenix.SocketClient.Telemetry do
  @moduledoc """
  Telemetry integration for Phoenix.SocketClient.

  This module provides telemetry events for monitoring socket connections,
  channel joins/leaves, message handling, and connection lifecycle events.
  """

  @doc """
  Emits a telemetry event with the given name and measurements/metadata.
  """
  @spec emit_event(list(atom() | String.t()), map(), map()) :: :ok
  def emit_event(event_name, measurements \\ %{}, metadata \\ %{}) do
    :telemetry.execute(event_name, measurements, metadata)
  end

  @doc """
  Emits socket connection event.
  """
  @spec socket_connected(pid(), String.t(), map()) :: :ok
  def socket_connected(pid, url, _metadata \\ %{}) do
    emit_event([:phoenix_socket_client, :socket, :connected], %{}, %{
      pid: pid,
      url: url,
      timestamp: System.system_time(:millisecond)
    })
  end

  @doc """
  Emits socket disconnection event.
  """
  @spec socket_disconnected(pid(), String.t(), atom(), map()) :: :ok
  def socket_disconnected(pid, url, reason, _metadata \\ %{}) do
    emit_event([:phoenix_socket_client, :socket, :disconnected], %{}, %{
      pid: pid,
      url: url,
      reason: reason,
      timestamp: System.system_time(:millisecond)
    })
  end

  @doc """
  Emits socket connection attempt event.
  """
  @spec socket_connecting(pid(), String.t(), map()) :: :ok
  def socket_connecting(pid, url, _metadata \\ %{}) do
    emit_event([:phoenix_socket_client, :socket, :connecting], %{}, %{
      pid: pid,
      url: url,
      timestamp: System.system_time(:millisecond)
    })
  end

  @doc """
  Emits socket connection error event.
  """
  @spec socket_connection_error(pid(), String.t(), any(), map()) :: :ok
  def socket_connection_error(pid, url, error, _metadata \\ %{}) do
    emit_event([:phoenix_socket_client, :socket, :connection_error], %{}, %{
      pid: pid,
      url: url,
      error: error,
      timestamp: System.system_time(:millisecond)
    })
  end

  @doc """
  Emits channel join event.
  """
  @spec channel_joined(pid(), String.t(), String.t(), map(), map()) :: :ok
  def channel_joined(pid, topic, channel_pid, response, _metadata \\ %{}) do
    emit_event([:phoenix_socket_client, :channel, :joined], %{}, %{
      pid: pid,
      topic: topic,
      channel_pid: channel_pid,
      response: response,
      timestamp: System.system_time(:millisecond)
    })
  end

  @doc """
  Emits channel join error event.
  """
  @spec channel_join_error(pid(), String.t(), any(), map()) :: :ok
  def channel_join_error(pid, topic, error, _metadata \\ %{}) do
    emit_event([:phoenix_socket_client, :channel, :join_error], %{}, %{
      pid: pid,
      topic: topic,
      error: error,
      timestamp: System.system_time(:millisecond)
    })
  end

  @doc """
  Emits channel leave event.
  """
  @spec channel_left(pid(), String.t(), String.t(), map()) :: :ok
  def channel_left(pid, topic, reason, _metadata \\ %{}) do
    emit_event([:phoenix_socket_client, :channel, :left], %{}, %{
      pid: pid,
      topic: topic,
      reason: reason,
      timestamp: System.system_time(:millisecond)
    })
  end

  @doc """
  Emits message sent event.
  """
  @spec message_sent(pid(), String.t(), String.t(), map(), map()) :: :ok
  def message_sent(pid, topic, event, payload, _metadata \\ %{}) do
    emit_event([:phoenix_socket_client, :message, :sent], %{}, %{
      pid: pid,
      topic: topic,
      event: event,
      payload: payload,
      timestamp: System.system_time(:millisecond)
    })
  end

  @doc """
  Emits message received event.
  """
  @spec message_received(pid(), String.t(), String.t(), map(), map()) :: :ok
  def message_received(pid, topic, event, payload, _metadata \\ %{}) do
    emit_event([:phoenix_socket_client, :message, :received], %{}, %{
      pid: pid,
      topic: topic,
      event: event,
      payload: payload,
      timestamp: System.system_time(:millisecond)
    })
  end

  @doc """
  Emits heartbeat event.
  """
  @spec heartbeat_sent(pid(), String.t(), map()) :: :ok
  def heartbeat_sent(pid, url, _metadata \\ %{}) do
    emit_event([:phoenix_socket_client, :socket, :heartbeat], %{}, %{
      pid: pid,
      url: url,
      timestamp: System.system_time(:millisecond)
    })
  end

  @doc """
  Emits reconnection attempt event.
  """
  @spec reconnecting(pid(), String.t(), integer(), map()) :: :ok
  def reconnecting(pid, url, attempt, _metadata \\ %{}) do
    emit_event([:phoenix_socket_client, :socket, :reconnecting], %{}, %{
      pid: pid,
      url: url,
      attempt: attempt,
      timestamp: System.system_time(:millisecond)
    })
  end

  @doc """
  Emits debug event for socket lifecycle debugging.
  """
  @spec debug(pid(), String.t(), String.t(), map()) :: :ok
  def debug(pid, message, url \\ nil, metadata \\ %{}) do
    emit_event([:phoenix_socket_client, :debug], %{}, %{
      pid: pid,
      message: message,
      url: url,
      metadata: metadata,
      timestamp: System.system_time(:millisecond)
    })
  end

  @doc """
  Attaches a telemetry handler for debugging purposes.

  ## Example

      Phoenix.SocketClient.Telemetry.attach_debug_handler()
  """
  @spec attach_debug_handler() :: :ok
  def attach_debug_handler do
    :telemetry.attach_many(
      "phoenix-socket-client-debug",
      [
        [:phoenix_socket_client, :socket, :connected],
        [:phoenix_socket_client, :socket, :disconnected],
        [:phoenix_socket_client, :socket, :connecting],
        [:phoenix_socket_client, :socket, :connection_error],
        [:phoenix_socket_client, :channel, :joined],
        [:phoenix_socket_client, :channel, :join_error],
        [:phoenix_socket_client, :channel, :left],
        [:phoenix_socket_client, :message, :sent],
        [:phoenix_socket_client, :message, :received],
        [:phoenix_socket_client, :socket, :heartbeat],
        [:phoenix_socket_client, :socket, :reconnecting],
        [:phoenix_socket_client, :debug]
      ],
      &debug_handler/4,
      %{}
    )
  end

  @doc """
  Detaches the debug handler.
  """
  @spec detach_debug_handler() :: :ok
  def detach_debug_handler do
    :telemetry.detach("phoenix-socket-client-debug")
  end

  defp debug_handler(event_name, measurements, metadata, _config) do
    IO.inspect({event_name, measurements, metadata}, label: "[Phoenix.SocketClient] Telemetry")
  end
end