defmodule GeolocationClient do
  @moduledoc """
  Client for Google Geolocation API
  """

  @base_url "https://www.googleapis.com/"

  @doc """
  Set API key
  """
  @spec set_api_key(String.t()) :: :ok
  def set_api_key(key) do
    Application.put_env(:geolocation_client, :api_key, key)
  end

  @doc """
  Geolocate from a list of MAC addresses
  """
  @spec geolocate_from_mac_addresses([GeolocationClient.Entities.MacAddress.t()], boolean()) :: GeolocationClient.Entities.LatLon.t() | {:error, any()}
  def geolocate_from_mac_addresses(mac_addresses, consider_ip \\ false) when is_list(mac_addresses) do
    # Implementation would go here
    url = "#{@base_url}geolocation/v1/geolocate?key=#{Application.get_env(:geolocation_client, :api_key)}"

    body = %{
      "considerIp" => consider_ip,
      "wifiAccessPoints" => Enum.map(mac_addresses, fn mac ->
        %{
          "macAddress" => mac.mac_address,
          "signalStrength" => mac.signal_strength
        }
      end)
    }

    case Req.post(url, json: body) do
      {:ok, %Req.Response{status: 200, body: %{"location" => location, "accuracy" => accuracy}}} ->
        %GeolocationClient.Entities.LatLon{
          latitude: location["lat"],
          longitude: location["lng"],
          accuracy: accuracy
        }

      {:ok, %Req.Response{status: status, body: body}} ->
        {:error, %{status: status, body: body}}

      {:error, reason} ->
        {:error, reason}
    end
  end

  @doc """
  Get altitude for given latitude and longitude
  """
  @spec get_altitude(GeolocationClient.Entities.LatLon.t()) :: float() | {:error, any()}
  def get_altitude(%GeolocationClient.Entities.LatLon{latitude: lat, longitude: lon}) do
    # Implementation would go here
    url = "https://maps.googleapis.com/maps/api/elevation/json?locations=#{lat}%2C#{lon}&key=#{Application.get_env(:geolocation_client, :api_key)}"

    case Req.get(url) do
      {:ok, %Req.Response{status: 200, body: %{"results" => [%{"elevation" => elevation} | _]}}} ->
        elevation

      {:ok, %Req.Response{status: status, body: body}} ->
        {:error, %{status: status, body: body}}

      {:error, reason} ->
        {:error, reason}
    end
  end

  @doc """
  Geolocate from mac addresses and get full location (LLA)
  """
  @spec geolocate_full_location([GeolocationClient.Entities.MacAddress.t()], boolean()) :: GeolocationClient.Entities.Location.t() | {:error, any()}
  def geolocate_full_location(mac_addresses, consider_ip \\ false) when is_list(mac_addresses) do
    case geolocate_from_mac_addresses(mac_addresses, consider_ip) do
      %GeolocationClient.Entities.LatLon{latitude: lat, longitude: lon} = lat_lon ->
        case get_altitude(lat_lon) do
          elevation when is_float(elevation) ->
            %GeolocationClient.Entities.Location{
              latitude: lat,
              longitude: lon,
              altitude: elevation
            }

          {:error, _} = error ->
            error
        end
      {:error, _} = error ->
        error
    end
  end
end