defmodule ExESDB.Repl do
  @moduledoc """
    This module is to interact with the ExESDB.system, 
    running a store called "reg_gh" (Regulate Greenhouse)
    
  """
  alias ExESDB.Repl.EventGenerator, as: ESGen
  alias ExESDB.Repl.Observer, as: Observer
  alias ExESDB.Repl.Producer, as: Producer
  alias ExESDB.Repl.Subscriber, as: Subscriber

  alias ExESDB.GatewayAPI, as: API

  require Logger

  @store :reg_gh
  @greenhouse1 "greenhouse1"
  @greenhouse2 "greenhouse2"
  @greenhouse3 "greenhouse3"
  @greenhouse4 "greenhouse4"
  @greenhouse5 "greenhouse5"

  @greenhouses [
    @greenhouse1,
    @greenhouse2,
    @greenhouse3,
    @greenhouse4,
    @greenhouse5
  ]

  def store, do: @store
  def stream1, do: @greenhouse1
  def stream2, do: @greenhouse2
  def stream3, do: @greenhouse3
  def stream4, do: @greenhouse4
  def stream5, do: @greenhouse5

  def get_opts, do: ExESDB.Options.app_env()

  def get_streams, do: API.get_streams(@store)

  def get_subscriptions, do: API.get_subscriptions(@store)

  @doc """
    Append events to a stream.
  """
  @spec append(
          stream :: atom(),
          nbr_of_events :: integer()
        ) :: {:ok, list(), integer()} | {:error, term()}
  def append(stream, nbr_of_events) do
    {:ok, version} = API.get_version(@store, stream)

    events = ESGen.generate_events(version, nbr_of_events)

    case @store
         |> API.append_events(stream, events) do
      {:ok, new_version} ->
        {:ok, result} =
          @store
          |> API.get_events(stream, 1, new_version, :forward)

        {:ok, result, result |> Enum.count()}

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

  def start_observer_for_all_streams do
    Logger.warning("Starting Observer for all streams in 5 seconds...
      Switch to :observer application to see it come online.")
    Process.sleep(5_000)
    Observer.start(store: @store, type: :by_stream, selector: "$all")
  end

  def start_observer_for_stream(stream \\ "$greenhouse-1") do
    Logger.warning("Starting Observer for [#{stream}] in 5 seconds...
      Switch to :observer application to see it come online.")
    Process.sleep(5_000)
    Observer.start(store: @store, type: :by_stream, selector: stream)
  end

  @doc """
    Starts an observer for a specific event type.
    ## Possible event types:
    - "initialized:v1" (default)
    - "temperature_measured:v1"
    - "humidity_measured:v1"
    - "light_measured:v1"
    - "fan_activated:v1"
    - "fan_deactivated:v1"
    - "light_activated:v1"
    - "light_deactivated:v1"
    - "heater_activated:v1"
    - "heater_deactivated:v1"
    - "sprinkler_activated:v1"
    - "sprinkler_deactivated:v1"
    - "desired_temperature_set:v1"
    - "desired_humidity_set:v1"
    - "desired_light_set:v1"
  """
  @spec start_observer_for_event_type(event_type :: String.t()) :: :ok
  def start_observer_for_event_type(event_type \\ "initialized:v1") do
    Logger.warning("Starting Observer for [#{event_type}] in 5 seconds...
      Switch to :observer application to see it come online.")
    Process.sleep(5_000)
    Observer.start(store: @store, type: :by_event_type, selector: event_type)
    :ok
  end

  def start_stream_subscriber(name, stream \\ "$greenhouse-1", start_from \\ 0) do
    Logger.warning(
      "Starting Subscriber for [#{name}] to [#{stream}] from [#{start_from}] in 5 seconds... 
      Switch to :observer application to see it come online."
    )

    Process.sleep(5_000)
    Subscriber.start(name, stream, start_from)
  end

  def start_producers(nbr_of_producers \\ 10) do
    Logger.warning("Starting #{nbr_of_producers} Producers in 5 seconds. 
      Switch to :observer application to see them come online.")
    Process.sleep(5_000)

    1..nbr_of_producers
    |> Enum.each(fn n -> Producer.start("greenhouse-#{n}") end)
  end
end