defmodule ExESDB.Repl.EventGenerator do
  @moduledoc false

  require UUIDv7
  require UUID

  @initialized_v1 "initialized:v1"

  @greenhouse1 "greenhouse1"
  @greenhouse2 "greenhouse2"
  @greenhouse3 "greenhouse3"
  @greenhouse4 "greenhouse4"
  @greenhouse5 "greenhouse5"
  @greenhouse6 "greenhouse6"
  @greenhouse7 "greenhouse7"

  @temperature_measured_v1 "temperature_measured:v1"
  @humidity_measured_v1 "humidity_measured:v1"
  @light_measured_v1 "light_measured:v1"

  @fan_activated_v1 "fan_activated:v1"
  @fan_deactivated_v1 "fan_deactivated:v1"
  @light_activated_v1 "light_activated:v1"
  @light_deactivated_v1 "light_deactivated:v1"
  @heater_activated_v1 "heater_activated:v1"
  @heater_deactivated_v1 "heater_deactivated:v1"
  @sprinkler_activated_v1 "sprinkler_activated:v1"
  @sprinkler_deactivated_v1 "sprinkler_deactivated:v1"

  @desired_temperature_set_v1 "desired_temperature_set:v1"
  @desired_humidity_set_v1 "desired_humidity_set:v1"
  @desired_light_set_v1 "desired_light_set:v1"

  def streams,
    do: [
      @greenhouse1,
      @greenhouse2,
      @greenhouse3,
      @greenhouse4,
      @greenhouse5,
      @greenhouse6,
      @greenhouse7
    ]

  def event_types,
    do: [
      @temperature_measured_v1,
      @humidity_measured_v1,
      @light_measured_v1,
      @desired_temperature_set_v1,
      @desired_humidity_set_v1,
      @desired_light_set_v1,
      @light_activated_v1,
      @light_deactivated_v1,
      @fan_activated_v1,
      @fan_deactivated_v1,
      @heater_activated_v1,
      @heater_deactivated_v1,
      @sprinkler_activated_v1,
      @sprinkler_deactivated_v1
    ]

  @operators [
    "John",
    "Paul",
    "George",
    "Ringo",
    "Jim",
    "Laura",
    "Peter"
  ]

  # Example content type values
  @content_types [1, 2, 3]

  def temperature_measured_v1, do: "temperature_measured:v1"
  def humidity_measured_v1, do: "humidity_measured:v1"
  def light_measured_v1, do: "light_measured:v1"
  def desired_temperature_set_v1, do: "desired_temperature_set:v1"
  def desired_humidity_set_v1, do: "desired_humidity_set:v1"
  def desired_light_set_v1, do: "desired_light_set:v1"
  def light_activated_v1, do: "light_activated:v1"
  def light_deactivated_v1, do: "light_deactivated:v1"
  def fan_activated_v1, do: "fan_activated:v1"
  def fan_deactivated_v1, do: "fan_deactivated:v1"
  def heater_activated_v1, do: "heater_activated:v1"
  def heater_deactivated_v1, do: "heater_deactivated:v1"
  def sprinkler_activated_v1, do: "sprinkler_activated:v1"
  def sprinkler_deactivated_v1, do: "sprinkler_deactivated:v1"

  defp random_operator, do: Enum.random(@operators)
  defp random_temperature, do: 5 + :rand.uniform(30)
  defp random_humidity, do: :rand.uniform(100)
  defp random_light, do: :rand.uniform(100)
  defp random_intensity, do: :rand.uniform(100)

  defp initialized,
    do: %ExESDB.NewEvent{
      event_id: generate_uuid(),
      event_type: @initialized_v1,
      data_content_type: 1,
      metadata_content_type: 1,
      data: %{
        temperature: random_temperature(),
        humidity: random_humidity(),
        light: random_light()
      }
    }

  def generate_events(start_from, count) when is_integer(count) and count > 0 do
    case start_from do
      0 ->
        [initialized() | generate_events(count - 1)]

      _ ->
        generate_events(count)
    end
  end

  def generate_events(0), do: []

  def generate_events(count)
      when is_integer(count) and count > 0,
      do:
        1..count
        |> Enum.map(&generate_event/1)

  defp generate_event(_) do
    event_id = generate_uuid()
    event_type = Enum.random(event_types())

    %ExESDB.NewEvent{
      event_id: event_id,
      event_type: event_type,
      data_content_type: Enum.random(@content_types),
      metadata_content_type: Enum.random(@content_types),
      data: random_payload(event_type),
      metadata: generate_optional_metadata()
    }
  end

  defp generate_uuid, do: UUIDv7.generate()

  defp random_payload(@temperature_measured_v1),
    do: %{
      temperature: random_temperature()
    }

  defp random_payload(@humidity_measured_v1),
    do: %{
      humidity: random_humidity()
    }

  defp random_payload(@light_measured_v1),
    do: %{
      light: random_light()
    }

  defp random_payload(@desired_temperature_set_v1),
    do: %{
      temperature: random_temperature(),
      operator: random_operator()
    }

  defp random_payload(@desired_humidity_set_v1),
    do: %{
      humidity: random_humidity(),
      operator: random_operator()
    }

  defp random_payload(@desired_light_set_v1),
    do: %{
      light: random_light(),
      operator: random_operator()
    }

  defp random_payload(_),
    do: %{
      intensity: random_intensity()
    }

  defp generate_optional_metadata do
    # 70% chance of metadata
    %{
      causation_id: generate_uuid(),
      correlation_id: generate_uuid()
    }
  end
end