defmodule Microwaveprop.Ionosphere.Observation do
  @moduledoc """
  A single ionosonde measurement for one station at one time. Populated
  from GIRO's DIDBase scaled-characteristic feed and used by the
  propagation scorer for sporadic-E and HF MUF predictions.
  """
  use Ecto.Schema

  import Ecto.Changeset

  @primary_key {:id, :binary_id, autogenerate: true}
  @foreign_key_type :binary_id

  schema "ionosonde_observations" do
    field :station_code, :string
    field :valid_time, :utc_datetime
    field :confidence_score, :integer
    field :fo_f2_mhz, :float
    field :fo_e_mhz, :float
    field :fo_es_mhz, :float
    field :hm_f2_km, :float
    field :mufd_mhz, :float

    timestamps(type: :utc_datetime)
  end

  @type t :: %__MODULE__{}

  @required_fields ~w(station_code valid_time)a
  @optional_fields ~w(confidence_score fo_f2_mhz fo_e_mhz fo_es_mhz hm_f2_km mufd_mhz)a

  @spec changeset(t() | Ecto.Changeset.t(), map()) :: Ecto.Changeset.t()
  def changeset(observation, attrs) do
    observation
    |> cast(attrs, @required_fields ++ @optional_fields)
    |> validate_required(@required_fields)
    |> unique_constraint([:station_code, :valid_time])
  end
end