defmodule Polymarket.Schemas.MarketByToken do
  @moduledoc """
  The parent market for a given token ID, as returned by the CLOB API
  `GET /markets-by-token/:token_id`.

  Resolves a token ID to its market's `condition_id` and both the primary (Yes)
  and secondary (No) token IDs. The CLOB API already delivers `snake_case` keys,
  so `from_attrs/1` normalisation is a no-op here but kept for consistency with
  the other schemas.
  """

  use TypedEctoSchema

  alias Polymarket.JsonUtil
  alias Polymarket.Schemas.Coerce

  @primary_key false

  @derive Jason.Encoder
  typed_embedded_schema do
    field(:condition_id, :string)
    field(:primary_token_id, :string)
    field(:secondary_token_id, :string)
  end

  @required [:condition_id, :primary_token_id, :secondary_token_id]

  @doc """
  Builds a `MarketByToken` from the raw (JSON-decoded) CLOB attributes. Keys may
  be in `camelCase` (atom or string); they are normalised to the `snake_case`
  fields. Returns `{:error, {:missing_fields, fields}}` when a required field is
  absent.
  """
  @spec from_attrs(map()) :: {:ok, t()} | {:error, {:missing_fields, [atom()]}}
  def from_attrs(attrs) do
    attrs = JsonUtil.snake_case_keys(attrs)

    %__MODULE__{
      condition_id: attrs["condition_id"],
      primary_token_id: attrs["primary_token_id"],
      secondary_token_id: attrs["secondary_token_id"]
    }
    |> Coerce.require_fields(@required)
  end
end