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(** Options available for the Liquidity Baking per-block vote *)

type liquidity_baking_toggle_vote = LB_on | LB_off | LB_pass

val liquidity_baking_toggle_vote_encoding :
  liquidity_baking_toggle_vote Data_encoding.encoding

(** Exponential moving average of toggle votes. Represented as an int32 between
    0 and 2,000,000. It is an exponential moving average of the [LB_off] votes
    over a window of the most recent 2000 blocks that did not vote [LB_pass]. *)

module Toggle_EMA : sig
  type t

  val of_int32 : Int32.t -> t tzresult Lwt.t

  val zero : t

  val to_int32 : t -> Int32.t

  val encoding : t Data_encoding.t

  val ( < ) : t -> Int32.t -> bool
end

(** [compute_new_ema ~toggle_vote old_ema] returns the value [new_ema] of the
    exponential moving average [old_ema] updated by the vote [toggle_vote].

    It is updated as follows:
    - if [toggle_vote] is [LB_pass] then [new_ema] = [old_ema],
    - if [toggle_vote] is [LB_off], then [new_ema] = (1999 * ema[n] // 2000) + 1,000,000,
    - if [toggle_vote] is [LB_on], then [new_ema] = (1999 * ema[n] // 2000).

    The multiplication is performed in [Z.t] to avoid overflows, division is
    rounded toward 1,000,000,000 (the middle of the interval).
    *)
val compute_new_ema :
  toggle_vote:liquidity_baking_toggle_vote -> Toggle_EMA.t -> Toggle_EMA.t