Source file per_block_votes_repr.ml

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(** Options available for per-block votes *)

type per_block_vote =
  | Per_block_vote_on
  | Per_block_vote_off
  | Per_block_vote_pass

type per_block_votes = {
  liquidity_baking_vote : per_block_vote;
  adaptive_issuance_vote : per_block_vote;
}

let ema_max = 2_000_000_000l

let per_block_vote_compact_encoding =
  let open Data_encoding in
  let open Compact in
  union
    ~union_tag_bits:2
    ~cases_tag_bits:0
    [
      case
        ~title:"per_block_vote_on"
        (payload (constant "on"))
        (function Per_block_vote_on -> Some () | _ -> None)
        (fun () -> Per_block_vote_on);
      case
        ~title:"per_block_vote_off"
        (payload (constant "off"))
        (function Per_block_vote_off -> Some () | _ -> None)
        (fun () -> Per_block_vote_off);
      case
        ~title:"per_block_vote_pass"
        (payload (constant "pass"))
        (function Per_block_vote_pass -> Some () | _ -> None)
        (fun () -> Per_block_vote_pass);
    ]

let liquidity_baking_vote_encoding =
  let open Data_encoding in
  def
    "liquidity_baking_vote"
    (Compact.make ~tag_size:`Uint8 per_block_vote_compact_encoding)

let adaptive_issuance_vote_encoding =
  let open Data_encoding in
  def
    "adaptive_issuance_vote"
    (Compact.make ~tag_size:`Uint8 per_block_vote_compact_encoding)

let per_block_votes_compact_encoding =
  let open Data_encoding in
  let open Compact in
  conv
    (fun {liquidity_baking_vote; adaptive_issuance_vote} ->
      (liquidity_baking_vote, adaptive_issuance_vote))
    (fun (liquidity_baking_vote, adaptive_issuance_vote) ->
      {liquidity_baking_vote; adaptive_issuance_vote})
    (obj2
       (req "liquidity_baking_vote" per_block_vote_compact_encoding)
       (req "adaptive_issuance_vote" per_block_vote_compact_encoding))

let per_block_votes_encoding =
  let open Data_encoding in
  def
    "per_block_votes"
    (Compact.make ~tag_size:`Uint8 per_block_votes_compact_encoding)

module Liquidity_baking_toggle_EMA = Votes_EMA_repr.Make (struct
  let baker_contribution = Z.of_int 500_000

  let ema_max = ema_max
end)

module Adaptive_issuance_launch_EMA = Votes_EMA_repr.Make (struct
  (* The baker_contribution parameter of the adaptive issuance
     activation vote was chosen so that 2 weeks are needed to move
     the EMA from 0% to 50% when all bakers vote On.

     This was computed using the following formula:

     baker_contrib = (1/2) * ema_max * (1 - 2^(-1/k))

     where k is the number of blocks in 2 weeks (which is 120960).

     Because of a small accumulation of rounding errors, two more
     blocks are actually needed. *)
  let baker_contribution = Z.of_int 5730

  let ema_max = ema_max
end)

let compute_new_liquidity_baking_ema ~per_block_vote ema =
  match per_block_vote with
  | Per_block_vote_pass -> ema
  | Per_block_vote_off -> Liquidity_baking_toggle_EMA.update_ema_up ema
  | Per_block_vote_on -> Liquidity_baking_toggle_EMA.update_ema_down ema

let compute_new_adaptive_issuance_ema ~per_block_vote ema =
  match per_block_vote with
  | Per_block_vote_pass -> ema
  | Per_block_vote_off -> Adaptive_issuance_launch_EMA.update_ema_down ema
  | Per_block_vote_on -> Adaptive_issuance_launch_EMA.update_ema_up ema

module Internal_for_tests = struct
  let ema_max = ema_max
end