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(**
   Amendments and proposals.

   Only delegates having the minimal required stake take part in the amendment
   procedure.  It works as follows:

   - Proposal period: delegates can submit protocol amendment
   proposals using the proposal operation. At the end of a proposal
   period, the proposal with most supporters is selected and we move
   to an exploration period. If there are no proposals, or a tie
   between proposals, a new proposal period starts.

   - Exploration period: delegates can cast votes to test or not the
   winning proposal using the ballot operation.  At the end of an
   exploration period if participation reaches the quorum and the
   proposal has a supermajority in favor, we proceed to a cooldown
   period. Otherwise we go back to a proposal period.  In any case, if
   there is enough participation the quorum is updated.

   - Cooldown period: business as usual for the main chain. This
   period is only a time gap between exploration and promotion
   periods intended to provide the community with extra time to
   continue testing the new protocol proposal, and start adapting
   their infrastructure in advance.  At the end of the Cooldown
   period we move to the Promotion period.

   - Promotion period: delegates can cast votes to promote or not the
   proposal using the ballot operation.  At the end of a promotion
   period if participation reaches the quorum and the proposal has a
   supermajority in favor, we move to an adoption period. Otherwise we
   go back to a proposal period.  In any case, if there is enough
   participation the quorum is updated.

   - Adoption period: At the end of an adoption period, the proposal
   is activated as the new protocol.

   The current protocol parameters are documented in
   src/proto_alpha/lib_parameters/default_parameters.ml

   In practice, the real constants used are defined in the
   migration code. In src/proto_alpha/lib_protocol/init_storage.ml,
   function [prepare_first_block] introduces new constants and
   redefines the existing ones.
*)

open Alpha_context

(** If at the end of a voting period, moves to the next one following
    the state machine of the amendment procedure. *)
val may_start_new_voting_period : context -> context tzresult Lwt.t

(** Return the registered testchain dictator, if any. This function will always
    return None on mainnet. *)
val get_testnet_dictator : context -> Chain_id.t -> public_key_hash option

(** Check whether the given public key hash corresponds to the
    registered testchain dictator, if any. This function will always
    return false on mainnet. *)
val is_testnet_dictator : context -> Chain_id.t -> public_key_hash -> bool

(** {2 Application of voting operations}

    There are two kinds of voting operations:

    - Proposals: A delegate submits a list of protocol amendment
      proposals. This operation is only accepted during a Proposal period
      (see above).

    - Ballot: A delegate casts a vote for/against the current proposal
      (or pass). This operation is only accepted during an Exploration
      or Promotion period (see above). *)

(** Update the [context] with the effects of a Proposals operation:

    - Its proposals are added to the source's recorded proposals.

    - The recorded proposal count of the source is increased by the
      number of proposals in the operation.

    Note that a Proposals operation from a testnet dictator (which may
    be set up when a test chain is initialized) has completely
    different effects:

    - If the operation contains no proposal, then the current voting
      period is immediately and forcibly set to a Proposal period.

    - If the operation contains exactly one proposal, then the current
      voting period is immediately and forcibly set to an Adoption period
      for this proposal.

    {!validate_proposals} must have been called beforehand, and is
    responsible for ensuring that [apply_proposals] cannot fail. *)
val apply_proposals :
  context ->
  Chain_id.t ->
  Kind.proposals contents ->
  (context * Kind.proposals Apply_results.contents_result_list) tzresult Lwt.t

(** Update the [context] with the effects of a Ballot operation:

    The couple (source of the operation, submitted ballot) is recorded.

    {!validate_ballot} must have been called beforehand, and is
    responsible for ensuring that [apply_ballot] cannot fail. *)
val apply_ballot :
  context ->
  Kind.ballot contents ->
  (context * Kind.ballot Apply_results.contents_result_list) tzresult Lwt.t