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module Proof = Tezos_context_sigs.Context.Proof_types

(** A container of input data needed to process a consensus. *)
type input = {
  printer : Tezos_client_base.Client_context.printer;
  min_agreement : float;  (** The same value as [Light.sources.min_agreement] *)
  chain : Tezos_shell_services.Block_services.chain;
      (** The chain considered *)
  block : Tezos_shell_services.Block_services.block;
      (** The block considered *)
  key : string list;
      (** The key of the context for which data is being requested *)
  mproof : Proof.tree Proof.t;
      (** The Merkle proof received from the endpoint providing data.
          It is much smaller than the whole context. *)
}

(** [min_agreeing_endpoints min_agreement nb_endpoints] returns
    the minimum number of endpoints that must agree for [Make.consensus]
    to return [true]. The first parameter should be
    [Light.sources.min_agreement] while the second
    parameter should be the length of [Light.sources.endpoints]. *)
val min_agreeing_endpoints : float -> int -> int

(** Given RPCs specific to the light mode, obtain the consensus
    algorithm *)
module Make (Light_proto : Light_proto.PROTO_RPCS) : sig
  (** Whether consensus on data can be achieved. Parameters are:

      - The data to consider
      - The endpoints to contact for validating

      Returns: whether consensus was attained or an error message.
    *)
  val consensus : input -> (Uri.t * Tezos_rpc.Context.simple) list -> bool Lwt.t
end