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(* Open Source License                                                       *)
(* Copyright (c) 2018 Dynamic Ledger Solutions, Inc. <contact@tezos.com>     *)
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(** All the (persistent) metadata associated to a peer. *)

type t

val encoding : t Data_encoding.t

val empty : unit -> t

(** the aggregate score function computed from
    the metadata collected for a peer *)
val distributed_db_score : t -> float

val prevalidation_score : t -> float

val score : t -> float

type requests_kind =
  | Branch
  | Head
  | Block_header
  | Operations
  | Protocols
  | Operation_hashes_for_block
  | Operations_for_block
  | Checkpoint
  | Protocol_branch
  | Predecessor_header
  | Other

type resource_kind = Block | Operations | Protocol

type advertisement = Head | Branch

type metadata =
  (* Distributed_db *)
  | Received_request of requests_kind
  | Sent_request of requests_kind
  | Failed_request of requests_kind
  | Scheduled_request of requests_kind
  | Received_response of requests_kind
  | Sent_response of requests_kind
  | Unexpected_response
  | Unactivated_chain
  | Inactive_chain
  | Future_block
  | Unadvertised of resource_kind
  | Sent_advertisement of advertisement
  | Received_advertisement of advertisement
  | Outdated_response (* TODO : unused *)
  (* Peer validator *)
  | Valid_blocks
  | Old_heads
  (* Prevalidation *)
  | Cannot_download
  | Cannot_parse
  | Refused_by_prefilter
  | Refused_by_postfilter
  | Applied
  | Branch_delayed
  | Branch_refused
  | Refused
  | Duplicate
  | Outdated

(** incr score counters . Used to compute the final score for a peer *)
val incr : t -> metadata -> unit

val update_requests : t -> requests_kind -> bool -> unit

val update_responses : t -> requests_kind -> bool -> unit