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exception Status_already_ready

let store_path_prefix = "store"

type dac_plugin_module = (module Dac_plugin.T)

module Coordinator = struct
  type t = {
    committee_members : Wallet_account.Coordinator.t list;
    hash_streamer : Dac_plugin.raw_hash Data_streamer.t;
    certificate_streamers : Certificate_streamers.t;
  }

  let get_all_committee_members_public_keys committee_members_public_keys =
    List.map_es
      Wallet_account.Coordinator.of_committee_member_public_key
      committee_members_public_keys

  let init coordinator_config =
    let open Lwt_result_syntax in
    let Configuration.Coordinator.{committee_members; _} = coordinator_config in
    let+ committee_members =
      get_all_committee_members_public_keys committee_members
    in
    let hash_streamer = Data_streamer.init () in
    let certificate_streamers = Certificate_streamers.init () in
    {committee_members; hash_streamer; certificate_streamers}

  let public_keys_opt t =
    List.map
      (fun Wallet_account.Coordinator.{public_key; _} -> Some public_key)
      t.committee_members

  let committee_members t =
    List.map
      (fun Wallet_account.Coordinator.{public_key_hash; _} -> public_key_hash)
      t.committee_members
end

module Committee_member = struct
  type t = {
    committee_member : Wallet_account.Committee_member.t;
    coordinator_cctxt : Dac_node_client.cctxt;
  }

  let init committee_member_config cctxt =
    let open Lwt_result_syntax in
    let Configuration.Committee_member.{address; coordinator_rpc_address} =
      committee_member_config
    in
    let+ committee_member =
      Wallet_account.Committee_member.of_committee_member_address address cctxt
    in
    let coordinator_cctxt = Dac_node_client.of_uri coordinator_rpc_address in
    {committee_member; coordinator_cctxt}

  let secret_key_uri t =
    let Wallet_account.Committee_member.{secret_key_uri; _} =
      t.committee_member
    in
    secret_key_uri
end

module Observer = struct
  type t = {
    coordinator_cctxt : Dac_node_client.cctxt;
    committee_cctxts : Dac_node_client.cctxt list;
    timeout : int;
  }

  let init observer_config =
    let open Lwt_result_syntax in
    let Configuration.Observer.
          {coordinator_rpc_address; committee_rpc_addresses; timeout} =
      observer_config
    in
    let coordinator_cctxt = Dac_node_client.of_uri coordinator_rpc_address in
    let committee_cctxts =
      List.map Dac_node_client.of_uri committee_rpc_addresses
    in
    return {coordinator_cctxt; committee_cctxts; timeout}
end

type mode =
  | Coordinator of Coordinator.t
  | Committee_member of Committee_member.t
  | Observer of Observer.t

type ready_ctxt = {dac_plugin : dac_plugin_module}

type status = Ready of ready_ctxt | Starting

type t = {
  mutable status : status;
  reveal_data_dir : string;
  tezos_node_cctxt : Client_context.full;
  page_store : Page_store.Filesystem.t;
  node_store : Store_sigs.rw Store.Irmin_store.t;
  mode : mode;
}

let init_mode Configuration.{mode; _} cctxt =
  let open Lwt_result_syntax in
  match mode with
  | Coordinator config ->
      let+ mode_node_ctxt = Coordinator.init config in
      Coordinator mode_node_ctxt
  | Committee_member config ->
      let+ mode_node_ctxt = Committee_member.init config cctxt in
      Committee_member mode_node_ctxt
  | Observer config ->
      let+ mode_node_ctxt = Observer.init config in
      Observer mode_node_ctxt

let init config cctxt =
  let open Lwt_result_syntax in
  let* node_store =
    Store.Irmin_store.load
      Store_sigs.Read_write
      (Configuration.data_dir_path config store_path_prefix)
  in
  let+ mode = init_mode config cctxt in
  {
    status = Starting;
    reveal_data_dir = Configuration.reveal_data_dir config;
    tezos_node_cctxt = cctxt;
    page_store =
      Page_store.Filesystem.init (Configuration.reveal_data_dir config);
    node_store;
    mode;
  }

let get_mode node_ctxt = node_ctxt.mode

let set_ready ctxt dac_plugin =
  match ctxt.status with
  | Starting ->
      (* FIXME: https://gitlab.com/tezos/tezos/-/issues/4681
         Currently, Dac only supports coordinator functionalities but we might
         want to filter this capability out depending on the profile.
      *)
      ctxt.status <- Ready {dac_plugin}
  | Ready _ -> raise Status_already_ready

type error += Node_not_ready

let () =
  register_error_kind
    `Permanent
    ~id:"dac.node.not.ready"
    ~title:"DAC Node not ready"
    ~description:"DAC node is starting. It's not ready to respond to RPCs."
    ~pp:(fun ppf () ->
      Format.fprintf
        ppf
        "DAC node is starting. It's not ready to respond to RPCs.")
    Data_encoding.(unit)
    (function Node_not_ready -> Some () | _ -> None)
    (fun () -> Node_not_ready)

let get_ready ctxt =
  let open Result_syntax in
  match ctxt.status with
  | Ready ctxt -> Ok ctxt
  | Starting -> fail [Node_not_ready]

let get_status ctxt = ctxt.status

let get_tezos_node_cctxt ctxt = ctxt.tezos_node_cctxt

let get_dac_plugin ctxt =
  let open Result_syntax in
  match ctxt.status with
  | Ready {dac_plugin} -> Ok dac_plugin
  | Starting -> tzfail Node_not_ready

let get_page_store ctxt = ctxt.page_store

let get_node_store (type a) ctxt (access_mode : a Store_sigs.mode) :
    a Store.Irmin_store.t =
  match access_mode with
  | Store_sigs.Read_only -> Store.Irmin_store.readonly ctxt.node_store
  | Store_sigs.Read_write -> ctxt.node_store