(*****************************************************************************)
(*                                                                           *)
(* Open Source License                                                       *)
(* Copyright (c) 2018 Dynamic Ledger Solutions, Inc. <contact@tezos.com>     *)
(*                                                                           *)
(* Permission is hereby granted, free of charge, to any person obtaining a   *)
(* copy of this software and associated documentation files (the "Software"),*)
(* to deal in the Software without restriction, including without limitation *)
(* the rights to use, copy, modify, merge, publish, distribute, sublicense,  *)
(* and/or sell copies of the Software, and to permit persons to whom the     *)
(* Software is furnished to do so, subject to the following conditions:      *)
(*                                                                           *)
(* The above copyright notice and this permission notice shall be included   *)
(* in all copies or substantial portions of the Software.                    *)
(*                                                                           *)
(* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR*)
(* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,  *)
(* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL   *)
(* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER*)
(* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING   *)
(* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER       *)
(* DEALINGS IN THE SOFTWARE.                                                 *)
(*                                                                           *)
(*****************************************************************************)

open Alpha_context

type rpc_context = {
  block_hash: Block_hash.t ;
  block_header: Block_header.shell_header ;
  context: Alpha_context.t ;
}

let rpc_init ({ block_hash ; block_header ; context } : Updater.rpc_context) =
  let level = block_header.level in
  let timestamp = block_header.timestamp in
  let fitness = block_header.fitness in
  Alpha_context.prepare ~level ~timestamp ~fitness context >>=? fun context ->
  return { block_hash ; block_header ; context }

let rpc_services = ref (RPC_directory.empty : Updater.rpc_context RPC_directory.t)

let register0_fullctxt s f =
  rpc_services :=
    RPC_directory.register !rpc_services s
      (fun ctxt q i ->
         rpc_init ctxt >>=? fun ctxt ->
         f ctxt q i)
let opt_register0_fullctxt s f =
  rpc_services :=
    RPC_directory.opt_register !rpc_services s
      (fun ctxt q i ->
         rpc_init ctxt >>=? fun ctxt ->
         f ctxt q i)
let register0 s f =
  register0_fullctxt s (fun { context ; _ } -> f context)
let register0_noctxt s f =
  rpc_services :=
    RPC_directory.register !rpc_services s
      (fun _ q i -> f q i)

let register1_fullctxt s f =
  rpc_services :=
    RPC_directory.register !rpc_services s
      (fun (ctxt, arg) q i ->
         rpc_init ctxt >>=? fun ctxt ->
         f ctxt arg q i)
let register1 s f = register1_fullctxt s (fun { context ; _ } x -> f context x)
let register1_noctxt s f =
  rpc_services :=
    RPC_directory.register !rpc_services s
      (fun (_, arg) q i -> f arg q i)

let register2_fullctxt s f =
  rpc_services :=
    RPC_directory.register !rpc_services s
      (fun ((ctxt, arg1), arg2) q i ->
         rpc_init ctxt >>=? fun ctxt ->
         f ctxt arg1 arg2 q i)
let register2 s f =
  register2_fullctxt s (fun { context ; _ } a1 a2 q i -> f context a1 a2 q i)

let get_rpc_services () =
  let p =
    RPC_directory.map
      (fun c ->
         rpc_init c >>= function
         | Error _ -> assert false
         | Ok c -> Lwt.return c.context)
      (Storage_description.build_directory Alpha_context.description) in
  RPC_directory.register_dynamic_directory
    !rpc_services
    RPC_path.(open_root / "context" / "raw" / "json")
    (fun _ -> Lwt.return p)