(**************************************************************************)
(*                                                                        *)
(*    Copyright (c) 2014 - 2018.                                          *)
(*    Dynamic Ledger Solutions, Inc. <contact@tezos.com>                  *)
(*                                                                        *)
(*    All rights reserved. No warranty, explicit or implicit, provided.   *)
(*                                                                        *)
(**************************************************************************)

open Proto_alpha
open Alpha_context

module Main = Alpha_environment.Lift(Main)

type incremental = {
  predecessor: Client_baking_blocks.block_info ;
  context : Context.t ;
  state: Main.validation_state ;
  rev_operations: Operation.packed list ;
  header: Tezos_base.Block_header.shell_header ;
}

let load_context ~context_path =
  Context.init ~readonly:true context_path

let begin_construction (_cctxt : #Proto_alpha.full) index predecessor =
  let { Client_baking_blocks.context } = predecessor in
  Context.checkout_exn index context >>= fun context ->
  let timestamp = Time.now () in
  let predecessor_hash = predecessor.hash in
  (* Shell_services.Blocks.header cctxt ~chain:`Main ~block:(`Hash (predecessor_hash, 0)) ()
   * >>=? fun { shell ; _ } -> *)
  let header : Tezos_base.Block_header.shell_header = Tezos_base.Block_header.{
      predecessor = predecessor_hash ;
      proto_level = 0 (* shell.proto_level *) ;
      validation_passes = 0 (* shell.validation_passes *) ;
      fitness = predecessor.fitness (* shell.fitness *) ;
      timestamp ;
      level = 0l (* shell.level *) ;
      context = Context_hash.zero ;
      operations_hash = Operation_list_list_hash.zero ;
    } in
  Main.begin_construction
    ~predecessor_context: context
    ~predecessor_timestamp: header.timestamp
    ~predecessor_fitness: header.fitness
    ~predecessor_level: header.level
    ~predecessor:predecessor_hash
    ~timestamp
    () >>=? fun state ->
  return {
    predecessor ;
    context ;
    state ;
    rev_operations = [] ;
    header ;
  }

let add_operation st ( op : Operation.packed ) =
  Main.apply_operation st.state op >>=? fun (state, _) ->
  return { st with state ; rev_operations = op :: st.rev_operations }

let finalize_construction inc =
  Main.finalize_block inc.state >>=? fun _ -> return ()