/*
    This file is part of TON Blockchain Library.

    TON Blockchain Library is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License as published by
    the Free Software Foundation, either version 2 of the License, or
    (at your option) any later version.

    TON Blockchain Library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with TON Blockchain Library.  If not, see <http://www.gnu.org/licenses/>.

    Copyright 2017-2019 Telegram Systems LLP
*/
#include "apply-block.hpp"
#include "adnl/utils.hpp"
#include "ton/ton-io.hpp"
#include "validator/invariants.hpp"
#include "td/actor/MultiPromise.h"
#include "validator/fabric.h"

namespace ton {

namespace validator {

void ApplyBlock::abort_query(td::Status reason) {
  if (promise_) {
    VLOG(VALIDATOR_WARNING) << "aborting apply block query for " << id_ << ": " << reason;
    promise_.set_error(std::move(reason));
  }
  stop();
}

void ApplyBlock::finish_query() {
  VLOG(VALIDATOR_DEBUG) << "successfully finishing apply block query";
  handle_->set_processed();
  ValidatorInvariants::check_post_apply(handle_);

  if (promise_) {
    promise_.set_value(td::Unit());
  }
  stop();
}

void ApplyBlock::alarm() {
  abort_query(td::Status::Error(ErrorCode::timeout, "timeout"));
}

void ApplyBlock::start_up() {
  VLOG(VALIDATOR_DEBUG) << "running apply_block for " << id_;

  alarm_timestamp() = timeout_;

  auto P = td::PromiseCreator::lambda([SelfId = actor_id(this)](td::Result<BlockHandle> R) {
    if (R.is_error()) {
      td::actor::send_closure(SelfId, &ApplyBlock::abort_query, R.move_as_error());
    } else {
      td::actor::send_closure(SelfId, &ApplyBlock::got_block_handle, R.move_as_ok());
    }
  });

  td::actor::send_closure(manager_, &ValidatorManager::get_block_handle, id_, true, std::move(P));
}

void ApplyBlock::got_block_handle(BlockHandle handle) {
  handle_ = std::move(handle);

  if (handle_->is_applied() && (!handle_->id().is_masterchain() || handle_->processed())) {
    finish_query();
    return;
  }

  if (handle_->is_applied()) {
    auto P =
        td::PromiseCreator::lambda([SelfId = actor_id(this), seqno = handle_->id().id.seqno](td::Result<BlockIdExt> R) {
          R.ensure();
          auto h = R.move_as_ok();
          if (h.id.seqno < seqno) {
            td::actor::send_closure(SelfId, &ApplyBlock::written_block_data);
          } else {
            td::actor::send_closure(SelfId, &ApplyBlock::finish_query);
          }
        });
    td::actor::send_closure(manager_, &ValidatorManager::get_top_masterchain_block, std::move(P));
    return;
  }

  if (handle_->id().id.seqno == 0) {
    written_block_data();
    return;
  }
  if (handle_->id().is_masterchain() && !handle_->inited_proof()) {
    abort_query(td::Status::Error(ErrorCode::notready, "proof is absent"));
    return;
  }
  if (!handle_->id().is_masterchain() && !handle_->inited_proof_link()) {
    abort_query(td::Status::Error(ErrorCode::notready, "proof link is absent"));
    return;
  }

  if (handle_->is_archived()) {
    finish_query();
    return;
  }

  CHECK(handle_->inited_merge_before());
  CHECK(handle_->inited_split_after());
  CHECK(handle_->inited_prev());
  CHECK(handle_->inited_state_root_hash());
  CHECK(handle_->inited_logical_time());

  if (handle_->received()) {
    written_block_data();
    return;
  }

  if (block_.not_null()) {
    auto P = td::PromiseCreator::lambda([SelfId = actor_id(this)](td::Result<td::Unit> R) {
      if (R.is_error()) {
        td::actor::send_closure(SelfId, &ApplyBlock::abort_query, R.move_as_error());
      } else {
        td::actor::send_closure(SelfId, &ApplyBlock::written_block_data);
      }
    });

    td::actor::send_closure(manager_, &ValidatorManager::set_block_data, handle_, block_, std::move(P));
  } else {
    auto P = td::PromiseCreator::lambda([SelfId = actor_id(this), handle = handle_](td::Result<td::Ref<BlockData>> R) {
      CHECK(handle->received());
      if (R.is_error()) {
        td::actor::send_closure(SelfId, &ApplyBlock::abort_query, R.move_as_error());
      } else {
        td::actor::send_closure(SelfId, &ApplyBlock::written_block_data);
      }
    });

    td::actor::send_closure(manager_, &ValidatorManager::wait_block_data, handle_, apply_block_priority(), timeout_,
                            std::move(P));
  }
}

void ApplyBlock::written_block_data() {
  if (handle_->is_applied() && handle_->processed()) {
    finish_query();
  } else {
    auto P = td::PromiseCreator::lambda([SelfId = actor_id(this)](td::Result<td::Ref<ShardState>> R) {
      if (R.is_error()) {
        td::actor::send_closure(SelfId, &ApplyBlock::abort_query, R.move_as_error());
      } else {
        td::actor::send_closure(SelfId, &ApplyBlock::got_cur_state, R.move_as_ok());
      }
    });

    td::actor::send_closure(manager_, &ValidatorManager::wait_block_state, handle_, apply_block_priority(), timeout_,
                            std::move(P));
  }
}

void ApplyBlock::got_cur_state(td::Ref<ShardState> state) {
  state_ = std::move(state);
  CHECK(handle_->received_state());
  written_state();
}

void ApplyBlock::written_state() {
  if (handle_->is_applied() && handle_->processed()) {
    finish_query();
    return;
  }

  if (handle_->id().id.seqno != 0 && !handle_->is_applied()) {
    auto P = td::PromiseCreator::lambda([SelfId = actor_id(this)](td::Result<td::Unit> R) {
      if (R.is_error()) {
        td::actor::send_closure(SelfId, &ApplyBlock::abort_query, R.move_as_error());
      } else {
        td::actor::send_closure(SelfId, &ApplyBlock::written_next);
      }
    });

    td::MultiPromise mp;
    auto g = mp.init_guard();
    g.add_promise(std::move(P));

    td::actor::send_closure(manager_, &ValidatorManager::set_next_block, handle_->one_prev(true), id_, g.get_promise());
    if (handle_->merge_before()) {
      td::actor::send_closure(manager_, &ValidatorManager::set_next_block, handle_->one_prev(false), id_,
                              g.get_promise());
    }
  } else {
    written_next();
  }
}

void ApplyBlock::written_next() {
  if (handle_->is_applied() && handle_->processed()) {
    finish_query();
    return;
  }

  if (handle_->id().id.seqno != 0) {
    auto P = td::PromiseCreator::lambda([SelfId = actor_id(this)](td::Result<td::Unit> R) {
      if (R.is_error()) {
        td::actor::send_closure(SelfId, &ApplyBlock::abort_query, R.move_as_error());
      } else {
        td::actor::send_closure(SelfId, &ApplyBlock::applied_prev);
      }
    });

    td::MultiPromise mp;
    auto g = mp.init_guard();
    g.add_promise(std::move(P));
    run_apply_block_query(handle_->one_prev(true), td::Ref<BlockData>{}, manager_, timeout_, g.get_promise());
    if (handle_->merge_before()) {
      run_apply_block_query(handle_->one_prev(false), td::Ref<BlockData>{}, manager_, timeout_, g.get_promise());
    }
  } else {
    applied_prev();
  }
}

void ApplyBlock::applied_prev() {
  auto P = td::PromiseCreator::lambda([SelfId = actor_id(this)](td::Result<td::Unit> R) {
    if (R.is_error()) {
      td::actor::send_closure(SelfId, &ApplyBlock::abort_query, R.move_as_error());
    } else {
      td::actor::send_closure(SelfId, &ApplyBlock::applied_set);
    }
  });
  td::actor::send_closure(manager_, &ValidatorManager::new_block, handle_, state_, std::move(P));
}

void ApplyBlock::applied_set() {
  handle_->set_applied();
  if (handle_->need_flush()) {
    auto P = td::PromiseCreator::lambda([SelfId = actor_id(this)](td::Result<td::Unit> R) {
      if (R.is_error()) {
        td::actor::send_closure(SelfId, &ApplyBlock::abort_query, R.move_as_error());
      } else {
        td::actor::send_closure(SelfId, &ApplyBlock::finish_query);
      }
    });
    handle_->flush(manager_, handle_, std::move(P));
  } else {
    finish_query();
  }
}

}  // namespace validator

}  // namespace ton