// Copyright 2015 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Author: cheesy@google.com (Steve Hill)

#include "net/instaweb/rewriter/public/compatible_central_controller.h"

#include "pagespeed/kernel/util/statistics_work_bound.h"

namespace net_instaweb {

const char CompatibleCentralController::kCurrentExpensiveOperations[] =
    "current-expensive-operations";

CompatibleCentralController::CompatibleCentralController(
    int max_expensive_operations, Statistics* statistics)
    : work_bound_(new StatisticsWorkBound(
          statistics->GetUpDownCounter(kCurrentExpensiveOperations),
          max_expensive_operations)) {}

CompatibleCentralController::~CompatibleCentralController() {
}

void CompatibleCentralController::InitStats(Statistics* statistics) {
  statistics->AddGlobalUpDownCounter(kCurrentExpensiveOperations);
}

void CompatibleCentralController::ScheduleExpensiveOperation(
    Function* callback) {
  if (work_bound_->TryToWork()) {
    callback->CallRun();
  } else {
    callback->CallCancel();
  }
}

void CompatibleCentralController::NotifyExpensiveOperationComplete() {
  work_bound_->WorkComplete();
}

}  // namespace net_instaweb