// Copyright (c) 2012-2015, The CryptoNote developers, The Bytecoin developers
//
// This file is part of Bytecoin.
//
// Bytecoin 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 3 of the License, or
// (at your option) any later version.
//
// Bytecoin 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 Bytecoin.  If not, see <http://www.gnu.org/licenses/>.

#include "Timer.h"
#include <cassert>
#include <string>
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#include <System/InterruptedException.h>
#include "Dispatcher.h"

namespace System {

namespace {

struct TimerContext {
  uint64_t time;
  void* context;
  bool interrupted;
};

}

Timer::Timer() : dispatcher(nullptr) {
}

Timer::Timer(Dispatcher& dispatcher) : dispatcher(&dispatcher), stopped(false), context(nullptr) {
}

Timer::Timer(Timer&& other) : dispatcher(other.dispatcher) {
  if (dispatcher != nullptr) {
    assert(other.context == nullptr);
    stopped = other.stopped;
    context = nullptr;
    other.dispatcher = nullptr;
  }
}

Timer::~Timer() {
  assert(dispatcher == nullptr || context == nullptr);
}

Timer& Timer::operator=(Timer&& other) {
  assert(dispatcher == nullptr || context == nullptr);
  dispatcher = other.dispatcher;
  if (dispatcher != nullptr) {
    assert(other.context == nullptr);
    stopped = other.stopped;
    context = nullptr;
    other.dispatcher = nullptr;
  }

  return *this;
}

void Timer::start() {
  assert(dispatcher != nullptr);
  assert(stopped);
  stopped = false;
}

void Timer::stop() {
  assert(dispatcher != nullptr);
  assert(!stopped);
  if (context != nullptr) {
    TimerContext* timerContext = static_cast<TimerContext*>(context);
    if (!timerContext->interrupted) {
      dispatcher->interruptTimer(timerContext->time, timerContext->context);
      timerContext->interrupted = true;
    }
  }

  stopped = true;
}

void Timer::sleep(std::chrono::nanoseconds duration) {
  assert(dispatcher != nullptr);
  assert(context == nullptr);
  if (stopped) {
    throw InterruptedException();
  }

  LARGE_INTEGER frequency;
  LARGE_INTEGER ticks;
  QueryPerformanceCounter(&ticks);
  QueryPerformanceFrequency(&frequency);
  uint64_t currentTime = ticks.QuadPart / (frequency.QuadPart / 1000);
  uint64_t time = currentTime + duration.count() / 1000000;
  void* fiber = GetCurrentFiber();
  TimerContext timerContext{ time, fiber, false };
  context = &timerContext;
  dispatcher->addTimer(time, fiber);
  dispatcher->dispatch();
  assert(timerContext.context == GetCurrentFiber());
  assert(dispatcher != nullptr);
  assert(context == &timerContext);
  context = nullptr;
  if (timerContext.interrupted) {
    throw InterruptedException();
  }
}

}