/*
 * Strawberry Music Player
 * This file was part of Clementine.
 * Copyright 2010, David Sansome <me@davidsansome.com>
 *
 * Strawberry is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Strawberry 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
 * 
 */

#include "config.h"

#include "network.h"

#include <QCoreApplication>
#include <QStandardPaths>
#include <QDir>
#include <QNetworkAccessManager>
#include <QNetworkDiskCache>
#include <QNetworkReply>

#include "core/closure.h"
#include "core/logging.h"

QMutex ThreadSafeNetworkDiskCache::sMutex;
QNetworkDiskCache *ThreadSafeNetworkDiskCache::sCache = nullptr;

ThreadSafeNetworkDiskCache::ThreadSafeNetworkDiskCache(QObject *parent)
: QAbstractNetworkCache(parent) {
  QMutexLocker l(&sMutex);
  if (!sCache) {
    sCache = new QNetworkDiskCache;
#ifdef Q_OS_WIN32
    sCache->setCacheDirectory(QStandardPaths::writableLocation(QStandardPaths::TempLocation) + "/strawberry/networkcache");
#else
    sCache->setCacheDirectory(QStandardPaths::writableLocation(QStandardPaths::CacheLocation) + "/networkcache");
#endif
  }
}

qint64 ThreadSafeNetworkDiskCache::cacheSize() const {
  QMutexLocker l(&sMutex);
  return sCache->cacheSize();
}

QIODevice *ThreadSafeNetworkDiskCache::data(const QUrl &url) {
  QMutexLocker l(&sMutex);
  return sCache->data(url);
}

void ThreadSafeNetworkDiskCache::insert(QIODevice *device) {
  QMutexLocker l(&sMutex);
  sCache->insert(device);
}

QNetworkCacheMetaData ThreadSafeNetworkDiskCache::metaData(const QUrl &url) {
  QMutexLocker l(&sMutex);
  return sCache->metaData(url);
}

QIODevice *ThreadSafeNetworkDiskCache::prepare(const QNetworkCacheMetaData &metaData) {
  QMutexLocker l(&sMutex);
  return sCache->prepare(metaData);
}

bool ThreadSafeNetworkDiskCache::remove(const QUrl &url) {
  QMutexLocker l(&sMutex);
  return sCache->remove(url);
}

void ThreadSafeNetworkDiskCache::updateMetaData(const QNetworkCacheMetaData &metaData) {
  QMutexLocker l(&sMutex);
  sCache->updateMetaData(metaData);
}

void ThreadSafeNetworkDiskCache::clear() {
  QMutexLocker l(&sMutex);
  sCache->clear();
}

NetworkAccessManager::NetworkAccessManager(QObject *parent)
    : QNetworkAccessManager(parent) {
  setCache(new ThreadSafeNetworkDiskCache(this));
}

QNetworkReply *NetworkAccessManager::createRequest(Operation op, const QNetworkRequest &request, QIODevice *outgoingData) {

  QByteArray user_agent = QString("%1 %2").arg(QCoreApplication::applicationName(), QCoreApplication::applicationVersion()).toUtf8();

  if (request.hasRawHeader("User-Agent")) {
    // Append the existing user-agent set by a client collection (such as libmygpo-qt).
    user_agent += " " + request.rawHeader("User-Agent");
  }

  QNetworkRequest new_request(request);
  new_request.setRawHeader("User-Agent", user_agent);

  if (op == QNetworkAccessManager::PostOperation && !new_request.header(QNetworkRequest::ContentTypeHeader).isValid()) {
    new_request.setHeader(QNetworkRequest::ContentTypeHeader, "application/x-www-form-urlencoded");
  }

  // Prefer the cache unless the caller has changed the setting already
  if (request.attribute(QNetworkRequest::CacheLoadControlAttribute).toInt() == QNetworkRequest::PreferNetwork) {
    new_request.setAttribute(QNetworkRequest::CacheLoadControlAttribute, QNetworkRequest::PreferCache);
  }

  return QNetworkAccessManager::createRequest(op, new_request, outgoingData);
}


NetworkTimeouts::NetworkTimeouts(int timeout_msec, QObject *parent)
    : QObject(parent), timeout_msec_(timeout_msec) {}

void NetworkTimeouts::AddReply(QNetworkReply *reply) {

  if (timers_.contains(reply)) return;

  connect(reply, SIGNAL(destroyed()), SLOT(ReplyFinished()));
  connect(reply, SIGNAL(finished()), SLOT(ReplyFinished()));
  timers_[reply] = startTimer(timeout_msec_);

}

void NetworkTimeouts::AddReply(RedirectFollower *reply) {

  if (redirect_timers_.contains(reply)) {
    return;
  }

  NewClosure(reply, SIGNAL(destroyed()), this, SLOT(RedirectFinished(RedirectFollower*)), reply);
  NewClosure(reply, SIGNAL(finished()), this, SLOT(RedirectFinished(RedirectFollower*)), reply);
  redirect_timers_[reply] = startTimer(timeout_msec_);

}

void NetworkTimeouts::ReplyFinished() {

  QNetworkReply *reply = reinterpret_cast<QNetworkReply*>(sender());
  if (timers_.contains(reply)) {
    killTimer(timers_.take(reply));
  }

}

void NetworkTimeouts::RedirectFinished(RedirectFollower *reply) {

  if (redirect_timers_.contains(reply)) {
    killTimer(redirect_timers_.take(reply));
  }

}

void NetworkTimeouts::timerEvent(QTimerEvent *e) {

  QNetworkReply *reply = timers_.key(e->timerId());
  if (reply) {
    reply->abort();
  }

  RedirectFollower *redirect = redirect_timers_.key(e->timerId());
  if (redirect) {
    redirect->abort();
  }

}


RedirectFollower::RedirectFollower(QNetworkReply *first_reply, int max_redirects) : QObject(nullptr), current_reply_(first_reply), redirects_remaining_(max_redirects) {
  ConnectReply(first_reply);
}

void RedirectFollower::ConnectReply(QNetworkReply *reply) {

  connect(reply, SIGNAL(readyRead()), SLOT(ReadyRead()));
  connect(reply, SIGNAL(error(QNetworkReply::NetworkError)), SIGNAL(error(QNetworkReply::NetworkError)));
  connect(reply, SIGNAL(downloadProgress(qint64,qint64)), SIGNAL(downloadProgress(qint64,qint64)));
  connect(reply, SIGNAL(uploadProgress(qint64,qint64)), SIGNAL(uploadProgress(qint64,qint64)));
  connect(reply, SIGNAL(finished()), SLOT(ReplyFinished()));

}

void RedirectFollower::ReadyRead() {

  // Don't re-emit this signal for redirect replies.
  if (current_reply_->attribute(QNetworkRequest::RedirectionTargetAttribute).isValid()) {
    return;
  }

  emit readyRead();

}

void RedirectFollower::ReplyFinished() {

  current_reply_->deleteLater();

  if (current_reply_->attribute(QNetworkRequest::RedirectionTargetAttribute).isValid()) {
    if (redirects_remaining_-- == 0) {
      emit finished();
      return;
    }

    const QUrl next_url = current_reply_->url().resolved(current_reply_->attribute(QNetworkRequest::RedirectionTargetAttribute).toUrl());

    QNetworkRequest req(current_reply_->request());
    req.setUrl(next_url);

    current_reply_ = current_reply_->manager()->get(req);
    ConnectReply(current_reply_);
    return;
  }

  emit finished();

}