#include <QWebView>
#include <QWebFrame>
#include <QWebElement>
#include <QSettings>
#include <QNetworkReply>
#include <QTimer>

#include "GoogleWebTranslator.h"
#include "Settings.h"
#include "StAssert.h"

GoogleWebTranslator::GoogleWebTranslator()
  : QObject (), view_ (new QWebView),
    isLoadFinished_ (true), isTranslationFinished_ (false) {

  view_->settings()->setAttribute(QWebSettings::AutoLoadImages, false);
  connect (view_, SIGNAL (loadStarted()), this, SLOT (loadStarted()));
  connect (view_, SIGNAL (loadFinished(bool)), this, SLOT (loadFinished(bool)));

  connect (view_->page()->networkAccessManager(), SIGNAL (finished(QNetworkReply*)),
           this, SLOT(replyFinished(QNetworkReply*)));
  applySettings ();
}

GoogleWebTranslator::~GoogleWebTranslator() {
  delete view_;
}

void GoogleWebTranslator::translate(ProcessingItem item) {
  queue_.push_back (item);
  if (isLoadFinished_) {
    load (item);
  }
}

void GoogleWebTranslator::applySettings(){
  QSettings settings;
  settings.beginGroup (settings_names::translationGroup);
  translationLanguage_ = settings.value (settings_names::translationLanguage,
                                         settings_values::translationLanguage).toString ();
}

void GoogleWebTranslator::loadStarted() {
  isLoadFinished_ = false;
  isTranslationFinished_ = false;
}

void GoogleWebTranslator::loadFinished(bool ok) {
  isLoadFinished_ = true;
  if (ok && !isTranslationFinished_) {
      return;
  }

  if (!queue_.isEmpty()) {
    ProcessingItem item = queue_.front();
    queue_.pop_front();
    if (ok) {
      QWebElementCollection result = view_->page()->mainFrame()->findAllElements("#result_box > span");
      item.translated = "";
      foreach (const QWebElement& element, result) {
        item.translated += element.toInnerXml() + " ";
      }
      emit translated(item, !item.translated.isEmpty());
    }
    else {
      emit translated (item, false);
    }
  }

  if (!queue_.isEmpty()) {
    load (queue_.front());
  }
}

void GoogleWebTranslator::replyFinished(QNetworkReply *reply)
{
  if (reply->url().toString().contains ("/translate_a/single")) {
    isTranslationFinished_ = true;
    if (isLoadFinished_) {
      QTimer::singleShot(2000, this, SLOT(loadFinished()));
    }
  }
}

void GoogleWebTranslator::load(const ProcessingItem &item) {
  ST_ASSERT (!item.recognized.isEmpty ());
  if (translationLanguage_.isEmpty ()) {
    emit error (tr ("Неверные парметры для перевода."));
    return;
  }
  QUrl url (QString ("https://translate.google.com/#auto/%1/%2").arg(translationLanguage_, item.recognized));
  view_->setUrl(url);
}