// From Qt5 Examples/Docs

#include"dl-man.h"

DownloadManager::DownloadManager()
{
    connect(&manager, SIGNAL(finished(QNetworkReply*)),
            SLOT(downloadFinished(QNetworkReply*)));
}

void DownloadManager::doDownload(const QUrl &url)
{
    QNetworkRequest request(url);
    QNetworkReply *reply = manager.get(request);
    
    connect(reply, SIGNAL(sslErrors(QList<QSslError>)),
            SLOT(sslErrors(QList<QSslError>)));
    
    currentDownloads.append(reply);
}

QString DownloadManager::saveFileName(const QUrl &url)
{
    QString path = url.path();
    QString basename = QFileInfo(path).fileName();
    
    if (basename.isEmpty())
        basename = "download";
    
    return basename;
}

bool DownloadManager::saveToDisk(const QString &filename, QIODevice *data)
{
    QFile file(filename);
    if (!file.open(QIODevice::WriteOnly)) {
        fprintf(stderr, "Could not open %s for writing: %s\n",
                qPrintable(filename),
                qPrintable(file.errorString()));
        return false;
    }
    file.write(data->readAll());
    file.close();
    return true;
}

bool DownloadManager::isHttpRedirect(QNetworkReply *reply)
{
    int statusCode = reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt();
    return statusCode == 301 || statusCode == 302 || statusCode == 303
    || statusCode == 305 || statusCode == 307 || statusCode == 308;
}

void DownloadManager::execute() {}

void DownloadManager::sslErrors(const QList<QSslError> &sslErrors)
{
    for (const QSslError &error : sslErrors)
        fprintf(stderr, "SSL error: %s\n", qPrintable(error.errorString()));
}

void DownloadManager::downloadFinished(QNetworkReply *reply)
{
    QUrl url = reply->url();
    if (reply->error()) {
        fprintf(stderr, "Download of %s failed: %s\n",
                url.toEncoded().constData(),
                qPrintable(reply->errorString()));
    } else {
        if (isHttpRedirect(reply)) {
            fputs("Request was redirected.\n", stderr);
        } else {
            QString filename = saveFileName(url);
            if (saveToDisk(filename, reply)) {
                printf("Download of %s succeeded (saved to %s)\n",
                       url.toEncoded().constData(), qPrintable(filename));
            }
        }
    }
    reply->deleteLater();
}