summaryrefslogtreecommitdiffstats
path: root/examples/network/torrent/mainwindow.cpp
blob: 3e5c912c2954db2d7f64a5b014bbc300dcaeaa54 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the either Technology Preview License Agreement or the
** Beta Release License Agreement.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain
** additional rights. These rights are described in the Nokia Qt LGPL
** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
** package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you are unsure which license is appropriate for your use, please
** contact the sales department at http://www.qtsoftware.com/contact.
** $QT_END_LICENSE$
**
****************************************************************************/

#include <QtGui>

#include "addtorrentdialog.h"
#include "mainwindow.h"
#include "ratecontroller.h"
#include "torrentclient.h"

// TorrentView extends QTreeWidget to allow drag and drop.
class TorrentView : public QTreeWidget
{
    Q_OBJECT
public:
    TorrentView(QWidget *parent = 0);

signals:
    void fileDropped(const QString &fileName);

protected:
    void dragMoveEvent(QDragMoveEvent *event);
    void dropEvent(QDropEvent *event);
};

// TorrentViewDelegate is used to draw the progress bars.
class TorrentViewDelegate : public QItemDelegate
{
    Q_OBJECT
public:
    inline TorrentViewDelegate(MainWindow *mainWindow) : QItemDelegate(mainWindow) {}

    inline void paint(QPainter *painter, const QStyleOptionViewItem &option,
                      const QModelIndex &index ) const
    {
        if (index.column() != 2) {
            QItemDelegate::paint(painter, option, index);
            return;
        }

        // Set up a QStyleOptionProgressBar to precisely mimic the
        // environment of a progress bar.
        QStyleOptionProgressBar progressBarOption;
        progressBarOption.state = QStyle::State_Enabled;
        progressBarOption.direction = QApplication::layoutDirection();
        progressBarOption.rect = option.rect;
        progressBarOption.fontMetrics = QApplication::fontMetrics();
        progressBarOption.minimum = 0;
        progressBarOption.maximum = 100;
        progressBarOption.textAlignment = Qt::AlignCenter;
        progressBarOption.textVisible = true;

        // Set the progress and text values of the style option.
        int progress = qobject_cast<MainWindow *>(parent())->clientForRow(index.row())->progress();
        progressBarOption.progress = progress < 0 ? 0 : progress;
        progressBarOption.text = QString().sprintf("%d%%", progressBarOption.progress);

        // Draw the progress bar onto the view.
        QApplication::style()->drawControl(QStyle::CE_ProgressBar, &progressBarOption, painter);
    }
};

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent), quitDialog(0), saveChanges(false)
{
    // Initialize some static strings
    QStringList headers;
    headers << tr("Torrent") << tr("Peers/Seeds") << tr("Progress")
            << tr("Down rate") << tr("Up rate") << tr("Status");

    // Main torrent list
    torrentView = new TorrentView(this);
    torrentView->setItemDelegate(new TorrentViewDelegate(this));
    torrentView->setHeaderLabels(headers);
    torrentView->setSelectionBehavior(QAbstractItemView::SelectRows);
    torrentView->setAlternatingRowColors(true);
    torrentView->setRootIsDecorated(false);
    setCentralWidget(torrentView);

    // Set header resize modes and initial section sizes
    QFontMetrics fm = fontMetrics();
    QHeaderView *header = torrentView->header();
    header->resizeSection(0, fm.width("typical-name-for-a-torrent.torrent"));
    header->resizeSection(1, fm.width(headers.at(1) + "  "));
    header->resizeSection(2, fm.width(headers.at(2) + "  "));
    header->resizeSection(3, qMax(fm.width(headers.at(3) + "  "), fm.width(" 1234.0 KB/s ")));
    header->resizeSection(4, qMax(fm.width(headers.at(4) + "  "), fm.width(" 1234.0 KB/s ")));
    header->resizeSection(5, qMax(fm.width(headers.at(5) + "  "), fm.width(tr("Downloading") + "  ")));

    // Create common actions
    QAction *newTorrentAction = new QAction(QIcon(":/icons/bottom.png"), tr("Add &new torrent"), this);
    pauseTorrentAction = new QAction(QIcon(":/icons/player_pause.png"), tr("&Pause torrent"), this);
    removeTorrentAction = new QAction(QIcon(":/icons/player_stop.png"), tr("&Remove torrent"), this);
    
    // File menu
    QMenu *fileMenu = menuBar()->addMenu(tr("&File"));
    fileMenu->addAction(newTorrentAction);
    fileMenu->addAction(pauseTorrentAction);
    fileMenu->addAction(removeTorrentAction);
    fileMenu->addSeparator();
    fileMenu->addAction(QIcon(":/icons/exit.png"), tr("E&xit"), this, SLOT(close()));

    // Help menu
    QMenu *helpMenu = menuBar()->addMenu(tr("&Help"));
    helpMenu->addAction(tr("&About"), this, SLOT(about()));
    helpMenu->addAction(tr("About &Qt"), qApp, SLOT(aboutQt()));

    // Top toolbar
    QToolBar *topBar = new QToolBar(tr("Tools"));
    addToolBar(Qt::TopToolBarArea, topBar);
    topBar->setMovable(false);
    topBar->addAction(newTorrentAction);
    topBar->addAction(removeTorrentAction);
    topBar->addAction(pauseTorrentAction);
    topBar->addSeparator();
    downActionTool = topBar->addAction(QIcon(tr(":/icons/1downarrow.png")), tr("Move down"));
    upActionTool = topBar->addAction(QIcon(tr(":/icons/1uparrow.png")), tr("Move up"));

    // Bottom toolbar
    QToolBar *bottomBar = new QToolBar(tr("Rate control"));
    addToolBar(Qt::BottomToolBarArea, bottomBar);
    bottomBar->setMovable(false);
    downloadLimitSlider = new QSlider(Qt::Horizontal);
    downloadLimitSlider->setRange(0, 1000);
    bottomBar->addWidget(new QLabel(tr("Max download:")));
    bottomBar->addWidget(downloadLimitSlider);
    bottomBar->addWidget((downloadLimitLabel = new QLabel(tr("0 KB/s"))));
    downloadLimitLabel->setFixedSize(QSize(fm.width(tr("99999 KB/s")), fm.lineSpacing()));
    bottomBar->addSeparator();
    uploadLimitSlider = new QSlider(Qt::Horizontal);
    uploadLimitSlider->setRange(0, 1000);
    bottomBar->addWidget(new QLabel(tr("Max upload:")));
    bottomBar->addWidget(uploadLimitSlider);
    bottomBar->addWidget((uploadLimitLabel = new QLabel(tr("0 KB/s"))));
    uploadLimitLabel->setFixedSize(QSize(fm.width(tr("99999 KB/s")), fm.lineSpacing()));

    // Set up connections
    connect(torrentView, SIGNAL(itemSelectionChanged()),
            this, SLOT(setActionsEnabled()));
    connect(torrentView, SIGNAL(fileDropped(const QString &)),
            this, SLOT(acceptFileDrop(const QString &)));
    connect(uploadLimitSlider, SIGNAL(valueChanged(int)),
            this, SLOT(setUploadLimit(int)));
    connect(downloadLimitSlider, SIGNAL(valueChanged(int)),
            this, SLOT(setDownloadLimit(int)));
    connect(newTorrentAction, SIGNAL(triggered()),
            this, SLOT(addTorrent()));
    connect(pauseTorrentAction, SIGNAL(triggered()),
            this, SLOT(pauseTorrent()));
    connect(removeTorrentAction, SIGNAL(triggered()),
            this, SLOT(removeTorrent()));
    connect(upActionTool, SIGNAL(triggered(bool)),
            this, SLOT(moveTorrentUp()));
    connect(downActionTool, SIGNAL(triggered(bool)),
            this, SLOT(moveTorrentDown()));

    // Load settings and start
    setWindowTitle(tr("Torrent Client"));
    setActionsEnabled();
    QMetaObject::invokeMethod(this, "loadSettings", Qt::QueuedConnection);
}

QSize MainWindow::sizeHint() const
{
    const QHeaderView *header = torrentView->header();

    // Add up the sizes of all header sections. The last section is
    // stretched, so its size is relative to the size of the width;
    // instead of counting it, we count the size of its largest value.
    int width = fontMetrics().width(tr("Downloading") + "  ");
    for (int i = 0; i < header->count() - 1; ++i)
        width += header->sectionSize(i);

    return QSize(width, QMainWindow::sizeHint().height())
        .expandedTo(QApplication::globalStrut());
}

const TorrentClient *MainWindow::clientForRow(int row) const
{
    // Return the client at the given row.
    return jobs.at(row).client;
}

int MainWindow::rowOfClient(TorrentClient *client) const
{
    // Return the row that displays this client's status, or -1 if the
    // client is not known.
    int row = 0;
    foreach (Job job, jobs) {
        if (job.client == client)
            return row;
        ++row;
    }
    return -1;
}

void MainWindow::loadSettings()
{
    // Load base settings (last working directory, upload/download limits).
    QSettings settings("Trolltech", "Torrent");
    lastDirectory = settings.value("LastDirectory").toString();
    if (lastDirectory.isEmpty())
        lastDirectory = QDir::currentPath();
    int up = settings.value("UploadLimit").toInt();
    int down = settings.value("DownloadLimit").toInt();
    uploadLimitSlider->setValue(up ? up : 170);
    downloadLimitSlider->setValue(down ? down : 550);

    // Resume all previous downloads.
    int size = settings.beginReadArray("Torrents");
    for (int i = 0; i < size; ++i) {
        settings.setArrayIndex(i);
        QByteArray resumeState = settings.value("resumeState").toByteArray();
        QString fileName = settings.value("sourceFileName").toString();
        QString dest = settings.value("destinationFolder").toString();

        if (addTorrent(fileName, dest, resumeState)) {
            TorrentClient *client = jobs.last().client;
            client->setDownloadedBytes(settings.value("downloadedBytes").toLongLong());
            client->setUploadedBytes(settings.value("uploadedBytes").toLongLong());
        }
    }
}

bool MainWindow::addTorrent()
{
    // Show the file dialog, let the user select what torrent to start downloading.
    QString fileName = QFileDialog::getOpenFileName(this, tr("Choose a torrent file"),
                                                    lastDirectory,
                                                    tr("Torrents (*.torrent);;"
                                                       " All files (*.*)"));
    if (fileName.isEmpty())
        return false;
    lastDirectory = QFileInfo(fileName).absolutePath();

    // Show the "Add Torrent" dialog.
    AddTorrentDialog *addTorrentDialog = new AddTorrentDialog(this);
    addTorrentDialog->setTorrent(fileName);
    addTorrentDialog->deleteLater();
    if (!addTorrentDialog->exec())
        return false;

    // Add the torrent to our list of downloads
    addTorrent(fileName, addTorrentDialog->destinationFolder());
    if (!saveChanges) {
        saveChanges = true;
        QTimer::singleShot(1000, this, SLOT(saveSettings()));
    }
    return true;
}

void MainWindow::removeTorrent()
{
    // Find the row of the current item, and find the torrent client
    // for that row.
    int row = torrentView->indexOfTopLevelItem(torrentView->currentItem());
    TorrentClient *client = jobs.at(row).client;

    // Stop the client.
    client->disconnect();
    connect(client, SIGNAL(stopped()), this, SLOT(torrentStopped()));
    client->stop();

    // Remove the row from the view.
    delete torrentView->takeTopLevelItem(row);
    jobs.removeAt(row);
    setActionsEnabled();

    saveChanges = true;
    saveSettings();
}

void MainWindow::torrentStopped()
{
    // Schedule the client for deletion.
    TorrentClient *client = qobject_cast<TorrentClient *>(sender());
    client->deleteLater();

    // If the quit dialog is shown, update its progress.
    if (quitDialog) {
        if (++jobsStopped == jobsToStop)
            quitDialog->close();
    }
}

void MainWindow::torrentError(TorrentClient::Error)
{
    // Delete the client.
    TorrentClient *client = qobject_cast<TorrentClient *>(sender());
    int row = rowOfClient(client);
    QString fileName = jobs.at(row).torrentFileName;
    jobs.removeAt(row);

    // Display the warning.
    QMessageBox::warning(this, tr("Error"),
                         tr("An error occurred while downloading %0: %1")
                         .arg(fileName)
                         .arg(client->errorString()));

    delete torrentView->takeTopLevelItem(row);
    client->deleteLater();
}

bool MainWindow::addTorrent(const QString &fileName, const QString &destinationFolder,
                            const QByteArray &resumeState)
{
    // Check if the torrent is already being downloaded.
    foreach (Job job, jobs) {
        if (job.torrentFileName == fileName && job.destinationDirectory == destinationFolder) {
            QMessageBox::warning(this, tr("Already downloading"),
                                 tr("The torrent file %1 is "
                                    "already being downloaded.").arg(fileName));
            return false;
        }
    }

    // Create a new torrent client and attempt to parse the torrent data.
    TorrentClient *client = new TorrentClient(this);
    if (!client->setTorrent(fileName)) {
        QMessageBox::warning(this, tr("Error"),
                             tr("The torrent file %1 cannot not be opened/resumed.").arg(fileName));
        delete client;
        return false;
    }
    client->setDestinationFolder(destinationFolder);
    client->setDumpedState(resumeState);

    // Setup the client connections.
    connect(client, SIGNAL(stateChanged(TorrentClient::State)), this, SLOT(updateState(TorrentClient::State)));
    connect(client, SIGNAL(peerInfoUpdated()), this, SLOT(updatePeerInfo()));
    connect(client, SIGNAL(progressUpdated(int)), this, SLOT(updateProgress(int)));
    connect(client, SIGNAL(downloadRateUpdated(int)), this, SLOT(updateDownloadRate(int)));
    connect(client, SIGNAL(uploadRateUpdated(int)), this, SLOT(updateUploadRate(int)));
    connect(client, SIGNAL(stopped()), this, SLOT(torrentStopped()));
    connect(client, SIGNAL(error(TorrentClient::Error)), this, SLOT(torrentError(TorrentClient::Error)));

    // Add the client to the list of downloading jobs.
    Job job;
    job.client = client;
    job.torrentFileName = fileName;
    job.destinationDirectory = destinationFolder;
    jobs << job;

    // Create and add a row in the torrent view for this download.
    QTreeWidgetItem *item = new QTreeWidgetItem(torrentView);

    QString baseFileName = QFileInfo(fileName).fileName();
    if (baseFileName.toLower().endsWith(".torrent"))
        baseFileName.remove(baseFileName.size() - 8);

    item->setText(0, baseFileName);
    item->setToolTip(0, tr("Torrent: %1<br>Destination: %2")
                     .arg(baseFileName).arg(destinationFolder));
    item->setText(1, tr("0/0"));
    item->setText(2, "0");
    item->setText(3, "0.0 KB/s");
    item->setText(4, "0.0 KB/s");
    item->setText(5, tr("Idle"));
    item->setFlags(item->flags() & ~Qt::ItemIsEditable);
    item->setTextAlignment(1, Qt::AlignHCenter);

    if (!saveChanges) {
        saveChanges = true;
        QTimer::singleShot(5000, this, SLOT(saveSettings()));
    }
    client->start();
    return true;
}

void MainWindow::saveSettings()
{
    if (!saveChanges)
      return;
    saveChanges = false;

    // Prepare and reset the settings
    QSettings settings("Trolltech", "Torrent");
    settings.clear();

    settings.setValue("LastDirectory", lastDirectory);
    settings.setValue("UploadLimit", uploadLimitSlider->value());
    settings.setValue("DownloadLimit", downloadLimitSlider->value());

    // Store data on all known torrents
    settings.beginWriteArray("Torrents");
    for (int i = 0; i < jobs.size(); ++i) {
        settings.setArrayIndex(i);
        settings.setValue("sourceFileName", jobs.at(i).torrentFileName);
        settings.setValue("destinationFolder", jobs.at(i).destinationDirectory);
        settings.setValue("uploadedBytes", jobs.at(i).client->uploadedBytes());
        settings.setValue("downloadedBytes", jobs.at(i).client->downloadedBytes());
        settings.setValue("resumeState", jobs.at(i).client->dumpedState());
    }
    settings.endArray();
    settings.sync();
}

void MainWindow::updateState(TorrentClient::State)
{
    // Update the state string whenever the client's state changes.
    TorrentClient *client = qobject_cast<TorrentClient *>(sender());
    int row = rowOfClient(client);
    QTreeWidgetItem *item = torrentView->topLevelItem(row);
    if (item) {
        item->setToolTip(0, tr("Torrent: %1<br>Destination: %2<br>State: %3")
                         .arg(jobs.at(row).torrentFileName)
                         .arg(jobs.at(row).destinationDirectory)
                         .arg(client->stateString()));

        item->setText(5, client->stateString());
    }
    setActionsEnabled();
}

void MainWindow::updatePeerInfo()
{
    // Update the number of connected, visited, seed and leecher peers.
    TorrentClient *client = qobject_cast<TorrentClient *>(sender());
    int row = rowOfClient(client);

    QTreeWidgetItem *item = torrentView->topLevelItem(row);
    item->setText(1, tr("%1/%2").arg(client->connectedPeerCount())
                  .arg(client->seedCount()));
}

void MainWindow::updateProgress(int percent)
{
    TorrentClient *client = qobject_cast<TorrentClient *>(sender());
    int row = rowOfClient(client);

    // Update the progressbar.
    QTreeWidgetItem *item = torrentView->topLevelItem(row);
    if (item)
        item->setText(2, QString::number(percent));
}

void MainWindow::setActionsEnabled()
{
    // Find the view item and client for the current row, and update
    // the states of the actions.
    QTreeWidgetItem *item = 0;
    if (!torrentView->selectedItems().isEmpty())
        item = torrentView->selectedItems().first();
    TorrentClient *client = item ? jobs.at(torrentView->indexOfTopLevelItem(item)).client : 0;
    bool pauseEnabled = client && ((client->state() == TorrentClient::Paused)
                                       ||  (client->state() > TorrentClient::Preparing));

    removeTorrentAction->setEnabled(item != 0);
    pauseTorrentAction->setEnabled(item != 0 && pauseEnabled);

    if (client && client->state() == TorrentClient::Paused) {
        pauseTorrentAction->setIcon(QIcon(":/icons/player_play.png"));
        pauseTorrentAction->setText(tr("Resume torrent"));
    } else {
        pauseTorrentAction->setIcon(QIcon(":/icons/player_pause.png"));
        pauseTorrentAction->setText(tr("Pause torrent"));
    }

    int row = torrentView->indexOfTopLevelItem(item);
    upActionTool->setEnabled(item && row != 0);
    downActionTool->setEnabled(item && row != jobs.size() - 1);
}

void MainWindow::updateDownloadRate(int bytesPerSecond)
{
    // Update the download rate.
    TorrentClient *client = qobject_cast<TorrentClient *>(sender());
    int row = rowOfClient(client);
    QString num;
    num.sprintf("%.1f KB/s", bytesPerSecond / 1024.0);
    torrentView->topLevelItem(row)->setText(3, num);

    if (!saveChanges) {
        saveChanges = true;
        QTimer::singleShot(5000, this, SLOT(saveSettings()));
    }
}

void MainWindow::updateUploadRate(int bytesPerSecond)
{
    // Update the upload rate.
    TorrentClient *client = qobject_cast<TorrentClient *>(sender());
    int row = rowOfClient(client);
    QString num;
    num.sprintf("%.1f KB/s", bytesPerSecond / 1024.0);
    torrentView->topLevelItem(row)->setText(4, num);

    if (!saveChanges) {
        saveChanges = true;
        QTimer::singleShot(5000, this, SLOT(saveSettings()));
    }
}

void MainWindow::pauseTorrent()
{
    // Pause or unpause the current torrent.
    int row = torrentView->indexOfTopLevelItem(torrentView->currentItem());
    TorrentClient *client = jobs.at(row).client;
    client->setPaused(client->state() != TorrentClient::Paused);
    setActionsEnabled();
}

void MainWindow::moveTorrentUp()
{
    QTreeWidgetItem *item = torrentView->currentItem();
    int row = torrentView->indexOfTopLevelItem(item);
    if (row == 0)
        return;

    Job tmp = jobs.at(row - 1);
    jobs[row - 1] = jobs[row];
    jobs[row] = tmp;

    QTreeWidgetItem *itemAbove = torrentView->takeTopLevelItem(row - 1);
    torrentView->insertTopLevelItem(row, itemAbove);
    setActionsEnabled();
}

void MainWindow::moveTorrentDown()
{
    QTreeWidgetItem *item = torrentView->currentItem();
    int row = torrentView->indexOfTopLevelItem(item);
    if (row == jobs.size() - 1)
        return;

    Job tmp = jobs.at(row + 1);
    jobs[row + 1] = jobs[row];
    jobs[row] = tmp;

    QTreeWidgetItem *itemAbove = torrentView->takeTopLevelItem(row + 1);
    torrentView->insertTopLevelItem(row, itemAbove);
    setActionsEnabled();
}

static int rateFromValue(int value)
{
    int rate = 0;
    if (value >= 0 && value < 250) {
        rate = 1 + int(value * 0.124);
    } else if (value < 500) {
        rate = 32 + int((value - 250) * 0.384);
    } else if (value < 750) {
        rate = 128 + int((value - 500) * 1.536);
    } else {
        rate = 512 + int((value - 750) * 6.1445);
    }
    return rate;
}

void MainWindow::setUploadLimit(int value)
{
    int rate = rateFromValue(value);
    uploadLimitLabel->setText(tr("%1 KB/s").arg(QString().sprintf("%4d", rate)));
    RateController::instance()->setUploadLimit(rate * 1024);
}

void MainWindow::setDownloadLimit(int value)
{
    int rate = rateFromValue(value);
    downloadLimitLabel->setText(tr("%1 KB/s").arg(QString().sprintf("%4d", rate)));
    RateController::instance()->setDownloadLimit(rate * 1024);
}

void MainWindow::about()
{
    QLabel *icon = new QLabel;
    icon->setPixmap(QPixmap(":/icons/peertopeer.png"));

    QLabel *text = new QLabel;
    text->setWordWrap(true);
    text->setText("<p>The <b>Torrent Client</b> example demonstrates how to"
                  " write a complete peer-to-peer file sharing"
                  " application using Qt's network and thread classes.</p>"
                  "<p>This feature complete client implementation of"
                  " the BitTorrent protocol can efficiently"
                  " maintain several hundred network connections"
                  " simultaneously.</p>");

    QPushButton *quitButton = new QPushButton("OK");

    QHBoxLayout *topLayout = new QHBoxLayout;
    topLayout->setMargin(10);
    topLayout->setSpacing(10);
    topLayout->addWidget(icon);
    topLayout->addWidget(text);

    QHBoxLayout *bottomLayout = new QHBoxLayout;
    bottomLayout->addStretch();
    bottomLayout->addWidget(quitButton);
    bottomLayout->addStretch();

    QVBoxLayout *mainLayout = new QVBoxLayout;
    mainLayout->addLayout(topLayout);
    mainLayout->addLayout(bottomLayout);

    QDialog about(this);
    about.setModal(true);
    about.setWindowTitle(tr("About Torrent Client"));
    about.setLayout(mainLayout);

    connect(quitButton, SIGNAL(clicked()), &about, SLOT(close()));

    about.exec();
}

void MainWindow::acceptFileDrop(const QString &fileName)
{
    // Create and show the "Add Torrent" dialog.
    AddTorrentDialog *addTorrentDialog = new AddTorrentDialog;
    lastDirectory = QFileInfo(fileName).absolutePath();
    addTorrentDialog->setTorrent(fileName);
    addTorrentDialog->deleteLater();
    if (!addTorrentDialog->exec())
        return;

    // Add the torrent to our list of downloads.
    addTorrent(fileName, addTorrentDialog->destinationFolder());
    saveSettings();
}

void MainWindow::closeEvent(QCloseEvent *)
{
    if (jobs.isEmpty())
        return;

    // Save upload / download numbers.
    saveSettings();
    saveChanges = false;

    quitDialog = new QProgressDialog(tr("Disconnecting from trackers"), tr("Abort"), 0, jobsToStop, this);

    // Stop all clients, remove the rows from the view and wait for
    // them to signal that they have stopped.
    jobsToStop = 0;
    jobsStopped = 0;
    foreach (Job job, jobs) {
        ++jobsToStop;
        TorrentClient *client = job.client;
        client->disconnect();
        connect(client, SIGNAL(stopped()), this, SLOT(torrentStopped()));
        client->stop();
        delete torrentView->takeTopLevelItem(0);
    }

    if (jobsToStop > jobsStopped)
        quitDialog->exec();
    quitDialog->deleteLater();
    quitDialog = 0;
}

TorrentView::TorrentView(QWidget *parent)
    : QTreeWidget(parent)
{
    setAcceptDrops(true);
}

void TorrentView::dragMoveEvent(QDragMoveEvent *event)
{
    // Accept file actions with a '.torrent' extension.
    QUrl url(event->mimeData()->text());
    if (url.isValid() && url.scheme().toLower() == "file"
            && url.path().toLower().endsWith(".torrent"))
        event->acceptProposedAction();
}

void TorrentView::dropEvent(QDropEvent *event)
{
    // Accept drops if the file has a '.torrent' extension and it
    // exists.
    QString fileName = QUrl(event->mimeData()->text()).path();
    if (QFile::exists(fileName) && fileName.toLower().endsWith(".torrent"))
        emit fileDropped(fileName);
}

#include "mainwindow.moc"