[qt] Added current download speed indicator

platform/download_manager.hpp

@@ -14,6 +14,7 @@ struct HttpProgressT
   string m_url;
   int64_t m_current;
   int64_t m_total;
+  int64_t m_bytesPerSec;
 };
 typedef function<void (HttpProgressT const &)> HttpProgressCallbackT;
 

platform/qt_download.cpp

@@ -302,12 +302,23 @@ void QtDownload::OnHttpReadyRead()
 
 void QtDownload::OnUpdateDataReadProgress(qint64 bytesRead, qint64 totalBytes)
 {
+  m_urlGenerator.UpdateSpeed(bytesRead);
   if (m_params.m_progress)
   {
     HttpProgressT p;
     p.m_current = bytesRead;
     p.m_total = totalBytes;
     p.m_url = m_params.m_url;
+    p.m_bytesPerSec = m_urlGenerator.CurrentSpeed();
     m_params.m_progress(p);
   }
+  // if download speed is slow, use next server
+  string const fasterUrl = m_urlGenerator.GetFasterUrl();
+  if (!fasterUrl.empty())
+  {
+    m_reply->abort();
+    m_reply->deleteLater();
+    m_currentUrl.setUrl(fasterUrl.c_str());
+    StartRequest();
+  }
 }

platform/url_generator.cpp

@@ -38,12 +38,14 @@ static char const * g_defaultSecondGroup[] = {
 UrlGenerator::UrlGenerator()
   : m_randomGenerator(static_cast<uint32_t>(time(NULL))),
     m_firstGroup(&g_defaultFirstGroup[0], &g_defaultFirstGroup[0] + ARRAY_SIZE(g_defaultFirstGroup)),
-    m_secondGroup(&g_defaultSecondGroup[0], &g_defaultSecondGroup[0] + ARRAY_SIZE(g_defaultSecondGroup))
+    m_secondGroup(&g_defaultSecondGroup[0], &g_defaultSecondGroup[0] + ARRAY_SIZE(g_defaultSecondGroup)),
+    m_lastSecond(0.)
 {
 }
 
 UrlGenerator::UrlGenerator(vector<string> const & firstGroup, vector<string> const & secondGroup)
-  : m_randomGenerator(static_cast<uint32_t>(time(NULL))), m_firstGroup(firstGroup), m_secondGroup(secondGroup)
+  : m_randomGenerator(static_cast<uint32_t>(time(NULL))), m_firstGroup(firstGroup), m_secondGroup(secondGroup),
+    m_lastSecond(0.)
 {
 }
 
@@ -84,3 +86,31 @@ string UrlGenerator::PopNextUrl()
   }
   return s;
 }
+
+void UrlGenerator::UpdateSpeed(int64_t totalBytesRead)
+{
+  double const seconds = m_timer.ElapsedSeconds();
+  if (static_cast<int>(seconds) - static_cast<int>(m_lastSecond) > 0)
+  {
+    m_lastSecond = seconds;
+    m_speeds.push_back(make_pair(seconds, totalBytesRead));
+    if (m_speeds.size() > 6)
+      m_speeds.pop_front();
+  }
+}
+
+int64_t UrlGenerator::CurrentSpeed() const
+{
+  switch (m_speeds.size())
+  {
+  case 0:
+  case 1: return -1;
+  default: return static_cast<int64_t>((m_speeds.back().second - m_speeds.front().second)
+                                       / (m_speeds.back().first - m_speeds.front().first));
+  }
+}
+
+string UrlGenerator::GetFasterUrl()
+{
+  return string();
+}

platform/url_generator.hpp

@@ -1,9 +1,12 @@
 #pragma once
 
 #include "../base/pseudo_random.hpp"
+#include "../base/timer.hpp"
 
 #include "../std/vector.hpp"
+#include "../std/list.hpp"
 #include "../std/string.hpp"
+#include "../std/utility.hpp"
 
 class UrlGenerator
 {
@@ -11,9 +14,22 @@ class UrlGenerator
   vector<string> m_firstGroup;
   vector<string> m_secondGroup;
 
+  /// For moving average speed calculations
+  my::Timer m_timer;
+  /// Stores time in seconds from start and downloaded amount at that moment
+  typedef pair<double, int64_t> MarkT;
+  list<MarkT> m_speeds;
+  double m_lastSecond;
+
 public:
   UrlGenerator();
   explicit UrlGenerator(vector<string> const & firstGroup, vector<string> const & secondGroup);
+
   /// @return Always return empty string if all urls were already popped
   string PopNextUrl();
+
+  /// @return -1 means speed is unknown
+  void UpdateSpeed(int64_t totalBytesRead);
+  int64_t CurrentSpeed() const;
+  string GetFasterUrl();
 };

qt/update_dialog.cpp

@@ -307,7 +307,19 @@ namespace qt
   {
     QTreeWidgetItem * item = GetTreeItemByIndex(*m_tree, index);
     if (item)
-      item->setText(KColumnIndexSize, QString("%1%").arg(progress.m_current * 100 / progress.m_total));
+    {
+      QString speed;
+      if (progress.m_bytesPerSec > 1000 * 1000)
+        speed = QString(" %1 MB/s").arg(QString::number(static_cast<double>(progress.m_bytesPerSec) / (1000.0 * 1000.0),
+                                                         'f', 1));
+      else if (progress.m_bytesPerSec > 1000)
+        speed = QString(" %1 kB/s").arg(progress.m_bytesPerSec / 1000);
+      else if (progress.m_bytesPerSec >= 0)
+        speed = QString(" %1 B/sec").arg(progress.m_bytesPerSec);
+
+      item->setText(KColumnIndexSize, QString("%1%%2").arg(progress.m_current * 100 / progress.m_total)
+                    .arg(speed));
+    }
   }
 
   void UpdateDialog::ShowDialog()