From b2a532be62c66061d2c76447f0aca3b10d920e21 Mon Sep 17 00:00:00 2001
From: John Maguire <john.maguire@gmail.com>
Date: Mon, 20 Jul 2015 14:35:13 +0100
Subject: [PATCH] Experiment with typesafe time units

---
 ext/libclementine-common/core/closure.cpp | 10 ----------
 ext/libclementine-common/core/closure.h   | 16 +++++++++++++++-
 ext/libclementine-common/core/logging.cpp | 14 ++++++++++++++
 ext/libclementine-common/core/logging.h   |  5 +++++
 src/internet/amazon/amazonclouddrive.cpp  |  8 +++++---
 5 files changed, 39 insertions(+), 14 deletions(-)

diff --git a/ext/libclementine-common/core/closure.cpp b/ext/libclementine-common/core/closure.cpp
index 477c3868d..ff0ed120f 100644
--- a/ext/libclementine-common/core/closure.cpp
+++ b/ext/libclementine-common/core/closure.cpp
@@ -17,8 +17,6 @@
 
 #include "closure.h"
 
-#include <QTimer>
-
 #include "core/timeconstants.h"
 
 namespace _detail {
@@ -65,11 +63,3 @@ void DoInAMinuteOrSo(QObject* receiver, const char* slot) {
   int msec = (60 + (qrand() % 60)) * kMsecPerSec;
   DoAfter(receiver, slot, msec);
 }
-
-void DoAfter(std::function<void()> callback, int msec) {
-  QTimer* timer = new QTimer;
-  timer->setSingleShot(true);
-  NewClosure(timer, SIGNAL(timeout()), callback);
-  QObject::connect(timer, SIGNAL(timeout()), timer, SLOT(deleteLater()));
-  timer->start(msec);
-}
diff --git a/ext/libclementine-common/core/closure.h b/ext/libclementine-common/core/closure.h
index c01d2fc96..d52370757 100644
--- a/ext/libclementine-common/core/closure.h
+++ b/ext/libclementine-common/core/closure.h
@@ -18,12 +18,14 @@
 #ifndef CLOSURE_H
 #define CLOSURE_H
 
+#include <chrono>
 #include <functional>
 #include <memory>
 
 #include <QMetaMethod>
 #include <QObject>
 #include <QSharedPointer>
+#include <QTimer>
 
 namespace _detail {
 
@@ -188,7 +190,19 @@ _detail::ClosureBase* NewClosure(QObject* sender, const char* signal,
 }
 
 void DoAfter(QObject* receiver, const char* slot, int msec);
-void DoAfter(std::function<void()> callback, int msec);
+void DoAfter(std::function<void()> callback, std::chrono::milliseconds msec);
 void DoInAMinuteOrSo(QObject* receiver, const char* slot);
 
+template <typename R, typename P>
+void DoAfter(
+    std::function<void()> callback, std::chrono::duration<R, P> duration) {
+  QTimer* timer = new QTimer;
+  timer->setSingleShot(true);
+  NewClosure(timer, SIGNAL(timeout()), callback);
+  QObject::connect(timer, SIGNAL(timeout()), timer, SLOT(deleteLater()));
+  std::chrono::milliseconds msec =
+      std::chrono::duration_cast<std::chrono::milliseconds>(duration);
+  timer->start(msec.count());
+}
+
 #endif  // CLOSURE_H
diff --git a/ext/libclementine-common/core/logging.cpp b/ext/libclementine-common/core/logging.cpp
index acbc0e2f0..ec8faa267 100644
--- a/ext/libclementine-common/core/logging.cpp
+++ b/ext/libclementine-common/core/logging.cpp
@@ -266,3 +266,17 @@ void DumpStackTrace() {
 }
 
 }  // namespace logging
+
+namespace {
+
+template<typename T>
+QString print_duration(T duration, const std::string& unit) {
+  return QString("%1%2").arg(duration.count()).arg(unit.c_str());
+}
+
+}  // namespace
+
+QDebug operator<<(QDebug dbg, std::chrono::seconds secs) {
+  dbg.nospace() << print_duration(secs, "s");
+  return dbg.space();
+}
diff --git a/ext/libclementine-common/core/logging.h b/ext/libclementine-common/core/logging.h
index 8cba187ea..21eebdf3a 100644
--- a/ext/libclementine-common/core/logging.h
+++ b/ext/libclementine-common/core/logging.h
@@ -21,6 +21,9 @@
 #ifndef LOGGING_H
 #define LOGGING_H
 
+#include <chrono>
+#include <string>
+
 #include <QDebug>
 
 #ifdef QT_NO_DEBUG_STREAM
@@ -61,4 +64,6 @@ void GLog(const char* domain, int level, const char* message, void* user_data);
 extern const char* kDefaultLogLevels;
 }
 
+QDebug operator<<(QDebug debug, std::chrono::seconds secs);
+
 #endif  // LOGGING_H
diff --git a/src/internet/amazon/amazonclouddrive.cpp b/src/internet/amazon/amazonclouddrive.cpp
index a373799a5..257d6a539 100644
--- a/src/internet/amazon/amazonclouddrive.cpp
+++ b/src/internet/amazon/amazonclouddrive.cpp
@@ -17,6 +17,7 @@
 
 #include "internet/amazon/amazonclouddrive.h"
 
+#include <chrono>
 #include <cmath>
 
 #include <QtGlobal>
@@ -37,6 +38,7 @@
 #include "library/librarybackend.h"
 #include "ui/settingsdialog.h"
 
+using std::chrono::seconds;
 using std::placeholders::_1;
 
 const char* AmazonCloudDrive::kServiceName = "Amazon Cloud Drive";
@@ -197,16 +199,16 @@ void AmazonCloudDrive::MonitorReply(QNetworkReply* reply,
           reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt();
       if (code >= 500) {  // Retry with exponential backoff.
         int max_delay_s = std::pow(std::min(retries + 1, 8), 2);
-        int delay_s = qrand() % max_delay_s;
+        seconds delay(qrand() % max_delay_s);
         qLog(Debug) << "Request failed with code:" << code << "- retrying after"
-                    << delay_s << "seconds";
+                    << delay << "seconds";
         DoAfter([=]() {
           if (post_data.isEmpty()) {
             Get(reply->request(), done, retries + 1);
           } else {
             Post(reply->request(), post_data, done, retries + 1);
           }
-        }, delay_s * kMsecPerSec);
+        }, delay);
       } else {
         // Request failed permanently.
         done(reply);