From 53189eafd59a9210572678197bbf5ffe855e7739 Mon Sep 17 00:00:00 2001
From: Klaus Basan <klaus.basan@klausbasan.de>
Date: Tue, 15 Aug 2017 02:11:22 +0200
Subject: [PATCH] Ref T125, human readable file size

---
 src/blackmisc/fileutils.cpp      | 30 +++++++++++++++++++++++++-----
 src/blackmisc/fileutils.h        |  3 +++
 src/blackmisc/math/mathutils.cpp |  5 +++++
 src/blackmisc/math/mathutils.h   |  3 +++
 4 files changed, 36 insertions(+), 5 deletions(-)

diff --git a/src/blackmisc/fileutils.cpp b/src/blackmisc/fileutils.cpp
index ecacfb8c7..d274384e6 100644
--- a/src/blackmisc/fileutils.cpp
+++ b/src/blackmisc/fileutils.cpp
@@ -7,9 +7,11 @@
  * contained in the LICENSE file.
  */
 
-#include "blackconfig/buildconfig.h"
-#include "blackmisc/fileutils.h"
 #include "blackmisc/worker.h"
+#include "blackmisc/fileutils.h"
+#include "blackmisc/math/mathutils.h"
+
+#include "blackconfig/buildconfig.h"
 
 #include <QCoreApplication>
 #include <QDateTime>
@@ -23,6 +25,7 @@
 #include <algorithm>
 
 using namespace BlackConfig;
+using namespace BlackMisc::Math;
 
 namespace BlackMisc
 {
@@ -124,8 +127,8 @@ namespace BlackMisc
                 return false;
             }
 
-            QDir originDir(sourceFileInfo.absoluteFilePath());
-            auto fileNames = originDir.entryList(QDir::Files | QDir::Dirs | QDir::NoDotAndDotDot | QDir::Hidden | QDir::System);
+            const QDir originDir(sourceFileInfo.absoluteFilePath());
+            const auto fileNames = originDir.entryList(QDir::Files | QDir::Dirs | QDir::NoDotAndDotDot | QDir::Hidden | QDir::System);
             for (const QString &fileName : fileNames)
             {
                 if (!copyRecursively(originDir.absoluteFilePath(fileName), targetDir.absoluteFilePath(fileName)))
@@ -141,7 +144,6 @@ namespace BlackMisc
                 return false;
             }
         }
-
         return true;
     }
 
@@ -354,4 +356,22 @@ namespace BlackMisc
         static const QString f("/%1");
         return f.arg(filePath);
     }
+
+    QString CFileUtils::humanReadableFileSize(qint64 size)
+    {
+        // from https://stackoverflow.com/a/30958189/356726
+        // fell free to replace it by something better
+        static const QStringList units({ "KB", "MB", "GB", "TB" });
+        if (size <= 1024) { return QString::number(size); }
+
+        QStringListIterator i(units);
+        double currentSize = size;
+        QString unit;
+        while (currentSize >= 1024.0 && i.hasNext())
+        {
+            unit = i.next();
+            currentSize /= 1024.0;
+        }
+        return QString("%1 %2").arg(CMathUtils::roundAsString(currentSize, 2), unit);
+    }
 } // ns
diff --git a/src/blackmisc/fileutils.h b/src/blackmisc/fileutils.h
index 021e1e01c..e9790a181 100644
--- a/src/blackmisc/fileutils.h
+++ b/src/blackmisc/fileutils.h
@@ -130,6 +130,9 @@ namespace BlackMisc
         //! UNC file paths on Qt start with "/", but UNC file paths only work when they start with "//"
         //! \remark On Windows starting with "/" means an UNC path, on UNIX it varies, see http://unix.stackexchange.com/a/12291/19428
         static QString fixWindowsUncPath(const QString &filePath);
+
+        //! Human readable (GB, MB, ..) file size
+        static QString humanReadableFileSize(qint64 size);
     };
 } // ns
 
diff --git a/src/blackmisc/math/mathutils.cpp b/src/blackmisc/math/mathutils.cpp
index 859222f24..5b4a6d856 100644
--- a/src/blackmisc/math/mathutils.cpp
+++ b/src/blackmisc/math/mathutils.cpp
@@ -51,6 +51,11 @@ namespace BlackMisc
             return rv;
         }
 
+        QString CMathUtils::roundAsString(double value, int digits)
+        {
+            return QString::number(round(value, digits));
+        }
+
         double CMathUtils::roundEpsilon(double value, double epsilon)
         {
             if (epsilon == 0) { return value; } // avoid division by 0
diff --git a/src/blackmisc/math/mathutils.h b/src/blackmisc/math/mathutils.h
index 83ebb3d2d..666669a46 100644
--- a/src/blackmisc/math/mathutils.h
+++ b/src/blackmisc/math/mathutils.h
@@ -50,6 +50,9 @@ namespace BlackMisc
             //! Utility round method
             static double round(double value, int digits);
 
+            //! Utility round method, returning as string
+            static QString roundAsString(double value, int digits);
+
             //! Round by given epsilon
             static double roundEpsilon(double value, double epsilon);