src/base/utils/compare.h

   1 /*
   2  * Bittorrent Client using Qt and libtorrent.
   3  * Copyright (C) 2021  Mike Tzou (Chocobo1)
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; either version 2
   8  * of the License, or (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  18  *
  19  * In addition, as a special exception, the copyright holders give permission to
  20  * link this program with the OpenSSL project's "OpenSSL" library (or with
  21  * modified versions of it that use the same license as the "OpenSSL" library),
  22  * and distribute the linked executables. You must obey the GNU General Public
  23  * License in all respects for all of the code used other than "OpenSSL".  If you
  24  * modify file(s), you may extend this exception to your version of the file(s),
  25  * but you are not obligated to do so. If you do not wish to do so, delete this
  26  * exception statement from your version.
  27  */
  28
  29 #pragma once
  30
  31 #include <Qt>
  32 #include <QtSystemDetection>
  33
  34 // for QT_FEATURE_xxx, see: https://wiki.qt.io/Qt5_Build_System#How_to
  35 #include <QtCore/private/qtcore-config_p.h>
  36
  37 #ifndef QBT_USE_QCOLLATOR
  38 // macOS and Windows support 'case sensitivity' and 'numeric mode' natively
  39 // https://github.com/qt/qtbase/blob/6.0/src/corelib/CMakeLists.txt#L777-L793
  40 // https://github.com/qt/qtbase/blob/6.0/src/corelib/text/qcollator_macx.cpp#L74-L77
  41 // https://github.com/qt/qtbase/blob/6.0/src/corelib/text/qcollator_win.cpp#L72-L78
  42 #if ((QT_FEATURE_icu == 1) || defined(Q_OS_MACOS) || defined(Q_OS_WIN))
  43 #define QBT_USE_QCOLLATOR 1
  44 #include <QCollator>
  45 #else
  46 #define QBT_USE_QCOLLATOR 0
  47 #endif
  48 #endif
  49
  50 class QString;
  51
  52 namespace Utils::Compare
  53 {
  54     int naturalCompare(const QString &left, const QString &right, Qt::CaseSensitivity caseSensitivity);
  55
  56     template <Qt::CaseSensitivity caseSensitivity>
  57     class NaturalCompare
  58     {
  59     public:
  60 #if (QBT_USE_QCOLLATOR == 0)
  61         int operator()(const QString &left, const QString &right) const
  62         {
  63             return naturalCompare(left, right, caseSensitivity);
  64         }
  65 #else
  66         NaturalCompare()
  67         {
  68             m_collator.setNumericMode(true);
  69             m_collator.setCaseSensitivity(caseSensitivity);
  70         }
  71
  72         int operator()(const QString &left, const QString &right) const
  73         {
  74             return m_collator.compare(left, right);
  75         }
  76
  77     private:
  78         QCollator m_collator;
  79 #endif
  80     };
  81
  82     template <Qt::CaseSensitivity caseSensitivity>
  83     class NaturalLessThan
  84     {
  85     public:
  86         bool operator()(const QString &left, const QString &right) const
  87         {
  88             return (m_comparator(left, right) < 0);
  89         }
  90
  91     private:
  92         NaturalCompare<caseSensitivity> m_comparator;
  93     };
  94 }