Implement XEP-0392: Consistent Color Generation

Author: lnjX

doc/doap.xml

@@ -611,6 +611,14 @@ SPDX-License-Identifier: CC0-1.0
         <xmpp:since>1.7</xmpp:since>
       </xmpp:SupportedXep>
     </implements>
+    <implements>
+      <xmpp:SupportedXep>
+        <xmpp:xep rdf:resource='https://xmpp.org/extensions/xep-0392.html'/>
+        <xmpp:status>complete</xmpp:status>
+        <xmpp:version>1.0.0</xmpp:version>
+        <xmpp:since>1.10</xmpp:since>
+      </xmpp:SupportedXep>
+    </implements>
     <implements>
       <xmpp:SupportedXep>
         <xmpp:xep rdf:resource='https://xmpp.org/extensions/xep-0405.html'/>

src/CMakeLists.txt

@@ -19,6 +19,7 @@ set(INSTALL_HEADER_FILES
     base/QXmppBitsOfBinaryIq.h
     base/QXmppBookmarkSet.h
     base/QXmppByteStreamIq.h
+    base/QXmppColorGeneration.h
     base/QXmppDataForm.h
     base/QXmppDataFormBase.h
     base/QXmppDiscoveryIq.h
@@ -174,6 +175,7 @@ set(SOURCE_FILES
     base/QXmppBitsOfBinaryIq.cpp
     base/QXmppBookmarkSet.cpp
     base/QXmppByteStreamIq.cpp
+    base/QXmppColorGeneration.cpp
     base/QXmppDataForm.cpp
     base/QXmppDataFormBase.cpp
     base/QXmppDiscoveryIq.cpp
@@ -237,6 +239,7 @@ set(SOURCE_FILES
     base/QXmppVCardIq.cpp
     base/QXmppVersionIq.cpp
     base/compat/removed_api.cpp
+    base/hsluv/hsluv.c
     # to trigger MOC
     base/XmppSocket.h
 

src/base/QXmppColorGeneration.cpp

@@ -0,0 +1,30 @@
+// SPDX-FileCopyrightText: 2019 Linus Jahn <[email protected]>
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+
+#include "QXmppColorGeneration.h"
+
+#include "hsluv/hsluv.h"
+
+#include <QCryptographicHash>
+
+QXmppColorGeneration::Rgb QXmppColorGeneration::generateRgb(QStringView str)
+{
+    QByteArray input = str.toUtf8();
+
+    // hash input through SHA-1
+    auto hashValue = QCryptographicHash::hash(str.toUtf8(), QCryptographicHash::Sha1);
+
+    // the first two bytes are used to calculate the angle/hue
+    int angle = hashValue.at(0) + hashValue.at(1) * 256;
+
+    double hue = double(angle) / 65536.0 * 360.0;
+    double saturation = 100.0;
+    double lightness = 50.0;
+
+    // convert to rgb values (values are between 0.0 and 1.0)
+    double red, green, blue = 0.0;
+    hsluv2rgb(hue, saturation, lightness, &red, &green, &blue);
+
+    return Rgb { quint8(red * 255.0), quint8(green * 255.0), quint8(blue * 255.0) };
+}

src/base/QXmppColorGeneration.h

@@ -0,0 +1,34 @@
+// SPDX-FileCopyrightText: 2019 Linus Jahn <[email protected]>
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+
+#ifndef QXMPPCOLORGENERATION_H
+#define QXMPPCOLORGENERATION_H
+
+#include "QXmppGlobal.h"
+
+#ifdef QT_GUI_LIB
+#include <QColor>
+#endif
+
+class QXmppColorGeneration
+{
+public:
+    struct Rgb {
+        quint8 red;
+        quint8 green;
+        quint8 blue;
+    };
+
+    static Rgb generateRgb(QStringView str);
+
+#ifdef QT_GUI_LIB
+    static QColor generateColor(QStringView str)
+    {
+        auto rgb = generateRgb(str);
+        return QColor(rgb.red, rgb.green, rgb.blue);
+    }
+#endif
+};
+
+#endif  // QXMPPCOLORGENERATION_H