Turn things in common into separate libs.

Took 2 hours 27 minutes

libs/settings/src/card_counter_settings.cpp

@@ -0,0 +1,56 @@
+#include "../include/settings/card_counter_settings.h"
+
+#include <QColor>
+#include <QSettings>
+#include <QtMath>
+
+CardCounterSettings::CardCounterSettings(const QString &settingsPath, QObject *parent)
+    : SettingsManager(settingsPath + "global.ini", parent)
+{
+}
+
+void CardCounterSettings::setColor(int counterId, const QColor &color)
+{
+    QString key = QString("cards/counters/%1/color").arg(counterId);
+
+    if (settings.value(key).value<QColor>() == color)
+        return;
+
+    settings.setValue(key, color);
+    emit colorChanged(counterId, color);
+}
+
+QColor CardCounterSettings::color(int counterId) const
+{
+    QColor defaultColor;
+
+    if (counterId < 6) {
+        // Preserve legacy colors
+        defaultColor = QColor::fromHsv(counterId * 60, 150, 255);
+    } else {
+        // Future-proof support for more counters with pseudo-random colors
+        int h = (counterId * 37) % 360;
+        int s = 128 + 64 * qSin((counterId * 97) * 0.1);   // 64-192
+        int v = 196 + 32 * qSin((counterId * 101) * 0.07); // 164-228
+
+        defaultColor = QColor::fromHsv(h, s, v);
+    }
+
+    return settings.value(QString("cards/counters/%1/color").arg(counterId), defaultColor).value<QColor>();
+}
+
+QString CardCounterSettings::displayName(int counterId) const
+{
+    // Currently, card counters name are fixed to A, B, ..., Z, AA, AB, ...
+
+    auto nChars = 1 + counterId / 26;
+    QString str;
+    str.resize(nChars);
+
+    for (auto it = str.rbegin(); it != str.rend(); ++it) {
+        *it = QChar('A' + (counterId) % 26);
+        counterId /= 26;
+    }
+
+    return str;
+}