Theme manager

This is the first implementation of a theme manager. It’s a rebased and
revisited version of #792.

cockatrice/src/thememanager.h

@@ -0,0 +1,42 @@
+#ifndef THEMEMANAGER_H
+#define THEMEMANAGER_H
+
+#include <QObject>
+#include <QBrush>
+#include <QPixmap>
+#include <QMap>
+#include <QDir>
+#include <QString>
+
+typedef QMap<QString, QString> QStringMap;
+
+class QApplication;
+
+class ThemeManager : public QObject {
+    Q_OBJECT
+public:
+    ThemeManager(QObject *parent = 0);
+private:
+    QBrush handBgBrush, stackBgBrush, tableBgBrush, playerBgBrush;
+    QPixmap cardBackPixmap;
+    QStringMap availableThemes;
+protected:
+    void ensureThemeDirectoryExists();
+    QBrush loadBrush(QDir dir, QString fileName, QColor fallbackColor);
+    QPixmap loadPixmap(QDir dir, QString fileName);
+public:
+    QBrush &getHandBgBrush() { return handBgBrush; }
+    QBrush &getStackBgBrush() { return stackBgBrush; }
+    QBrush &getTableBgBrush() { return tableBgBrush; }
+    QBrush &getPlayerBgBrush() { return playerBgBrush; }
+    QPixmap &getCardBackPixmap() { return cardBackPixmap; }
+    QStringMap &getAvailableThemes();
+protected slots:
+    void themeChangedSlot();
+signals:
+    void themeChanged();
+};
+
+extern ThemeManager * themeManager;
+
+#endif