Add enums for describing plugin status:

PLUGIN_STATE
RESULT_STATE
CASH_STATE
TICKET_VARIANT
STEP
TERMINAL_STATE.
Add default implementation for getPluginInfo().

src/ATBAPP/ATBAPPplugin.h

@@ -7,19 +7,61 @@
 #include <QObject>
 #include <QStringList>
 
-class ATBAPPplugin
-{
+struct ATBAPPplugin {
+    enum class PLUGIN_STATE : quint8 {
+        NOT_INITIALIZED = 0,
+        INITIALIZED = 1
+    };
+    enum class RESULT_STATE : quint8 {
+        SUCCESS = 1,                // operation was successfull
+        ERROR_BACKEND,              // error from backend (e.g. backend replies with error)
+        ERROR_NETWORK,
+        ERROR_TIMEOUT,              // the operation timed out
+        ERROR_PROCESS,              // internal plugin error, should not occur (this is a bug in implementation)
+        ERROR_BUSY,
+        ERROR_STATE,
+        ERROR_RETRY,                // retry operation
+        INFO                        // informational (e.g. display a message, log something etc.)
+    };
+    enum class CASH_STATE   : quint8 {
+        CACHE_EMPTY,                // Cache still empty, default state
+        CACHE_INPUT,                // Coins are in Cache
+        OVERPAYED,
+        /* t.b.d. */
+    };
+    enum class TICKET_VARIANT : quint8 {
+        PARKING_TICKET,
+        RECEIPT,
+        ERROR_RECEIPT,
+        START_RECEIPT,   // e.g. Szeged Start
+        STOP_RECEIPT,    // e.g. Szeged Stop
+    };
+    enum class STEP : quint8 {
+        UP = 1,
+        DOWN = 2
+    };
+    enum class TERMINAL_STATE : quint8 {
+        NOT_AVAILABLE = 1,
+        AVAILABLE,
+        PREPARED_FOR_VENDING,
+        BUSY,
+        NEEDS_MAINTENANCE
+    };
 
-public:
-    explicit ATBAPPplugin() = default;
-    virtual ~ATBAPPplugin() = default;
-
-    virtual QStringList getPluginInfo() = 0;
+    virtual const QString &getPluginInfo() = 0;
+    virtual QStringList getPluginInfoList() {
+        return QStringList(QString());
+    }
 };
 
+using PLUGIN_STATE = ATBAPPplugin::PLUGIN_STATE;
+using RESULT_STATE = ATBAPPplugin::RESULT_STATE;
+using CASH_STATE = ATBAPPplugin::CASH_STATE;
+using TICKET_VARIANT = ATBAPPplugin::TICKET_VARIANT;
+using STEP = ATBAPPplugin::STEP;
+using TERMINAL_STATE = ATBAPPplugin::TERMINAL_STATE;
+
 Q_DECLARE_INTERFACE(ATBAPPplugin,
                     "eu.atb.ptu.plugin.ATBAPPplugin/0.9")
 
-
-
 #endif // ATBAPPPLUGIN_H