make Gpio configuration dynamic

Gpio.h

@@ -3,13 +3,37 @@
 
 #include "NukiWrapper.h"
 
+enum class PinRole
+{
+    Undefined,
+    InputLock,
+    InputUnlock,
+    InputUnlatch,
+    OutputHighLocked,
+    OutputHighUnlocked,
+};
+
+struct PinEntry
+{
+    uint8_t pin = 0;
+    PinRole role = PinRole::Undefined;
+};
+
 class Gpio
 {
 public:
-    Gpio() = delete;
+    Gpio(Preferences* preferences, NukiWrapper* nuki);
     static void init(NukiWrapper* nuki);
 
+    void loadPinConfiguration();
+    void savePinConfiguration(const std::vector<PinEntry>& pinConfiguration);
+
+    const std::vector<uint8_t>& availablePins() const;
+
 private:
+    const std::vector<uint8_t> _availablePins = { 2, 4, 5, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 32, 33 };
+
+    std::vector<PinEntry> _pinConfiguration;
     static const uint _debounceTime;
 
     static void IRAM_ATTR isrLock();
@@ -19,4 +43,6 @@ private:
     static Gpio* _inst;
     static NukiWrapper* _nuki;
     static unsigned long _lockedTs;
+
+    Preferences* _preferences = nullptr;
 };