Factor pin-reading logic into a new set of classes.

Reader.h

@@ -0,0 +1,59 @@
+// "Readers" represent different methods for reading the state of a pin.
+// They also include debouncing logic using the Bounce2 library, when appropriate.
+
+#ifndef _READER_H_
+#define _READER_H_
+
+#include <Bounce2.h>
+#include <Mux.h>
+
+// The abstract base class - a very simple interface
+class Reader {
+ public:
+  Reader(bool inverted);
+
+  virtual bool Update() = 0; // should return true if the state of the pin has changed
+  bool On();
+
+ protected:
+  uint8_t getMode(bool pullup);
+
+  Bounce bouncer;
+  bool inverted;
+};
+
+
+// A standard reader; the button is connected directly to a switch
+class DirectReader {
+ public:
+  DirectReader(uint8_t pin, bool inverted = true);
+  bool Update();
+  bool On();
+};
+
+
+// The button is connected to a Multiplexer channel
+class MuxReader {
+ public:
+  MuxReader(uint8_t channel, Mux* mux, bool inverted = true);
+  bool Update();
+  bool On();
+
+ protected:
+  Mux * mux;
+};
+
+
+// The button is connected via a scan matrix
+// "row" should always be the input, with "col" the selecter.
+class MatrixReader {
+ public:
+  MatrixReader(uint8_t row, uint8_t col, bool inverted = true);
+  bool Update();
+  bool On();
+
+ protected:
+  uint8_t col;
+};
+
+#endif