trying to cleanup code a bit

coffee-machine.ino

@@ -1,52 +1,16 @@
 #include <SoftwareSerial.h>
 #include "coffee-pins.hh"
 
-class LevelSensor
-{
-public:
-    LevelSensor(int pin) : sensePin_(pin) {}
-
-    bool checkState()
-    {
-        bool measured = digitalRead(sensePin_);
-        measured = failOpen_ ? !measured : measured;
-
-        uint64_t curTime = millis();
-
-        if (measured == curState_)
-        {
-            transitionTime = curTime;
-        }
-
-        if (curTime - transitionTime_ > debounceTime_)
-        {
-            transitionTime = curTime; 
-            curState_ = measured;
-        }
-
-        return curState_;
-    }
-
-private:
-    int sensePin_;
-    bool failOpen_;
-    uint64_t transitionTime_;
-    bool curState_;
-    static constexpr debounceTime_ = 250; // millis
-};
-
-
 enum class States { Standby, Pump, Failure };
 
 class StateMachine
 {
 private:
-    State current{Standby};
+    State state_{Standby};
 
-    static constexpr uint64_t maxFillTime_;
-    static constexpr uint64_t minEmptyTime_;
+    static constexpr uint64_t maxFillTime_{24000};
     uint64_t elapsedPump_; 
-    uint64_t elapsedLastFill_; 
+    uint64_t startPump_; 
 
     LevelSensor lowSensor_{LOW_LEVEL_PIN};
     LevelSensor highSensor_{HIGH_LEVEL_PIN};
@@ -55,21 +19,19 @@ private:
 
     bool checkFailures()
     {
-        // how long we've been pumping water
-        if (elampsedPump_ > maxFillTime_)
+        if (elampsedPump_ - startPump_ > maxFillTime_)
             return true;
 
-        // checking the sanity of our switch state
-
-        // bad state: any time the sensors above see something the sensors below do
-        // or the overflow sensor is on
+        // Sensor Sanity-Check
+        // **** bad state: any time the sensor above sees water while the lower
+        // **** sensor doesn't OR any time the overflow sensor detects water
         if (overflowSensor_.checkState() || (highSensor_.checkState() && !lowSensor_.checkState()))
             return true;
 
         return false;
     }
 public:
-    void update(uint64_t dt)
+    void update(uint64_t ts)
     {
         digitalRead(LOW_LEVEL_PIN);
 
@@ -81,35 +43,32 @@ public:
 
     void transition(State next)
     {
-        // on certain transitions we enable/disable stuff
-        auto prev = current;
+        auto from = state_;
 
         // transition functions
-        if (prev == States::Failure) //can't escape failure
+        if (from == States::Failure) //can't escape failure
             return;
-        else if (prev == States::Standby && next == States::Pump)
+        else if (from == States::Standby && next == States::Pump)
         {
-            elapsedPump_ = 0;
+            startPump_ = millis();
             digitalWrite(WATER_PUMP_PIN, FILL);
         }
-        else if (prev == States::Pump)
+        else if (from == States::Pump)
         {
-            elapsedLastFill_ = 0;
             digitalWrite(WATER_PUMP_PIN, STOP);
         }
-        current = dst;
+        state_ = dst;
     };
 
-    void stateop(uint64_t dt)
+    void stateop(uint64_t ts)
     {
-        switch(current)
+        switch(state_)
         {
             case States::Standby:
                 return;
             case States::Pump:
-                elapsedPump_ += dt;
-                // keep pumping,
-                // update dt for failsafes or something
+                elapsedPump_ = ts;
+                // update time pumped and keep pumping
                 return;
             case States::Failure:
                 // blink error light
@@ -118,15 +77,6 @@ public:
     };
 };
 
-
-// TODO: Abstract these guys away
-// TODO: Make state machine with debounce time for transitions
-// TODO: Make low-pass filter
-// TODO: Implement project well (good)
-constexpr unsigned DEBOUNCE_INTERVAL_MS 733;
-constexpr unsigned MAX_FLOW_TIME 24000;
-constexpr unsigned DEBOUNCE 500;
-
 unsigned int prev_time = 0;
 unsigned int curr_time = 0;
 unsigned int flow_time = 0;
@@ -135,23 +85,8 @@ void setup() {
   pinMode(TRIGGER_PIN,OUTPUT);
   pinMode(ECHO_PIN,INPUT);
   pinMode(RELAY_PIN,OUTPUT);
-  Serial.begin(9600);
 }
 void loop() {
   unsigned int now = millis();
   flow_time = millis() - prev_time;
-  Serial.print(distance);
-  Serial.println("cm");
-  if(debounce < DEBOUNCE_INTERVAL_MS)
-    return;
-  if(distance <= 10) {
-    //digitalWrite(RELAY_PIN,STOP);
-    Serial.println("STOP!");
-    flow_time = 0;    
-  }
-  if(distance >= 22 && now-prev_time < DEBOUNCE){ 
-    //digitalWrite(RELAY_PIN,FILL);
-    Serial.println("FILL!");
-    prev_time = millis();  
-  }                                                                                                        
 }

coffee-pins.hh

@@ -5,3 +5,37 @@ constexpr unsigned WATER_PUMP_PIN       = 5;
 
 constexpr unsigned FILL = HIGH;
 constexpr unsigned STOP = LOW;
+
+class LevelSensor
+{
+public:
+    LevelSensor(int pin) : sensePin_(pin) {}
+
+    bool checkState()
+    {
+        bool measured = digitalRead(sensePin_);
+        measured = failOpen_ ? !measured : measured;
+
+        uint64_t curTime = millis();
+
+        if (measured == curState_)
+        {
+            transitionTime = curTime;
+        }
+
+        if (curTime - transitionTime_ > debounceTime_)
+        {
+            transitionTime = curTime; 
+            curState_ = measured;
+        }
+
+        return curState_;
+    }
+
+private:
+    int sensePin_;
+    bool failOpen_;
+    uint64_t transitionTime_{0};
+    bool curState_{false};
+    static constexpr debounceTime_ {250}; // millis
+};