/*
 ==================================================
 Tank + Pump Simulator (Single Arduino - Wokwi)
 ==================================================
 Concept/Idea: N. M. D. Weerasinghe @ COTM
 Sketch Created: with ChatGPT (GPT-5) on 2025-08-24
 ==================================================

 Tank Level: 0-100
 Virtual Sensors (LED outputs):
   Pin 8  = HL  (>75)
   Pin 9  = HHL (>90)
   Pin 10 = OF  (>=98)
   Pin 11 = LL  (<25)
   Pin 12 = LLL (<10)
   Pin 13 = CL  (<3)

 Pump states:
   Pin 7  = Pump command (controller)
   Pin 6  = Pump running LED (green)
   Pin A0 = Pump Fault switch (red button, HIGH = fault)
   Pin A1 = Pump Force ON switch (yellow button, HIGH = force pump ON)
   Pin A2 = Consumption switch (blue button, HIGH = consumption enabled)
 ==================================================
*/

int pumpCommand = 7;   // Student controls pump here
int pumpLED     = 6;   // Green LED showing pump actually running

// Internal tank simulator variables
int tank_level = 0;
unsigned long lastPumpMillis = 0;
unsigned long lastUseMillis  = 0;

// Sensor pins (output to "virtual environment")
int HL  = 8;
int HHL = 9;
int OF  = 10;
int LL  = 11;
int LLL = 12;
int CL  = 13;

// Control switches
int swFault    = A0;  // Pump fault
int swForceOn  = A1;  // Force pump on
int swConsume  = A2;  // Toggle consumption

// Status flags
bool consumptionEnabled = true;

void setup() {
  // Pump
  pinMode(pumpCommand, OUTPUT);
  digitalWrite(pumpCommand, LOW);
  pinMode(pumpLED, OUTPUT);

  // Sensors
  pinMode(HL, OUTPUT);
  pinMode(HHL, OUTPUT);
  pinMode(OF, OUTPUT);
  pinMode(LL, OUTPUT);
  pinMode(LLL, OUTPUT);
  pinMode(CL, OUTPUT);

  // Switches
  pinMode(swFault, INPUT_PULLUP);
  pinMode(swForceOn, INPUT_PULLUP);
  pinMode(swConsume, INPUT_PULLUP);

  Serial.begin(9600);
  Serial.println("Tank + Pump Simulator Ready");
}

void loop() {
  unsigned long now = millis();

  // === External switches ===
  bool faultActive   = (digitalRead(swFault) == LOW);   // pressed = fault
  bool forceOnActive = (digitalRead(swForceOn) == LOW); // pressed = force pump
  consumptionEnabled = (digitalRead(swConsume) == LOW); // pressed = consume

  // === Determine pump running state ===
  bool pumpRunning = false;

  if (forceOnActive) {
    pumpRunning = true; // override controller
  } else if (faultActive) {
    pumpRunning = false; // pump fault, ignore controller
  } else {
    pumpRunning = (digitalRead(pumpCommand) == HIGH);
  }

  digitalWrite(pumpLED, pumpRunning);

  // === Tank filling (depends on pump running) ===
  if (pumpRunning) {
    if (now - lastPumpMillis >= 500) {   // every 0.5s
      lastPumpMillis = now;
      if (tank_level < 100) tank_level++;
    }
  }

  // === Tank consumption (independent) ===
  if (consumptionEnabled) {
    if (now - lastUseMillis >= 1000) {   // every 1s
      lastUseMillis = now;
      if (tank_level > 0) tank_level--;
    }
  }

  // === Update sensor outputs ===
  digitalWrite(HL,  (tank_level > 75));
  digitalWrite(HHL, (tank_level > 90));
  digitalWrite(OF,  (tank_level >= 98));
  digitalWrite(LL,  (tank_level < 25));
  digitalWrite(LLL, (tank_level < 10));
  digitalWrite(CL,  (tank_level < 3));

  // ==================================================
  // 🚧 STUDENT PUMP CONTROLLER LOGIC STARTS HERE 🚧
  // Example (replace with student logic):
  if (digitalRead(LL) == HIGH) {
    digitalWrite(pumpCommand, HIGH); // turn ON pump
  }
  if (digitalRead(HL) == HIGH) {
    digitalWrite(pumpCommand, LOW);  // turn OFF pump
  }
  // 🚧 STUDENT SECTION ENDS 🚧
  // ==================================================

  // === Debug Print ===
  Serial.print("Tank=");
  Serial.print(tank_level);

  Serial.print(" | HL=");  Serial.print(digitalRead(HL));
  Serial.print(" HHL=");  Serial.print(digitalRead(HHL));
  Serial.print(" OF=");   Serial.print(digitalRead(OF));
  Serial.print(" LL=");   Serial.print(digitalRead(LL));
  Serial.print(" LLL=");  Serial.print(digitalRead(LLL));
  Serial.print(" CL=");   Serial.print(digitalRead(CL));

  Serial.print(" | PumpCmd="); Serial.print(digitalRead(pumpCommand));
  Serial.print(" ForceOn=");  Serial.print(forceOnActive);
  Serial.print(" Fault=");    Serial.print(faultActive);
  Serial.print(" Consume=");  Serial.print(consumptionEnabled);

  Serial.print(" | PumpRunning=");
  Serial.println(pumpRunning);

  delay(100);
}