#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

#define OLED_RESET     -1 // Reset pin # (or -1 if sharing Arduino reset pin)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

#define TRIGGER_PIN 2 // Ultrasonic sensor trigger pin
#define ECHO_PIN 3 // Ultrasonic sensor echo pin
#define PUMP_PIN 7 // Pump control pin
#define MANUAL_SWITCH_PIN 4 // Manual mode switch pin
#define PUMP_TOGGLE_BUTTON_PIN 5 // Single button for pump toggle

#define WATER_LEVEL_THRESHOLD_LOW 10 // Low water level threshold for automatic mode
#define WATER_LEVEL_THRESHOLD_HIGH 90 // High water level threshold for automatic mode

int manualMode = 0; // 0: Auto mode, 1: Manual mode
int waterLevel = 0;
bool pumpState = false; // Pump initial state: OFF
bool lastPumpToggleState = LOW; // Last state of pump toggle button
bool lastManualModeState = LOW; // Last state of manual mode switch

void setup() {
  pinMode(PUMP_PIN, OUTPUT);
    pinMode(MANUAL_SWITCH_PIN, INPUT_PULLUP);
      pinMode(PUMP_TOGGLE_BUTTON_PIN, INPUT);

        Serial.begin(9600);

          if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
              Serial.println(F("SSD1306 allocation failed"));
                  for(;;);
                    }
                      display.display();
                        display.clearDisplay();
                          display.setTextSize(1);
                            display.setTextColor(WHITE);

                              pinMode(TRIGGER_PIN, OUTPUT);
                                pinMode(ECHO_PIN, INPUT);
                                }

                                void loop() {
                                  int currentManualModeState = digitalRead(MANUAL_SWITCH_PIN);
                                    if (currentManualModeState != lastManualModeState) {
                                        delay(50); // Debounce delay
                                            lastManualModeState = currentManualModeState;
                                              }
                                                
                                                  if(currentManualModeState == LOW) {
                                                      manualMode = 0; // Auto mode
                                                          waterLevel = getWaterLevel();
                                                              
                                                                  if(waterLevel < WATER_LEVEL_THRESHOLD_LOW) {
                                                                        pumpState = true; // Turn on pump
                                                                            } else if(waterLevel > WATER_LEVEL_THRESHOLD_HIGH) {
                                                                                  pumpState = false; // Turn off pump
                                                                                      }
                                                                                        } else {
                                                                                            manualMode = 1; // Manual mode
                                                                                                
                                                                                                    waterLevel = getWaterLevel(); // Update water level in manual mode
                                                                                                        
                                                                                                            int currentPumpToggleState = digitalRead(PUMP_TOGGLE_BUTTON_PIN);
                                                                                                                if (currentPumpToggleState != lastPumpToggleState) {
                                                                                                                      delay(50); // Debounce delay
                                                                                                                            lastPumpToggleState = currentPumpToggleState;
                                                                                                                                  
                                                                                                                                        if(currentPumpToggleState == HIGH) {
                                                                                                                                                pumpState = !pumpState; // Toggle pump state
                                                                                                                                                      }
                                                                                                                                                          }
                                                                                                                                                              
                                                                                                                                                                  if(waterLevel >= WATER_LEVEL_THRESHOLD_HIGH) {
                                                                                                                                                                        pumpState = false; // Turn off pump when tank is full
                                                                                                                                                                            }
                                                                                                                                                                              }

                                                                                                                                                                                digitalWrite(PUMP_PIN, pumpState); // Control pump based on pumpState
                                                                                                                                                                                  
                                                                                                                                                                                    display.clearDisplay(); 
                                                                                                                                                                                      display.setCursor(0, 0);
                                                                                                                                                                                        display.println("Water Level:");
                                                                                                                                                                                          display.print(waterLevel);
                                                                                                                                                                                            display.println("%");

                                                                                                                                                                                              display.setCursor(0, 20);
                                                                                                                                                                                                display.print("Pump: ");
                                                                                                                                                                                                  if(pumpState) {
                                                                                                                                                                                                      display.println("ON");
                                                                                                                                                                                                        } else {
                                                                                                                                                                                                            display.println("OFF");
                                                                                                                                                                                                              }

                                                                                                                                                                                                                display.setCursor(0, 34);
                                                                                                                                                                                                                  display.print("Mode: ");
                                                                                                                                                                                                                    if(manualMode == 0) {
                                                                                                                                                                                                                        display.println("Auto");
                                                                                                                                                                                                                          } else {
                                                                                                                                                                                                                              display.println("Manual");
                                                                                                                                                                                                                                }

                                                                                                                                                                                                                                  // Draw a simple tank image
                                                                                                                                                                                                                                    drawTankImage(85, 23, 40, waterLevel);

                                                                                                                                                                                                                                      display.display();

                                                                                                                                                                                                                                        delay(1000); // Add a delay to avoid flickering
                                                                                                                                                                                                                                        }

                                                                                                                                                                                                                                        int getWaterLevel() {
                                                                                                                                                                                                                                          long duration, distance;
                                                                                                                                                                                                                                            
                                                                                                                                                                                                                                              digitalWrite(TRIGGER_PIN, LOW);
                                                                                                                                                                                                                                                delayMicroseconds(2);
                                                                                                                                                                                                                                                  digitalWrite(TRIGGER_PIN, HIGH);
                                                                                                                                                                                                                                                    delayMicroseconds(10);
                                                                                                                                                                                                                                                      digitalWrite(TRIGGER_PIN, LOW);
                                                                                                                                                                                                                                                        
                                                                                                                                                                                                                                                          duration = pulseIn(ECHO_PIN, HIGH);
                                                                                                                                                                                                                                                            distance = duration * 0.034 / 8; // Calculate distance in cm
                                                                                                                                                                                                                                                              
                                                                                                                                                                                                                                                                int level = map(distance, 0, 100, 100, 0); // Map distance to water level percentage
                                                                                                                                                                                                                                                                  
                                                                                                                                                                                                                                                                    return constrain(level, 0, 100); // Ensure water level is within 0-100 range
                                                                                                                                                                                                                                                                    }

                                                                                                                                                                                                                                                                    void drawTankImage(int x, int y, int width, int waterLevel) {
                                                                                                                                                                                                                                                                      // Draw tank outline
                                                                                                                                                                                                                                                                        display.drawRect(x, y, width, 40, WHITE);
                                                                                                                                                                                                                                                                          display.drawRect(x + 2, y + 2, width - 4, 36, WHITE);

                                                                                                                                                                                                                                                                            // Calculate the tank fill level based on waterLevel
                                                                                                                                                                                                                                                                              int tankFillHeight = map(waterLevel, 0, 100, 2, 36);
                                                                                                                                                                                                                                                                                
                                                                                                                                                                                                                                                                                  // Draw tank fill based on water level
                                                                                                                                                                                                                                                                                    display.fillRect(x + 4, y + 38 - tankFillHeight, width - 8, tankFillHeight, WHITE);
                                                                                                                                                                                                                                                                                    }