// Test for Discord channel.
// This is not working code ?
// Code from 4:08 AM
//
// A different rotary encoder might be used ?
// Wokwi has only one type of rotary encoder.
// CLK = A
// DT  = B

// Arduino Variable Power Station Code
// Components: Motor Driver, 0.91" I2C OLED Display, Rotary Encoder
// Voltage increments by 0.05V, click switches between Amps and Volts, double-click locks the selection with a lock symbol

#include <Wire.h>
#include <U8glib.h>

U8GLIB_SSD1306_128X32 u8g(U8G_I2C_OPT_NONE);

const int encoderPinA = 2;
const int encoderPinB = 3;
const int encoderSwitch = 4;
const int motorPWM = 5;

float voltage = 0.0;
float current = 0.0;
bool isLocked = false;
bool selectingVoltage = true;
bool lastButtonState = HIGH;
unsigned long lastButtonPress = 0;
unsigned long lastButtonRelease = 0;
bool singleClickDetected = false;
bool encoderMoved = false;
unsigned long lastUpdate = 0;
const int updateInterval = 2;  // Further slow down loop execution

void setup() {
  pinMode(encoderPinA, INPUT);
  pinMode(encoderPinB, INPUT);
  pinMode(encoderSwitch, INPUT_PULLUP);
  pinMode(motorPWM, OUTPUT);
  attachInterrupt(digitalPinToInterrupt(encoderPinA), onEncoderMove, CHANGE);
}

void loop() {
  if (millis() - lastUpdate > updateInterval) {
    handleButtonPress();
    if (encoderMoved && !isLocked) {
      updateValues();
      encoderMoved = false;
    }
    displayValues();
    analogWrite(motorPWM, (int)(voltage * 51));  // Scale 0-5V to 0-255
    lastUpdate = millis();
    delay(50);  // Added wait function to slow down loop execution
  }
}

void handleButtonPress() {
  bool buttonState = digitalRead(encoderSwitch);
  if (buttonState == LOW && lastButtonState == HIGH) {
    lastButtonPress = millis();
  } else if (buttonState == HIGH && lastButtonState == LOW) {
    lastButtonRelease = millis();
    if (lastButtonRelease - lastButtonPress < 300) {
      if (singleClickDetected && (millis() - lastButtonPress) < 600) {
        isLocked = !isLocked;  // Double-click: Lock/Unlock
        singleClickDetected = false;
      } else {
        singleClickDetected = true;
      }
    }
  }
  if (singleClickDetected && (millis() - lastButtonPress) > 600) {
    selectingVoltage = !selectingVoltage;  // Single click: Switch selection
    singleClickDetected = false;
  }
  lastButtonState = buttonState;
}

void onEncoderMove() {
  encoderMoved = true;
}

void updateValues() {
  int increment = digitalRead(encoderPinB) ? 2 : -2;  // Increased sensitivity

  if (selectingVoltage) {
    voltage = constrain(voltage + increment * 0.05, 0.0, 5.0);
  } else {
    current = constrain(current + increment * 0.01, 0.0, 2.0);
  }
}

void displayValues() {
  u8g.firstPage();
  do {
    u8g.setFont(u8g_font_ncenB08r);
    u8g.setPrintPos(0, 12);
    if (selectingVoltage) u8g.print('>');
    u8g.print("V: "); u8g.print(voltage, 2);
    u8g.setPrintPos(0, 28);
    if (!selectingVoltage) u8g.print('>');
    u8g.print("A: "); u8g.print(current, 2);
    if (isLocked) {
      // Draw pixel art lock symbol on the right side of the screen
      u8g.drawFrame(114, 2, 10, 12);  // Lock body
      u8g.drawBox(116, 0, 6, 4);      // Lock shackle
    }
  } while (u8g.nextPage());
}