#include <SevSeg.h>
SevSeg sevseg;

// Pin Definitions
const int button1Pin = 2;   // Increase time / Next company-unit
const int button2Pin = 3;   // Decrease time / Previous company-unit
const int button3Pin = 5;   // Start/Stop / Confirm / Exit mode
const int button4Pin = 4;   // Toggle speed / Enter-exit mode
const int latchPin = 8;     // 74HC595 latch
const int clockPin = 7;     // 74HC595 clock
const int dataPin = 9;      // 74HC595 data
const int relaySpeedPin = A5; // Speed relay (off=H, on=L)
const int relayMotorPin = 6;  // Motor relay

// Common Anode Display Patterns (inverted for active-low)
const byte letterL = ~0b00001110; // L
const byte letterH = ~0b00110111; // H
const byte letterU = ~0b00111110; // U
const byte digit1 = ~0b00110000;  // 1
const byte digit2 = ~0b01101101;  // 2
const byte digit3 = ~0b01111001;  // 3
const byte digit5 = ~0b01011011;  // 5
const byte blankPattern = ~0b00000000; // Blank

// Category Selection Settings
#define NUM_COMPANIES 4
#define NUM_UNITS 4
const char* companyCodes[NUM_COMPANIES] = {"CL", "SP", "OY", "CS"}; // Sina Lux, Sepehr, Yottaly, Cina Silver
const byte unitCodes[NUM_UNITS] = {digit1, digit2, digit3, digit5};
const int units[NUM_UNITS] = {1, 2, 3, 5};
// Settings: [company][unit] = {time, isLowSpeed}
const byte settings[NUM_COMPANIES][NUM_UNITS][2] = {
  // Sina Lux (CL)
  {{20, 0}, {25, 0}, {30, 0}, {40, 1}}, // 1: 20s H, 2: 25s H, 3: 30s H, 5: 40s L
  // Sepehr (SP)
  {{15, 0}, {20, 0}, {25, 1}, {35, 1}}, // 1: 15s H, 2: 20s H, 3: 25s L, 5: 35s L
  // Yottaly (OY)
  {{10, 0}, {15, 0}, {20, 1}, {30, 1}}, // 1: 10s H, 2: 15s H, 3: 20s L, 5: 30s L
  // Cina Silver (CS)
  {{25, 0}, {30, 0}, {35, 0}, {45, 1}}  // 1: 25s H, 2: 30s H, 3: 35s H, 5: 45s L
};

// Variables
int currentNumber = 0;           // Current time setting (0-99)
int entryNumber = 0;             // Time at mode entry
bool countingDown = false;       // Mixing state
bool isLowSpeed = false;         // false: H (high), true: L (low)
bool entrySpeed = false;         // Speed at mode entry
bool categoryMode = false;       // Category selection mode
bool showSC = false;             // Show flashing "SC"
bool showUnit = false;           // Show flashing "U" or unit
bool unitConfirmed = false;      // Unit confirmed, allow adjust
bool optionsLocked = false;      // Company and unit locked display
bool unitNavigationStarted = false; // Unit navigation started
bool firstUnitPress = true;      // Track first Button 1 press
int selectedCompany = 0;         // Current company index (0-3)
int selectedUnit = 0;            // Current unit index (0-3)
unsigned long lastButtonPressTime = 0;
const unsigned long debounceDelay = 200; // Debounce for all buttons
unsigned long previousMillis = 0; // For countdown timing
int lastSetTime = 0;             // Original time set at cycle start
bool lastSpeedWasLow = false;    // Original speed set at cycle start
static int lastButton3State = HIGH; // Last state of Button 3
static int lastButton4State = HIGH; // Last state of Button 4
static unsigned long button3PressStart = 0; // Time when Button 3 is pressed
static unsigned long button4PressStart = 0; // Time when Button 4 is pressed
static bool button3HeldForExit = false; // Flag for 3s hold
static bool button4HeldForMode = false; // Flag for 3s hold
static unsigned long lastFlashTime = 0; // For "SC"/"U"/unit flashing
const unsigned long flashInterval = 500; // Flash every 500ms
static bool flashOn = false;     // Flash state

void setup() {
  // Initialize seven-segment displays
  byte numDigits = 2;
  byte digitPins[] = {A3, A4};
  byte segmentPins[] = {10, 11, 12, 13, A0, A1, A2};
  sevseg.begin(COMMON_CATHODE, numDigits, digitPins, segmentPins);
  sevseg.setBrightness(90); // Adjust if needed
  
  // Initialize pins
  pinMode(button1Pin, INPUT_PULLUP);
  pinMode(button2Pin, INPUT_PULLUP);
  pinMode(button3Pin, INPUT_PULLUP);
  pinMode(button4Pin, INPUT_PULLUP);
  pinMode(latchPin, OUTPUT);
  pinMode(clockPin, OUTPUT);
  pinMode(dataPin, OUTPUT);
  pinMode(relayMotorPin, OUTPUT);
  pinMode(relaySpeedPin, OUTPUT);
  
  // Initial relay state (active-low: LOW = on, HIGH = off)
  digitalWrite(relayMotorPin, HIGH); // Motor off
  digitalWrite(relaySpeedPin, LOW); // Speed high (H, relay on)
  
  // Initial display
  char displayStr[3];
  sprintf(displayStr, "%02d", currentNumber);
  sevseg.setChars(displayStr);
  displayPattern(letterH);
}

void loop() {
  unsigned long currentMillis = millis();
  
  // Handle Button 4: Detect 3s hold for mode or short press for speed
  int button4State = digitalRead(button4Pin);
  if (button4State == LOW &&  lastButton4State == HIGH) {
    button4PressStart = currentMillis;
    button4HeldForMode = false;
  } else if (button4State == LOW && currentMillis - button4PressStart >= 3000 && !button4HeldForMode) {
    // 3s hold detected
    if (!countingDown) {
      categoryMode = !categoryMode;
      button4HeldForMode = true;
      lastButtonPressTime = currentMillis;
      if (categoryMode) {
        // Enter mode: Save settings, blank displays for 500ms
        entryNumber = currentNumber;
        entrySpeed = isLowSpeed;
        sevseg.blank();
        displayPattern(blankPattern);
        delay(500);
        showSC = true;
        showUnit = false;
        unitConfirmed = false;
        optionsLocked = false;
        unitNavigationStarted = false;
        firstUnitPress = true;
        selectedCompany = 0;
        selectedUnit = 0;
        flashOn = true;
      } else {
        // Exit mode: Restore settings
        showSC = false;
        showUnit = false;
        unitConfirmed = false;
        optionsLocked = false;
        unitNavigationStarted = false;
        firstUnitPress = true;
        currentNumber = entryNumber;
        isLowSpeed = entrySpeed;
        char displayStr[3];
        sprintf(displayStr, "%02d", currentNumber);
        sevseg.setChars(displayStr);
        displayPattern(isLowSpeed ? letterL : letterH);
        digitalWrite(relaySpeedPin, isLowSpeed ? HIGH : LOW); // H: on, L: off
      }
    }
  } else if (button4State == HIGH && lastButton4State == LOW && !button4HeldForMode && currentMillis - lastButtonPressTime > debounceDelay && !countingDown) {
    // Short press: Toggle speed in normal mode or category mode after unit confirm, before lock
    isLowSpeed = !isLowSpeed;
    displayPattern(isLowSpeed ? letterL : letterH);
    digitalWrite(relaySpeedPin, isLowSpeed ? HIGH : LOW); // H: on, L: off
    lastButtonPressTime = currentMillis;
  }
  lastButton4State = button4State;
  
  // Handle Button 3: Short press for confirm, 3s hold to exit, or start/stop
  int button3State = digitalRead(button3Pin);
  if (button3State == LOW && lastButton3State == HIGH) {
    button3PressStart = currentMillis;
    button3HeldForExit = false;
  } else if (button3State == LOW && currentMillis - button3PressStart >= 3000 && !button3HeldForExit && categoryMode) {
    // 3s hold: Exit category mode
    categoryMode = false;
    showSC = false;
    showUnit = false;
    unitConfirmed = false;
    optionsLocked = false;
    unitNavigationStarted = false;
    firstUnitPress = true;
    currentNumber = entryNumber;
    isLowSpeed = entrySpeed;
    char displayStr[3];
    sprintf(displayStr, "%02d", currentNumber);
    sevseg.setChars(displayStr);
    displayPattern(isLowSpeed ? letterL : letterH);
    digitalWrite(relaySpeedPin, isLowSpeed ? HIGH : LOW); // H: on, L: off
    button3HeldForExit = true;
    lastButtonPressTime = currentMillis;
  } else if (button3State == HIGH && lastButton3State == LOW && !button3HeldForExit && currentMillis - lastButtonPressTime > debounceDelay && categoryMode) {
    // Short press: Confirm
    if (!showSC && !showUnit) {
      // Confirm company
      showUnit = true;
      lastFlashTime = currentMillis;
      flashOn = true;
      selectedUnit = 0;
      unitNavigationStarted = false;
      firstUnitPress = true;
    } else if (showUnit && !unitConfirmed) {
      // Confirm unit, lock company and unit display
      unitConfirmed = true;
      optionsLocked = true;
      unitNavigationStarted = false;
      firstUnitPress = true;
      currentNumber = settings[selectedCompany][selectedUnit][0];
      isLowSpeed = settings[selectedCompany][selectedUnit][1];
      sevseg.setChars(companyCodes[selectedCompany]);
      displayPattern(unitCodes[selectedUnit]);
    } else if (unitConfirmed && optionsLocked) {
      // Second confirm: Show time and speed
      optionsLocked = false;
      char displayStr[3];
      sprintf(displayStr, "%02d", currentNumber);
      sevseg.setChars(displayStr);
      displayPattern(isLowSpeed ? letterL : letterH);
      digitalWrite(relaySpeedPin, isLowSpeed ? HIGH : LOW); // H: on, L: off
    } else if (unitConfirmed && !optionsLocked) {
      // Final confirm: Start countdown
      categoryMode = false;
      showSC = false;
      showUnit = false;
      unitConfirmed = false;
      optionsLocked = false;
      unitNavigationStarted = false;
      firstUnitPress = true;
      countingDown = true;
      if (lastSetTime == 0) {
        lastSetTime = currentNumber; // Store initial time
        lastSpeedWasLow = isLowSpeed; // Store initial speed
      }
      previousMillis = currentMillis;
      digitalWrite(relayMotorPin, LOW); // Start motor
      digitalWrite(relaySpeedPin, isLowSpeed ? HIGH : LOW); // H: on, L: off
    }
    lastButtonPressTime = currentMillis;
  } else if (button3State == HIGH && lastButton3State == LOW && !button3HeldForExit && currentMillis - lastButtonPressTime > debounceDelay && !categoryMode) {
    // Short press: Start/Stop countdown
    if (!countingDown && currentNumber > 0) {
      countingDown = true;
      if (lastSetTime == 0) {
        lastSetTime = currentNumber; // Store initial time
        lastSpeedWasLow = isLowSpeed; // Store initial speed
      }
      previousMillis = currentMillis;
      digitalWrite(relayMotorPin, LOW); // Start motor
      digitalWrite(relaySpeedPin, isLowSpeed ? HIGH : LOW); // H: on, L: off
    } else if (countingDown) {
      countingDown = false;
      digitalWrite(relayMotorPin, HIGH); // Stop motor
      digitalWrite(relaySpeedPin, isLowSpeed ? HIGH : LOW); // Maintain current speed
      char displayStr[3];
      sprintf(displayStr, "%02d", currentNumber);
      sevseg.setChars(displayStr);
      displayPattern(isLowSpeed ? letterL : letterH);
    }
    lastButtonPressTime = currentMillis;
  }
  lastButton3State = button3State;
  
  // Handle category selection mode
  if (categoryMode) {
    // Flashing display
    if (currentMillis - lastFlashTime >= flashInterval && (!unitConfirmed || !optionsLocked)) {
      lastFlashTime = currentMillis;
      flashOn = !flashOn;
    }
    char displayStr[3];
    if (showSC) {
      // Flash "SC"
      if (flashOn) {
        sevseg.setChars("SC");
      } else {
        sevseg.blank();
      }
      displayPattern(blankPattern);
    } else if (showUnit && !unitConfirmed) {
      // Flash "U" or unit
      if (flashOn) {
        displayPattern(unitNavigationStarted ? unitCodes[selectedUnit] : letterU);
      } else {
        displayPattern(blankPattern);
      }
      sevseg.setChars(companyCodes[selectedCompany]);
    } else if (unitConfirmed && optionsLocked) {
      // Show locked company and unit
      sevseg.setChars(companyCodes[selectedCompany]);
      displayPattern(unitCodes[selectedUnit]);
    } else if (unitConfirmed && !optionsLocked) {
      // Show time and speed
      sprintf(displayStr, "%02d", currentNumber);
      sevseg.setChars(displayStr);
      displayPattern(isLowSpeed ? letterL : letterH);
    } else {
      // Show company
      sevseg.setChars(companyCodes[selectedCompany]);
      displayPattern(blankPattern);
    }
    
    // Navigation and adjustments
    if (digitalRead(button1Pin) == LOW && currentMillis - lastButtonPressTime > debounceDelay) {
      if (showSC) {
        showSC = false;
        selectedCompany = 0;
      } else if (!showUnit && selectedCompany < NUM_COMPANIES - 1) {
        selectedCompany++;
      } else if (showUnit && !unitConfirmed) {
        unitNavigationStarted = true;
        if (!firstUnitPress && selectedUnit < NUM_UNITS - 1) {
          selectedUnit++;
        }
        firstUnitPress = false;
      } else if (unitConfirmed && !optionsLocked) {
        // Adjust time
        currentNumber = min(99, currentNumber + 1);
        sprintf(displayStr, "%02d", currentNumber);
        sevseg.setChars(displayStr);
      }
      lastButtonPressTime = currentMillis;
    }
    if (digitalRead(button2Pin) == LOW && currentMillis - lastButtonPressTime > debounceDelay) {
      if (showSC) {
        showSC = false;
        selectedCompany = 0;
      } else if (!showUnit && selectedCompany > 0) {
        selectedCompany--;
      } else if (showUnit && !unitConfirmed) {
        unitNavigationStarted = true;
        if (selectedUnit > 0) {
          selectedUnit--;
          firstUnitPress = false;
        }
      } else if (unitConfirmed && !optionsLocked) {
        // Adjust time
        currentNumber = max(0, currentNumber - 1);
        sprintf(displayStr, "%02d", currentNumber);
        sevseg.setChars(displayStr);
      }
      lastButtonPressTime = currentMillis;
    }
  } else {
    // Normal mode
    if (!countingDown) {
      // Adjust time in normal mode or when stopped
      if (digitalRead(button1Pin) == LOW && currentMillis - lastButtonPressTime > debounceDelay) {
        currentNumber = min(99, currentNumber + 1);
        char displayStr[3];
        sprintf(displayStr, "%02d", currentNumber);
        sevseg.setChars(displayStr);
        lastButtonPressTime = currentMillis;
      }
      if (digitalRead(button2Pin) == LOW && currentMillis - lastButtonPressTime > debounceDelay) {
        currentNumber = max(0, currentNumber - 1);
        char displayStr[3];
        sprintf(displayStr, "%02d", currentNumber);
        sevseg.setChars(displayStr);
        lastButtonPressTime = currentMillis;
      }
    }
    
    // Update countdown
    if (countingDown) {
      if (currentMillis - previousMillis >= 1000) {
        previousMillis = currentMillis;
        if (currentNumber > 0) {
          currentNumber--;
          char displayStr[3];
          sprintf(displayStr, "%02d", currentNumber);
          sevseg.setChars(displayStr);
        } else {
          countingDown = false;
          digitalWrite(relayMotorPin, HIGH); // Stop motor
          digitalWrite(relaySpeedPin, isLowSpeed ? HIGH : LOW); // Restore speed
          currentNumber = lastSetTime; // Restore initial time
          isLowSpeed = lastSpeedWasLow; // Restore initial speed
          char displayStr[3];
          sprintf(displayStr, "%02d", currentNumber);
          sevseg.setChars(displayStr);
          displayPattern(isLowSpeed ? letterL : letterH);
          digitalWrite(relaySpeedPin, isLowSpeed ? HIGH : LOW); // H: on, L: off
          lastSetTime = 0; // Clear for next cycle
        }
      }
    } else {
      // Update display in normal mode
      char displayStr[3];
      sprintf(displayStr, "%02d", currentNumber);
      sevseg.setChars(displayStr);
      displayPattern(isLowSpeed ? letterL : letterH);
      digitalWrite(relayMotorPin, HIGH); // Ensure motor off
    }
  }
  
  sevseg.refreshDisplay();
}

void displayPattern(byte pattern) {
  digitalWrite(latchPin, LOW);
  shiftOut(dataPin, clockPin, LSBFIRST, pattern);
  digitalWrite(latchPin, HIGH);
}