// TM1637 SevenSegment Counter Wokwi Example
//
// https://wokwi.com/projects/339227323398095442

#include <TM1637.h>
#include "pitches.h"
#include <math.h>

TM1637 tm(2, 3);

const int btn_set_timers[4] = {300, 1800, 7200};
const int btn_set_pins[4] = {5, 6, 7};

const int btn_mode = 4;
const int DEBOUNCE_DELAY = 50;
int lastSteadyState = HIGH;       // the previous steady state from the input pin
int lastFlickerableState = HIGH;  // the previous flickerable state from the input pin
int currentState;                // the current reading from the input pin
unsigned long lastDebounceTime = 0;  // the last time the output pin was toggled

int pot_pins[4] = {A0, A1, A2, A3};


void setup() {
  tm.init();
  tm.set(BRIGHT_TYPICAL);
  for (byte i = 0; i < 3; i = i + 1) {
    pinMode(btn_set_pins[i], INPUT_PULLUP);
  }
  pinMode(btn_mode, INPUT_PULLUP);
  for (byte i = 0; i < 4; i = i + 1) {
    pinMode(pot_pins[i], INPUT);
  }
  Serial.begin(9600);
  noTone(8);
}

int seconds_left = 0;
static unsigned long timer = millis();
int mode = 0;
// 0     init
// 1     timer
// 2     set time from pot
// 3     beep

int lcd_show_int(int value) {
  tm.display(0, (value / 1000) % 10);
  tm.display(1, (value / 100) % 10);
  tm.display(2, (value / 10) % 10);
  tm.display(3, value % 10);
  return 0;
}

void loop() {

  if (mode==0) {
    mode = 1;
    seconds_left = 9999;
    lcd_show_int(seconds_left);
    timer = millis();

  } else if (mode==1) {
      if (millis() - timer >= 1000) {
        if (seconds_left > 0) {
          seconds_left -= 1;
          lcd_show_int(seconds_left);
        } else {
          mode = 3;
        }
        timer += 1000;        
        
      }
  } else if (mode == 3) {
    tone(8, NOTE_D5);
    delay(300);
    noTone(8);
    delay(600);

  } else if (mode==2) {
    int pot_value = 0;
    for (byte i = 0; i < 4; i = i + 1) {
      int value = analogRead( pot_pins[i] );
      value =  (int) round (10 * value/1024);
      pot_value = pot_value + value * pow(10,i);
    }
    seconds_left = pot_value;
    lcd_show_int(seconds_left);
  }
  
  currentState = digitalRead( btn_mode );
  if (currentState != lastFlickerableState) {
    lastDebounceTime = millis();
    lastFlickerableState = currentState;
  }
  if ((millis() - lastDebounceTime) > DEBOUNCE_DELAY) {
    if (lastSteadyState == LOW && currentState == HIGH) {
      if (mode != 2 ) {
        mode=2;
      } else {
        mode = 1;
        timer = millis();

      }
    }
    lastSteadyState = currentState;
  }


  for (byte i = 0; i < 3; i = i + 1) {
    int value = digitalRead( btn_set_pins[i] );
    if ( value == LOW ) {
      mode = 1;
      seconds_left = btn_set_timers[i];
      lcd_show_int(seconds_left);
      timer = millis();
      
    }
  }

  


}