#include <Servo.h>
int servoPin = 4;
int trigPin = 11;
int echoPin = 12;
long duration, cm;
int LED = 8;
int LEDR = 9;
int LEDG = 5;
int LEDB = 6;
int redVal = 255;
int greenVal = 0;
int blueVal = 0;
Servo Servo1;
int Buzzer = 7;

#ifndef MUSIC_H
#define MUSIC_H
// Define the pitches
#define G4 392
#define F4 349
#define E4 330
#define D4 294
#define C4 262
#define A4 440
#define C5 523
// Define the tempo values
#define T4 1.0
#define T8 0.5
#define T2 2.0
#define T4d 1.5 // dotted quarter note

// Define the songs using pitch and tempo constants
const int song1_pitch[] = {
    G4, E4, E4, 0, F4, D4, D4, 0, C4, D4, E4, F4, G4, G4, G4, 0
};
const float song1_tempo[] = {
    T4, T4, T4, T4, T4, T4, T4, T4, T4, T4, T4, T4, T4, T4, T4, T4
};

const int song2_pitch[] = {
    C4, C4, D4, E4, E4, D4, C4, D4, E4, C4, 0, E4, E4, F4, G4, G4, F4, E4, F4, G4, E4, 0
};
const float song2_tempo[] = {
    T4, T8, T8, T4, T4, T8, T8, T8, T8, T4, T4, T4, T8, T8, T4, T4, T8, T8, T8, T8, T4, T4
};

const int song3_pitch[] = {
    C4, C4, D4, F4, G4, F4, G4, A4, 0, C5, A4, A4, G4, F4, G4, 0, 0
};
const float song3_tempo[] = {
    T4d, T8, T4, T4, T4, T8, T8, T4, T4, T4d, T8, T8, T8, T4, T2, T4, T4
};
#endif

#define ButtonPin 10 //按鈕開關的接腳
#define SegmentPinStart 2 //七段顯示器開始的接腳

// 七段顯示器的位模式，每個元素表示一個數字的位狀態（abcdefg, dp）
const byte seg7_digit[6][8] = {
  {0, 0, 0, 0, 0, 0, 1, 1}, // 0.
  {1, 0, 0, 1, 1, 1, 1, 1}, // 1.
  {0, 0, 1, 0, 0, 1, 0, 1}, // 2.
  {0, 0, 0, 0, 1, 1, 0, 1}, // 3.
  {1, 0, 0, 1, 1, 0, 0, 1}, // 4.
  {0, 1, 0, 0, 1, 0, 0, 1}  // 5.
};


void setup() {
  Servo1.attach(servoPin);
  Serial.begin(9600);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(LEDR, OUTPUT);
  pinMode(LEDG, OUTPUT);
  pinMode(LEDB, OUTPUT);
  pinMode(LED, OUTPUT);
  pinMode(Buzzer, OUTPUT);
  pinMode(ButtonPin, INPUT_PULLUP); //設置按鈕接腳為輸入，啟用內部上拉電阻
  for (int i = SegmentPinStart; i < SegmentPinStart + 8; i++) {
    pinMode(i, OUTPUT); //設置七段顯示器的接腳為輸出
  }
}

void loop() {
  measureDistance();
  handleDistanceLogic();
}

void measureDistance() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(5);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  cm = (duration / 2) / 29.1;
  Serial.print(cm);
  Serial.println(" cm");
}

void handleDistanceLogic() {
  static int cycleCount = 0; // To track the number of cycles
  static int num = 0; // To store the displayed number

  if (cm >= 5 && cm <= 30) {
    if (cycleCount < 5) { // Limit to 5 cycles
      digitalWrite(LED, HIGH);
      Servo1.write(90);
      delay(3000);
      handleLEDEffects();
      handleBuzzer();
      showDigit(0); // Display "0." on the 7-segment display
      waitForButtonPress(num); // Wait for button press to increment number
      showDigit(num); // Display number on the 7-segment display
      delay(130);
      cycleCount++; // Increment the cycle count
    } else {
      digitalWrite(LED, LOW);
      Servo1.write(0);
      delay(1500);
    }
  } else if (cm > 30) {
    digitalWrite(LED, LOW);
    Servo1.write(0);
    delay(1500);
  }
}

void handleLEDEffects() {
  if (cm > 30) return; // 如果距離大於30cm，不會呼叫handleLEDEffects
  int delayTime = getLEDDuration();
  for (byte i = 0; i < 255; i++) {
    redVal--;
    greenVal++;
    analogWrite(LEDR, redVal);
    analogWrite(LEDG, greenVal);
    delay(delayTime);
  }
  for (byte i = 0; i < 255; i++) {
    greenVal--;
    blueVal++;
    analogWrite(LEDG, greenVal);
    analogWrite(LEDB, blueVal);
    delay(delayTime);
  }
  for (byte i = 0; i < 255; i++) {
    blueVal--;
    redVal++;
    analogWrite(LEDB, blueVal);
    analogWrite(LEDR, redVal);
    delay(delayTime);
  }
}

int getLEDDuration() {
  if (cm >= 5 && cm <= 10) return 1;
  else if (cm > 10 && cm <= 20) return 3;
  else if (cm > 20 && cm <= 30) return 5;
  return 5; // Default
}

void handleBuzzer() {
  showDigit(0); // Display "0." on the 7-segment display
  if (cm >= 5 && cm <= 10) playSong(0);
  else if (cm > 10 && cm <= 20) playSong(1);
  else if (cm > 20 && cm <= 30) playSong(2);
}

void playSong(int songIndex) {
  const int* pitch_ptr[] = {song1_pitch, song2_pitch, song3_pitch};
  const float* tempo_ptr[] = {song1_tempo, song2_tempo, song3_tempo};
  int speed[3] = {140, 80, 60};
  int T1time = 4 * 60000 / speed[songIndex];
  
  for (int i = 0; pitch_ptr[songIndex][i] != 0; i++) {
    int pitch = pitch_ptr[songIndex][i];
    float duration = T1time * tempo_ptr[songIndex][i];
    tone(Buzzer, pitch, duration / 2);
    delay(duration / 2);
  }
}

void waitForButtonPress(int &num) {
  while (digitalRead(ButtonPin) == HIGH); // Wait for button press
  delay(50); // Debounce delay
  if (digitalRead(ButtonPin) == LOW) { // Confirm button press
    num = (num + 1) % 6; // Increment number within 0 to 5
    delay(200); // Avoid multiple counts for one press
  }
}

void showDigit(int digit) {
  for (int i = 0; i < 8; i++) {
    digitalWrite(SegmentPinStart + i, seg7_digit[digit][i]); //根據位模式設置七段顯示器的接腳
  }
}