#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <Keypad.h>
#include <RTClib.h>

// RTC模块
RTC_DS1307 rtc;

// I2C LCD 配置（常见地址 0x27，显示 16x2）
LiquidCrystal_I2C lcd(0x27, 16, 2);

// 键盘配置
const byte ROWS = 4;
const byte COLS = 4;
char keys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};
byte rowPins[ROWS] = {9,8,7,6};
byte colPins[COLS] = {5,4,3,2};
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

// 提醒设备引脚
const int buzzerPin = A3;
const int ledPin = A4;

// 闹钟结构体
struct Alarm {
  byte hour;
  byte minute;
};
Alarm alarms[8][5];       // 每个隔间最多5个提醒
byte alarmCount[8] = {0};

unsigned long lastRefresh = 0;
bool isSetting = false;
bool isDeleting = false;
bool isViewingAlarms = false;

// 前置声明
void displayCurrentTime();
void displayAlarms();
void setAlarmProcess();
void deleteAlarm();
void checkMedicationTime();
void alertMedication(byte compartment);

// 主循环
void setup() {
  Wire.begin();                  // 初始化 I2C 总线
  pinMode(buzzerPin, OUTPUT);
  pinMode(ledPin, OUTPUT);
  digitalWrite(ledPin, LOW);

  lcd.init();                    // 初始化 LCD
  lcd.backlight();               // 打开背光

  Serial.begin(9600);
  if (!rtc.begin()) {
    lcd.clear();
    lcd.print("RTC failed!");
    while (1);
  }

  lcd.clear();
  lcd.print("Ready For Set");
  delay(1500);
  lcd.clear();
}

void loop() {
  // 如果在设置、删除、查看闹钟流程内，只允许流程自己控制 LCD，主界面不做刷新
  if (isSetting || isDeleting || isViewingAlarms) {
    checkMedicationTime(); // 只允许闹钟提醒
    return;
  }

  // 主界面刷新
  if (millis() - lastRefresh > 500) {
    displayCurrentTime();
    lastRefresh = millis();
  }

  char key = keypad.getKey();
  if (key == 'A') {
    isSetting = true;
    setAlarmProcess();
    isSetting = false;
  } else if (key == '*') {
    isDeleting = true;
    deleteAlarm();
    isDeleting = false;
  } else if (key == 'B') {
    isViewingAlarms = true;
    displayAlarms();
    isViewingAlarms = false;
  }
  checkMedicationTime();
}

// 1. 显示当前时间和主界面
void displayCurrentTime() {
  DateTime now = rtc.now();
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("Time:");
  if (now.hour() < 10) lcd.print('0');
  lcd.print(now.hour());
  lcd.print(":");
  if (now.minute() < 10) lcd.print('0');
  lcd.print(now.minute());
  lcd.print(":");
  if (now.second() < 10) lcd.print('0');
  lcd.print(now.second());

  lcd.setCursor(0,1);
  lcd.print("A:Set *:Del B:Show");
}

// 2. 设置提醒流程
void setAlarmProcess() {
  lcd.clear();
  lcd.print("Box(1-8)?:");
  byte compartment = 0xFF;
  while (true) {
    char key = keypad.getKey();
    if (key >= '1' && key <= '8') {
      compartment = key - '1';
      break;
    }
    if (key == 'D') {
      lcd.clear(); lcd.print("Canceled"); delay(800); return;
    }
  }

  lcd.clear(); lcd.print("Box"); lcd.print(compartment+1); lcd.print(":HHMM");
  char inputTime[5] = "";
  byte pos = 0;
  lcd.setCursor(0,1);

  while (pos < 4) {
    char key = keypad.getKey();
    if (key) {
      if (isDigit(key)) {
        inputTime[pos++] = key;
        lcd.print(key);
        if (pos == 2) lcd.print(":");
      } else if (key == '#') {
        if (pos > 0) {
          pos--; inputTime[pos] = 0;
          lcd.setCursor(pos + (pos >= 2 ? 1 : 0), 1);
          lcd.print(' ');
          lcd.setCursor(pos + (pos >= 2 ? 1 : 0), 1);
        }
      } else if (key == 'D') {
        lcd.clear(); lcd.print("Cancel"); delay(800); return;
      }
    }
  }

  byte hour = (inputTime[0]-'0')*10 + (inputTime[1]-'0');
  byte minute = (inputTime[2]-'0')*10 + (inputTime[3]-'0');

  if (hour < 24 && minute < 60) {
    if (alarmCount[compartment] < 5) {
      alarms[compartment][alarmCount[compartment]].hour = hour;
      alarms[compartment][alarmCount[compartment]].minute = minute;
      alarmCount[compartment]++;
      lcd.clear(); lcd.print("Set OK!"); delay(1000);
    } else {
      lcd.clear(); lcd.print("Max 5 alarms"); delay(1000);
    }
  } else {
    lcd.clear(); lcd.print("Invalid Time"); delay(1000);
  }
}

// 3. 删除提醒功能
void deleteAlarm() {
  lcd.clear(); lcd.print("Del Box(1-8)?");
  byte compartment = 0xFF;
  while (true) {
    char key = keypad.getKey();
    if (key >= '1' && key <= '8') { compartment = key - '1'; break; }
    if (key == 'D') { lcd.clear(); lcd.print("Canceled"); delay(800); return; }
  }

  if (alarmCount[compartment] > 0) {
    while (true) {
      lcd.clear(); lcd.print("Del n(1-"); lcd.print(alarmCount[compartment]); lcd.print("):");
      lcd.setCursor(0,1);
      for (byte i=0; i<alarmCount[compartment] && i<2; i++) {
        if (alarms[compartment][i].hour < 10) lcd.print('0');
        lcd.print(alarms[compartment][i].hour);
        lcd.print(":");
        if (alarms[compartment][i].minute < 10) lcd.print('0');
        lcd.print(alarms[compartment][i].minute);
        if (i == 0 && alarmCount[compartment]>1) lcd.print(' ');
      }
      if (alarmCount[compartment]>2) lcd.print("+");

      unsigned long t0 = millis();
      while (millis()-t0<1500) {
        char key = keypad.getKey();
        if (key >= '1' && key <= ('0'+alarmCount[compartment])) {
          byte idx = key - '1';
          for (byte j=idx; j<alarmCount[compartment]-1; j++) alarms[compartment][j] = alarms[compartment][j+1];
          alarmCount[compartment]--;
          lcd.clear(); lcd.print("Deleted!"); delay(1000); return;
        }
        if (key == 'D') { lcd.clear(); lcd.print("Canceled"); delay(800); return; }
      }
    }
  } else {
    lcd.clear(); lcd.print("No Alarm"); delay(1000);
  }
}

//4. 展示提醒时间
void displayAlarms() {
  lcd.clear();
  lcd.print("Box(1-8)?:");
  byte compartment = 0xFF;
  while (true) {
    char key = keypad.getKey();
    if (key && key >= '1' && key <= '8') {
      compartment = key - '1';
      break;
    }
    if (key == 'D') {
      lcd.clear();
      lcd.print("Canceled");
      delay(800);
      return;
    }
  }
  lcd.clear();
  lcd.print("Box");
  lcd.print(compartment+1);
  lcd.print(":");
  lcd.setCursor(0,1);
  if (alarmCount[compartment] == 0) {
    lcd.print("None");
    delay(1500);
    return;
  }
  // 循环显示该隔间全部提醒，支持翻页或退出
  byte idx = 0;
  while (true) {
    lcd.setCursor(0,1);
    lcd.print("                "); // 清空下排
    lcd.setCursor(0,1);
    lcd.print(idx+1);
    lcd.print(": ");
    if (alarms[compartment][idx].hour < 10) lcd.print("0");
    lcd.print(alarms[compartment][idx].hour);
    lcd.print(":");
    if (alarms[compartment][idx].minute < 10) lcd.print("0");
    lcd.print(alarms[compartment][idx].minute);
    lcd.print("            ");
    lcd.print("(*=prev, #=next)");
    // 按#前翻，*后翻，D退出
    unsigned long t0 = millis();
    while (millis() - t0 < 5000) { // 5秒自动退出，也可根据需求不设定自动退出
      char k = keypad.getKey();
      if (k == '*') { // 上一个
        if (idx > 0) idx--;
        break;
      } else if (k == '#') { // 下一个
        if (idx < alarmCount[compartment]-1) idx++;
        break;
      } else if (k == 'D') { // 退出
        lcd.clear();
        lcd.print("Exit");
        delay(800);
        return;
      }
    }
  }
}


//5. 检查提醒时间
void checkMedicationTime() {
  DateTime now = rtc.now();
  for(byte c=0; c<8; c++) {
    for(byte a=0; a<alarmCount[c]; a++) {
      if(now.hour() == alarms[c][a].hour && now.minute() == alarms[c][a].minute && now.second() == 0) {
        alertMedication(c+1);
      }
    }
  }
}

//6. 提醒执行
void alertMedication(byte compartment) {
  lcd.clear();
  lcd.print("Box");
  lcd.print(compartment);
  lcd.print(" Take Med!");
  // 持续提醒（最多10秒，每0.5秒闪烁一次，最多20次）
  for (int i = 0; i < 20; i++) {
    digitalWrite(ledPin, HIGH);
    digitalWrite(buzzerPin, HIGH);
    unsigned long t0 = millis();
    // 在蜂鸣/亮灯期间检查按键
    while (millis() - t0 < 250) {
      if (keypad.getKey()) {
        digitalWrite(ledPin, LOW);
        digitalWrite(buzzerPin, LOW);
        lcd.clear();
        lcd.print("Stopped");
        delay(1000);
        lcd.clear();
        return;
      }
    }
    digitalWrite(ledPin, LOW);
    digitalWrite(buzzerPin, LOW);
    t0 = millis();
    while (millis() - t0 < 250) {
      if (keypad.getKey()) {
        lcd.clear();
        lcd.print("Stopped");
        delay(1000);
        lcd.clear();
        return;
      }
    }
  }
  digitalWrite(ledPin, LOW);
  lcd.clear();
  lcd.print("Done");
  delay(1000);
  lcd.clear();
}