#include <Wire.h>
#include <RTClib.h>
#include <LiquidCrystal.h>

// 初始化DS1307
RTC_DS1307 rtc;

// 初始化LCD (RS, EN, D4, D5, D6, D7)
LiquidCrystal lcd(12, 11, 10, 9, 8, 4);

// LED设置
const int ledPin = 2;  // LED接数字引脚2
bool ledState = false; // LED状态跟踪

void setup() {
  Serial.begin(9600);
  
  // 初始化LED引脚
  pinMode(ledPin, OUTPUT);
  
  // 初始化LCD
  lcd.begin(16, 2);
  lcd.print("Initializing...");
  
  // 初始化RTC
  if (!rtc.begin()) {
    Serial.println("Couldn't find RTC");
    lcd.clear();
    lcd.print("RTC Error!");
    while (1);
  }
  
  // 检查RTC是否运行
  if (!rtc.isrunning()) {
    Serial.println("RTC is NOT running!");
    // 设置编译时间为初始时间
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }
  
  // 清除LCD并显示初始信息
  lcd.clear();
  lcd.print("Clock Ready");
  delay(1000);
}

void loop() {
  // 获取当前时间
  DateTime now = rtc.now();
  
  // 控制LED闪烁
  ledState = !ledState; // 切换LED状态
  digitalWrite(ledPin, ledState ? HIGH : LOW);
  
  // 格式化日期和时间字符串
  char dateString[20];
  char timeString[20];
  
  snprintf_P(dateString, 
            sizeof(dateString),
            PSTR("%04u-%02u-%02u"),
            now.year(),
            now.month(),
            now.day());
  
  snprintf_P(timeString, 
            sizeof(timeString),
            PSTR("%02u:%02u:%02u"),
            now.hour(),
            now.minute(),
            now.second());
  
  // 在LCD上显示
  lcd.setCursor(0, 0);
  lcd.print("Date: ");
  lcd.print(dateString);
  
  lcd.setCursor(0, 1);
  lcd.print("Time: ");
  lcd.print(timeString);
  
  // 每秒更新一次
  delay(1000);
}