/*
 * LED matrix Clock with DHT22 Temperature and Humidity
 * Modified from original by Uncle Da
 * Added date, AM/PM, temperature and humidity display
 * Last Update: April 10, 2025
 */

#include <WiFi.h>      //ESP32
//#include <ESP8266WiFi.h>  //ESP8266
#include <MD_Parola.h>  //For MAX7219 Matrix LED
#include <MD_MAX72xx.h> //For MAX7219 SPI LED Driver
#include <SPI.h>        //For SPI Communication
#include <time.h>       //For Time Based Application 
#include "Font.h"  
#include <DHT.h>        //For DHT22 Sensor

//**********  User Config Setting   ******************************/
const char *ssid = "Wokwi-GUEST";   //Change to your WiFi SSID
const char *password = "";        //Password 
const char *NTPServer = "pool.ntp.org";
const int gmtOffset_sec = 28800;  //8*3600 (GMT+8)
const int daylightOffset_sec = 0;  //Daylight savings

//=====MAX7219================================
#define HARDWARE_TYPE MD_MAX72XX::PAROLA_HW   //Change to FC16_HW if needed
#define MAX_DEVICES 4 
#define CLK_PIN   18
#define DATA_PIN  23
#define CS_PIN    5
MD_Parola P = MD_Parola(HARDWARE_TYPE, DATA_PIN, CLK_PIN, CS_PIN, MAX_DEVICES);
#define SPEED_TIME  60  //Lower number = faster
#define PAUSE_TIME  1000  //Display pause time in milliseconds

//=====DHT22 Sensor Setup===================
#define DHTPIN 15     // Digital pin connected to the DHT sensor
#define DHTTYPE DHT22   // DHT 22 (AM2302)
DHT dht(DHTPIN, DHTTYPE);
float temperature = 0.0;
float humidity = 0.0;
unsigned long lastDHTReadTime = 0;
#define DHT_READ_INTERVAL 2000  // Read DHT22 every 2 seconds

//=====Display Variables=====================
uint16_t h, m, s;
char szTime[9];         // HH:MM\0
char szDate[11];        // MM/DD/YY\0
char szAMPM[3];         // AM/PM
char szTemp[7];         // XX.X°C
char szHumid[7];        // XX.X%
char szSecond[4];       // SS
bool isPM = false;

// Display mode enum to track what we're showing
enum DisplayMode {
  SHOW_TIME,
  SHOW_DATE,
  SHOW_TEMP,
  SHOW_HUMID,
  DISPLAY_MODES_COUNT  // Number of display modes
};

DisplayMode currentMode = SHOW_TIME;
unsigned long lastModeChangeTime = 0;
#define MODE_CHANGE_INTERVAL 5000  // Change display mode every 5 seconds

//=============================================
void getSecond(char *szSecond)
{
  sprintf(szSecond, "%02d", s);
}

//=============================================
void updateTimeAndDate()
{
  time_t now = time(nullptr);
  struct tm* p_tm = localtime(&now);
  
  h = p_tm->tm_hour;
  m = p_tm->tm_min;
  s = p_tm->tm_sec;
  
  // Format time
  if (h >= 12) {
    isPM = true;
    strcpy(szAMPM, "PM");
    if (h > 12) h -= 12;  // Convert to 12-hour format
  } else {
    isPM = false;
    strcpy(szAMPM, "AM");
    if (h == 0) h = 12;  // 0 hour = 12 AM
  }
  
  sprintf(szTime, "%2d:%02d", h, m);  // HH:MM in 12-hour format
  
  // Format date (MM/DD/YY)
  sprintf(szDate, "%02d/%02d/%02d", 
          p_tm->tm_mon + 1,   // Month (0-11, so add 1)
          p_tm->tm_mday,      // Day of month
          p_tm->tm_year % 100); // Year (since 1900, so get last 2 digits)
  
  Serial.printf("%04d-%02d-%02d %02d:%02d:%02d %s\n", 
                p_tm->tm_year + 1900, p_tm->tm_mon + 1, p_tm->tm_mday,
                h, m, s, szAMPM);
  
  // Check if we need to change the display mode
  if (millis() - lastModeChangeTime >= MODE_CHANGE_INTERVAL) {
    currentMode = static_cast<DisplayMode>((currentMode + 1) % DISPLAY_MODES_COUNT);
    lastModeChangeTime = millis();
    P.displayReset(1);  // Reset zone 1 display
  }
}

//=============================================
void readDHT()
{
  // Read DHT sensor only every DHT_READ_INTERVAL milliseconds
  if (millis() - lastDHTReadTime >= DHT_READ_INTERVAL) {
    humidity = dht.readHumidity();
    temperature = dht.readTemperature();
    
    // Check if readings are valid
    if (isnan(humidity) || isnan(temperature)) {
      Serial.println("Failed to read from DHT sensor!");
      strcpy(szTemp, "Error");
      strcpy(szHumid, "Error");
    } else {
      sprintf(szTemp, "%2.1fC", temperature);
      sprintf(szHumid, "%2.1f%%", humidity);
      Serial.printf("Temperature: %2.1f°C, Humidity: %2.1f%%\n", temperature, humidity);
    }
    
    lastDHTReadTime = millis();
  }
}

// ============SmartConfig/Auto Reconnect/WeChat Scan Config====================
void SmartConfig()   
{
  WiFi.mode(WIFI_STA);
  Serial.println("\r\nWait for Smartconfig...");
  WiFi.beginSmartConfig();
  while (1)
  {
    Serial.print(".");
    delay(500);                   // wait for a second
    if (WiFi.smartConfigDone())
    {
      Serial.println("SmartConfig Success");
      Serial.printf("SSID:%s\r\n", WiFi.SSID().c_str());
      Serial.printf("PSW:%s\r\n", WiFi.psk().c_str());
      break;
    }
  }
}

bool AutoConfig()   //Auto reconnect on power-up
{
    WiFi.begin();
    for (int i = 0; i < 20; i++)
    {
        int wstatus = WiFi.status();
        if (wstatus == WL_CONNECTED)
        {
          Serial.println("WIFI SmartConfig Success");
          Serial.printf("SSID:%s", WiFi.SSID().c_str());
          Serial.printf(", PSW:%s\r\n", WiFi.psk().c_str());
          Serial.print("LocalIP:");
          Serial.print(WiFi.localIP());
          Serial.print(" ,GateIP:");
          Serial.println(WiFi.gatewayIP());
          return true;
        }
        else
        {
          Serial.print("WIFI AutoConfig Waiting......");
          Serial.println(wstatus);
          delay(1000);
        }
    }
    Serial.println("WIFI AutoConfig Failed!" );
    return false;
}
//===================================================

void setup()
{
  Serial.begin(115200);
  delay(50);
  
  // Initialize DHT sensor
  dht.begin();
  
  // Initialize LED Matrix
  P.begin(2);   // Split into 2 zones
  P.setInvert(false); // false = normal display, true = inverted
  
  // Initialize WiFi
  Serial.println();
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);
  Serial.print("Connecting to ");
  Serial.println(ssid);
  
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
  delay(1000);
  
  // Get time from NTP
  getTimeNTP();
  
  if (!AutoConfig()) {
    SmartConfig();
  }
  
  // Set up display zones
  P.setZone(0, 0, 0);   // Zone 0: rightmost 8x8 matrix for seconds
  P.setZone(1, 1, 3);   // Zone 1: matrices 1-3 for everything else
  
  P.setFont(0, GF3x5p);  // Font for seconds (smaller)
  P.setFont(1, GF4x7p);  // Font for main display
  
  P.displayZoneText(0, szSecond, PA_RIGHT, SPEED_TIME, 0, PA_PRINT, PA_NO_EFFECT);
  P.displayZoneText(1, szTime, PA_CENTER, SPEED_TIME, 0, PA_PRINT, PA_NO_EFFECT);
  
  // Initial readings
  readDHT();
  updateTimeAndDate();
}

//=============================================
void loop() {
  P.displayAnimate();
  
  updateTimeAndDate();
  readDHT();
  getSecond(szSecond);
  
  // Reset seconds display
  P.displayReset(0); 
  
  // Update main display based on current mode
  char displayBuffer[20] = {0};
  
  switch (currentMode) {
    case SHOW_TIME:
      sprintf(displayBuffer, "%s %s", szTime, szAMPM);
      break;
    case SHOW_DATE:
      strcpy(displayBuffer, szDate);
      break;
    case SHOW_TEMP:
      strcpy(displayBuffer, szTemp);
      break;
    case SHOW_HUMID:
      strcpy(displayBuffer, szHumid);
      break;
    default:
      strcpy(displayBuffer, szTime);
      break;
  }
  
  P.displayZoneText(1, displayBuffer, PA_CENTER, SPEED_TIME, 0, PA_PRINT, PA_NO_EFFECT);
  P.displayReset(1);
  
  // Adjust brightness based on time of day
  int hour24 = isPM ? (h + 12) : h;  // Convert back to 24-hour format
  if (hour24 >= 0 && hour24 < 7) {  // Night mode (midnight to 7am)
    P.setIntensity(0, 1); // Zone 0 brightness = 1
    P.setIntensity(1, 1); // Zone 1 brightness = 1
  } else {
    P.setIntensity(0, 3); // Zone 0 brightness = 3
    P.setIntensity(1, 3); // Zone 1 brightness = 3
  }
  
  // Auto restart at 00:20:00
  if (hour24 == 0 && m == 20 && s == 0) {  
    P.displayClear();
    delay(1000);
    ESP.restart();
  }
}

//=============================================
void getTimeNTP()  // NTP time server
{
  configTime(gmtOffset_sec, daylightOffset_sec, NTPServer);
  
  while(!time(nullptr)) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("NTP Time Update Complete");
}