#include <ESP8266WiFi.h>
#include <ESP8266WiFiMulti.h>
#include <ezTime.h>

ESP8266WiFiMulti wifiMulti;

#include <MD_MAX72xx.h>
#include <SPI.h>

// Define the number of devices we have in the chain and the hardware interface
// NOTE: These pin numbers will probably not work with your hardware and may
// need to be adapted
#define HARDWARE_TYPE MD_MAX72XX::FC16_HW
#define MAX_DEVICES 4

#define DATA_PIN  14  // or MOSI (D5 on NodeMCU)
#define CS_PIN    12  // or SS  (D6 on NodeMCU)
#define CLK_PIN   13  // or SCK (D7 on NodeMCU)

// SPI hardware interface
//MD_MAX72XX mx = MD_MAX72XX(HARDWARE_TYPE, CS_PIN, MAX_DEVICES);
// Arbitrary pins
MD_MAX72XX mx = MD_MAX72XX(HARDWARE_TYPE, DATA_PIN, CLK_PIN, CS_PIN, MAX_DEVICES);

// Text parameters
#define CHAR_SPACING  1 // pixels between characters

// Global message buffers shared by Serial and Scrolling functions
#define BUF_SIZE  6
char message[BUF_SIZE] = "00:00";

void printText(uint8_t modStart, uint8_t modEnd, const char *pMsg)
// Print the text string to the LED matrix modules specified.
// Message area is padded with blank columns after printing.
{
  uint8_t   state = 0;
  uint8_t   curLen;
  uint16_t  showLen;
  uint8_t   cBuf[8];
  int16_t   col = ((modEnd + 1) * COL_SIZE) - 1;

  mx.control(modStart, modEnd, MD_MAX72XX::UPDATE, MD_MAX72XX::OFF);

  do     // finite state machine to print the characters in the space available
  {
    switch (state)
    {
      case 0: // Load the next character from the font table
        // if we reached end of message, reset the message pointer
        if (*pMsg == '\0')
        {
          showLen = col - (modEnd * COL_SIZE);  // padding characters
          state = 2;
          break;
        }

        // retrieve the next character form the font file
        showLen = mx.getChar(*pMsg++, sizeof(cBuf) / sizeof(cBuf[0]), cBuf);
        curLen = 0;
        state++;
      // !! deliberately fall through to next state to start displaying

      case 1: // display the next part of the character
        mx.setColumn(col--, cBuf[curLen++]);

        // done with font character, now display the space between chars
        if (curLen == showLen)
        {
          showLen = CHAR_SPACING;
          state = 2;
        }
        break;

      case 2: // initialize state for displaying empty columns
        curLen = 0;
        state++;
      // fall through

      case 3: // display inter-character spacing or end of message padding (blank columns)
        mx.setColumn(col--, 0);
        curLen++;
        if (curLen == showLen)
          state = 0;
        break;

      default:
        col = -1;   // this definitely ends the do loop
    }
  } while (col >= (modStart * COL_SIZE));

  mx.control(modStart, modEnd, MD_MAX72XX::UPDATE, MD_MAX72XX::ON);
}

void setWifi() {
  Serial.print("Connecting to wifi: ");
  printText(0, MAX_DEVICES - 1, "WiFi");
  WiFi.mode(WIFI_STA);
  wifiMulti.addAP("XXX", "XXX");
  wifiMulti.addAP("XXX", "XXX");
  wifiMulti.addAP("XXX ", "XXX");
  while (wifiMulti.run() != WL_CONNECTED) { // Wait for the Wi-Fi to connect: scan for Wi-Fi networks, and connect to the strongest of the networks above
    delay(1000);
    Serial.print('.');
  }
  Serial.println();
}

Timezone myTZ;
void setClock() {
  printText(0, MAX_DEVICES - 1, "NTP");
  // Make ezTime show us what it is doing
  setDebug(INFO);
  // Wait for ezTime to get its time synchronized
  waitForSync();
  // See if local time can be obtained (does not work in countries that span multiple timezones)
  if (myTZ.setLocation()) {
    Serial.println(myTZ.dateTime());
  } else {
    Serial.println(errorString());
    myTZ.setPosix(F("CET-1CEST,M3.5.0,M10.5.0/3")); // Europe/Paris
  }
  myTZ.setDefault();
  Serial.println(myTZ.dateTime());
  // Set NTP polling interval to 1 hour.
  setInterval(60 * 60);
}

void setup() {
  mx.begin();

  Serial.begin(115200);
  Serial.println();
  setWifi();
  setClock();
}

bool showColon = true;
void loop() {
  // Register ezTime events
  events();
  if (secondChanged()) {
    showColon = !showColon;
    char dateFormat[BUF_SIZE] = "H:i";
    if (!showColon) {
      strcpy(dateFormat, "H i");
    }
    printText(0, MAX_DEVICES - 1, dateTime(dateFormat).c_str());
  }
}