From 00d717d9dd00e7c99843d2c7149d898e1cae1823 Mon Sep 17 00:00:00 2001
From: Nicu Hodos <nicu@hodos.ro>
Date: Mon, 2 Nov 2020 16:46:50 +0000
Subject: [PATCH] use time library and daylight savings

---
 esp_clock.ino | 100 ++++++++++++++++++--------------------------------
 1 file changed, 36 insertions(+), 64 deletions(-)

diff --git a/esp_clock.ino b/esp_clock.ino
index 9997dcc..4174502 100644
--- a/esp_clock.ino
+++ b/esp_clock.ino
@@ -1,7 +1,4 @@
-//##########################################################################
-// Includes and defines
-//##########################################################################
-
+#include <Arduino.h>
 #include <ESP8266WiFi.h>
 #include <ESP8266WiFiMulti.h>
 #include <NTPClient.h>
@@ -10,41 +7,38 @@
 #include <ArduinoOTA.h>
 #include <Adafruit_LEDBackpack.h>   // Support for the Backpack FeatherWing
 #include <Adafruit_GFX.h>           // Adafruit's graphics library
+#include <SPI.h>
+#include <Timezone.h>
+#include <time.h>
 
-#define TIME_24_HOUR
 #define DISPLAY_ADDRESS 0x70
 #define BRIGHTNESS 1
 
-//##########################################################################
-// Globals
-//##########################################################################
-
 // Create display object
 Adafruit_7segment clockDisplay = Adafruit_7segment();
 
-int hours = 0;                      // Track hours
-int minutes = 0;                    // Track minutes
-int seconds = 0;                    // Track seconds
-int tzOffset = +2;                  // Time zone offset (-4 = US Eastern time)
+// Central European Time (Frankfurt, Paris)
+TimeChangeRule CEST = {"CEST", Last, Sun, Mar, 2, 120};     // Central European Summer Time
+TimeChangeRule CET = {"CET ", Last, Sun, Oct, 3, 60};       // Central European Standard Time
+Timezone CE(CEST, CET);
 
-#ifdef TIME_24_HOUR
-byte displayHours[24] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23};
-#else
-byte displayHours[24] = {12, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11};
-#endif
+int currentHour = -1;
 
-int status = WL_IDLE_STATUS;
-bool shouldUpdate = true;
 String currentSSID;
 String currentPsk;
 
-ESP8266WiFiMulti wifiMulti;
 WiFiUDP ntpUDP;
-NTPClient timeClient(ntpUDP, "europe.pool.ntp.org", tzOffset*3600);
+NTPClient timeClient(ntpUDP, "europe.pool.ntp.org");
+
+void displayTime();
+void displayColon(bool on);
+void setupOTA();
+void printWiFiStatus();
 
 void setup() {
   Serial.begin(9600);                      // Start the serial console
 
+  ESP8266WiFiMulti wifiMulti;
   wifiMulti.addAP("vulturul", "***REMOVED***");
   wifiMulti.addAP("Miracle", "***REMOVED***");
   
@@ -55,7 +49,6 @@ void setup() {
   Serial.println("Connected to network.");
   currentSSID = WiFi.SSID();
   currentPsk = WiFi.psk();
-  printWiFiStatus();                         // Display WiFi status data
 
   setupOTA();
 
@@ -68,15 +61,23 @@ void setup() {
 void loop() {
   ArduinoOTA.handle();
   
-  if (shouldUpdate && WiFi.status() == WL_CONNECTED && timeClient.forceUpdate()) {
-    shouldUpdate = false;
-    hours = timeClient.getHours();
-    minutes = timeClient.getMinutes();
-    seconds = timeClient.getSeconds();
-    Serial.println(timeClient.getFormattedTime());
+  if ((currentHour != hour())) {
+    if (WiFi.status() != WL_CONNECTED) {
+      WiFi.forceSleepWake();
+      WiFi.begin(currentSSID.c_str(), currentPsk.c_str());
+      Serial.println("Reconnecting to WiFi netowrk...");
+      for (int i = 0; i < 4; i++) {
+        delay(1000);
+      }
+    }
+    printWiFiStatus();
+    if (WiFi.status() == WL_CONNECTED && timeClient.forceUpdate()) {
+      time_t newTime = CE.toLocal(timeClient.getEpochTime());
+      setTime(newTime);
+      Serial.println(asctime(localtime(&newTime)));
+    }
     WiFi.forceSleepBegin();
-  } else {
-    incrementTime();
+    currentHour = hour();
   }
   displayTime();
   displayColon(true);
@@ -85,35 +86,10 @@ void loop() {
   delay(500);
 }
 
-void incrementTime() {
-  if (++seconds >= 60) {
-    seconds = 0;
-    if (++minutes == 60) {
-      minutes = 0;
-      Serial.println("Minutes set to zero - should query NTP on next loop()");
-      if (++hours == 24) hours = 0;
-    }
-    if ((minutes == 0)) {
-      WiFi.forceSleepWake();
-      WiFi.begin(currentSSID.c_str(), currentPsk.c_str());
-      for (int i = 0; i < 4; i++) {
-        Serial.println("Reconnecting to WiFi netowrk...");
-        delay(1000);
-        seconds++;
-      }
-      if (WiFi.status() == WL_CONNECTED) {
-    	  shouldUpdate = true;
-      } else {
-    	  WiFi.forceSleepBegin();
-      }
-      printWiFiStatus();
-    }
-  }
-}
-
 void displayTime() {
-  int displayHour = displayHours[hours];
-  int displayValue = displayHour*100 + minutes;
+  int displayHour = hour();
+  int displayMinute = minute();
+  int displayValue = displayHour*100 + displayMinute;
 
   // Print the time on the display
   clockDisplay.print(displayValue, DEC);
@@ -123,7 +99,7 @@ void displayTime() {
   // which can look confusing.  Go in and explicitly add these zeros.
   if (displayHour == 0) {
     clockDisplay.writeDigitNum(1, 0);
-    if (minutes < 10) {
+    if (displayMinute < 10) {
       clockDisplay.writeDigitNum(3, 0);
     }
   }
@@ -131,7 +107,6 @@ void displayTime() {
 
 void displayColon(bool on) {
 	  clockDisplay.drawColon(on);
-
 	  clockDisplay.writeDisplay();
 }
 
@@ -154,9 +129,6 @@ void setupOTA() {
 	    else if (error == OTA_END_ERROR) Serial.println("End Failed");
 	  });
 	  ArduinoOTA.begin();
-	  Serial.println("Ready");
-	  Serial.print("IP address: ");
-	  Serial.println(WiFi.localIP());
 }
 
 void printWiFiStatus() {