main: more sophisticated WiFi setup

- Try to find an AP 10 times, then set up our own
- When connected to an AP and the connection is lost, restart the WiFi
  setup
- Initialize the LEDs before the WiFi, so we are able to (maybe?)
  display messages on the LEDs

src/main.cpp

@@ -3,6 +3,7 @@
 #include <Arduino.h>
 #include <WiFi.h>
 #include <WiFiMulti.h>
+#include <SPIFFS.h>
 
 #include "WLAN_Logins.h"
 #include "HTTPServer.h"
@@ -25,7 +26,7 @@ bool led_on = false;
 size_t led_idx;
 size_t frame;
 
-WiFiMulti WiFiMulti;
+WiFiMulti wiFiMulti;
 
 Fader ledFader(NUM_STRIPS, NUM_LEDS);
 UDPProto udpProto(&ledFader);
@@ -86,7 +87,9 @@ static void ledTask( void * parameter )
 
     uint32_t start_time = micros();
 
-    udpProto.loop();
+    if(WiFi.status() == WL_CONNECTED) {
+      udpProto.loop();
+    }
 
     led_idx++;
     if(led_idx >= STRANDS[0].numPixels) {
@@ -134,6 +137,40 @@ static void ledTask( void * parameter )
   vTaskDelete( NULL );
 }
 
+void wifi_setup(void)
+{
+  Serial.println("Trying to connect...");
+
+  for(size_t tries = 0; tries < 10; tries++)
+  {
+    if(wiFiMulti.run() == WL_CONNECTED) {
+      Serial.println("");
+      Serial.println("WiFi connected");
+      Serial.println("IP address: ");
+      Serial.println(WiFi.localIP());
+      break;
+    }
+
+    led_on = !led_on;
+    digitalWrite(2, led_on);
+    delay(100);
+
+    Serial.print(".");
+  }
+
+  if(WiFi.status() != WL_CONNECTED) {
+    Serial.println("Connection failed, setting up access point...");
+
+    IPAddress apIP(192, 168, 42, 1);
+
+    WiFi.mode(WIFI_AP);
+    WiFi.softAPConfig(apIP, apIP, IPAddress(255, 255, 255, 0));
+    WiFi.softAP("🕯️💡☀️", "Licht234");
+    WiFi.enableAP(true);
+  }
+
+}
+
 void setup()
 {
   pinMode(2, OUTPUT); // On-Board LED
@@ -148,38 +185,18 @@ void setup()
     }
   }
 
-  // We start by connecting to a WiFi network
+  if(!SPIFFS.begin()) {
+    Serial.println("SPIFFS setup failed!");
+    while(true) {
+      delay(100);
+    }
+  }
 
   digitalWrite(2, HIGH);
 
   Serial.println();
   Serial.println();
 
-  for (auto &net : NETWORKS)
-  {
-    Serial.print("Adding network ");
-    Serial.println(net.ssid);
-    WiFiMulti.addAP(net.ssid, net.password);
-  }
-
-  while (WiFiMulti.run() != WL_CONNECTED)
-  {
-    led_on = !led_on;
-    digitalWrite(2, led_on);
-    delay(250);
-
-    Serial.print(".");
-  }
-
-  Serial.println("");
-  Serial.println("WiFi connected");
-  Serial.println("IP address: ");
-  Serial.println(WiFi.localIP());
-
-  HTTPServer::instance().setFader(&ledFader);
-
-  udpProto.start(2703);
-
   ledFader.set_color(Fader::Color{64,0,0,0});
   ledFader.fade_color(Fader::Color{0,64,0,0});
 
@@ -191,6 +208,21 @@ void setup()
       2,                        /* priority of the task */
       NULL);                    /* Task handle to keep track of created task */
 
+  // Connect the WiFi network (or start an AP if that doesn't work)
+  for (auto &net : NETWORKS)
+  {
+    Serial.print("Adding network ");
+    Serial.println(net.ssid);
+    wiFiMulti.addAP(net.ssid, net.password);
+  }
+
+  wifi_setup();
+
+  // start the UDP server
+  udpProto.start(2703);
+
+  // start the web server
+  HTTPServer::instance().setFader(&ledFader);
   HTTPServer::instance().start();
 }
 
@@ -198,8 +230,10 @@ void loop() {
   led_on = !led_on;
   digitalWrite(2, led_on);
   delay(500);
-  //Serial.print("RSSI: ");
-  //Serial.println(WiFi.RSSI());
 
-  //server.loop();
+  // reconnect WiFi when connection is lost
+  if(WiFi.status() == WL_CONNECTION_LOST) {
+    Serial.println("WLAN disconnected. Restarting setup.");
+    wifi_setup();
+  }
 }