E-INK Live Flight Scanner

#include <Arduino.h>
#include <WiFi.h>
#include <WiFiManager.h>
#include <TFT_eSPI.h>
#include <WiFiClientSecure.h>
#include <HTTPClient.h>
#include <ArduinoJson.h>
#include <time.h>
#include <math.h>
EPaper epaper;
WiFiManager wm;
struct Plane {String name,type;float km,bearing,track,alt,speed;bool altitude;};
Plane planes[40];int count=0;bool haveData=false,first=true;String errorText="Waiting for network",stamp="--";uint32_t nextPoll=0;
const float LAT=53.6304f,LON=9.9882f;
uint32_t offlineSince=0,lastReconnect=0;bool wasConnected=false;
int lastWifiStatus=-1;
bool setupPagePending=false;
uint32_t setupVisibleUntil=0;
void showSetupPage();
float rad(float d){return d*PI/180.0f;}
float distance(float lat,float lon){float a=sin(rad(lat-LAT)/2),b=sin(rad(lon-LON)/2);float q=constrain(a*a+cos(rad(LAT))*cos(rad(lat))*b*b,0.0f,1.0f);return 12742*atan2(sqrt(q),sqrt(1-q));}
float bearing(float lat,float lon){return fmod(atan2(sin(rad(lon-LON))*cos(rad(lat)),cos(rad(LAT))*sin(rad(lat))-sin(rad(LAT))*cos(rad(lat))*cos(rad(lon-LON)))*180/PI+360,360);}
void text(int x,int y,const String&s,int size=1,uint16_t c=TFT_BLACK){epaper.setTextSize(size);epaper.setTextColor(c,TFT_WHITE);epaper.setCursor(x,y);epaper.print(s);}
String clockText(){tm t;if(!getLocalTime(&t,5000))return "time not synced";char b[32];strftime(b,sizeof b,"%d.%m %H:%M:%S %Z",&t);return String(b);}
bool fetch(){
 if(WiFi.status()!=WL_CONNECTED){errorText="Wi-Fi disconnected";WiFi.reconnect();return false;}
 WiFiClientSecure client;client.setInsecure();client.setHandshakeTimeout(12);HTTPClient http;http.setTimeout(15000);http.setConnectTimeout(10000);http.useHTTP10(true);
 if(!http.begin(client,"https://opendata.adsb.fi/api/v3/lat/53.6304/lon/9.9882/dist/41")){errorText="Connection failed";return false;}
 http.setUserAgent("HamburgFlightScanner/1.0 (reTerminal E1002)");
 http.addHeader("Accept","application/json");
 int status=http.GET();if(status!=200){errorText="Service HTTP "+String(status);http.end();return false;}
 JsonDocument filter;for(const char* list:{"ac","aircraft"}){JsonObject f=filter[list].add<JsonObject>();for(const char*k:{"flight","hex","t","lat","lon","alt_baro","alt_geom","gs","track","seen_pos"})f[k]=true;}
 JsonDocument doc;auto err=deserializeJson(doc,http.getStream(),DeserializationOption::Filter(filter));http.end();if(err){errorText="Unreadable flight data";return false;}
 JsonArray ac=doc["ac"].as<JsonArray>();if(ac.isNull())ac=doc["aircraft"].as<JsonArray>();if(ac.isNull()){errorText="Missing aircraft list";return false;}
 Plane fresh[40];int n=0;
 for(JsonObject a:ac){if(a["lat"].isNull()||a["lon"].isNull()||(a["seen_pos"]|0.0f)>60||a["alt_baro"].is<const char*>())continue;
 float lat=a["lat"]|0.0f,lon=a["lon"]|0.0f;Plane p;p.km=distance(lat,lon);if(p.km>75)continue;p.bearing=bearing(lat,lon);p.track=a["track"]|p.bearing;p.speed=(a["gs"]|0.0f)*1.852f;p.name=String(a["flight"]|"");p.name.trim();if(p.name.isEmpty())p.name=String(a["hex"]|"?");p.type=String(a["t"]|"?");p.altitude=!a["alt_baro"].isNull()||!a["alt_geom"].isNull();p.alt=(a["alt_baro"].isNull()?(a["alt_geom"]|0.0f):(a["alt_baro"]|0.0f))*0.3048f;
 if(n<40)fresh[n++]=p;else{int far=0;for(int i=1;i<n;i++)if(fresh[i].km>fresh[far].km)far=i;if(p.km<fresh[far].km)fresh[far]=p;}}
 for(int i=0;i<n;i++)for(int j=i+1;j<n;j++)if(fresh[j].km<fresh[i].km){Plane p=fresh[i];fresh[i]=fresh[j];fresh[j]=p;}count=n;for(int i=0;i<n;i++)planes[i]=fresh[i];haveData=true;errorText="";return true;
}
uint16_t color(const Plane&p){return !p.altitude?TFT_BLACK:p.alt<3048?TFT_GREEN:p.alt<7620?TFT_BLUE:TFT_RED;}
void draw(){
 // Timestamp this successful display refresh in Hamburg local time.
 // Failed requests keep the last successful refresh timestamp.
 if(haveData && errorText.isEmpty())stamp=clockText();
 epaper.fillScreen(TFT_WHITE);text(16,14,"HAMBURG AIR TRAFFIC",3);text(18,48,"HAM airport | 75 km radius | north up");epaper.drawLine(12,68,788,68,TFT_BLACK);
 const int cx=210,cy=267,R=164;for(int i=1;i<=3;i++){epaper.drawCircle(cx,cy,R*i/3,TFT_BLACK);text(cx+5,cy+R*i/3-12,String(i*25)+" km");}epaper.drawLine(cx-R,cy,cx+R,cy,TFT_BLACK);epaper.drawLine(cx,cy-R,cx,cy+R,TFT_BLACK);text(cx-4,cy-R-17,"N");text(cx-4,cy+R+5,"S");text(cx-R-16,cy-4,"W");text(cx+R+8,cy-4,"E");
 for(int i=count-1;i>=0;i--){Plane&p=planes[i];float d=p.km/75*R;int x=cx+lround(d*sin(rad(p.bearing))),y=cy-lround(d*cos(rad(p.bearing)));float a=rad(p.track);epaper.fillTriangle(x+lround(9*sin(a)),y-lround(9*cos(a)),x+lround(-6*sin(a)-5*cos(a)),y+lround(6*cos(a)-5*sin(a)),x+lround(-6*sin(a)+5*cos(a)),y+lround(6*cos(a)+5*sin(a)),color(p)); }
 // Place every label in its own box; leader lines link displaced labels to symbols.
 int lx[40],ly[40],lw[40];
 for(int i=0;i<count;i++){
  Plane&p=planes[i];float d=p.km/75*R;
  int x=cx+lround(d*sin(rad(p.bearing))),y=cy-lround(d*cos(rad(p.bearing)));
  String label=p.name.substring(0,9);int w=label.length()*6+4;
  int bestX=20,bestY=90;long best=2147483647L;
  for(int yy=90;yy<=426;yy+=12)for(int xx=20;xx+w<=400;xx+=6){
   bool free=true;
   if(xx<cx+22&&xx+w>cx-12&&yy<cy+22&&yy+10>cy-10)free=false;
   for(int j=0;j<i&&free;j++)if(xx<lx[j]+lw[j]+2&&xx+w+2>lx[j]&&yy<ly[j]+12&&yy+12>ly[j])free=false;
   if(!free)continue;
   long dx=xx+w/2-x,dy=yy+5-y,score=dx*dx+dy*dy;
   if(score<best){best=score;bestX=xx;bestY=yy;}
  }
  lx[i]=bestX;ly[i]=bestY;lw[i]=w;
  epaper.drawLine(x,y,bestX+w/2,bestY+5,color(p));
 }
 for(int i=0;i<count;i++){
  epaper.fillRect(lx[i],ly[i],lw[i],10,TFT_WHITE);
  text(lx[i]+2,ly[i]+1,planes[i].name.substring(0,9));
 }
 epaper.fillCircle(cx,cy,4,TFT_BLACK);text(cx-9,cy+10,"HAM");text(415,86,String(count)+" aircraft shown",2);text(415,115,"Nearest aircraft / airborne only");const int callX=428,typeX=494,distX=542,altX=590,speedX=650;
 text(callX,141,"CALLSIGN");text(typeX,141,"TYPE");text(distX,141,"km");text(altX,141,"m");text(speedX,141,"km/h");epaper.drawLine(412,156,788,156,TFT_BLACK);
 for(int i=0;i<min(count,11);i++){Plane&p=planes[i];int y=168+i*22;epaper.fillRect(415,y,6,10,color(p));text(callX,y,p.name.substring(0,9));text(typeX,y,p.type.substring(0,4));text(distX,y,String(p.km,1));text(altX,y,p.altitude?String((int)lround(p.alt)):"--");text(speedX,y,String((int)lround(p.speed)));}if(!haveData)text(422,225,"No data yet",2);
 text(415,420,"Green <3048 / Blue <7620 / Red >=7620 m");epaper.drawLine(12,447,788,447,TFT_BLACK);if(errorText.length())text(16,455,"STALE: "+errorText+" | last good "+stamp,1,TFT_RED);else text(16,455,"Updated "+stamp+" | 2 min refresh | adsb.fi");epaper.update();}
void showSetupPage(){
 epaper.fillScreen(TFT_WHITE);
 text(24,30,"HAMBURG FLIGHT SCANNER",3);
 text(24,110,"Connect your phone to Wi-Fi:",2);
 text(24,155,"Hamburg-Airtraffic",2);
 text(24,200,"Password: HamburgSetup",2);
 text(24,260,"Open http://192.168.4.1",2);
 text(24,305,"Choose a 2.4 GHz network and enter its password.");
 text(24,335,"Stay connected even if your phone says no internet.");
 text(24,375,"Saved Wi-Fi is retried. Scanner starts when connected.");
 Serial0.println("Refreshing Wi-Fi setup screen");epaper.update();
 Serial0.println("Wi-Fi setup screen refresh completed");
}
void setup(){
 Serial0.begin(115200);Serial0.println("Starting Hamburg scanner");
 Serial0.flush();
 pinMode(4,INPUT_PULLUP);bool forceSetup=digitalRead(4)==LOW;
 WiFi.mode(WIFI_STA);
 WiFi.setAutoReconnect(true);WiFi.setSleep(false);
 wm.setDebugOutput(true);wm.setConnectTimeout(20);wm.setSaveConnectTimeout(20);
 wm.setConfigPortalTimeout(0);wm.setConfigPortalBlocking(false);
 wm.setAPCallback([](WiFiManager*){
  Serial0.println("Wi-Fi setup at http://192.168.4.1");setupPagePending=true;
 });
 // Always offer setup at boot; retain existing credentials.
 wm.startConfigPortal("Hamburg-Airtraffic","HamburgSetup");
 if(!forceSetup)WiFi.begin();
 Serial0.printf("Wi-Fi initialization returned; portal=%d AP IP=%s\n",wm.getConfigPortalActive(),WiFi.softAPIP().toString().c_str());
 epaper.begin();
 showSetupPage();setupPagePending=false;
 setupVisibleUntil=millis()+60000UL;
 offlineSince=millis();
}
void loop(){
 wm.process();
 if(setupPagePending){
  setupPagePending=false;showSetupPage();
  setupVisibleUntil=millis()+60000UL;first=true;
 }
 uint32_t now=millis();int status=WiFi.status();
 if(status!=lastWifiStatus){Serial0.printf("Wi-Fi status=%d\n",status);lastWifiStatus=status;}
 if(status!=WL_CONNECTED){
  if(wasConnected){wasConnected=false;offlineSince=now;Serial0.println("Wi-Fi lost; reconnecting");}
  if(!wm.getConfigPortalActive()){
   if((uint32_t)(now-offlineSince)>=30000UL){Serial0.println("Reopening Wi-Fi setup after 30 seconds offline");wm.startConfigPortal("Hamburg-Airtraffic","HamburgSetup");}
   else if((uint32_t)(now-lastReconnect)>=10000UL){lastReconnect=now;WiFi.reconnect();}
  }
  delay(10);return;
 }
 // Give the user one minute to read and use setup, even if saved Wi-Fi connects.
 if((int32_t)(now-setupVisibleUntil)<0){delay(10);return;}
 if(wm.getConfigPortalActive())wm.stopConfigPortal();
 if(!wasConnected){
  wasConnected=true;
  Serial0.printf("Wi-Fi connected: SSID=%s IP=%s RSSI=%d dBm\n",WiFi.SSID().c_str(),WiFi.localIP().toString().c_str(),WiFi.RSSI());
  configTzTime("CET-1CEST,M3.5.0,M10.5.0/3","pool.ntp.org","time.google.com");first=true;
 }
 if(first||(int32_t)(now-nextPoll)>=0){first=false;bool ok=fetch();Serial0.printf("Traffic fetch %s, %d aircraft: %s\n",ok?"OK":"FAILED",count,errorText.c_str());draw();nextPoll=millis()+120000UL;}
 delay(10);
}