#include <SPI.h>
#include <Ethernet2.h>
#include <ICMPPing.h>

#include <ESP8266WiFi.h>
#include <ESPAsyncTCP.h>
#include <ESPAsyncWebServer.h>
#include <FS.h>

#define TTL 64
#define CS_PIN 16 // SPI Chip Select pin 
#define LED_ON  LOW
#define LED_OFF HIGH

#define setLocalIP    1
#define setGatewayIP  2
#define setSubnet     3
#define passIP        4
#define LINK_DOWN     0
#define LINK_UP       1

float VBmin = 3.30;
float VBmax = 4.10;


byte mac[] = { 0x36, 0xF2, 0xCC, 0xF2, 0xE5, 0xC0 };
IPAddress pingAddr(192, 168, 1, 1);                  // ip address to ping
IPAddress destGateway(192, 168, 1, 1);

const char* ssid = "SERVER_SLT";
const char* password = "admin8266";

bool submit = false;
bool Rsubmit = false;
bool initPing = false;
bool eLink;
byte idx = 0;
byte idy = 0;
bool updt;
//bool clearReply = false;
String nullStr = "";
bool btnGetIP = false;
bool btnSetIP = false;
byte IPSW;
bool repeatPing;
bool initPingRepeat;
String pingResponse;
byte scs_cnt;
byte pktLoss;
byte pLoss;
String endStr = "% loss)";
String null_IP = "xxx.xxx.xxx.xxx" ;
unsigned int pTime[4] = {0,0,0,0};
unsigned int minT;
unsigned int maxT;
unsigned int avgT;

 byte bat; // temp var

// Create AsyncWebServer object on port 80
AsyncWebServer server(80);
AsyncEventSource events("/events"); // new

// new user variables
unsigned long lastTime = 0;  
unsigned long timerDelay = 2000;  // send readings timer
char buffer [256];

IPAddress local_IP(192,168,10,1);  
IPAddress gateway(192,168,10,1);  
IPAddress subnet(255,255,255,0);  
SOCKET pingSocket = 1;
ICMPPing ping(pingSocket, (uint16_t)random(1, 1023), TTL);
ICMPEchoReply echoReply;


void setup(){
  pinMode(LED_BUILTIN, OUTPUT);
  digitalWrite(LED_BUILTIN, LED_OFF);
  Serial.begin(9600);
  Serial.println("---Serial Monitor---");
  
  w5500.init(CS_PIN);
  w5500.setRCR(0);
  w5500.setPTimer(40);
  repeatPing = 1;
  updt = true; 
  // Initialize SPIFFS
  if(!SPIFFS.begin()){
    Serial.println("An Error has occurred while mounting SPIFFS");
    return;
  }

// Connect to Wi-Fi
  WiFi.softAPConfig(local_IP, gateway, subnet);//
  WiFi.softAP(ssid, password); //
  delay(500);
  digitalWrite(LED_BUILTIN, LOW);
// Route for root / web page
  server.on("/", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/esp8266slt.html", String(), false, processor);
  });

// Route to load style.css file
  server.on("/style.css", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/style.css", "text/css");
  });

// Route to load script.js file
  server.on("/script.js", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/script.js", "text/javascript");
  });

// Route to load image file
  server.on("/sltlogo.jpg", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/sltlogo.jpg", "image/png");
  });

// Route to load image file
  server.on("/EthConnected.png", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/EthConnected.png", "image/png");
  }); 

// Route to load image file
  server.on("/EthDisconnected.png", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/EthDisconnected.png", "image/png");
  }); 

// Route to load image file
  server.on("/EthBussy.png", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/EthBussy.png", "image/png");
  });  

// Route to load image file
  server.on("/WIFI.jpg", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/WIFI.jpg", "image/jpg");
  }); 

// Route to load image file
  server.on("/FULL.jpg", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/FULL.jpg", "image/jpg");
  }); 

// Route to load image file
  server.on("/HIGH.jpg", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/HIGH.jpg", "image/jpg");
  });

// Route to load image file
  server.on("/LOW.jpg", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/LOW.jpg", "image/jpg");
  });

// Route to load image file
  server.on("/EMT.jpg", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/EMT.jpg", "image/jpg");
  });

// Route to load image file
  server.on("/CHRG.jpg", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/CHRG.jpg", "image/jpg");
  });

// Route to load image file
  server.on("/BAT.jpg", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(SPIFFS, "/BAT.jpg", "image/jpg");
  });

  server.on("/get_IP", HTTP_GET, [](AsyncWebServerRequest *request){  
    btnGetIP = true;
    btnSetIP = true;
    updt = true;  
    request->send(SPIFFS, "/esp8266slt.html", String(), false, processor);
  });


  server.on("/action", HTTP_GET, [](AsyncWebServerRequest *request){   
      pingAddr[0] = request->getParam("IP0")-> value().toInt() ;
      pingAddr[1] = request->getParam("IP1")-> value().toInt() ;
      pingAddr[2] = request->getParam("IP2")-> value().toInt() ;
      pingAddr[3] = request->getParam("IP3")-> value().toInt() ;
      submit = 1;
      IPSW = setLocalIP;         
    request->send(SPIFFS, "/esp8266slt.html", String(), false, processor);
  });

  server.on("/action_2", HTTP_GET, [](AsyncWebServerRequest *request){   
    repeatPing = !repeatPing;
      pingAddr[0] = request->getParam("IP0")-> value().toInt() ;
      pingAddr[1] = request->getParam("IP1")-> value().toInt() ;
      pingAddr[2] = request->getParam("IP2")-> value().toInt() ;
      pingAddr[3] = request->getParam("IP3")-> value().toInt() ;
      Rsubmit = 1;
      IPSW = setLocalIP; 
      idy = 0;
      updt = true;         
    request->send(SPIFFS, "/esp8266slt.html", String(), false, processor);
  });
  
  // Start server
  server.addHandler(&events); // new
  server.begin();
}

void loop(){
  handleWDT();

  handlePing();
  handleRepeatPing();

  handleBtnFn();
  handleDSPIP();
  handleEthIcon();
  handleBkgrndPrcs();
  
  
}

////////
void handleBtnFn(){
  
  if(btnSetIP){
    IPSW = setLocalIP;
    btnSetIP = false;
    idx = 0;
  }
   
  if(initPing){
    lastTime = millis();
    idx = 1;
    updt = false; 
    initPing = false;
    scs_cnt = 0;
    minT = 5000;
    maxT = 0;
    avgT = 0;
  }

  if(initPingRepeat){
    lastTime = millis();
    idy = 1;
    updt = false; 
    initPingRepeat = 0;
  }

  delay(100);
}

void handleDSPIP(){
  if(IPSW == setLocalIP){
    events.send(" ",NULL);
    delay(500);
    events.send(strLocalIP().c_str(),"LCIP");   
    IPSW ++ ;
  }else if(IPSW == setGatewayIP){
    events.send(strGatewayIP().c_str(),"GWIP");
    IPSW ++ ;
  }else if(IPSW == setSubnet){
    events.send(strSubnet().c_str(),"SNM");
    IPSW ++ ;
      if(submit) initPing = true;  ////
      if(Rsubmit && !repeatPing) initPingRepeat = true;  //// repeatPing
    submit = 0;
    Rsubmit=0;
  }
    if(Ethernet.linkStatus() == LinkOFF) delay(600);
}

void handlePing(){
  if( (millis() - lastTime > timerDelay) && idx){  
    
    if (idx == 1) {
      events.send("",NULL);
      delay(100);
    }else if (idx == 2) {
      events.send(pingEthernet(pingAddr).c_str(),"R1");
    }else if (idx == 3) {
      events.send(pingEthernet(pingAddr).c_str(),"R2");
    }else if (idx == 4) { 
      events.send(pingEthernet(pingAddr).c_str(),"R3");
    }else if (idx == 5) {
      events.send(pingEthernet(pingAddr).c_str(),"R4");
    }else if (idx == 6) {    
        if(Ethernet.linkStatus() == LinkOFF){
          events.send("Please Check Ethernet Link","S1"); 
        }else{
          events.send("Ping Statistics:","S1"); 
          delay(100);
          events.send((pingStat() + endStr).c_str(),"S2");
          delay(100); 
        }
        
        if(scs_cnt){
          events.send("Approximate Round Trip:","S3");
          delay(100);
          events.send(rTrip().c_str(),"S4");
          delay(100);
        }
    }else{
      events.send("",NULL,millis());
      idx = 0;
      updt = true; 
    }
    
      if(idx > 0 && idx < 7)idx++;
      lastTime = millis();    
  }
}

void handleRepeatPing(){
  if( (millis() - lastTime > timerDelay) && idy){  
    handleWDT(); 
    if(idy == 1){
      events.send("",NULL);
      delay(100); 
      updateWAPSN();
      chngBtnClr();
      updateBTRYL();          
    }else if(idy == 2){
      events.send(pingEthernet(pingAddr).c_str(),"R1");          
    }else if (idy == 3) {
      events.send(pingEthernet(pingAddr).c_str(),"R2");
    }else if (idy == 4) { 
      events.send(pingEthernet(pingAddr).c_str(),"R3");     
    }else if (idy == 5) {
      events.send(pingEthernet(pingAddr).c_str(),"R4");     
    }else if (idy == 6) {
      events.send("","R1");  delay(100);
      events.send("","R2");  delay(100);
      events.send("","R3");  delay(100);
      events.send("","R4");  delay(100);   
    }else{
      idy = 1;
    }

    if(idy>0 && idy<7) idy++;
    lastTime = millis(); 

    delay(1000);     
  }
}
///////////
String pingStat(){
    pktLoss = 4 - scs_cnt;
    pLoss = pktLoss*25;
   
    sprintf(buffer,
      "Packets: Sent=4, Received=%d, Lost=%d (%d",
       scs_cnt,
       pktLoss,
       pLoss
    );
    return buffer;
}

unsigned int tMin(){
  for(byte n = 0; n < scs_cnt; n++){
    minT = min(minT,pTime[n] );
  }
  return minT;
}

unsigned int tMax(){
  for(byte n = 0; n < scs_cnt; n++){
    maxT = max(maxT,pTime[n] );
  }
  return maxT;
}

unsigned int tAvg(){
  for(byte n = 0; n < scs_cnt; n++){
    avgT += pTime[n];
  }
  avgT = avgT / scs_cnt;
  return avgT; 
}

String rTrip(){
  sprintf(buffer,
    "Min=%d ms, Max=%d ms, Avg=%d ms",
     tMin(),
     tMax(),
     tAvg()
  );  
  return buffer;
}

///////////////////
void handleWDT(){
  ESP.wdtDisable();  
  yield(); 
}

//placeholder
String processor(const String& var){

  if (var == "IP0"){
    if(btnGetIP) return String(destGateway[0]); 
    else return String(pingAddr[0]);    
  }else if (var == "IP1"){
    if(btnGetIP) return String(destGateway[1]); 
    else return String(pingAddr[1]);      
  }else if (var == "IP2"){
    if(btnGetIP) return String(destGateway[2]); 
    else return String(pingAddr[2]);    
  }else if (var == "IP3"){   
    if(btnGetIP){
      btnGetIP = false;
      return String(destGateway[3]); 
    }
    else{
      return String(pingAddr[3]);      
    }
  }else if (var == "PingLoop"){    // Change button label
    if(repeatPing){
      return "REPEAT";
    }else{     
      return "STOP";  
    }       
  }else{
    return String();   
  }
}


String strLocalIP(){
  
  String param_IP;
   
    if(Ethernet.linkStatus() == LinkON){ 
      Ethernet.begin(mac);
      
      for (byte x = 0; x < 4; x++) {
        param_IP += String(Ethernet.localIP()[x], DEC);
        if(x<3)param_IP += ".";
      }      
    }else{
      param_IP = "xxx.xxx.xxx.xxx" ;
    }
  return param_IP;
}


String strGatewayIP(){
  
  String param_IP;
   
    if(Ethernet.linkStatus() == LinkON){ 
      destGateway = Ethernet.gatewayIP();         
      for (byte x = 0; x < 4; x++) {
        param_IP += String(Ethernet.gatewayIP()[x], DEC);
        if(x<3)param_IP += ".";
      }       
    }else{
      param_IP = "xxx.xxx.xxx.xxx" ;
    }
  return param_IP;
}

String strSubnet(){
  
  String param_IP;
   
    if(Ethernet.linkStatus() == LinkON){      
      for (byte x = 0; x < 4; x++) {
        param_IP += String(Ethernet.subnetMask()[x], DEC);
        if(x<3)param_IP += ".";
      }      
    }else{
      param_IP = "xxx.xxx.xxx.xxx" ;
    }

  return param_IP;
}

///////////////////

////////////////////////////////////// 

String pingEthernet(IPAddress pingIP){
   
  if(Ethernet.linkStatus() == LinkON){
      eLink = LinkON;
      // // Ethernet.begin(mac);
      echoReply = ping(pingIP, 1); 
      
      if (echoReply.status == SUCCESS){ 
        pTime[scs_cnt] = millis() - echoReply.data.time;
             
        sprintf(buffer,
          "Reply from:%d.%d.%d.%d: Bytes=%d Time=%ldms TTL=%d",
          echoReply.addr[0],
          echoReply.addr[1],
          echoReply.addr[2],
          echoReply.addr[3],
          REQ_DATASIZE,
          pTime[scs_cnt],
          echoReply.ttl);
          
        scs_cnt ++;         
      }else{

          String echoReplyStatus;
          
          switch(echoReply.status){
            case SEND_TIMEOUT : echoReplyStatus = "SEND TIMEOUT" ; break;
            case NO_RESPONSE  : echoReplyStatus = "NO RESPONSE"  ; break;
            case BAD_RESPONSE : echoReplyStatus = "BAD RESPONSE" ; break; 
                       default: echoReplyStatus = "UNKNOWN ERR"  ; break;           
          }
          sprintf(buffer, ("Echo request failed: " + echoReplyStatus).c_str()); 
        }
       return buffer;
  }else{
    eLink = LinkOFF;
    return "Failed_to_begin_MAC";
  }            
  
}

/////////

void handleEthIcon(){
  if((millis() - lastTime > timerDelay) && !idx){  
    if(Ethernet.linkStatus() == LinkON){     
       events.send("UP","eth");
       delay(200); 
    } else{
      events.send("DWN","eth");
      delay(200);   
    }
  }
}

void handleBkgrndPrcs(){
  if( (millis() - lastTime > timerDelay) && updt){  
    updateWAPSN();
    chngBtnClr();
    updateBTRYL();
    lastTime = millis(); 
  }
}

// Update the WIFI Access Point Station Number 
void updateWAPSN(){
  String StNum;
  sprintf(buffer, "%d",WiFi.softAPgetStationNum()); 
  StNum = buffer;
  events.send(StNum.c_str(), "StNum");  
  delay(200);
}

// Update Battery Level
void updateBTRYL(){

/*  
  int VB_an = analogRead(A0);
  float V_bat = (3.30*VB_an)/1023.0 ;
  bat = map(V_bat, VBmin, VBmax, 0, 3);
*/ 

  bat = 4; 
  
    switch(bat){
        case 0: events.send("EMT" , "BAT"); delay(100); break;
        case 1: events.send("LOW" , "BAT"); delay(100); break;
        case 2: events.send("HIGH", "BAT"); delay(100); break;
        case 3: events.send("FULL", "BAT"); delay(100); break;
        case 4: events.send("CHRG", "BAT"); delay(100); break;
       default: events.send("BAT" , "BAT"); delay(100); break;
    }   
}

// Change Repeat Ping button color
void chngBtnClr(){
  if(repeatPing){
    events.send("REPEAT", "pingMode");
    delay(200);
  }else{
    events.send("STOP", "pingMode");
    delay(200);
  }  
}