Arduino ESP8266 Wifi AP and client with reconnect

esp_ap.cpp

//A simplified version of work begun by Tzapu and chriscook8
//for saving local WiFi SSID and Passwords to the ESP8266.
//Uses ESP8266 internal memory instead of the problematic EEPROM.
//To input local SSID and Password, connect to WiFi "ESP8266",
//and point your browser to "192.168.4.1".

#include "ESP8266WiFi.h"
#include <ESP8266mDNS.h>
#include <WiFiClient.h>
#include <BlynkSimpleEsp8266.h>

MDNSResponder mdns;
WiFiServer server(80);

char auth[] = "YourAuthToken"; // Blynk token
const char* APssid = "ESP8266"; // Name of access point

String st;
String rsid;
String rpass;
boolean newSSID = false;


void setup() {
  Serial.begin(115200);
  delay(10);
  Serial.println("Startup");

  // if the stored SSID and password connected successfully, exit setup
  if ( testWifi()) {
          Blynk.config(auth);
          return;
      }
  // otherwise, set up an access point to input SSID and password     
  else
      Serial.println("");
      Serial.println("Connect timed out, opening AP"); 
      setupAP();
}

int testWifi(void) {
  int c = 0;
  Serial.println("Waiting for Wifi to connect");  
  while ( c < 20 ) {
    if (WiFi.status() == WL_CONNECTED) {
      Serial.println("WiFi connected.");
      return(1); 
      }      
    delay(500);
    Serial.print(WiFi.status());    
    c++;
  }
  return(0);
} 

void launchWeb(int webtype) {
    Serial.println("");
    Serial.println("WiFi connected");
    Serial.println(WiFi.localIP());
    Serial.println(WiFi.softAPIP());
   /* if (!mdns.begin("esp8266", WiFi.localIP())) {
      Serial.println("Error setting up MDNS responder!");
      while(1) { 
        delay(1000);
      }
    }
    Serial.println("mDNS responder started");
    */
    // Start the server
    server.begin();
    Serial.println("Server started");   
    int b = 20;
    int c = 0;
    while(b == 20) { 
       b = mdns1(webtype);

       //If a new SSID and Password were sent, close the AP, and connect to local WIFI
       if (newSSID == true){
          newSSID = false;

          //convert SSID and Password sting to char
          char ssid[rsid.length()];
          rsid.toCharArray(ssid, rsid.length());         
          char pass[rpass.length()];
          rpass.toCharArray(pass, rpass.length());

          Serial.println("Connecting to local Wifi");
          delay(500);
          WiFi.softAPdisconnect(true);
          delay(500);
          WiFi.mode(WIFI_STA);
          WiFi.begin(ssid,pass);
          delay(1000);
          if ( testWifi()) {
            Blynk.config(auth);
            return;
          }

         else{
            Serial.println("");
            Serial.println("New SSID or Password failed. Reconnect to server, and try again.");
            setupAP();
            return;
         }
       }
     }
}


void setupAP(void) {
  
  WiFi.mode(WIFI_STA);
  WiFi.disconnect();
  delay(100);
  int n = WiFi.scanNetworks();
  Serial.println("scan done");
  if (n == 0)
    Serial.println("no networks found");
  else
  {
    Serial.print(n);
    Serial.println(" networks found");
  }
  Serial.println(""); 
  st = "<ul>";
  for (int i = 0; i < n; ++i)
    {
      // Print SSID and RSSI for each network found
      st += "<li>";
      st +=i + 1;
      st += ": ";
      st += WiFi.SSID(i);
      st += " (";
      st += WiFi.RSSI(i);
      st += ")";
      st += (WiFi.encryptionType(i) == ENC_TYPE_NONE)?" ":"*";
      st += "</li>";
    }
  st += "</ul>";
  delay(100);
  WiFi.softAP(APssid);
  Serial.println("softAP");
  Serial.println("");
  launchWeb(1);
}


String urldecode(const char *src){ //fix encoding
  String decoded = "";
    char a, b;
    
  while (*src) {     
    if ((*src == '%') && ((a = src[1]) && (b = src[2])) && (isxdigit(a) && isxdigit(b))) {      
      if (a >= 'a')
        a -= 'a'-'A';       
      if (a >= 'A')                
        a -= ('A' - 10);                   
      else               
        a -= '0';                  
      if (b >= 'a')                
        b -= 'a'-'A';           
      if (b >= 'A')                
        b -= ('A' - 10);            
      else                
        b -= '0';                        
      decoded += char(16*a+b);            
      src+=3;        
    } 
    else if (*src == '+') {
      decoded += ' ';           
      *src++;       
    }  
    else {
      decoded += *src;           
      *src++;        
    }    
  }
  decoded += '\0';        
  return decoded;
}


int mdns1(int webtype){
  // Check for any mDNS queries and send responses
  //mdns.update();
  
  // Check if a client has connected
  WiFiClient client = server.available();
  if (!client) {
    return(20);
  }
  Serial.println("");
  Serial.println("New client");

  // Wait for data from client to become available
  while(client.connected() && !client.available()){
    delay(1);
   }
  
  // Read the first line of HTTP request
  String req = client.readStringUntil('\r');
  
  // First line of HTTP request looks like "GET /path HTTP/1.1"
  // Retrieve the "/path" part by finding the spaces
  int addr_start = req.indexOf(' ');
  int addr_end = req.indexOf(' ', addr_start + 1);
  if (addr_start == -1 || addr_end == -1) {
    Serial.print("Invalid request: ");
    Serial.println(req);
    return(20);
   }
  req = req.substring(addr_start + 1, addr_end);
  Serial.print("Request: ");
  Serial.println(req);
  client.flush(); 
  String s;
  if ( webtype == 1 ) {
      if (req == "/")
      {
        IPAddress ip = WiFi.softAPIP();
        String ipStr = String(ip[0]) + '.' + String(ip[1]) + '.' + String(ip[2]) + '.' + String(ip[3]);
        s = "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n<!DOCTYPE HTML>\r\n<html>Hello from ESP8266 at ";
        s += ipStr;
        s += "<p>";
        s += st;
        s += "<form method='get' action='a'><label>SSID: </label><input name='ssid' length=32><input name='pass' length=64><input type='submit'></form>";
        s += "</html>\r\n\r\n";
        Serial.println("Sending 200");
      }
      else if ( req.startsWith("/a?ssid=") ) {

        newSSID = true;
        String qsid; //WiFi SSID 
        qsid = urldecode(req.substring(8,req.indexOf('&')).c_str()); //correct coding for spaces as "+"
        Serial.println(qsid);
        Serial.println("");
        rsid = qsid;
        
        String qpass; //Wifi Password
        qpass = urldecode(req.substring(req.lastIndexOf('=')+1).c_str());//correct for coding spaces as "+"
        Serial.println(qpass);
        Serial.println("");
        rpass = qpass;
 
        s = "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n<!DOCTYPE HTML>\r\n<html>Hello from ESP8266 ";
        s += "<p> New SSID and Password accepted</html>\r\n\r\n"; 
      }
      else
      {
        s = "HTTP/1.1 404 Not Found\r\n\r\n";
        Serial.println("Sending 404");
      }
  } 
  else
  {
      if (req == "/")
      {
        s = "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n<!DOCTYPE HTML>\r\n<html>Hello from ESP8266";
        s += "<p>";
        s += "</html>\r\n\r\n";
        Serial.println("Sending 200");
      }
      else
      {
        s = "HTTP/1.1 404 Not Found\r\n\r\n";
        Serial.println("Sending 404");
      }       
  }
  client.print(s);
  Serial.println("Done with client");
  return(20);
}


void loop() {
  // put your main code here, to run repeatedly:

  Blynk.run();
}