NodeMCU-Based IoT Project: Connecting Color Sensor

#include <SoftwareSerial.h>
SoftwareSerial mySerial(12, 13); // RX, TX

#include <ESP8266WiFi.h>          //https://github.com/esp8266/Arduino
#include <DNSServer.h>
#include <ESP8266WebServer.h>
#include "WiFiManager.h"          //https://github.com/tzapu/WiFiManager
#include <WiFiClientSecure.h>
int fcolor=0;//1->red,2->blue,3->green
int count=0,i,m,j,k;
int red=0,green=0,blue=0;;
const int s0 = D4;  
const int s1 = D5;  
const int s2 = D6;  
const int s3 = D7;  
const int out = D8; 



//////////////////////////////////////// ALL DECLARATIONS for CLOUD //////////////////////////////
const char* host = "api.thingsai.io";                                 // OR host = devapi2.thethingscloud.com
const char* post_url = "/devices/deviceData";       // OR /api/v2/thingscloud2/_table/data_ac
const char* time_server = "baas.thethingscloud.com";             //this is to convert timestamp
const int httpPort = 80;
const int httpsPort = 443;
const char*  server = "api.thingsai.io";  // Server URL

char timestamp[10];

WiFiClient client;


/////////////////////////////////////////////////////////////////////////////////////////////////////////
void configModeCallback (WiFiManager *myWiFiManager) 
{
  Serial.println("Entered config mode");             //*-*-*-*-*-*-*-*-*-*-*-*-*-*if control enters this function then net is not connected
  Serial.println(WiFi.softAPIP());                  // "WiFi.softAPIP() is for AP" , "WiFi.localIP() is for STA",
                                                                
  Serial.println(myWiFiManager->getConfigPortalSSID());             //if you used auto generated SSID, print it
}
/////////////////////////////////////// TIMESTAMP CALCULATION function///////////////////////////////////////
int GiveMeTimestamp()
{
  unsigned long timeout = millis();

  while (client.available() == 0)
  {
    if (millis() - timeout > 50000)
    {
      client.stop();
      return 0;
    }
  }

while (client.available())
      {
        String line = client.readStringUntil('\r');                    //indexOf() is a funtion to search for smthng , it returns -1 if not found
        int pos = line.indexOf("\"timestamp\"");                       //search for "\"timestamp\"" from beginning of response got and copy all data after that , it'll be your timestamp
        if (pos >= 0)                                                     
        {
          int j = 0;
          for(j=0;j<10;j++)
          {
            timestamp[j] = line[pos + 12 + j];
          }
        }
      }
}  
////////////////////////////////////////////////////////////////////////////////////////////////////////

void setup() 
{
  Serial.begin(115200);     //(19200,SERIAL_8E1) - data size = 8 bits , parity = Even , stop bit =  1bit
  mySerial.begin(115200);
  WiFiManager wifiManager;
 
  wifiManager.setAPCallback(configModeCallback);
                                                                                                    
  if(!wifiManager.autoConnect("sattu","Babayaga"))                   //wifiManager.autoConnect("AP-NAME", "AP-PASSWORD"); (OR) wifiManager.autoConnect("AP-NAME"); only ID no password (OR) wifiManager.autoConnect(); this will generate a ID by itself
  {
    Serial.println("failed to connect and hit timeout");     //control comes here after long time of creating Access point "NodeMCU" by NodeMCU and still it has not connected
    //reset and try again, or maybe put it to deep sleep
    ESP.reset();
    delay(1000);
  } 

  //if you come here you have connected to the WiFi
  Serial.println("connected...yeey :");
 pinMode(s0, OUTPUT);  
  pinMode(s1, OUTPUT);  
  pinMode(s2, OUTPUT);  
  pinMode(s3, OUTPUT);  
  pinMode(out, INPUT);  
   digitalWrite(s0, HIGH);  
  digitalWrite(s1, HIGH); 
}

void loop() 
{
  
{
 
  
/////////////////////////////////////// SEND THE QUERY AND RECEIVE THE RESPONSE///////////////////////  



        

          

  Serial.print("connecting to ");
  Serial.println(host);                          //defined upside :- host = devapi2.thethingscloud.com or 139.59.26.117

///////////////////////////////////// TIMESTAMP CODE SNIPPET /////////////////////////
Serial.println("inside get timestamp\n");
  if (!client.connect(time_server, httpPort)) 
  {
    return;                                                        //*-*-*-*-*-*-*-*-*-*
  }

  client.println("GET /api/timestamp HTTP/1.1");                            //Whats this part doing, i didnt get
  client.println("Host: baas.thethingscloud.com");
  client.println("Cache-Control: no-cache");
  client.println("Postman-Token: ea3c18c6-09ba-d049-ccf3-369a22a284b8");
  client.println();

GiveMeTimestamp();                        //it'll call the function which will get the timestamp response from the server
Serial.println("timestamp receieved");
Serial.println(timestamp);
///////////////////////////////////////////////////////////////////////////////
digitalWrite(s2, LOW);  
  digitalWrite(s3, LOW);  
  //count OUT, pRed, RED  
  red = pulseIn(out, digitalRead(out) == HIGH ? LOW : HIGH);  
  digitalWrite(s3, HIGH);  
  //count OUT, pBLUE, BLUE  
  blue = pulseIn(out, digitalRead(out) == HIGH ? LOW : HIGH);  
  digitalWrite(s2, HIGH);  
  //count OUT, pGreen, GREEN  
  green = pulseIn(out, digitalRead(out) == HIGH ? LOW : HIGH);  
//////////////////////////////////////////////////////////////////
  Serial.print("R Intensity:");  
  Serial.print(red, DEC);  
  Serial.print(" G Intensity: ");  
  Serial.print(green, DEC);  
  Serial.print(" B Intensity : ");  
  Serial.print(blue, DEC);  
  /////////////////////////////////////////////////
  if (red < blue && red < green && red < 20)
  {  
   Serial.println(" - (Red Color)"); 
   fcolor = 1; 
 
  }  
 
  else if (blue < red && blue < green)   
  {  
   Serial.println(" - (Blue Color)"); 
   fcolor = 2; 
 
  }  
 
  else if (green < red && green < blue)  
  {  
   Serial.println(" - (Green Color)");  
   fcolor = 3;
 
  }  
  else{
  Serial.println();  
  }
  delay(300);   
  ///////////////////////////////////////////////////////
  Serial.println("inside ThingsCloudPost");

 
  String PostValue = "{\"device_id\":  61121695940, \"slave_id\": 2";
         PostValue = PostValue + ",\"dts\":" +timestamp;
   PostValue = PostValue +",\"data\":{\"color\":" + fcolor +"}"+"}";
  
  
  Serial.println(PostValue);

/* create an instance of WiFiClientSecure */
    WiFiClientSecure client;
    
    Serial.println("Connect to server via port 443");
    if (!client.connect(server, 443)){
        Serial.println("Connection failed!");
    } else {
        Serial.println("Connected to server!");
        /* create HTTP request */

        client.println("POST /devices/deviceData HTTP/1.1");
        client.println("Host: api.thingsai.io");
        //client.println("Connection: close");
        client.println("Content-Type: application/json");
        client.println("cache-control: no-cache");
        client.println("Authorization: Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.IjVhMzBkZDFkN2QwYjNhNGQzODkwYzQ4OSI.kaY6OMj5cYlWNqC2PNTkXs9PKy6_m9tdW5AG7ajfVlY");
        client.print("Content-Length: ");
        client.println(PostValue.length());
        client.println();
        client.println(PostValue);
//////////////////////////////////POSTING the data on to the cloud is done and now get the response form cloud server//////////////////
 Serial.print("Waiting for response ");
        while (!client.available()){
            delay(50); //
            Serial.print(".");
        }  
        /* if data is available then receive and print to Terminal */
        while (client.available()) {
            char c = client.read();
            Serial.write(c);
        }

        /* if the server disconnected, stop the client */
        if (!client.connected()) {
            Serial.println();
            Serial.println("Server disconnected");
            client.stop();
        }
    }
Serial.println("//////////////////////    THE END     /////////////////////");
fcolor = 0;
delay(3000);
}
}