/*
  Project: ESP8266 ESP-12E module, DHT module, LCD1602 I2C module
  Function: Webserver. Getting data from DHT module to the browser
  LCD1602 I2C module pin   ESP8266 (Nodemcu) pin
  SDA   D2
  SCL   D1
  GND   G(GND)
  VCC   VU (5V)
*/
//************************************************************************
#include <ESP8266WiFi.h>//library for ESP8266
#include <LiquidCrystal_I2C.h>//library for LCD1602 I2C
#include <DHT.h>//library for DHT sensor
//************************************************************************
#define DHTPin 14     //DHT module attached to D5 pin of Nodemcu
// Uncomment one of the lines below for whatever DHT sensor type you're using!
#define DHTTYPE DHT11   // DHT 11
//#define DHTTYPE DHT21   // DHT 21 (AM2301)
//#define DHTTYPE DHT22   // DHT 22  (AM2302), AM2321
LiquidCrystal_I2C lcd(0x3F, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE);//initialize the library with the numbers of the interface pins
// Replace with your network credentials
const char* ssid = "TR-2";
const char* password = "AQW112";

WiFiServer server(80);//set web server port number to 80


DHT dht(DHTPin, DHTTYPE);//initialize DHT sensor.

// Temporary variables
static char celsiusTemp[7];
static char fahrenheitTemp[7];
static char humidityTemp[7];

// Client variables
char linebuf[80];
int charcount = 0;

void setup() {
  dht.begin();// initialize the DHT sensor
  lcd.begin(16, 2);//initializing the 16X2 lcd display
  lcd.setBacklightPin(3, POSITIVE); //Switch on the backlight
  lcd.setBacklight(HIGH);
  //Initialize serial and wait for port to open:
  Serial.begin(9600);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for native USB port only
  }

  // We start by connecting to a WiFi network
  Serial.println();
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  WiFi.begin(ssid, password);

  // attempt to connect to Wifi network:
  while (WiFi.status() != WL_CONNECTED) {
    // Connect to WPA/WPA2 network. Change this line if using open or WEP network:
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());

  server.begin();
}

void loop() {
  // listen for incoming clients
  WiFiClient client = server.available();
  if (client) {
    Serial.println("New client");
    memset(linebuf, 0, sizeof(linebuf));
    charcount = 0;
    // an http request ends with a blank line
    boolean currentLineIsBlank = true;
    while (client.connected()) {
      if (client.available()) {
        char c = client.read();
        Serial.write(c);
        //read char by char HTTP request
        linebuf[charcount] = c;
        if (charcount < sizeof(linebuf) - 1) charcount++;
        // if you've gotten to the end of the line (received a newline
        // character) and the line is blank, the http request has ended,
        // so you can send a reply
        if (c == '\n' && currentLineIsBlank) {
          // Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)
          float h = dht.readHumidity();
          // Read temperature as Celsius (the default)
          float t = dht.readTemperature();
          // Read temperature as Fahrenheit (isFahrenheit = true)
          float f = dht.readTemperature(true);
          // Check if any reads failed and exit early (to try again).
          lcd.setCursor(0, 0);                       //setting display position
  lcd.print("Temp: "); lcd.print(celsiusTemp); lcd.print(" *C");
  lcd.setCursor(0, 1);                       //setting display position
  //lcd.print("Temp: ");lcd.print(fahrenheitTemp);lcd.print(" *F\t");
  lcd.print("Hum: "); lcd.print(humidityTemp); lcd.print(" %");
          if  (isnan(h) || isnan(t) || isnan(f)) {
            Serial.println("Failed to read from DHT sensor!");
            lcd.setCursor(0, 0);                       //setting display position
            lcd.print("Failed to read");
            lcd.setCursor(0, 1);                       //setting display position
            lcd.print("DHT sensor    ");
            return;
          }
          else {
            // Computes temperature values in Celsius + Fahrenheit and Humidity
            float hic = dht.computeHeatIndex(t, h, false);
            dtostrf(hic, 6, 2, celsiusTemp);
            float hif = dht.computeHeatIndex(f, h);
            dtostrf(hif, 6, 2, fahrenheitTemp);
            dtostrf(h, 6, 2, humidityTemp);
            // You can delete the following Serial.print's, it's just for debugging purposes
            /*Serial.print("Humidity: ");
              Serial.print(h);
              Serial.print(" %\t Temperature: ");
              Serial.print(t);
              Serial.print(" *C ");
              Serial.print(f);
              Serial.print(" *F\t Heat index: ");
              Serial.print(hic);
              Serial.print(" *C ");
              Serial.print(hif);
              Serial.print(" *F");
              Serial.print("Humidity: ");
              Serial.print(h);
              Serial.print(" %\t Temperature: ");
              Serial.print(t);
              Serial.print(" *C ");
              Serial.print(f);
              Serial.print(" *F\t Heat index: ");
              Serial.print(hic);
              Serial.print(" *C ");
              Serial.print(hif);
              Serial.println(" *F");*/
               
          }
          // send a standard http response header
          client.println("HTTP/1.1 200 OK");
          client.println("Content-Type: text/html");
          client.println("Connection: close");  // the connection will be closed after completion of the response
          client.println();
          client.println("<!DOCTYPE HTML><html><head><meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">");
          client.println("<meta http-equiv=\"refresh\" content=\"30\"></head>");
          client.println("<body><div style=\"font-size: 3.5rem;\"><p>ESP8266 ESP-12E - DHT 11 module</p><p>");
          if (atoi(celsiusTemp) >= 25) {
            client.println("<div style=\"color: #FF0000;\">");
          }
          else if (atoi(celsiusTemp) < 25 && atoi(celsiusTemp) >= 5) {
            client.println("<div style=\"color: #00FF21;\">");
          }
          else if (atoi(celsiusTemp) < 5) {
            client.println("<div style=\"color: #0094FF;\">");
          }
          client.println(celsiusTemp);
          client.println("*C</p><p>");
          client.println(fahrenheitTemp);
          client.println("*F</p></div><p>");
          client.println(humidityTemp);
          client.println("%</p></div>");
          client.println("</body></html>");
          break;
        }
        if (c == '\n') {
          // you're starting a new line
          currentLineIsBlank = true;
          memset(linebuf, 0, sizeof(linebuf));
          charcount = 0;
        } else if (c != '\r') {
          // you've gotten a character on the current line
          currentLineIsBlank = false;
        }
      }
    }
    // give the web browser time to receive the data
    delay(1);

    // close the connection:
    client.stop();
    Serial.println("client disconnected");
  }
}