#include <ESP8266WiFi.h>
#include <ESPSendMail.h>

#define TRIGGER_PIN     16
#define ECHO_PIN        5

#define EMPTY_TANK      30 //cm

#define WIFINAME "your_wifi_name"
#define WIFIPWD "your_wifi_password"
#define MAILSERVER "your_mailserver"
#define MAILUSERNAME "your_mailserver_username"
#define MAILUSERPWD "our_mailserver_password"

// 20 Liter Füllmenge (Wasser) = 5cm
// 1 Liter Füllmenge (Wasser) = 2cm


float AVG_WATER = 0.00;
uint8_t AVG_WATER_CNT = 0;

WiFiClientSecure client;

void setup()
{

  Serial.begin(9600);

  // Connect to WiFi network
  Serial.print("Connecting to ");
  Serial.println(WIFINAME);

  WiFi.begin(WIFINAME, WIFIPWD);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("My IP address: ");
  Serial.println(WiFi.localIP());
  delay(1000);


  pinMode(TRIGGER_PIN,OUTPUT);
  pinMode(ECHO_PIN,INPUT);
  pinMode(ECHO_PIN, INPUT_PULLUP);


  ESPSendMail SendMail(MAILSERVER,MAILUSERNAME,MAILUSERPWD, &client);
  SendMail.From = "examples@gmail.com"; //put your address here
  SendMail.DisplayFrom = "From_Name"; //put display name here
  SendMail.To = "testtest@gmail.com"; //recipient address
  SendMail.Subject = "Test e-mail"; //subject
  SendMail.ClearMessage();
  SendMail.AddMessageLine("First line of message"); //lines of message
  SendMail.AddMessageLine("Second line");

  SendMail.Send();


}

void loop() {

  for ( uint8_t x = 0 ; x < 30 ; x++ )
  {
    AVG_WATER += GetDistance();
    AVG_WATER_CNT++;
    delay(500);
  }
  AVG_WATER /= AVG_WATER_CNT;
  AVG_WATER_CNT = 0;

 Serial.println(AVG_WATER);

}

float GetDistance()
{
  float lDistance = 0;
  float lLength = 0;

  digitalWrite(TRIGGER_PIN, LOW);
  delayMicroseconds(5);
  digitalWrite(TRIGGER_PIN,HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIGGER_PIN,LOW);

  lLength = pulseIn(ECHO_PIN,HIGH);
  lDistance = (lLength / 2) * 0.03432;

  return EMPTY_TANK - (lDistance);
}