#include <LiquidCrystal_I2C.h>
#include <SPI.h>
#include <SD.h>
#include <TinyGPS++.h>
#include <SoftwareSerial.h>
#include <EEPROM.h>
#include "GravityTDS.h"

// String to hold GPS data
String gpstext;

// GPS Connections
static const int RXPin = 6, TXPin = 5;

// GPS Baud rate (change if required)
static const uint32_t GPSBaud = 9600;

// TinyGPS++ object
TinyGPSPlus gps;

// SoftwareSerial connection to the GPS device
SoftwareSerial ss(RXPin, TXPin);

//I2C LCD
const int chipSelect = 4;

LiquidCrystal_I2C lcd(0x27,16,2);  // set the LCD address to 0x3F for a 16 chars and 2 line display

//Button Push
int run;
int buttonPin;

//TDS
#define TdsSensorPin A1
GravityTDS gravityTds;
float tdsValue = 0;

//TMP
int degreesC = 0;                         //the temperature in Celsius, calculated from the voltage



void setup() {
  
// Start Serial Monitor for debugging
  Serial.begin(115200);

// Start SoftwareSerial
  ss.begin(GPSBaud);
  
//Prep for Button Push
 run = 0; //starts stopped
 buttonPin = 7; //whatever pin your button is plugged into
 pinMode(buttonPin, INPUT_PULLUP);
 pinMode(2,INPUT);

//TDS startup
gravityTds.setPin(TdsSensorPin);
gravityTds.setAref(5.0);  //reference voltage on ADC, default 5.0V on Arduino UNO
gravityTds.setAdcRange(1024);  //1024 for 10bit ADC;4096 for 12bit ADC
gravityTds.begin();  //initialization
  
//LCD startup and SD Check
  lcd.init();
  lcd.clear();         
  lcd.backlight();      // Make sure backlight is on

  if (!SD.begin(chipSelect)) {
   lcd.clear();
   lcd.setCursor(0,0);
   lcd.print("Card failed, or not present");
    // don't do anything more:
    while (1);
  }
  
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("card initialized.");
  delay(1000);
  lcd.clear();
  lcd.print("Finding Sats");
}

void loop() {

while (ss.available() > 0)
    if (gps.encode(ss.read()))

      // See if we have a complete GPS data string
      if (displayInfo() != "0")
      {

        // Get GPS string
        gpstext = displayInfo();
Serial.println(gpstext);

 
degreesC = map(analogRead(A0),0,1023,0,100);  


gravityTds.setTemperature(degreesC);  // set the temperature and execute temperature compensation
gravityTds.update();  //sample and calculate 
tdsValue = gravityTds.getTdsValue();  // then get the value
Serial.print(tdsValue,0);
Serial.println("ppm");
     
 lcd.clear();
 lcd.setCursor(0, 0);                      //set the cursor to the top left position
 lcd.print("Degrees C: ");                 //print a label for the data
 lcd.print(degreesC);                      //print the degrees Celsius

 lcd.setCursor(0, 1);                      //set the cursor to the lower left position
 lcd.print(tdsValue,0);                 //Print a label for the data
 lcd.print("ppm");                      //print the degrees Fahrenheit
 


    
 
//check button pressed, if so enter program condition (inside if statement)
if(digitalRead(buttonPin) == LOW) //functions based off of button pulling input pin LOW
   {
      


File dataFile = SD.open("datalog.txt", FILE_WRITE);

 //if the file is available, write to it:
 if (dataFile) {
   dataFile.print("Degrees C: ");
   dataFile.print(degreesC);
   dataFile.print(",");
   dataFile.print(tdsValue,0);
   dataFile.print("ppm");
   dataFile.print(",");
   dataFile.println(gpstext);
   dataFile.close();
lcd.clear();
lcd.setCursor(0,0);
lcd.print("info saved");
delay(1000);

  }
 // if the file isn't open, pop up an error:
  else {
lcd.clear();
lcd.setCursor(0,0);
lcd.print("error SD");
delay(1000);
}}   
      
      

    delay(1000);
  }}

  
String displayInfo()
{
  // Define empty string to hold output
  gps.encode(ss.read());
  String gpsdata = "";

  // Get latitude and longitude
  if (gps.location.isValid())
  {
    gpsdata = String(gps.location.lat(), 6);
    gpsdata += (",");
    gpsdata += String(gps.location.lng(), 6);
    gpsdata += (",");
  }
  else
  {
    return "0";
  }

  // Return completed string
  return gpsdata;
}