#include <Wire.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BME680.h>
#include <Adafruit_GFX.h>
#include <Adafruit_ILI9341.h>
#include <SPI.h>
//#include <SD.h>

//TFT LCD Setup
#define TFT_CS 10
#define TFT_DC 9

#define SCREEN_WIDTH 320
#define SCREEN_HEIGHT 240

//BME680 Setup
Adafruit_BME680 bme;

const int downButtonPin = 5;
const int selectButtonPin = 6;
const int clearButtonPin = 7;

int cursorPosition = 0;
//go down the list of options
boolean buttonStateDown = LOW;
boolean lastButtonStateDown = LOW;
boolean currentButtonStateDown = LOW;
//select an menu option
boolean buttonStateSelect = LOW;
boolean lastButtonStateSelect = LOW;
boolean currentButtonStateSelect = LOW;
//clear button, will reset the menu back to the start
boolean buttonStateClear = LOW;
boolean lastButtonStateClear = LOW;
boolean currentButtonStateClear = LOW;

// measure the debouncing time of a button push
// unsigned long as they have a larger size, in milliseconds the numbers can get quite large
unsigned long lastDebounceTime = 0; //takes snapshot of time when button is pressed
unsigned long debounceDelay = 200; //delay time in milliseconds

//boolean menuSelected = false; 

// SD Card Setup
const int chipSelect = 4;  // chip select pin for the SD card module

String Temperature, Pressure, Humidity, Gas, Data; //for the SDcard File

//File dataFile;  // File object to store sensor data

Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC);

void setup() {
  //setup the LCD
  tft.begin();
  tft.setRotation(3); // adjust the rotation of screen
  tft.fillScreen(ILI9341_BLACK); //used to reset the screen

  //set button pins as inputs
  pinMode(downButtonPin, INPUT_PULLUP);
  pinMode(selectButtonPin, INPUT_PULLUP);
  pinMode(clearButtonPin, INPUT_PULLUP);

  bme.setTemperatureOversampling(BME680_OS_8X);
  bme.setPressureOversampling(BME680_OS_8X);
  bme.setHumidityOversampling(BME680_OS_2X);
  bme.setGasHeater(320,150);

  /*if (!bme.begin(0x76)) {
    Serial.println("Could not find a valid BME680 sensor, check wiring!");
    while (1);
  }*/

    // SD card initialization
  /*if (!SD.begin(chipSelect)) {
    Serial.println("SD card initialization failed!");
    while (1);
  } 
  dataFile = SD.open("datalog.txt", FILE_WRITE);
  if (dataFile){
    dataFile.println("Temperature(°C), Pressure(Pa), Gas(ohms), Humidity(%) \r\n");
    dataFile.close();
  }
  else {
    Serial.println("error opening data.txt");
  }
  */
  // Set the temperature, pressure and humidity and gas resistance oversampling
}

void loop() {
  Serial.begin(9600);
  //create an arrow system
  tft.setTextColor(ILI9341_WHITE);
  tft.setTextSize(3);
  tft.setCursor(14, 0);                   // Menu displayed on the LCD.
  tft.println("Temperature");
  tft.println(" Pressure");
  tft.println(" Gas");
  tft.println(" Humidity");       //menu selection going down
  tft.setCursor(270, cursorPosition); //changes cursor position each time the button is pressed
  tft.print(">");

  //wait for an input
  currentButtonStateDown = digitalRead(downButtonPin);
  currentButtonStateSelect = digitalRead(selectButtonPin);
  currentButtonStateClear = digitalRead(clearButtonPin);

  if (currentButtonStateDown != lastButtonStateDown || currentButtonStateSelect != lastButtonStateSelect || currentButtonStateClear != lastButtonStateClear)
  // If there is a button push on any of the buttons, the following routine runs to check if it was a valid press:
  {
    lastDebounceTime = millis();      // lastDebounceTime is set equal to the running millis() function.
  }

  if ((millis() - lastDebounceTime) > debounceDelay)
  /* If the lastDebounceTime (aka. the "snapshot" time) minus the running millis() function is higher than the set debounce  delay, the following routine
 below runs and checks which button was pushed:*/
  {
    //down button press
    if (currentButtonStateDown != buttonStateDown)
    {
      buttonStateDown = currentButtonStateDown;

      if (buttonStateDown == LOW)
      {
        Serial.println("Down Button Pressed");
        cursorPosition = cursorPosition + 28; //for ours will have arrow go down the list
      }
      if (cursorPosition > 84) { //resets menu, goes back to top of list
        cursorPosition = 0;
      }
      delay(300);
      tft.fillScreen(ILI9341_BLACK);
    }
    //select button press
    if (currentButtonStateSelect != buttonStateSelect)
    {
      buttonStateSelect = currentButtonStateSelect;

      if (buttonStateSelect == LOW) {
        if (cursorPosition == 0){
          Serial.println("Enter Pressed");
          tft.fillScreen(ILI9341_BLACK);
          tft.setCursor(14, 10);
          tft.println("");
          tft.println("TEMPERATURE : ");
          tft.print(bme.temperature);
          tft.print(" *C");
          delay(1000);
          //logSensorData("Temperature", bme.temperature);
          //menuSelected = true;
          //logSensorData("Temperature", bme.temperature);
        } else if (cursorPosition == 28) {
        //clear LCD, set cursor
        //print the option
          Serial.println("Enter Pressed again");
          tft.fillScreen(ILI9341_BLACK);
          tft.setCursor(14, 10);
          tft.println("");
          tft.println("PRESSURE : ");
          tft.print(bme.pressure);
          tft.print(" Pa");
          delay(1000);
          //logSensorData("Pressure", bme.pressure);
          //menuSelected = true;
        } else if (cursorPosition == 56) {
        //clear LCD, set cursor
        //print the option
          Serial.println("Enter Pressed for the 3rd time");
          tft.fillScreen(ILI9341_BLACK);
          tft.setCursor(14, 10);
          tft.println("");
          tft.println("GAS : ");
          tft.print(bme.gas_resistance);
          tft.print(" Ohms");
          delay(1000);
          //logSensorData("Gas", bme.gas_resistance);
          //menuSelected = true;
        } else if (cursorPosition == 84) {
        //clear LCD, set cursor
        //print the option
          Serial.println("Enter Pressed for 4th time");
          tft.fillScreen(ILI9341_BLACK);
          tft.setCursor(10, 10);
          tft.println("");
          tft.println("Humidity : ");
          tft.print(bme.humidity);
          tft.print(" %");
          delay(1000);
          //logSensorData("Humidity", bme.humidity);
          //menuSelected = true;
         }
      //clear the LCD
      tft.fillScreen(ILI9341_BLACK);
    }
  }

    // CLEAR BUTTON PRESS
    if (currentButtonStateClear != buttonStateClear)
    {
      buttonStateClear = currentButtonStateClear;

      if (buttonStateClear == LOW)
      {
        //clear LCD, set the cursor
        Serial.println("Cleared Menu");
        tft.fillScreen(ILI9341_BLACK);
        tft.setCursor(10, 10);
        tft.println("MENU IS CLEARED");
        delay(2000);
        cursorPosition = 0;
        //menuSelected = false;
      }
      tft.fillScreen(ILI9341_BLACK);
    }
  }

  // After a button is pushed and the count recorded, all the states reset back to LOW for the data to be processed correctly.
  lastButtonStateDown = currentButtonStateDown;       // resets the down button state to LOW
  lastButtonStateSelect = currentButtonStateSelect;   // resets the enter button state to LOW
  lastButtonStateClear = currentButtonStateClear;     // resets the clear button state to LOW
//attempt at making the menu stay when option is selected
   /* if (menuSelected) {
    tft.fillScreen(ILI9341_BLACK);
    tft.setCursor(10, 10);
    tft.println("Option Selected");
    delay(2000);
  }*/
}
/*need to create a boolean function for the debounce time, as the delays in the main loop are 
messing up the timer
//logs data into SDCardFile, eg. logSensorData("Humidity", bme.humidity)
void logSensorData(const String& dataType, float value){
myFile = SD.open("data.txt", FILE_WRITE);
  if (myFile) {
    dataFile.print(dataType);
    dataFile.print(": ");
    dataFile.println(value);
    dataFile.close();
    Serial.println("Sensor data logged to SD card");
  } else {
    Serial.println("Error opening datalog.txt");
  }
}*/