/*
 ************************************************************** 
 *               Coal Stoker Flame Size Detector              * 
 *              Inspired by Uri Shaked project at             *
 *   https://wokwi.com/arduino/projects/305193627138654786    *
 *                Layout used as starting point               *
 *                  Copyright 2022 John Clark                 *
 *                       Version 0.10                         *
 **************************************************************
*/
/*
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);  //define I2C address 0x27, 16 column and 2 rows
*/
//#include <SPI.h>
#include <Wire.h>
#include "Adafruit_GFX.h"
#include "Adafruit_SSD1306.h"

#define SCREEN_WIDTH        128 // OLED display width, in pixels
#define SCREEN_HEIGHT        64 // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
#define OLED_RESET            -1 // Reset pin # (or -1 if sharing Arduino reset pin)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);


int flamelevel = 0; // mapped and inverted % of sensor range
#define greenLED 7 // fire okay or firing
#define redLED 2 // warning or flashing alert

// empirically relate flame % to actual fire condition (TBD)
const int minSurvive = 15; // minimum level for idle, below is outfire
const int idleLow = 20; // lowest reading for healthy idle
const int idleTarget = 30; // target reading for resting idle
const int firingLow = 70; // lowest reading for actively firing
const int firingHigh = 90; // reading for full firing

String stringOne, stringTwo, stringThree;
int analogValue;

void setup() {
  delay(10);
  /*lcd.init();
  lcd.clear();
  lcd.backlight();
  */

  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }

  display.setTextSize(2);
  display.setTextColor(SSD1306_WHITE);
  display.clearDisplay();
  display.display();
  
  Serial.begin(9600);
  display.clearDisplay();
    display.setCursor(5,10);
    display.println(" Flame Sensor");
    printOled();

  pinMode(greenLED, OUTPUT); // set green pin led as output
  digitalWrite(greenLED, LOW); // turn off green led

  pinMode(redLED, OUTPUT); // set red led pin as output
  digitalWrite(redLED, LOW); // turn off red led
}

void loop() {
  analogValue = analogRead(A0);
  Serial.print("Sensor RAW: ");
  Serial.println(analogValue);
  flamelevel = map(analogValue, 0, 1024, 100, 0);
  Serial.print(flamelevel);
  Serial.println("%");

  // disabling the lcd commands makes serial print work
  /*lcd.setCursor(0, 0);
  lcd.print(F("Flame: "));
  */

  /*display.clearDisplay();
  drawText(5, 10, 2, "Thanks For The Help!");
  display.display();
  */

  if (flamelevel >= firingHigh) { // stoker is fully firing
    // lcd.print("Full Fire");
    display.clearDisplay();
    display.setCursor(5,10);
    display.println(" Full Fire");
    printOled();
    /*display.print("    ");
    display.print(flamelevel);
    display.println("%");
    display.print("  Raw:");
    display.print(analogValue);
    display.display();
    */

    /*stringOne = "Full Fire     ";
    stringOne = stringOne + flamelevel;
    stringTwo = stringOne + "%     Raw:";
    stringThree = stringTwo + analogValue;
    Serial.println(stringOne);
    
    drawText(5, 10, 2, stringThree);
    display.setCursor(5,10);
    */

    digitalWrite(greenLED, HIGH); // turn on green led
    digitalWrite(redLED, LOW); // turn off red led
    delay(300);
    digitalWrite(greenLED, LOW); // turn off green led for flash
  }

  if ((flamelevel >= firingLow) && (flamelevel < firingHigh)) { // stoker is firing
    //lcd.print("Firing   ");
    display.clearDisplay();
    display.setCursor(5,10);
    display.println("  Firing");
    printOled();
    /*
    display.print("    ");
    display.print(flamelevel);
    display.println("%");
    display.print("  Raw:");
    display.print(analogValue);
    display.display();
    */

    /*display.clearDisplay();
    stringOne = "  Firing      ";
    stringOne = stringOne + flamelevel;
    stringTwo = stringOne + "%     Raw:";
    stringThree = stringTwo + analogValue;
    Serial.println(stringOne);
    
    drawText(5, 10, 2, stringThree);
    display.display();
    */

    digitalWrite(greenLED, HIGH); // turn on green led
    digitalWrite(redLED, LOW); // turn off red led
  }

  if ((flamelevel < firingLow) && (flamelevel > idleLow) ) {  // idle fire
    //lcd.print("Idle fire ");
    display.clearDisplay();
    display.setCursor(5,10);
    display.println(" Idle Fire");
    printOled();
    
    /*
    display.clearDisplay();
    stringOne = "Idle Fire     ";
    stringOne = stringOne + flamelevel;
    stringTwo = stringOne + "%     Raw:";
    stringThree = stringTwo + analogValue;
    Serial.println(stringOne);
    
    drawText(5, 10, 2, stringThree);
    display.display();
    */

    digitalWrite(greenLED, HIGH); // turn on green led
    digitalWrite(redLED, HIGH); // turn off red led
  }

  if ((flamelevel <= idleLow) && (flamelevel >= minSurvive) ) {  // low fire
    //lcd.print("Low fire  ");
    display.clearDisplay();
    display.setCursor(5,10);
    display.println(" Low Fire");
    printOled();

    /*
    display.clearDisplay();
    stringOne = " Low Fire     ";
    stringOne = stringOne + flamelevel;
    stringTwo = stringOne + "%     Raw:";
    stringThree = stringTwo + analogValue;
    Serial.println(stringOne);
    
    drawText(5, 10, 2, stringThree);
    display.display();
    */

    digitalWrite(greenLED, LOW); // turn on green led
    digitalWrite(redLED, HIGH); // turn off red led
    // trigger stoker run timer = 2 mins?
  }

  if (flamelevel < minSurvive) {  // fire out
    //lcd.print("FIRE OUT! ");
    display.clearDisplay();
    display.setCursor(5,10);
    display.println("FIRE OUT!!");
    printOled();

    /*
    display.clearDisplay();
    stringOne = "FIRE OUT!!     ";
    stringOne = stringOne + flamelevel;
    stringTwo = stringOne + "%     Raw:";
    stringThree = stringTwo + analogValue;
    Serial.println(stringOne);
    
    drawText(5, 10, 2, stringThree);
    display.display();
    */

    digitalWrite(greenLED, LOW); // turn on green led
    digitalWrite(redLED, HIGH); // turn off red redLED
    delay(300);
    digitalWrite(redLED, LOW); // turn off red led for flash
    // send alert
  }

  /*lcd.setCursor(0, 1);
  lcd.print("   Level: ");
  lcd.print(flamelevel, 0);
  lcd.print("%    ");
  */

  delay(200);
}

/*void drawText(int x, int y, int size, String text) {
  display.setCursor(x, y);
  display.setTextColor(2);
  display.setTextSize(size);
  display.print(text);
}
*/

void printOled() {
  display.print("    ");
  display.print(flamelevel);
  display.println("%");
  display.print("  Raw:");
  display.print(analogValue);
  display.display();
}