// Code licensed under GPL-v3

// Simplified mockup of an Arduino Nano-based light control system
// All Digital pins and one Analog pin on the Arduino Nano used
// D0 - D2 and D4 - D7 are for LCD 
// D3 is for the PHR (digital)
// D8 - D13 are for buttons TODO - Change D13 to LED control
// A0 is for the PHR (analog)

// Pinout for the Arduino Micro is as follows:
// D11, D12, D7 - D10 are for LCD (reverse order)
// LiquidCrystal lcd(11, 12, 10, 9, 8, 7);
// D13 is for LED Control
// D18 - D23 are for buttons
// A6 is PHR (analog)
// D5 is PHR (digital)

#include <LiquidCrystal.h>

LiquidCrystal lcd(0, 1, 4, 5, 6, 7);
//E     - 1
//RS    - 0
//BKLT  - 2
//D1-D4 - 4-7
const int bkltPin = 2;

const uint8_t buttonPins[] = {8, 9, 10, 11, 12, 13};
// B_1 - Left  [a]
const int buttonLeft = buttonPins[0];
// B_2 - Up    [w]
const int buttonUp = buttonPins[1];
// B_3 - Right [d]
const int buttonRight = buttonPins[2];
// B_4 - Down  [s]
const int buttonDown = buttonPins[3];  
// B_5 - Enter [e]
const int buttonEnter = buttonPins[4];
// B_6 - Back  [q]
const int buttonBack = buttonPins[5];

// const int phrPinD = 3;
// May need to be moved to A0 (pin 19)
const int phrPinA = A0;
// editable PHR limit
int phrLimit = 500;

const int ledOutPin = 3;

bool backlight = true;

int button;

uint8_t down[8] = {
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b00111,
  0b00010,
  0b00000,
};
uint8_t up[8] = {
  0b00000,
  0b00010,
  0b00111,
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b00000,
};
uint8_t right[8] = {
  0b00000,
  0b00000,
  0b00010,
  0b00011,
  0b00010,
  0b00000,
  0b00000,
  0b00000,
};
uint8_t left[8] = {
  0b00000,
  0b00000,
  0b01000,
  0b11000,
  0b01000,
  0b00000,
  0b00000,
  0b00000,
};

uint8_t ohm[8] = {
  //Found out this character is 244 or 154 depending on model
  0b00000,
  0b01110,
  0b10001,
  0b10001,
  0b01010,
  0b11011,
  0b00000,
  0b00000,
};

void wait(){
  delay(800);
}
void pause(){
  delay(150);
}

void bottom_clear(){
  lcd.setCursor(0, 1);
  lcd.print("                 ");
  lcd.setCursor(0, 1);
}

int bkltctl(int state){
  switch (state){
    case 0:
      digitalWrite(bkltPin, LOW);
      break;
    case 1:
      digitalWrite(bkltPin, HIGH);
      break;
  }
}

int lightctl(int state){
  switch (state){
    case 0:
      digitalWrite(ledOutPin, LOW);
      break;
    case 1:
      digitalWrite(ledOutPin, HIGH);
      break;
  }
}

void setup() {
  // put your setup code here, to run once:
  lcd.begin(16, 2);
  lcd.print("Setting up ");

  lcd.setCursor(0,1);
  lcd.print("Custom Chars");
  lcd.createChar(2, up);
  lcd.createChar(3, down);
  lcd.createChar(4, right);
  lcd.createChar(5, left);
  lcd.createChar(6, ohm);
  pinMode(bkltPin, OUTPUT);
  if (backlight){
    bkltctl(1);
  }
  wait();
  bottom_clear();
  lcd.setCursor(0,1);
  lcd.print("Buttons");
  for (uint8_t i = 0; i < sizeof(buttonPins); i++){
    pinMode(buttonPins[i], INPUT_PULLUP);
  }
  wait();
  bottom_clear();
  lcd.print("PHR");
  //pinMode(phrPinD, INPUT_PULLUP);
  wait();
  bottom_clear();
  
  lcd.print("LEDs");
  pinMode(ledOutPin, OUTPUT);
  lightctl(1);
  wait();
  lightctl(0);
  lcd.clear();
  lcd.print("Done!");
  lcd.setCursor(0,1);
  lcd.print("Press Enter \x06");
}

void main_menu(){
  String menu[] = {"Current Reading","Passive Mode", "Settings", "--------------"};
  int max_op = sizeof(menu)-1;
  String arrow; //up or down arrow based on location
  
  int op_one = 0;
  int op_two = 1;

  int selection = 0;
  bool selected = false;
  while (!selected){
    lcd.setCursor(0,0);
    lcd.print("\x04" + menu[op_one]);
    lcd.setCursor(0,1);
    lcd.print(" " + menu[op_two]);
    if (op_two == 1){
      lcd.setCursor(15,1);
      //down arrow
      arrow = "\x03";
    }
    else if (op_two == 2) {
      lcd.setCursor(15,0);
      //up arrow
      arrow = "\x02";
    }
    lcd.print(arrow);
    // Process Up Button
    if (digitalRead(buttonUp) == LOW){
      pause();
      // Cap minimum selection to 0
      if (selection > 0 && op_one > 0){
        selection--;
      }
      if ( op_one > 0 ){
        op_one--;
        op_two--;
      }
      lcd.clear();
    }
    // Process Down Button
    if (digitalRead(buttonDown) == LOW){
      pause();
      // Cap maximum selection to maximum
      if (selection == max_op){
        selection = 0;
        op_one = 0;
        op_two = 1;
      }
      else if (selection < max_op && op_two < max_op){
        selection++;
      }
      if ( op_two < max_op ){
        op_one++;
        op_two++;
      }
      lcd.clear();
    }
    
    if (digitalRead(buttonEnter) == LOW){
        switch (selection){
          case 0:
            live_reading();
            break;

          case 1:
            selected = true;
            passive();
            break;

          case 2:
            pause();
            settings_menu();
            break;
        }
    }
  }
}

void live_reading(){
  bool back = false;
  while (!back){
    lcd.clear();
    lcd.setCursor(0,0);
    lcd.print("PHR Reading");
    lcd.setCursor(4,1);
    lcd.print(/*String(digitalRead(phrPinD)) + "|" + */String(analogRead(phrPinA)));
    lightmon();
    pause();

    if (digitalRead(buttonBack) == LOW || digitalRead(buttonEnter) == LOW){
      back == true;
      break;
    }
  }
}

void passive(){
  bkltctl(0);
  lcd.clear();
  bool back = false;
  do {
    lightmon();
    if (digitalRead(buttonBack) == LOW){
      bkltctl(1);
      back = true;
      main_menu();
    }
  } while (!back);
}

void settings_menu(){
  lcd.clear();
  String menu[] = {"Backlight", "PHR Range", "--------------"};
  int max_op = sizeof(menu)-1;
  String arrow; //up or down arrow based on location
  
  int op_one = 0;
  int op_two = 1;

  int selection = 0;
  bool selected = false;
  while (!selected){
    lcd.setCursor(0,0);
    lcd.print("\x04" + menu[op_one]);
    lcd.setCursor(0,1);
    lcd.print(" " + menu[op_two]);
    if (op_two == 1){
      lcd.setCursor(15,1);
      //down arrow
      arrow = "\x03";
    }
    else if (op_two % 2) {
      lcd.setCursor(15,0);
      //up arrow
      arrow = "\x02";
    }
    lcd.print(arrow);
    // Process Up Button
    if (digitalRead(buttonUp) == LOW){
      pause();
      // Cap minimum selection to 0
      if (selection > 0 && op_one > 0){
        selection--;
      }
      if ( op_one > 0 ){
        op_one--;
        op_two--;
      }
      lcd.clear();
    }
    // Process Down Button
    if (digitalRead(buttonDown) == LOW){
      pause();
      // Cap maximum selection to maximum
      if (selection < max_op && op_two < max_op){
        selection++;
      }
      if ( op_two < max_op ){
        op_one++;
        op_two++;
      }
      lcd.clear();
    }
    if (digitalRead(buttonBack) == LOW){
      pause();
      main_menu();
      break;
    }
    if (digitalRead(buttonEnter) == LOW){
      pause();
        switch (selection){
          case 0:
            setting_bklt();
            break;

          case 1:
            phr_range();
            break;
        }
    }
  }
}

void setting_bklt(){
  lcd.clear();
  lcd.setCursor(3,0);
  lcd.print("Backlight");

  bool done = false;
  while (!done){
    bool state = digitalRead(bkltPin);
    lcd.setCursor(0,1);
    if (state == HIGH){
        lcd.print("\x05     On       \x04");
    }
    if (state == LOW){
      lcd.print("\x05     Off      \x04");
    }

    if (digitalRead(buttonLeft) == LOW || digitalRead(buttonRight) == LOW){
      pause();
      digitalWrite(bkltPin, !state);
      bottom_clear();
    }
    
    if (digitalRead(buttonEnter) == LOW || digitalRead(buttonBack) == LOW){
      pause();
      done = true;
      settings_menu();
      break;
    } 
  }
}

void phr_range(){
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("PHR Limit");

  bool done = false;
  do {
    lcd.setCursor(0,1);
    lcd.print("\x05     "+ String(phrLimit) +"\x06    \x04");
    if (digitalRead(buttonLeft) == LOW){
      pause();
      if (phrLimit > 250){
        phrLimit -= 250;
      }
      bottom_clear();
    }
    if (digitalRead(buttonRight) == LOW){
      pause();
      if (phrLimit < 1500){
        phrLimit += 250;
      }
      bottom_clear();
    }
    if (digitalRead(buttonEnter) == LOW || digitalRead(buttonBack) == LOW){
      pause();
      done = true;
      settings_menu();
      break;
    }
    lightmon();
  } while (!done);
}

void lightmon(){
   if (analogRead(phrPinA) > phrLimit){
    digitalWrite(ledOutPin, HIGH);
  }
  if (analogRead(phrPinA) <= phrLimit){
    digitalWrite(ledOutPin, LOW);
  }
}

void loop() {
  // put your main code here, to run repeatedly:
  lightmon();
  if(digitalRead(buttonEnter) == LOW){
    pause();
    lcd.clear();
    main_menu();
  }
}