/**
   Mini piano for Arduino.

   You can control the colorful buttons with your keyboard:
   After starting the simulation, click anywhere in the diagram to focus it.
   Then press any key between 1 and 8 to play the piano (1 is the lowest note,
   8 is the highest).

   Copyright (C) 2021, Uri Shaked. Released under the MIT License.
*/

#include <Arduino_FreeRTOS.h>
#include "pitches.h"
#include <LiquidCrystal_I2C.h>
#define SPEAKER_PIN A3


const uint8_t buttonPins[] = { 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 };
const int buttonTones[] = {
  NOTE_C4, NOTE_CS4, NOTE_D4, NOTE_DS4, NOTE_E4, NOTE_F4, NOTE_FS4,
  NOTE_G4, NOTE_GS4, NOTE_A4, NOTE_AS4, NOTE_B4, NOTE_C5
};
const int numTones = sizeof(buttonPins) / sizeof(buttonPins[0]);
unsigned long timing;
LiquidCrystal_I2C lcd(0x27, 20, 4);

void LCD_detected();
void LCD_notdetected();
void sound();
TaskHandle_t xHandle;
TaskHandle_t vHandle;
TaskHandle_t zHandle;

void setup() {
  lcd.init();
  xTaskCreate(sound, "sound", 128, NULL, 2, &vHandle);
  xTaskCreate(LCD_detected, "lcd_on", 128, NULL, 3, &xHandle);
  xTaskCreate(LCD_notdetected, "lcd_off", 128, NULL, 1, &zHandle);
  vTaskStartScheduler();
}


void loop() {
}


void LCD_detected(void){
  for(;;){
  lcd.backlight();
  lcd.display();
  lcd.setCursor(1, 0);
  lcd.print("Button:");
  lcd.setCursor(1, 1);
  lcd.print("Tone:");
  vTaskSuspend(xHandle);
  }
}


void LCD_notdetected(void){
  for(;;){
    lcd.noBacklight();
    lcd.noDisplay();
    for (byte i = 0; i < numTones; i++) {
      byte buttonPin = buttonPins[i];
     if (digitalRead(buttonPin) == LOW) {
       vTaskResume( xHandle );
       vTaskResume( vHandle );
     }
    }
  }
}


void sound(void){
  for (uint8_t i = 0; i < numTones; i++) {
    pinMode(buttonPins[i], INPUT_PULLUP);
  }
  pinMode(SPEAKER_PIN, OUTPUT);
  for(;;){
   int pitch = 0;
      for (uint8_t i = 0; i < numTones; i++) {
        if (digitalRead(buttonPins[i]) == LOW) {
          pitch = buttonTones[i];
          lcd.setCursor(9, 0);
          lcd.print(14 - buttonPins[i]);
          lcd.setCursor(9, 1);
          lcd.print(buttonTones[i]);
        }
      }
    if (pitch) {
      tone(SPEAKER_PIN, pitch);
      timing = millis();
    } else {
      noTone(SPEAKER_PIN);
      if (millis() - timing > 2000){
        vTaskSuspend( vHandle );
      }
    }
  }  
}