//
// hello.D11C.echo.ino
//
// D11C USB echo hello-world
//
// Neil Gershenfeld 11/29/19
// Modified by Seung Hyeon 10/7/22 with the help of Anthony (HTMAA 2022 Instructor)
//
// This work may be reproduced, modified, distributed,
// performed, and displayed for any purpose, but must
// acknowledge this project. Copyright is retained and
// must be preserved. The work is provided as is; no
// warranty is provided, and users accept all liability.
//

#define LED1 4
#define LED2 8
#define button 2

void setup() {
   SerialUSB.begin(0);
   //making LED outputs

   pinMode(LED1, OUTPUT);
   pinMode(LED2, OUTPUT);
   pinMode(button, INPUT_PULLUP); //pull up resistor-10k
   }

#define max_buffer 25 //making a variable
int count = 0;
int current_state = 1;
int previous_state = 1;

void loop() {
  //Seung Hyeon's code for LED on/off switch
  if (digitalRead(button)==LOW && count==0 && previous_state==1){ //when you press the button and make the voltage grounded, it's equal to LOW
    digitalWrite(LED1,HIGH);
    digitalWrite(LED2,HIGH);
    count = 1;
    previous_state = 0;
    current_state = 0; //of the buttons
  }  
  //delay(2000); //giving delay time for the button press (but poor timing)
  if (digitalRead(button)==LOW && count==1 && previous_state==1){
    digitalWrite(LED1,LOW);
    digitalWrite(LED2,LOW);
    count = 0;
    previous_state = 0;
    current_state = 0;
  
  }
  //delay(2000); //giving delay time for the button press
  if (digitalRead(button)==HIGH){
    previous_state = current_state;
    current_state = 1;
  }

 //  Serial.println(count);
  // Neil's code for echo
   static char chr;
   static char buffer[max_buffer] = {0}; //array of zeros
   static int index; 
   if (SerialUSB.available()) {
      chr = SerialUSB.read();
      SerialUSB.print("hello.D11C.echo: you typed \"");
      buffer[index++] = chr;
      if (index == (max_buffer-1))
         index = 0;
      SerialUSB.print(buffer);
      SerialUSB.println("\"");
      }
   }