#include "DigiKeyboard.h"
#include <stdio.h>

#define KEYPAD_1                (  89  | 0xF000 )
#define KEYPAD_2                (  90  | 0xF000 )
#define KEYPAD_3                (  91  | 0xF000 )
#define KEYPAD_4                (  92  | 0xF000 )
#define KEYPAD_5                (  93  | 0xF000 )
#define KEYPAD_6                (  94  | 0xF000 )
#define KEYPAD_7                (  95  | 0xF000 )
#define KEYPAD_8                (  96  | 0xF000 )
#define KEYPAD_9                (  97  | 0xF000 )
#define KEYPAD_0                (  98  | 0xF000 )

int keypad[10] = {KEYPAD_0, KEYPAD_1, KEYPAD_2, KEYPAD_3, KEYPAD_4, KEYPAD_5, KEYPAD_6, KEYPAD_7, KEYPAD_8, KEYPAD_9};

void typeAltChar(char c){
  digitalWrite(1, HIGH);   
  char alt_code[4];
  snprintf(alt_code, 4, "%d", c); // convert int to decimal
  int i=0;
  while(alt_code[i]!=0){
      if(i > 0 && alt_code[i-1]==alt_code[i]){
        DigiKeyboard.sendKeyPress(0,MOD_ALT_LEFT); // Release all keys except "ALT"
      }
      DigiKeyboard.sendKeyPress(keypad[alt_code[i]-'0'],MOD_ALT_LEFT);
      ++i;
  }
  DigiKeyboard.sendKeyPress(0,0);   
  digitalWrite(1, LOW);
}

void typeAltString(char* string){
  int i=0;
  while(string[i]!=0){
    typeAltChar(string[i]);
    ++i;
  }
}

void setup() {
  pinMode(1, OUTPUT); // setup LED

  // setup keyboard
  DigiKeyboard.sendKeyStroke(0);
  
  DigiKeyboard.sendKeyStroke(KEY_R, MOD_GUI_LEFT); // WIN+R open run box
  DigiKeyboard.delay(300);
  // using ALT keys to be keyboard layout agnostic https://en.wikipedia.org/wiki/Alt_code
  typeAltString("echo test");
  DigiKeyboard.sendKeyStroke(KEY_ENTER);
}

void loop() {
}