/*
  Forum: https://forum.arduino.cc/t/esp32-serial-kommunikation-mit-arduino-uno-grbl/1239346
  Wokwi: https://wokwi.com/projects/393623376239161345

  ec2021

*/

struct tokenStruct {
    char name[8];
    byte num;
};

const tokenStruct tokens[] = {
  {"M2",0},
  {"M7",0},
  {"M8",0},
  {"G0",2},
  {"G1",2},
  {"G21",0},
  {"G90",0},
  {"F1000",0},
};
const int noOfTokens = sizeof(tokens)/sizeof(tokens[0]);

void setup(){
  Serial.begin(115200);
  check("M1");
  check("M2");
  check("M21");
  check("G0");
  check("G012345");
  check("F1000");
}

void loop(){
}

void check(char * line){
  Serial.print(line);
  if (isValid(line)) {
      Serial.println(" is valid");
  } else {
      Serial.println(" is not valid");
  }
}

boolean isValid(char * token){
  for (int i = 0; i<noOfTokens;i++){
    if (tokens[i].num == 0){
      if (strcmp(token,tokens[i].name) == 0) {
        return true;
      }
    } else {
      if (strncmp(token,tokens[i].name, tokens[i].num) == 0) {
        return true;
      }
    }
  }
  return false;
}