parser.h

#ifndef SSVJOY_PARSER_H
#define SSVJOY_PARSER_H

#include <memory>

#include "option.h"
#include "structure.h"

void (*callback)(Type type, byte id, Data data, byte checksum, bool chk);
void (*error)();

char buffer[256] = {0, };
int buffer_idx = 0;
bool read_data = false;

bool compute_checksum(char* data, int size) { 
  byte check = 0;
  for (int i = 0; i < size; i++) { 
    check ^= data[i];
  }
  if (check == 0) {
    return true;
  }
  else {
    return false;
  }
}

// STX : $
// ETX : #
//X $(TYPE)(FLOAT DATA)(CHK 1byte)#
//X CHECKSUM 1 BYTE : 
//  ALL ^ Compute 
void read_next(int value) { 
  if (buffer_idx > 200) { 
    error();
    memset(buffer, 0, sizeof(buffer));
    buffer_idx = 0;
  }
  else if (value == '$') { 
      read_data = true;
  }
  else if (value == '#') { 
    read_data = false;
    ParseResult pr = *(ParseResult*)&buffer[0];

    bool chk = compute_checksum(buffer, buffer_idx);
    if (chk == false && !DEBUG_FLAG) { 
      Serial.print("Checksum Error !!!\n");
    }else { 
      callback(pr.type, pr.id, pr.data, pr.checksum, chk);
    }

    memset(buffer, 0, sizeof(buffer));
    buffer_idx = 0;
  }
  else if (read_data) { 
    buffer[buffer_idx] = value;
    buffer_idx += 1;
  }
}

#endif