//
// Created by Kosho on 2020年8月14日.
//

#ifndef PYTHONVM_BUFFEREDINPUTSTREAM_HPP
#define PYTHONVM_BUFFEREDINPUTSTREAM_HPP

#include<stdio.h>

#define BUFFER_LEN 256

class BufferedInputStream {
private:
 FILE *fp;
 const char *file_path;
 char szBuffer[BUFFER_LEN];
 unsigned short index;

public:
 BufferedInputStream(char const *file_path) {
 fp = fopen(file_path, "rb");
 this->file_path = file_path;
 fread(szBuffer, BUFFER_LEN * sizeof(char), 1, fp);
 index = 0;
 }

 ~BufferedInputStream() {
 close();
 }

 const char *get_file_path() {
 return file_path;
 }

 char read() {
 if (index < BUFFER_LEN)
 return szBuffer[index++];
 else {
 index = 0;
 fread(szBuffer, BUFFER_LEN * sizeof(char), 1, fp);
 return szBuffer[index++];
 }
 }

 int read_int() {
 int b1 = read() & 0xff;
 int b2 = read() & 0xff;
 int b3 = read() & 0xff;
 int b4 = read() & 0xff;

 return b4 << 24 | b3 << 16 | b2 << 8 | b1;
 }

 double read_double() {
 char t[8];
 for (int i = 0; i < 8; i++) {
 t[i] = read();
 }

 return *(double *) t;
 }

 void unread() {
 index--;
 }

 void close() {
 if (fp != NULL) {
 fclose(fp);
 fp = NULL;
 }
 }
};


#endif //PYTHONVM_BUFFEREDINPUTSTREAM_HPP