//: C02:Breakup.cpp
// From Thinking in C++, 2nd Edition
// Available at http://www.BruceEckel.com
// (c) Bruce Eckel 2000
// Copyright notice in Copyright.txt
// Breaks a file up into smaller files for 
// easier downloads
#include "../require.h"
#include <iostream>
#include <fstream>
#include <iomanip>
#include <strstream>
#include <string>
using namespace std;

int main(int argc, char* argv[]) {
  requireArgs(argc, 1);
  ifstream in(argv[1], ios::binary);
  assure(in, argv[1]);
  in.seekg(0, ios::end); // End of file
  long fileSize = in.tellg(); // Size of file
  cout << "file size = " << fileSize << endl;
  in.seekg(0, ios::beg); // Start of file
  char* fbuf = new char[fileSize];
  require(fbuf != 0);
  in.read(fbuf, fileSize);
  in.close();
  string infile(argv[1]);
  int dot = infile.find('.');
  while(dot != string::npos) {
    infile.replace(dot, 1, "-");
    dot = infile.find('.');
  }
  string batchName(
    "DOSAssemble" + infile + ".bat");
  ofstream batchFile(batchName.c_str());
  batchFile << "copy /b ";
  int filecount = 0;
  const int sbufsz = 128;
  char sbuf[sbufsz];
  const long pieceSize = 1000L * 100L;
  long byteCounter = 0;
  while(byteCounter < fileSize) {
    ostrstream name(sbuf, sbufsz);
    name << argv[1] << "-part" << setfill('0') 
      << setw(2) << filecount++ << ends;
    cout << "creating " << sbuf << endl;
    if(filecount > 1) 
      batchFile << "+";
    batchFile << sbuf;
    ofstream out(sbuf, ios::out | ios::binary);
    assure(out, sbuf);
    long byteq;
    if(byteCounter + pieceSize < fileSize)
      byteq = pieceSize;
    else
      byteq = fileSize - byteCounter;
    out.write(fbuf + byteCounter, byteq);
    cout << "wrote " << byteq << " bytes, ";
    byteCounter += byteq;
    out.close();
    cout << "ByteCounter = " << byteCounter 
      << ", fileSize = " << fileSize << endl;
  }
  batchFile << " " << argv[1] << endl;
} ///:~