/// simplified version of hadd to merge two files into a new one
/// necessary since we want to merge our own classes...

void MergeFiles(const Char_t* outFile, const Char_t* file1, const Char_t* file2) {
	//gSystem->Load("StFStatTools");
	TFileMerger* merger = new TFileMerger(kFALSE);
	merger->AddFile(file1);
	merger->AddFile(file2);
	merger->PrintFiles(NULL);
	merger->OutputFile(outFile);
	merger->Merge();

}

void MergeFiles(const Char_t* outFile, const Char_t* files) {
	//gSystem->Load("StFStatTools");
	TFileMerger* merger = new TFileMerger(kFALSE);
	merger->OutputFile(outFile);
	// handle files
	if (!TString(files).MaybeWildcard()) {
		cout << "WARNING - Merging one file only is just copying" << endl;
		merger->AddFile(files);
	} else {
		// wildcard - merge multiple files
		TString basename(files);
		Int_t slashpos = basename.Last('/');
		TString directory;
		if (slashpos >= 0) {
			directory = basename(0, slashpos);
			basename.Remove(0, slashpos + 1);
		} else {
			directory = gSystem->UnixPathName(gSystem->WorkingDirectory());
		}
		const Char_t* file = NULL;
		const Char_t* epath = gSystem->ExpandPathName(directory.Data());
		void *dir = gSystem->OpenDirectory(epath);
		delete[] epath;
		if (dir) {
			TRegexp re(basename, kTRUE);
			while ((file = gSystem->GetDirEntry(dir))) {
				if (!strcmp(file, ".") || !strcmp(file, "..")) {
					continue;
				}
				TString s = file;
				if ((basename != file) && s.Index(re) != kNPOS) {
					TString f = directory;
					f += "/";
					f += file;
					merger->AddFile(f.Data());
					//cout << f.Data() << endl;
				}
			}
		}
	}
	merger->Merge();
}