KVFileReader.h

#ifndef __KVFILEREADER_H
#define __KVFILEREADER_H
 
#include <string>
#include <fstream>
#include "KVBase.h"
#include "TSystem.h"
#include "KVString.h"
#include "TString.h"
 
class KVFileReader : public KVBase {
private:
   void init()
   {
      reading_line = "";
      nline = 0;
      skip_comments = !comment_string.IsNull();
   }
   void StoreParameters(const KVString& pattern)
   {
      items.clear();
      reading_line.Begin(pattern);
      while (!reading_line.End()) items.emplace_back(reading_line.Next(kTRUE).Data());
   }
 
   void AddParameters(const KVString& pattern)
   {
      reading_line.Begin(pattern);
      while (!reading_line.End()) items.emplace_back(reading_line.Next(kTRUE).Data());
   }
 
 
protected:
    std::vector<std::string> items;
   KVString reading_line, file_name, comment_string;
   Int_t nline;
   Bool_t status;
   Bool_t skip_comments = false;
 
public:
   std::ifstream f_in;
 
   enum class ReadStatus {
      EmptyLine, 
      OK,        
      ParamMismatch,
      CommentLine,
      EndOfFile 
   };
 
   KVString GetReadStatus(ReadStatus s)
   {
      switch (s) {
         case ReadStatus::EmptyLine:
            return "EmptyLine";
         case ReadStatus::CommentLine:
            return "CommentLine";
         case ReadStatus::EndOfFile:
            return "EndOfFile";
         case ReadStatus::OK:
            return "OK";
         case ReadStatus::ParamMismatch:
            return "ParamMismatch";
      }
      return "???";
   }
   KVFileReader(const KVString& comments = "")
      : comment_string(comments)
   {
      init();
   }
 
   KVString GetFileName()
   {
      return file_name;
   }
 
   void Clear(Option_t* /*opt*/ = "") override
   {
      init();
   }
 
   Bool_t PreparForReadingAgain()
   {
      CloseFile();
      Clear();
      return OpenFileToRead(GetFileName());
   }
 
   Bool_t OpenFileToRead(const KVString& filename)
   {
 
      TString _filename = filename;
      gSystem->ExpandPathName(_filename);
      file_name = _filename;
 
      f_in.open(_filename.Data());
      status = f_in.good();
 
      if (!status)
         Error("OpenFileToRead", "Failed to open file %s", _filename.Data());
 
      return status;
   }
 
   Bool_t IsOK()
   {
      return f_in.good();
   }
 
   void CloseFile()
   {
      if (f_in.is_open()) f_in.close();
   }
 
   ReadStatus ReadLine(const KVString& pattern = "")
   {
      reading_line.ReadLine(f_in);
      if (!IsOK()) return ReadStatus::EndOfFile;
 
      nline++;
      if (skip_comments && reading_line.BeginsWith(comment_string)) return ReadStatus::CommentLine;
      if (!pattern.IsNull())
         StoreParameters(pattern);
 
      return ReadStatus::OK;
   }
 
   ReadStatus ReadLineAndAdd(const KVString& pattern = "")
   {
      reading_line.ReadLine(f_in);
      if (!IsOK()) return ReadStatus::EndOfFile;
 
      nline++;
      if (skip_comments && reading_line.BeginsWith(comment_string)) return ReadStatus::CommentLine;
      if (!pattern.IsNull())
         AddParameters(pattern);
 
      return ReadStatus::OK;
   }
 
   ReadStatus ReadLineAndCheck(Int_t nexpect, const KVString& pattern)
   {
      reading_line.ReadLine(f_in);
      if (!IsOK()) return ReadStatus::EndOfFile;
 
      nline++;
      if (skip_comments && reading_line.BeginsWith(comment_string)) return ReadStatus::CommentLine;
 
      GetCurrentLine().RemoveAllExtraWhiteSpace();
 
      if (GetCurrentLine().IsNull()) {
         return ReadStatus::EmptyLine;
      }
      StoreParameters(pattern);
      if (GetNparRead() != nexpect) {
         return ReadStatus::ParamMismatch;
      }
      return ReadStatus::OK;
   }
   ReadStatus ReuseLineAndCheck(Int_t nexpect, const KVString& pattern)
   {
 
      StoreParameters(pattern);
      if (GetNparRead() != nexpect) {
         return ReadStatus::ParamMismatch;
      }
      return ReadStatus::OK;
   }
 
   KVString GetCurrentLine()
   {
      return reading_line;
   }
 
   Int_t GetNparRead() const
   {
      return items.size();
   }
   Int_t GetNlineRead() const
   {
      return nline;
   }
 
   Double_t GetDoubleReadPar(Int_t pos) const
   {
      return GetReadPar(pos).Atof();
   }
   Int_t GetIntReadPar(Int_t pos) const
   {
      return GetReadPar(pos).Atoi();
   }
   KVString GetReadPar(Int_t pos) const
   {
      return items[pos].c_str();
   }
 
   ClassDefOverride(KVFileReader, 2) //Manage the reading of file
};
 
#endif