#ifndef __TwoDLookup_h_
#define __TwoDLookup_h_

#include <string>
#include <set>
#include <vector>
#include <map>
#include <iostream>

// This class maps a pair of strings to a string.  If the pair of input strings
// cannot be found, then we return the empty string.
//
// This can easily be read from or saved to a CSV file.  The top row of the
// file has the column headers.  The left column of the file has the row
// headers.  The top left cell is ignored on reading, and blank after writing.
// The remainder of the table contains the values which are referenced by the
// row and column headers.

class TwoDArray
{
public:
  typedef std::vector< std::string > StringList;
private:
  std::set< std::string > _allCols, _allRows;
  StringList _colsInOrder, _rowsInOrder;
  typedef std::pair< std::string, std::string > Key;
  std::map< Key, std::string > _values;
public:
  TwoDArray();
  void appendFromCSV(std::string const &fileName);
  void loadFromCSV(std::string const &fileName) 
  { clear(); appendFromCSV(fileName); }
  void writeToCSV(std::string const &fileName, bool writeHeader = true) const;
  void writeToCSV(std::ostream &stream, bool writeHeader = true) const;
  std::string writeToCSV(bool writeHeader = true) const;
  void writeToCSV(char const *fileName, bool writeHeader = true) const
  { writeToCSV((std::string)fileName, writeHeader); }
  std::string get(std::string const &colHeader, 
		  std::string const &rowHeader) const;
  void add(std::string const &colHeader, std::string const &rowHeader, 
	   std::string const &value);
  void clear();
  bool containsRow(std::string rowHeader) const;

  // Keep the column headers, nothing else.
  void eraseAllRows();

  StringList const &getRowHeaders() const { return _rowsInOrder; }
  StringList const &getColHeaders() const { return _colsInOrder; }
};

#endif