//****************************************************************************
// Filename: Csv.h
// Copyright 1999 Daniel X. Pape. All rights reserved.
//
// Description: A parser for a string of comma separated values.
//
// This is based on a similar class described in "The Practice of
// Programming" by Brian W. Kernighan and Rob Pike.
//
// Sample input: "foo",1,1.485,"la la lala","poit"
//
//****************************************************************************
// Revision History:
// Sunday, July 11, 1999 - Original
//****************************************************************************

#include "Csv.h"

using std::string;


// ***************************************************************************
// Function: Constructor
//     Desc: 
// ***************************************************************************
Csv::Csv(string line, string sep)
    : nField_(0), line_(line), fieldSep_(sep)
{
    split();
}


// ***************************************************************************
// Function: split
//     Desc: Split line into fields
// ***************************************************************************
int Csv::split(void)
{
    string field;
    size_type i, j;

    nField_ = 0;
    if(line_.length() == 0)
        return 0;
    i = 0;

    do {

        if(i < line_.length() && line_[i] == '"')
            j = advQuoted(line_, field, ++i); // skip quote
        else
            j = advPlain(line_, field, i);
        
        if(nField_ >= fields_.size())
            fields_.push_back(field);
        else
            fields_[nField_] = field;
        nField_++;
        
        i = j+1;

    } while(j < line_.length());
    
    return nField_;

}


// ***************************************************************************
// Function: advQuoted
//     Desc: quoted field, return index of next separator
// ***************************************************************************
int Csv::advQuoted(const string& s, string& field, size_type i)
{
    size_type j;

    field = "";
    for(j=i; j<s.length(); j++)
    {
        if(s[j] == '"' && s[++j] != '"')
        {
            size_type k = s.find_first_of(fieldSep_, j);
            if(k > s.length()) // no sep found
                k = s.length();
            for(k -= j; k-- > 0; )
                field += s[j++];
            break;
        }
        field += s[j];
    }
    return j;
}


// ***************************************************************************
// Function: advPlain
//     Desc: unquoted field, return index of next separator
// ***************************************************************************
int Csv::advPlain(const string& s, string& field, size_type i)
{
    size_type j = s.find_first_of(fieldSep_, i);

    if(j > s.length()) // no sep found
        j = s.length();

    field = string(s, i, j-i);

    return j;
}


// ***************************************************************************
// Function: GetField
//     Desc: return n-th field
// ***************************************************************************
string Csv::GetField(size_type n)
{
    if(n > nField_)
        return "";
    else
        return fields_[n];
}