BaseConverter

// BaseConverter.h: interface for the CBaseConverter class.
//
//////////////////////////////////////////////////////////////////////

#if !defined(AFX_BASECONVERTER_H__28149E41_2127_11D7_A179_000103DD18CD__INCLUDED_)
#define AFX_BASECONVERTER_H__28149E41_2127_11D7_A179_000103DD18CD__INCLUDED_

#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000
# include <string>
# include <cassert>
# include <algorithm>
# include <cmath>
using std::string;

namespace NO5
{
    namespace Math
    {
        class CBaseConverter
        {
            // returns -1 if its not a valid character
            static int GetDecValue(char c)
            {
                int res = -1;

                if( c >= '0' && c <= '9'){
                    res = (int(c) - int('0'));
                }
                else if(c >= 'A' && c <= 'Z'){
                    res = (int(c) - int('A'));
                    res += 10;
                }
                else if(c >= 'a' && c <= 'z'){
                    res = (int(c) - int('a'));
                    res += 10;
                }
                return res;
            }
            static char GetBaseXDigit(unsigned int i,bool UpCase =\
                true)
            {
                char res;

                if(i >= 0 && i <= 9){
                    res = char(int('0') + i);
                }
                else if(i < 36){
                    if(UpCase){
                        res = char(int('A') + i - 10);
                    }
                    else{
                        res = char(int('a') + i - 10);
                    }
                }
                else{
                    assert(0);
                    // throw something;
                }
                return res;
            }
            static bool IsBaseXDigit(char c,unsigned int b)
            {
                int dec = GetDecValue(c);

                return (dec > 0 && dec < b);
            }

        public:
            // returns -1 if value is not valid
            static int FromBaseX(const string &value,unsigned\
                int b)
            {
                int res = 0;
                const string::size_type len = value.length();
                string::size_type i;
                int tmp;

                for(i=0;i<len;i++){
                    tmp = GetDecValue(value[len - i - 1]);
                    if(tmp < 0){
                        res = -1;
                        break;
                    }
                    res += tmp * ( pow(b,i));
                }
                return res;
            }
            static string ToBaseX(unsigned int value,unsigned int b,
                bool UpCase = true)
            {
                unsigned int q,r;
                string res;

                q = value;
                while(q != 0){
                    r = q % b;
                    q = q / b;
                    res += GetBaseXDigit(r,UpCase);
                }
                std::reverse(res.begin(),res.end());
                return res;
            }
            static string BaseXtoY(const string &value,unsigned int\
                b_x,unsigned int b_y,bool bUpCase = true)
            {
                string res;

                if(b_x == b_y)
                    res = value;
                else
                    res = ToBaseX(FromBaseX(value,b_x),b_y,bUpCase);
                return res;
            }
        };
    }
}

#endif // !defined(AFX_BASECONVERTER_H__28149E41_2127_11D7_A179_000103DD18CD__INCLUDED_)