StringTools.h

/*
 
MIT License
 
Copyright (c) 2017 FMI Open Development / Markus Peura, first.last@fmi.fi
 
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
 
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
 
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
 
*/
/*
Part of Rack development has been done in the BALTRAD projects part-financed
by the European Union (European Regional Development Fund and European
Neighbourhood Partnership Instrument, Baltic Sea Region Programme 2007-2013)
*/
/*
 * StringTools.h
 *
 *  Created on: Jul 21, 2010
 *      Author: mpeura
 */
 
#ifndef DRAIN_STRING_TOOLS
#define DRAIN_STRING_TOOLS
 
#include <limits>
#include <map>
#include <string>
#include <sstream>
 
 
 
namespace drain {
 
 
class StringTools {
 
public:
 
    static
    bool startsWith(const std::string &s, const std::string & substring);
 
 
    static
    bool endsWith(const std::string &s, const std::string & substring);
 
 
 
    static
    std::string & upperCase(std::string & s, size_t n = std::numeric_limits<size_t>::max());
 
 
    static
    char upperCase(char c);
 
 
    static
    std::string & lowerCase(std::string & s, size_t n = std::numeric_limits<size_t>::max());
 
 
    static
    char lowerCase(char c);
 
 
 
 
    static
    void replace(const std::string &src, char search, char repl, std::ostream & ostr);
 
 
    static
    void replace(const std::string &src, char from, char repl, std::string &dst);
 
 
    template <typename S, typename R>
    static
    void replace(const std::string &src, const S & search, const R & repl, std::ostream & ostr){
 
        const size_t length = getLength(search);
        std::string::size_type i = 0;
        std::string::size_type pos;
 
        while (true) {
            pos = src.find(search, i);
            if (pos == std::string::npos){
                ostr << src.substr(i);
                return;
            }
 
            // String was found
            ostr << src.substr(i, pos-i) << repl;
 
            // Jump over <search>: move forward len(search) chars
            i = pos + length;
        }
    }
 
 
 
    template <typename T1, typename T2>
    static inline
    void replace(const std::string &src, const T1 &search, const T2 & repl, std::string & dst){
        std::stringstream result;
        replace(src, search, repl, result);
        dst = result.str();
    }
 
 
 
    /*
    template <typename T1, typename T2>
    static inline
    std::string replace(const std::string &src, const T1 & search, const T2 & repl){
        std::string dst;
        replace(src, search, repl, dst);
        return dst;
    }
    */
 
    // MAP VERSIONS
 
    template <typename T>
    static
    void replace(const std::string & src, const std::map<char,T> & m, std::ostream & ostr){
        typename std::map<char,T>::const_iterator it;
        for (char c: src){
            it = m.find(c);
            if (it == m.end()){
                ostr << c;
            }
            else {
                ostr << it->second;
            }
        }
    };
 
    template <typename T>
    static inline
    void replace(const std::string & src, const std::map<char,T> & m, std::string & dst){
        std::stringstream result;
        replace(src, m, result);
        dst = result.str();
    }
 
 
    static
    void replace(const std::string & src, const std::map<char,char> & m, std::string & dst);
 
    template <class K, class V>
    static inline
    void replace(const std::string & src, const std::map<K,V> & m, std::string & dst){
        replaceWithMap(src, m, dst);
    };
 
    template <class K, class V>
    static inline
    void replace(const std::string & src, const std::initializer_list<std::pair<K,V> > & m, std::string & dst){
        replaceWithMap(src, m, dst);
    };
 
    static
    std::string & convertEscaped(std::string &s);
 
 
private:
 
    static inline
    size_t getLength(char c){
        return 1;
    };
 
    static inline
    size_t getLength(const std::string & s){
        return s.length();
    };
 
    template <class M>
    static inline
    void replaceWithMap(const std::string & src, const M & m, std::string & dst){
 
        if (m.empty()){
            // Replace nothing in src, hence assign it directly to result.
            if (&dst != &src){
                dst = src; // clumsy?
            }
            return;
        }
 
        for (const auto & entry: m){
            // std::cerr << "replacing " << entry.first << " -> " << entry.second << " in " << dst << std::endl;
            replace(dst, entry.first, entry.second, dst);
        }
    };
 
 
public:
 
 
 
    static
    std::string trim(const std::string &s, const std::string &trimChars=" \t\n\r");
 
 
    static
    std::string trimSymmetric(const std::string &s, const std::string &leading= "'\"", const std::string & trailing="");
 
 
 
    static
    bool trimScan(const std::string &s, std::size_t & pos1, std::size_t & pos2, const std::string &trimChars=" \t\n");
 
 
    template <class T, class C>
    static
    void split(const std::string & s, T & sequence, const C &separators, const std::string & trimChars=" \t\n");
    // int
 
    /*
    template <class T>
    static inline
    void split(const std::string & s, T & sequence, char separator=',', const std::string & trimChars=" \t\n"){
        StringTools::split(s, sequence, std::string(1,separator), trimChars);
    }
    */
 
 
    template <class T1, class T2, class C>
    static
    bool split2(const std::string & s, T1 & first, T2 & second, const C &separators, const std::string & trimChars=" \t\n");
 
 
    static
    size_t extractPrefixLength(const std::string & src1, const std::string & src2, size_t step = 1);
 
 
    static
    size_t extractPrefix(const std::string & src1, const std::string & src2,
            std::string & prefix, std::string & dst1, std::string & dst2, size_t step = 1);
 
 
    static inline
    size_t extractPrefix(std::string & s1, std::string & s2, std::string & prefix, size_t step = 1){
        return extractPrefix(s1, s2, prefix, s1, s2, step);
    }
 
 
 
    template <class T>
    static
    std::ostream & join(const T & container, std::ostream & ostr, char separator = 0){
        char sep = 0;
        for (typename T::const_iterator it = container.begin(); it != container.end(); ++it){
            if (sep)
                ostr << sep;
            ostr << *it;
            sep = separator;
        }
        return ostr;
    }
 
 
    template <class T>
    static inline
    std::string join(T & container, char separator = 0){
        std::stringstream sstr;
        StringTools::join(container, sstr, separator);
        return sstr.str();
    }
 
    template <unsigned int S>
    static
    void read(std::istream &istr, std::string & s){
        char buffer[S];
        while (istr.read(buffer, S)){
            s.append(buffer, S);
        }
        s.append(buffer, istr.gcount());
    }
 
 
 
    template <class T>
    static
    void convert(const std::string &s, T & dst);
 
 
    template <class T>
    static
    T convert(const std::string &s);
 
 
    template <class T>
    static
    std::string & import(const T & src, std::string & target);
 
 
 
 
//private: CONSIDER!
 
 
    template <class T>
    static
    const T & lazyConvert(const std::string &s, T & tmp);
 
private:
 
    template <class T>
    static
    void appendString(T & sequence, const std::string & str){
        typename T::value_type tmp;
        sequence.insert(sequence.end(), StringTools::lazyConvert(str, tmp));
    }
 
    template <class T>
    static
    void appendSubstring(T & sequence, const std::string & str, std::string::size_type pos, std::string::size_type n){
 
        if (n > 0){
            appendString(sequence, str.substr(pos, n));
        }
        else {
            appendString(sequence, "");
        }
 
    }
 
};
 
// TODO: consider (optional) skipping empties
template <class T, class C>
void StringTools::split(const std::string & str, T & sequence, const C & separators, const std::string & trimChars){
 
    sequence.clear();
 
    const bool TRIM = !trimChars.empty();
    const std::string::size_type n = str.size();
 
    std::string::size_type pos1 = 0; // Start of segment
    std::string::size_type pos2 = n; // std::string::npos;  // End of segment (index of last char + 1)
 
    // TODO: consider (optional) skipping empties
    //int segmentCount=0;
 
    if (false){ //separators.empty()){ // = no split! :-)
 
        if (TRIM){
            StringTools::trimScan(str, pos1, pos2, trimChars);
            appendSubstring(sequence, str, pos1, pos2-pos1);
        }
        else
            appendString(sequence, str);
 
        return; //  0;
    }
    else {
 
        // Index of the next separator position
        std::string::size_type pos = pos1; // "irreversible"
 
        while (true) {
 
            pos1 = pos;
            pos  = str.find_first_of(separators, pos);
            if (pos == std::string::npos){
                pos2 = n;
                if (TRIM){
                    StringTools::trimScan(str, pos1, pos2, trimChars);
                }
                appendSubstring(sequence, str, pos1, pos2-pos1);
                return; //  segmentCount;
            }
            else {
                pos2 = pos;
                if (TRIM){
                    StringTools::trimScan(str, pos1, pos2, trimChars);
                }
                appendSubstring(sequence, str, pos1, pos2-pos1);
                pos  = str.find_first_not_of(trimChars, pos+1); // if separator is space, or other also in trimChars
                //pos  = str.find_last_not_of(trimChars, pos);
                //++pos; // for the next round
            }
 
        }
    }
}
 
/*
template <>
bool StringTools::split2(const std::string & s, std::string & first, std::string & second, const char *separators, const std::string & trimChars);
*/
 
template <class T1, class T2, class S>
bool StringTools::split2(const std::string & s, T1 & first, T2 & second, const S & separators, const std::string & trimChars){
 
    std::size_t i = s.find_first_of(separators);
 
    if (i != std::string::npos){ // input of type "key=value" found
 
        std::string srcFirst(s, 0, i);
        ++i;
        std::string srcSecond(s, std::min(s.size(), i));
 
        if (!trimChars.empty()){
            first = lazyConvert(StringTools::trim(srcFirst, trimChars), first); // first=first should not clear the object!
        }
        else {
            first = lazyConvert(srcFirst, first); // Note: first=first should not clear the object!
        }
 
        if (!srcSecond.empty()){
            if (!trimChars.empty()){
                second = lazyConvert(StringTools::trim(srcSecond), second);
            }
            else {
                second = lazyConvert(srcSecond, second);
            }
        }
 
        /*
        ++i;
        if (i<s.size()){
            //std::cerr << "toka " << s.substr(i) << '\n';
            if (!trimChars.empty()){
                // sstr2 << StringTools::trim(s.substr(i), trimChars);
                // sstr2 >> second;
                second = lazyConvert(StringTools::trim(s.substr(i), trimChars), second);
            }
            else {
                // sstr2 << s.substr(i);
                // sstr2 >> second;
                second = lazyConvert(s.substr(i), second);
            }
        }
        */
        return true;
    }
    else {
        // std::stringstream sstr;
        if (trimChars.empty()){
            //sstr << s;
            //sstr >> first;
            first = lazyConvert(s, first);
        }
        else {
            // sstr << StringTools::trim(s, trimChars);
            // sstr >> first;
            first = lazyConvert(StringTools::trim(s, trimChars), first);
        }
        return false;
    }
 
 
}
 
 
 
 
 
 
 
template <>
inline
const std::string & StringTools::lazyConvert(const std::string &str, std::string & tmp){
    return str;
}
 
 
template <class T>
inline
const T & StringTools::lazyConvert(const std::string &str, T & dst){
    std::stringstream sstr(str);
    sstr >> dst;
    return dst;
}
 
template <class T>
inline
void StringTools::convert(const std::string &str, T & dst){
    dst = lazyConvert(str, dst);
}
 
 
template <class T>
inline
T StringTools::convert(const std::string &s){
    T tmp;
    tmp = lazyConvert(s, tmp);
    return tmp;
}
 
 
 
 
template <>
inline
std::string & StringTools::import(const std::string & src, std::string & dst){
    dst = src;
    return dst;
}
 
template <class T>
std::string & StringTools::import(const T & x, std::string & dst){
    std::stringstream sstr;
    sstr << x;
    dst.assign(sstr.str());
    //std::cerr << __FUNCTION__ << ": " << str << '>' << target << '\n';
    return dst;
}
 
 
} // drain::
 
#endif /* STRING_H_ */