StringMapper.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)
*/
 
#ifndef STRINGMAPPER_H_
#define STRINGMAPPER_H_
 
#include <drain/Log.h>
#include <map>
#include <list>
#include <iterator>
#include <sstream>
 
#include <drain/RegExp.h>
#include <drain/Sprinter.h>
#include <drain/StringTools.h>
 
#include "IosFormat.h"
#include "Time.h"
#include "VariableFormatter.h"
 
namespace drain {
 
 
//template<class T>
// Todo: rename VariableMapper
class Stringlet: public std::string {
public:
 
    inline
    Stringlet(const std::string & s = "", bool isVariable = false) : std::string(s), isVar(isVariable) {
    };
 
    Stringlet(const Stringlet & s) : std::string(s), isVar(s.isVar) {
    }
 
    inline
    bool isVariable() const { return isVar; };
 
    inline
    void setVariable(bool isVariable=true) { isVar = isVariable; };
 
    inline
    void setLiteral(const std::string &s) { assign(s); isVar = false; };
 
    // Consider!
    // But has to share variable syntax ${...} with string mapper(s), which recognizes it...
    // std::ostream & toStream(std::ostream & ostr, std::map<std::string, T> & environment, bool clearMissing=true){}
 
protected:
 
    bool isVar;
 
};
 
 
inline
std::ostream & operator<<(std::ostream & ostr, const Stringlet & s) {
    if (s.isVariable())
        return ostr << "${" << (const std::string &) s << "}";
    else
        return ostr << (const std::string &) s;
}
 
 
 
/*
template <class T>
class VariableHandler {
 
public:
 
    inline virtual
    ~VariableHandler(){};
 
    IosFormat iosFormat;
 
 
    //  Return false, if variable not found.
    //  Then, further processors may handle the variable tag (remove, change, leave it).
    virtual
    bool handle(const std::string & key, const std::map<std::string,T> & variables, std::ostream & ostr) const {
 
        drain::Logger mout(__FILE__, __FUNCTION__);
 
        std::string k,format;
        drain::StringTools::split2(key, k, format, '|');
        // mout.attention("split '", key, "' to ", k, " + ", format);
 
        const typename std::map<std::string,T>::const_iterator it = variables.find(k);
        if (it == variables.end()) {
            return false;
        }
 
 
        if (format.empty()){
            iosFormat.copyTo(ostr);
            //vostr.width(width);
            //vstd::cerr << __FILE__ << " assign -> " << stringlet << std::endl;
            //vstd::cerr << __FILE__ << " assign <---- " << mit->second << std::endl;
            ostr <<  it->second;
            return true;
        }
        else {
            // mout.attention("delegating '", k, "' to formatVariable: ", format);
            return formatVariable(k, variables, format, ostr);
        }
 
    }
 
 
 
    // NOTE: must return false, if not found. Then, further processors may handle the variable tag (remove, change, leave it).
    virtual
    bool formatVariable(const std::string & key, const std::map<std::string,T> & variables, const std::string & format, std::ostream & ostr) const {
 
        drain::Logger mout(__FILE__, __FUNCTION__);
 
 
        const char firstChar = format.at(0);
        const char lastChar = format.at(format.size()-1);
 
        if (firstChar == ':'){
 
            // mout.attention("substring extraction:", format);
 
            std::string s;
            drain::MapTools::get(variables, key, s);
 
            std::vector<size_t> v;
            drain::StringTools::split(format, v, ':');
            size_t pos   = 0;
            size_t count = s.size();
 
            switch (v.size()) {
                case 3:
                    count = v[2];
                    // no break
                case 2:
                    pos = v[1];
                    if (pos >= s.size()){
                        mout.warn("index ", pos, " greater than size (", s.size(), ") of string value '", s, "' of '", key, "'");
                        return true;
                    }
                    count = std::min(count, s.size()-pos);
                    ostr << s.substr(v[1], count);
                    break;
                default:
                    mout.warn("unsupported formatting '", format, "' for variable '", key, "'");
                    mout.advice("use :startpos or :startpos:count for substring extraction");
            }
            return true;
 
        }
        else if (firstChar == '%'){
 
            // mout.attention("string formatting: ", format);
 
            //else if (format.find('%') != std::string::npos){
            std::string s;
            drain::MapTools::get(variables, key, s);
 
            const size_t BUFFER_SIZE = 256;
            char buffer[BUFFER_SIZE];
            buffer[0] = '\0';
            size_t n = 0;
 
            switch (lastChar){
            case 's':
                n = std::sprintf(buffer, format.c_str(), s.c_str());
                break;
            case 'c':
                n = std::sprintf(buffer, format.c_str(), s.at(0)); // ?
                break;
            case 'p':
                mout.unimplemented("pointer type: ", format);
                break;
            case 'f':
            case 'F':
            case 'e':
            case 'E':
            case 'a':
            case 'A':
            case 'g':
            case 'G':
            {
                double d = NAN; //nand();
                drain::MapTools::get(variables, key, d);
                // ostr << d << '=';
                n = std::sprintf(buffer, format.c_str(), d);
            }
            break;
            case 'd':
            case 'i':
            case 'o':
            case 'u':
            case 'x':
            case 'X':
            {
                int i = 0;
                drain::MapTools::get(variables, key, i);
                ostr << i << '=';
                n = std::sprintf(buffer, format.c_str(), i);
            }
            break;
            default:
                mout.warn("formatting '", format, "' requested for '", key, "' : unsupported type key: ", lastChar);
            }
 
            ostr << buffer;
            if (n > BUFFER_SIZE){
                mout.fail("formatting with '", format, "' exceeded buffer size (", BUFFER_SIZE, ')');
            }
 
            // mout.warn("time formatting '", format, "' requested for '", k, "' not ending with 'time' or 'date'!");
        }
 
        return true;
    }
 
 
};
*/
 
 
 
 
class StringMapper : public std::list<Stringlet> {
 
public:
 
 
    StringMapper(
            const std::string & format = "",
            const std::string & validChars = "[a-zA-Z0-9_]+",
            bool formatting=true
            ): formatting(formatting)
    {
        setValidChars(validChars);
        regExp.setFlags(REG_EXTENDED);
        if (!format.empty())
            parse(format);
        //regExp.setFlags(REG_EXTENDED); // ORDER? Should be before parse!?
    };
 
    StringMapper(const RegExp & regexp, bool formatting=true) : formatting(formatting), regExp(regexp)  { // fieldWidth(0),
        // fillChar('0'),
        // ((std::list<Stringlet> &)*this) = mapper;
    }
 
    StringMapper(const StringMapper & mapper) : std::list<Stringlet>(mapper), formatting(mapper.formatting), regExp(mapper.regExp) { //  Buggy: regExp(mapper.regExp) {
    }
 
 
    inline
    StringMapper & setValidChars(const std::string & chars){
        this->validChars = chars;
        /*
        std::stringstream sstr;
        sstr << "^(.*)\\$\\{(" << chars << ")\\}(.*)$";
        regExp.setExpression(sstr.str());
        */
        updateRegExp();
        return *this;
    }
 
 
    inline
    StringMapper & enableFormatting(bool formatting){
        if (this->formatting != formatting){
            this->formatting = formatting;
            updateRegExp();
        }
        else {
            this->formatting = formatting;
        }
        return *this;
    }
 
 
 
 
    StringMapper & parse(const std::string &s, bool convertEscaped = false);
 
    /*
    static
    std::string & convertEscaped(std::string &s);
    */
 
    bool isLiteral() const;
 
 
    inline
    std::ostream &  toStream(std::ostream & ostr) const {
        Sprinter::sequenceToStream(ostr, *this, Sprinter::emptyLayout);
        return ostr;
    }
 
    IosFormat iosFormat;
 
 
 
    template <class T>
    std::ostream &  toStream(std::ostream & ostr, const std::map<std::string,T> & variables, int replace = 0, const VariableFormatter<T> &formatter = VariableFormatter<T>()) const {
 
        for (const Stringlet & stringlet: *this){
 
            if (stringlet.isVariable()){
 
                if (formatter.handle(stringlet, variables, ostr)){
                    // std::cerr << __FILE__ << " ok stringlet variable: " << stringlet << std::endl;
                    // ok, accepted and handled!
                }
                else if (replace){
                    //else if (keepUnknowns){ // = "recycle", add back "${variable}";
                    if (replace < 0)
                        ostr <<  stringlet; // is Variable -> use layout  "${variable}";
                    else
                        ostr << (char)replace;
                    // if zero, skip silently (replace with empty string)
                    /*
                    if (replaceChar<0)
                        ostr << '#' <<  *it << '$'; // is Variable -> use layout  "${variable}";
                    else if (replaceChar>1)
                        ostr << (char)replaceChar;
                    */
                }
                else { // replace == 0
                    // Skip unknown (unfound) key
                }
            }
            else
                ostr << stringlet;
        };
        return ostr;
    }
 
 
    template <class T>
    std::string toStr(const std::map<std::string,T> &m, int replaceChar = -1, const VariableFormatter<T> & formatter = VariableFormatter<T>()) const {
        std::stringstream s;
        toStream(s, m, replaceChar, formatter);
        return s.str();
    }
 
 
    template <class T>
    void expand(const std::map<std::string,T> &m, const VariableFormatter<T> & formatter=VariableFormatter<T>(), bool clear=false) {
        for (auto & entry: *this){
            if (entry.isVariable()){
                std::stringstream s;
                if (formatter.handle(entry, m, s)){
                    entry.setLiteral(s.str());
                }
                else if (clear) {
                    entry.setLiteral("");
                }
            }
        };
    }
 
 
    template <class T>
    std::ostream &  debug(std::ostream & ostr, const std::map<std::string,T> &m ) const {
 
        const VariableFormatter<T> formatter;
 
        ostr << "StringMapper '"<< "', RegExp='" << regExp << "', " <<  size() << " segments:\n";
        //StringMapper::const_iterator it;
        for (const auto & entry: *this){
            ostr << "  ";
            if (entry.isVariable()){
                ostr  << entry << "=";
                if (!formatter.handle(entry, m, ostr)){
                    ostr << "???";
                }
            }
            else {
                // Literal
                ostr << "'" << entry << "'";
            }
            ostr << '\n';
        };
 
        /*
        for (StringMapper::const_iterator it = begin(); it != end(); it++){
            //ostr << *it;
            ostr << '\t';
            if (it->isVariable()){
                //ostr << "VAR: ";
                typename std::map<std::string, T >::const_iterator mit = m.find(*it);
                if (mit != m.end())
                    ostr << "\"" <<  mit->second << "\"";
                else
                    ostr << *it;
            }
            else {
                ostr << "'"<<  *it << "'";
                //ostr << "LIT: '" << *it << "'\n";
            }
            ostr << '\n';
            //ostr << '\n';
        }
        */
        return ostr;
    }
 
 
protected:
 
    inline
    void updateRegExp(){
        std::stringstream sstr;
        sstr << "^(.*)\\$\\{(" << validChars; //  << ")\\}(.*)$";
        if (formatting){
             sstr << "(\\|[^}]*)?";
        }
        sstr << ")\\}(.*)$";
        // std::cout << sstr.str() << '\n';
        regExp.setExpression(sstr.str());
    }
 
    StringMapper & parse(const std::string &s, RegExp &r);
 
    std::string validChars;
    bool formatting;
 
    RegExp regExp;
    //  | REG_NEWLINE |  RE_DOT_NEWLINE); // | RE_DOT_NEWLINE); //  | REG_NEWLINE |  RE_DOT_NEWLINE
 
};
 
inline
std::ostream & operator<<(std::ostream & ostr, const StringMapper & strmap){
    return strmap.toStream(ostr);
}
 
 
} // NAMESPACE
 
#endif /* STRINGMAPPER_H_ */
 
// Drain