Cloner.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 Cloner_H_
#define Cloner_H_
 
//#include <list>
#include <map>
#include <exception>
#include <iostream>
#include <sstream>
 
namespace drain {
 
template <class T>
struct ClonerBase {
 
 
    typedef size_t index_t;
 
    // If
    typedef std::pair<index_t, T*> entry_t;
 
    ClonerBase(){};
 
    virtual
    ~ClonerBase(){
    };
 
 
    virtual
    T & getCloned() const = 0;  // could be const (if mutable ptrs )
 
    virtual
    entry_t getClonerEntry() const = 0;
 
 
    // virtual const T & getCloned(index_t i) const = 0;
 
    virtual
    T & getCloned(index_t i) const = 0;
 
 
    virtual
    const T & getSource() const = 0;
 
    virtual
    T & getSource() = 0;
 
 
 
    // Return the number of cloned instances.
    virtual
    size_t count() const = 0;
 
 
    virtual // clear
    bool drop(index_t i) const = 0;
 
 
    //experimental
    // virtual  bool dropUnique() = 0;
 
    protected:
 
 
 
};
 
 
 
template <class B, class S>
struct Cloner : public ClonerBase<B> {
 
    typedef ClonerBase<B> clonerbase_t;
 
    // "inherit" a type
    typedef typename clonerbase_t::index_t index_t;
 
    // "inherit" a type
    typedef typename clonerbase_t::entry_t entry_t;
 
    typedef std::map<index_t,S *> ptr_container_t;
 
 
    Cloner(){};
 
    Cloner(const Cloner<B,S> & c) : src(c.src){
    };
 
    Cloner(const S & s) : src(s){
    };
 
    virtual
    ~Cloner(){
        for (typename ptr_container_t::iterator it=ptrs.begin(); it!= ptrs.end(); ++it){
            //std::cerr << "deleting instance, id=" << it->first << '\n';
            delete it->second;
        }
    };
 
    B & getCloned() const {
        return getClonedSrc();
    };
 
 
    /*
     *
    virtual
    const B & getCloned(index_t i) const {
        typename ptr_container_t::const_iterator it = ptrs.find(i);
        if (it == ptrs.end()){
            std::stringstream sstr;
            sstr << __FILE__ << ':' << __FUNCTION__ << ": index not found: "<< i;
            throw std::runtime_error(sstr.str());
        }
        return *it->second;
    };
    */
 
    /*
     *  \param i - index (id) of the instance.
     */
    virtual
    B & getCloned(index_t i) const {
        typename ptr_container_t::iterator it = ptrs.find(i);
        if (it == ptrs.end()){
            std::stringstream sstr;
            sstr << __FILE__ << ':' << __FUNCTION__ << ": index not found: "<< i;
            throw std::runtime_error(sstr.str());
        }
        return *it->second;
    };
 
 
    S & getClonedSrc() const{
        S *ptr = new S(src);  // NOTE: parameterReferences must be done
        //this->ptrs.insert(ptr); //push_front(p);
        this->ptrs[getNewIndex()] = ptr;
        return *ptr;
    };
 
 
    virtual
    entry_t getClonerEntry() const {
        S *ptr = new S(src);  // NOTE: parameterReferences must be done
        index_t i = getNewIndex();
        this->ptrs[i] = ptr; //.insert(ptr); //push_front(p);
        return entry_t(i, ptr);
    };
 
 
    /* Consider separating these to "Provider" or "Factory" etc. */
 
    /*
     *  The returned object is possibly static.
     */
    virtual
    const B & getSource() const {
        return getSourceOrig();
    };
 
    /*
     *  The returned object is possibly static.
     */
    virtual
    B & getSource() {
        return getSourceOrig();
    };
 
    /*
     *  The returned object is possibly static.
     */
    virtual
    const S & getSourceOrig() const {
        return src;
    };
 
    /*
     *  The returned object is possibly static.
     */
    virtual
    S & getSourceOrig() {
        return src;
    };
 
 
    virtual inline
    size_t count() const {
        return ptrs.size();
    }
 
 
    virtual inline  // clear
    bool drop(index_t i) const override {
 
        const typename ptr_container_t::iterator it = ptrs.find(i);
 
        if (it != ptrs.end()){
            // std::cout << "deleting " << *ptr << ", at #" << (long int)ptr << '\n';
            // std::cout << "deleting " << (long int)ptr << '\n';
            delete it->second;
            ptrs.erase(it);  // TODO!
            return true;
        }
        else {
            std::cerr << "already deleted or does not exist: " << i << '\n';
            // warn?
            return false;
        }
 
    }
 
 
    //protected:
 
    //  static S entry;  // Consider non-static
    S src;  // Consider non-static
 
    /*
    inline
    void clear(){
        for (typename ptr_container_t::iterator it=ptrs.begin(); it!= ptrs.end(); ++it){
            S *ptr = *it;
            std::cout << "deleting " << *ptr << ", at #" << (long int)ptr << '\n';
            delete ptr;
        }
        ptrs.clear();
    }
    */
 
 
 
protected:
 
    // TODO: re-allocate empty slots
    inline
    index_t getNewIndex() const {
        // pra gma omp critical
        {
            if (this->ptrs.empty())
                return 1;
            else {
                // std::cerr << "getNewIndex: " << this->ptrs.rbegin()->first << '\n';
                return this->ptrs.rbegin()->first + 1;
            }
        }
    }
 
    // Structure for storing pointers until the target objects should be deleted.
    mutable
    ptr_container_t ptrs;
 
 
};
 
 
 
 
}
 
#endif /* Cloner_H_ */
 
// Drain