helloworld.cpp

/*
*   helloworld.cpp
*/
#include <iostream>
#include <string>
#include <functional>
#include <algorithm>
#include <unordered_map>


class SecretMessage : private std::string
{
    private: typedef std::unordered_map<std::string, char> hashtable;
    private: typedef std::function<void(char)> callback;


    public: class Cypher : hashtable
    {
        friend class SecretMessage;

        private: uint8_t __chunk_size;

        public: Cypher(std::string const &key)
            : hashtable()
        {
            parse(key);
        }

        public: Cypher &parse(std::string const &key)
        {
            size_t key_offset = key.find(' ');
            uint8_t size = (uint8_t) std::stoi(key.substr(0, key_offset));
            uint8_t ichar = 0;
            __chunk_size = size;
            for (size_t i = key_offset + 1; i < key.size(); i += size)
            {
                std::string const &key_chunk = key.substr(i, size);
                insert({key_chunk, (char) ichar});
                ++ichar;
            }
            return *this;
        }
    };


    public: class Printer : private std::string
    {
        public: Printer()
            : std::string()
        {
        }

        public: Printer &print(char c)
        {
            if (size() == 0 || back() == ' ')
                c = toupper(c);
            else
                c = tolower(c);
            push_back(c);
            std::cout << c;
            return *this;
        }
    };


    private: std::string __decrypted;


    public: SecretMessage(std::string const &msg)
        : std::string()
    {
        for (auto const &c : msg)
            if (c != ' ')
                push_back(c);
    }


    public: SecretMessage &unlock(Cypher const &cypher)
    {
        __decrypted.clear();
        for (size_t i = 0; i < size(); i += cypher.__chunk_size)
        {
            std::string const &chunk = substr(i, cypher.__chunk_size);
            char c = cypher.at(chunk);
            __decrypted.push_back(c);
        }
        return *this;
    }

    public: SecretMessage &traverse_characters(callback on_traverse)
    {
        for (auto const &c : __decrypted)
            on_traverse(c);
        return *this;
    }
};


int main()
{
    SecretMessage::Printer printer;

    SecretMessage(
            "74OR!xE-tl6BF@~B"
            "vD%dH!+vvD%dH!+v"
            "3/c\\;c2t^-;n\\,"
            "Z,jP4km65Qae+WF!"
            "J/3/c\\;c2twbMAy"
            "(3.vD%dH!+vTLH&V"
            "Bf7XzvMJWC!     "
        )
        .unlock(
            SecretMessage::Cypher(
                "8 DI[KtkwZmUf2E'Kc!*g)jpjO_Ti!@H"
                "P;=vpYo_X~`;`ew1]g9$I`psz#zG9(uQ"
                "Yy4jw'=oh\\q[sVgJmA6Rzze-ad~1N41"
                "#xeYEBm8;qXWZScPEgL/q,pfy^/Qtr~M"
                "t$F'MnoG$)P-SDuOq(D$JlDsfUTci+vi"
                "eV=]ko,+&p&NF\\a50%((`$HNC,3srm]"
                "rRcCd8t5AglNPaZ6xrum@B_Ol2LEHdyX"
                "SwS5,.=^dT4HF].Fv.OjC0XiR4s+&hxh"
                "bmDKjP4km65QXzvMJWC!I(kNclilR\\W"
                "=)GtYK#aUQjBz5c*[kSIa2u~/`KRxG3u"
                "waYbGl~Q9Y/NwLy0@(+#qe'J1_A79kV'"
                "J^aQ^^-;n\\,Z,#o]WBzo1;!h83]J$19"
                "bT6I6`),E_,ddrxWPPqF&)JX1#h3-so@"
                "^rW*=J[C50Z^y0AA!y4uWS%K#$7[AIh^"
                "UZ&)9M+2AIKUk_aHdG~Onb0N8b#L*@8g"
                "K+'D/oVpCfTi8un7VS/XF]im)C.7G6OY"
                "j.L9;iMn&%X`rnf5Gx0M14Zx-3[b_pg="
                "@*]nMfTLH&VBf7tl6BF@~BSeF-CVH'U_"
                "RjD~TR74OR!xE-uQq;2PvV.OTg*8.kb6"
                "3lz5'2vD%dH!+v\\%LQIh\\W*+(snN@*"
                "3/c\\;c2tBweE9%0hp&7LU=e%wbMAy(3"
                ".r)/t-v`8EsY7%\\[Uyf2q$Z![w1JsSX"
                "fKae+WF!J/3KzqE=M+[nO.QZm2zOPQU+"
                "=al6B7xW/9)t=+d[lHY9th(JgScSq6[t"
                "~@2L4,)biI4Wg&gjWWW.TZOhRtQ'[f]U"
                "Dn9DEOR#vm'=90fH]&5/H~~$8qr5$E@I"
                "*QN!`-^)L56$\\2i.TCyoNTmT@fD,8ao"
                "\\;PV0cKXs\\~BQlv'c1(epRz3V+'Zjp"
                ")`irp-u!Uh,ac*T1eK(dV_Aep%S^[+*2"
                "bn*7iSij/V7t$fZK@2eHTgBdCq~b*MI%"
                "'AL3LH_wFkn21idL901Ox.Vimr8'wRYX"
                "#zvNkUgWX-NnM\\[5$_mGgEw_=sKX3JH"
                "A_*G[Y&E7V4lu_"
            )
        )
        .traverse_characters(
            [&](char c){printer.print(c);}
        );

    return 0;
}