/*===========================================================================
*
*                            PUBLIC DOMAIN NOTICE
*               National Center for Biotechnology Information
*
*  This software/database is a "United States Government Work" under the
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/*****************************************************************************
 *   GATB : Genome Assembly Tool Box
 *   Copyright (C) 2014  INRIA
 *   Authors: R.Chikhi, G.Rizk, E.Drezen
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as
 *  published by the Free Software Foundation, either version 3 of the
 *  License, or (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
*****************************************************************************/

/** \file Integer.hpp
 *  \date 01/03/2013
 *  \author edrezen
 *  \brief Entry point class for large integer usage
 */
#ifndef _GATB_CORE_TOOLS_MATH_INTEGER_HPP_
#define _GATB_CORE_TOOLS_MATH_INTEGER_HPP_

/********************************************************************************/
#include "LargeInt.hpp"
#include "Model.hpp"
#include "KmerInit.hpp"
#include <boost/variant.hpp>
#include <deque>

/********************************************************************************/
namespace DeBruijn {
/********************************************************************************/


/** \brief Class for large integers calculus
 *
 * The IntegerTemplate is implemented as a boost variant, which means that it can act like T1, T2, T3... type
 * according to the configuration.
 *
 * The IntegerTemplate should be specialized with 4 different LargeInt implementation
 * classes.
 *
 * All the methods are implemented through a boost variant visitor.
 *
 *  According to the INTEGER_KIND compilation flag, we define the Integer class
 *  as an alias of one from several possible implementations.
 *
 *  Note that we have 2 possible native implementations (NativeInt64 and NativeInt128)
 *  that rely on native types uint64_t and __uint128_t.
 *
 *  For larger integer, a multi-precision LargeInt is used.
 *
 *  From the user point of view, [s]he has just to include this file and use the Integer
 *  class.
 *
 */


class IntegerTemplate
{
public:
    typedef TLargeIntN Type;
    operator Type() const { return v; }

    IntegerTemplate() : v(LargeInt<MaxPrec>(0)) {}

    static int MaxKmer() { return 32*MaxPrec; }

    IntegerTemplate(int kmer_len, uint64_t n) {
        int p = (kmer_len+31)/32;
        v = CreateVariant<TLargeIntN, LargeInt>(p);
        *this = *this + n;
    }

    IntegerTemplate(std::string::const_iterator begin, std::string::const_iterator end) : IntegerTemplate(end-begin, 0)  {
        for(auto i = begin; i != end; ++i) {
            *this = (*this) << 2;
            *this = *this + (std::find(bin2NT.begin(), bin2NT.end(), *i) - bin2NT.begin());
        }
    }    
    IntegerTemplate(const std::string& kmer) : IntegerTemplate(kmer.begin(), kmer.end()) {}

    IntegerTemplate(std::deque<char>::const_iterator begin, std::deque<char>::const_iterator end) : IntegerTemplate(end-begin, 0)  {
        for(auto i = begin; i != end; ++i) {
            *this = (*this) << 2;
            *this = *this + (std::find(bin2NT.begin(), bin2NT.end(), *i) - bin2NT.begin());
        }
    }
    IntegerTemplate(std::vector<char>::const_iterator begin, std::vector<char>::const_iterator end) : IntegerTemplate(end-begin, 0)  {
        for(auto i = begin; i != end; ++i) {
            *this = (*this) << 2;
            *this = *this + (std::find(bin2NT.begin(), bin2NT.end(), *i) - bin2NT.begin());
        }
    }
    

    /**Construct from a different size IntegerTemplate
       Will clip (or add) extra nucs on the LEFT of the string
    */
    IntegerTemplate(IntegerTemplate other, int kmer_len) : IntegerTemplate(kmer_len, 0) {  // construct correct type
        uint64_t* p = getPointer();
        uint64_t* other_p = other.getPointer();
        size_t prec = (kmer_len+31)/32;         // number of 8-byte words significant for new kmer
        size_t other_prec = other.getSize()/64; // number of 8-byte words in old kmer (could have some extra 0s)
        copy(other_p, other_p+std::min(prec,other_prec), p);
        int partial_part_bits = 2*(kmer_len%32);
        if(partial_part_bits > 0) {
            uint64_t mask = (uint64_t(1) << partial_part_bits) - 1;
            p[prec-1] &= mask;
        }
    }

    /** Copy constructor. Relies on the copy constructor of boost variant
     * \param[in] t : the object to be used for initialization
     */
    template<typename T>  explicit IntegerTemplate (const T& t) : v (t)  {}

    /** Affectation operator. Relies on the affectation operator of boost variant
     * \param[in] t : object to be copied
     * \return the current object.
     */
    template<typename T>
    IntegerTemplate& operator=(const T& t)
    {
        v = t;
        return *this;
    }

    /** Get the name of the class used by the variant (ie. one of the Ti template class parameters)
     * \return the class name.
     */
    const char*  getName () const { return boost::apply_visitor (Integer_name(),  *(*this)); }

    /** Get the size of an instance of the class used by the variant  (ie. one of the Ti template class parameters)
     * \return the size of an object (in bits).
     */
    const size_t getSize () const { return boost::apply_visitor (Integer_size(),  *(*this)); }

    /** Operator +
     * \param[in] a : first operand
     * \param[in] b : second operand
     * \return sum of the two operands.
     */
    inline friend IntegerTemplate   operator+  (const IntegerTemplate& a, const IntegerTemplate& b)  {  return  boost::apply_visitor (Integer_plus(),  *a, *b);  }
    inline friend IntegerTemplate   operator+  (const IntegerTemplate& a, uint64_t b)  {  return  boost::apply_visitor (Number_plus(b),  *a);  }

    /** Operator -
     * \param[in] a : first operand
     * \param[in] b : second operand
     * \return substraction of the two operands.
     */
    inline friend IntegerTemplate   operator-  (const IntegerTemplate& a, const IntegerTemplate& b)  {  return  boost::apply_visitor (Integer_minus(), *a, *b);  }

    /** Operator |
     * \param[in] a : first operand
     * \param[in] b : second operand
     * \return 'or' of the two operands.
     */
    inline friend IntegerTemplate   operator|  (const IntegerTemplate& a, const IntegerTemplate& b)  {  return  boost::apply_visitor (Integer_or(),    *a, *b);  }

    /** Operator ^
     * \param[in] a : first operand
     * \param[in] b : second operand
     * \return 'xor' of the two operands.
     */
    inline friend IntegerTemplate   operator^  (const IntegerTemplate& a, const IntegerTemplate& b)  {  return  boost::apply_visitor (Integer_xor(),   *a, *b);  }

    /** Operator &
     * \param[in] a : first operand
     * \param[in] b : second operand
     * \return 'and' of the two operands.
     */
    inline friend IntegerTemplate   operator&  (const IntegerTemplate& a, const IntegerTemplate& b)  {  return  boost::apply_visitor (Integer_and(),   *a, *b);  }

    /** Operator ~
     * \param[in] a : operand
     * \return negation of the operand
     */
    inline friend IntegerTemplate   operator~  (const IntegerTemplate& a)                    {  Integer_compl v; return  boost::apply_visitor (v, *a);  }

    /** Operator ==
     * \param[in] a : first operand
     * \param[in] b : second operand
     * \return equality of the two operands.
     */
    inline friend bool      operator== (const IntegerTemplate& a, const IntegerTemplate& b)  {  return  boost::apply_visitor (Integer_equals(), *a, *b);  }

    /** Operator !=
     * \param[in] a : first operand
     * \param[in] b : second operand
     * \return inequality of the two operands.
     */
    inline friend bool      operator!= (const IntegerTemplate& a, const IntegerTemplate& b)  {  return  ! (*a==*b);  }

    /** Operator <
     * \param[in] a : first operand
     * \param[in] b : second operand
     * \return '<' of the two operands.
     */
    inline friend bool      operator<  (const IntegerTemplate& a, const IntegerTemplate& b)  {  return  boost::apply_visitor (Integer_less(),   *a, *b);  }

    /** Operator <=
     * \param[in] a : first operand
     * \param[in] b : second operand
     * \return '<=' of the two operands.
     */
    inline friend bool      operator<= (const IntegerTemplate& a, const IntegerTemplate& b)  {  return  boost::apply_visitor (Integer_lesseq(), *a, *b);  }


    /** Operator /
     * \param[in] a : first operand
     * \param[in] c : second operand
     * \return division of the two operands.
     */
    inline friend IntegerTemplate   operator/  (const IntegerTemplate& a, const u_int32_t& c)  {  return  boost::apply_visitor (Integer_div(c),  *a);  }

    /** Operator %
     * \param[in] a : first operand
     * \param[in] c : second operand
     * \return modulo of the two operands.
     */
    inline friend u_int32_t operator%  (const IntegerTemplate& a, const u_int32_t& c)  {  return  boost::apply_visitor (Integer_mod(c),  *a);  }

    /** Operator >>
     * \param[in] a : first operand
     * \param[in] c : second operand
     * \return right shift of the two operands.
     */
    inline friend IntegerTemplate   operator>> (const IntegerTemplate& a, const int& c)  {  return  boost::apply_visitor (Integer_shiftLeft(c),   *a);  }

    /** Operator <<
     * \param[in] a : first operand
     * \param[in] c : second operand
     * \return left shift of the two operands.
     */
    inline friend IntegerTemplate   operator<< (const IntegerTemplate& a, const int& c)  {  return  boost::apply_visitor (Integer_shiftRight(c),  *a);  }

    /** Operator +=
     * \param[in] a : first operand
     * \return addition and affectation.
     */
    IntegerTemplate & operator+= (const IntegerTemplate& a)  {  boost::apply_visitor (Integer_plusaffect(),  *(*this), *a); return *this; }

    /** Operator ^=
     * \param[in] a : first operand
     * \return xor and affectation.
     */
    IntegerTemplate & operator^= (const IntegerTemplate& a)  {  boost::apply_visitor (Integer_xoraffect(),   *(*this), *a); return *this; }

    /** Operator[] access the ith nucleotide in the given integer. For instance a[4] get the 5th nucleotide of
     * a kmer encoded as an Integer object.
     * \param[in] idx : index of the nucleotide to be retrieved
     * \return the nucleotide value as follow: A=0, C=1, T=2 and G=3
     */
    u_int8_t  operator[]  (size_t idx) const   { return  boost::apply_visitor (Integer_value_at(idx), *(*this)); }

    /** Get the reverse complement of a kmer encoded as an IntegerTemplate object. Note that the kmer size must be known.
     * \param[in] a : kmer value to be reversed-complemented
     * \param[in] sizeKmer : size of the kmer
     * \return the reverse complement kmer as a IntegerTemplate value
     */
    friend IntegerTemplate revcomp (const IntegerTemplate& a,  size_t sizeKmer)  {  return  boost::apply_visitor (Integer_revomp(sizeKmer),  *a);  }

    /** Get an ASCII string representation of a kmer encoded as a IntegerTemplate object
     * \param[in] sizeKmer : size of the kmer
     * \return the ASCII representation of the kmer.
     */
    std::string toString (size_t sizeKmer) const  {  return boost::apply_visitor (Integer_toString(sizeKmer), *(*this)); }

    /** Output stream operator for the IntegerTemplate class
     * \param[in] s : the output stream to be used.
     * \param[in] a : the object to output
     * \return the modified output stream.
     */
    friend std::ostream & operator<<(std::ostream & s, const IntegerTemplate& a)  {  s << *a;  return s;  }

    /** Get the value of the IntegerTemplate object as a U type, U being one of the T1,T2,T3,T4
     * template class parameters. This method can be seen as a converter from the IntegerTemplate class
     * to a specific U type (given as a template parameter of this method).
     * \return  the converted value as a U type.
     */
    template<typename U>
    const U& get ()  const  {  return * boost::get<U>(&v);  }

    /** Get pointer to the actual data **/
    uint64_t* getPointer() { return boost::apply_visitor (Pointer(), v); }
    const uint64_t* getPointer() const { return boost::apply_visitor (PointerC(), v); }

    /** Get a hash value on 64 bits for a given IntegerTemplate object.
     * \return the hash value on 64 bits.
     */
    u_int64_t oahash() const { return  boost::apply_visitor (Integer_oahash(), *(*this)); }

protected:
    Type v;
    Type& operator *()       { return v; }
    const Type& operator *() const { return v; }

private:
    struct Integer_oahash : public boost::static_visitor<u_int64_t>    {
        template<typename T>  u_int64_t operator() (const T& a) const  { return a.oahash();  }};

    struct Pointer : public boost::static_visitor<uint64_t*>    {
        template<typename T>  uint64_t* operator() (T& a) const { return a.getPointer(); }};
    struct PointerC : public boost::static_visitor<const uint64_t*>    {
        template<typename T>  const uint64_t* operator() (T& a) const { return a.getPointer(); }};

    struct Integer_name : public boost::static_visitor<const char*>    {
        template<typename T>  const char* operator() (const T& a) const { return a.getName();  }};

    struct Integer_size : public boost::static_visitor<const size_t>    {
        template<typename T>  const size_t operator() (const T& a) const  { return a.getSize();  }};

    struct Integer_plus : public boost::static_visitor<IntegerTemplate>    {
        template<typename T>              IntegerTemplate operator() (const T& a, const T& b) const  { return IntegerTemplate(a + b);  }
        template<typename T, typename U>  IntegerTemplate operator() (const T& a, const U& b) const  { return IntegerTemplate();}
    };

    struct Number_plus : public boost::static_visitor<IntegerTemplate>    {
        Number_plus(uint64_t n) : num(n) {}
        template<typename T> IntegerTemplate operator() (const T& a) const  { return IntegerTemplate(a + T(num));}
        uint64_t num;
    };

    struct Integer_minus : public boost::static_visitor<IntegerTemplate>    {
        template<typename T>              IntegerTemplate operator() (const T& a, const T& b) const  { return IntegerTemplate(a - b);  }
        template<typename T, typename U>  IntegerTemplate operator() (const T& a, const U& b) const  { return IntegerTemplate();  }
    };

    struct Integer_or : public boost::static_visitor<IntegerTemplate>    {
        template<typename T>              IntegerTemplate operator() (const T& a, const T& b) const  { return IntegerTemplate(a | b);  }
        template<typename T, typename U>  IntegerTemplate operator() (const T& a, const U& b) const  { return IntegerTemplate();  }
    };

    struct Integer_xor : public boost::static_visitor<IntegerTemplate>    {
        template<typename T>              IntegerTemplate operator() (const T& a, const T& b) const  { return IntegerTemplate(a ^ b);  }
        template<typename T, typename U>  IntegerTemplate operator() (const T& a, const U& b) const  { return IntegerTemplate();  }
    };

    struct Integer_and : public boost::static_visitor<IntegerTemplate>    {
        template<typename T>              IntegerTemplate operator() (const T& a, const T& b) const  { return IntegerTemplate(a & b);  }
        template<typename T, typename U>  IntegerTemplate operator() (const T& a, const U& b) const  { return IntegerTemplate();  }
    };

    struct Integer_less : public boost::static_visitor<bool>    {
        template<typename T>              bool operator() (const T& a, const T& b) const  { return a < b;  }
        template<typename T, typename U>  bool operator() (const T& a, const U& b) const  { return false;  }
    };

    struct Integer_lesseq : public boost::static_visitor<bool>    {
        template<typename T>              bool operator() (const T& a, const T& b) const  { return a <= b;  }
        template<typename T, typename U>  bool operator() (const T& a, const U& b) const  { return false;   }
    };

    struct Integer_equals : public boost::static_visitor<bool>    {
        template<typename T>              bool operator() (const T& a, const T& b) const  { return a == b;  }
        template<typename T, typename U>  bool operator() (const T& a, const U& b) const  { return false;   }
    };

    struct Integer_plusaffect : public boost::static_visitor<>    {
        template<typename T>              void operator() ( T& a, const T& b) const  { a += b;  }
        template<typename T, typename U>  void operator() ( T& a, const U& b) const  {   }
    };

    struct Integer_xoraffect : public boost::static_visitor<>    {
        template<typename T>              void operator() ( T& a, const T& b) const  { a ^= b;  }
        template<typename T, typename U>  void operator() ( T& a, const U& b) const  {   }
    };

    struct Integer_compl : public boost::static_visitor<IntegerTemplate>    {
        template<typename T>  IntegerTemplate operator() (const T& a)  { return IntegerTemplate(~a);  }};

    template<typename Result, typename Arg>
    struct Visitor : public boost::static_visitor<Result>
    {
        Visitor (Arg a=Arg()) : arg(a) {}
        Arg arg;
    };

    struct Integer_div : public Visitor<IntegerTemplate,const u_int32_t>    {
        Integer_div (const u_int32_t& c) : Visitor<IntegerTemplate,const u_int32_t>(c) {}
        template<typename T>  IntegerTemplate operator() (const T& a) const  { return IntegerTemplate(a/this->arg);  }};

    struct Integer_mod : public Visitor<u_int32_t,const u_int32_t>    {
        Integer_mod (const u_int32_t& c) : Visitor<u_int32_t,const u_int32_t>(c) {}
        template<typename T>  u_int32_t operator() (const T& a) const  { return (a%this->arg);  }};

    struct Integer_shiftLeft : public Visitor<IntegerTemplate,const int>    {
        Integer_shiftLeft (const int& c) : Visitor<IntegerTemplate,const int>(c) {}
        template<typename T>  IntegerTemplate operator() (const T& a) const  { return IntegerTemplate (a >> this->arg);  }};

    struct Integer_shiftRight : public Visitor<IntegerTemplate,const int>    {
        Integer_shiftRight (const int& c) : Visitor<IntegerTemplate,const int>(c) {}
        template<typename T>  IntegerTemplate operator() (const T& a) const  { return IntegerTemplate (a << this->arg);  }};

    struct Integer_revomp : public Visitor<IntegerTemplate,size_t>    {
        Integer_revomp (const size_t& c) : Visitor<IntegerTemplate,size_t>(c) {}
        template<typename T>  IntegerTemplate operator() (const T& a) const  { return IntegerTemplate (revcomp(a,this->arg));  }};

    struct Integer_value_at : public Visitor<u_int8_t,size_t>   {
        Integer_value_at (size_t idx) : Visitor<u_int8_t,size_t>(idx) {}
        template<typename T>  u_int8_t operator() (const T& a) const { return a[this->arg];  }};

    struct Integer_toString : public Visitor<std::string,size_t>   {
        Integer_toString (size_t c) : Visitor<std::string,size_t>(c) {}
        template<typename T>  std::string operator() (const T& a) const  { return a.toString(this->arg);  }};
};



/********************************************************************************/

typedef IntegerTemplate TKmer;

/********************************************************************************/
};
/********************************************************************************/

#endif /* _GATB_CORE_TOOLS_MATH_INTEGER_HPP_ */