// Copyright (C) 2010, Guy Barrand. All rights reserved.
// See the file tools.license for terms.

#ifndef tools_wroot_ntuple
#define tools_wroot_ntuple

// An ntuple class to write at the ROOT format.
// It inherits wroot::tree and each column is mapped
// on a wroot::branch. Each add_row() does a tree::fill().

#include "tree"

#include "../vfind"
#include "../vmanip"
#include "../ntuple_booking"
#include "../sout"
#include "../scast"
#include "../forit"

namespace tools {
namespace wroot {

class ntuple : public tree {
protected:
  class icol {
  public:
    virtual ~icol(){}
  public:
    virtual void* cast(cid) const = 0;
    virtual cid id_cls() const = 0;
  public:
    virtual void add() = 0;
    virtual const std::string& name() const = 0;
    virtual void set_basket_size(uint32) = 0;
  };
  
public:
  template <class T>
  class column : public virtual icol {
  public:
    static cid id_class() {
      static const T s_v = T(); //do that for T = std::string.
      return _cid(s_v);
    }
    virtual void* cast(cid a_class) const {
      if(void* p = cmp_cast<column>(this,a_class)) {return p;}
      else return 0;
    }
    virtual cid id_cls() const {return id_class();}
  public: //icol
    virtual void add() {m_leaf->fill(m_tmp);m_tmp = m_def;}
    virtual const std::string& name() const {return m_leaf->name();}
    virtual void set_basket_size(uint32 a_size) {
      m_leaf->branch().set_basket_size(a_size);
    }
  public:
    column(tree& a_tree,const std::string& a_name,const T& a_def)
    :m_tree(a_tree),m_leaf(0)
    ,m_def(a_def),m_tmp(a_def)
    {
      branch* br = m_tree.create_branch(a_name);
      m_leaf = br->create_leaf<T>(a_name,a_name);
    }
    virtual ~column(){}
  protected:
    column(const column& a_from)
    :icol(a_from)
    ,m_tree(a_from.m_tree) 
    ,m_leaf(0)
    ,m_def(a_from.m_def)
    ,m_tmp(a_from.m_tmp)    
    {}
    column& operator=(const column& a_from){
      if(&a_from==this) return *this;
      m_leaf = 0;
      m_def = a_from.m_def;
      m_tmp = a_from.m_tmp;
      return *this;
    }
  public:
    bool fill(const T& a_value) {m_tmp = a_value;return true;}
  protected:
    tree& m_tree;
    leaf<T>* m_leaf;
    T m_def;
    T m_tmp;
  };

public:
  ntuple(idir& a_dir,const std::string& a_name,const std::string& a_title)
  :tree(a_dir,a_name,a_title){}

  ntuple(idir& a_dir,const ntuple_booking& a_bkg)
  :tree(a_dir,a_bkg.m_name,a_bkg.m_title){
    const std::vector<ntuple_booking::col_t>& cols = a_bkg.m_columns;
    tools_vforcit(ntuple_booking::col_t,cols,it){

      if((*it).second==_cid(char(0))) {
        create_column<char>((*it).first);
      } else if((*it).second==_cid(short(0))) {
        create_column<short>((*it).first);
      } else if((*it).second==_cid(int(0))) {
        create_column<int>((*it).first);
      } else if((*it).second==_cid(float(0))) {
        create_column<float>((*it).first);
      } else if((*it).second==_cid(double(0))) {
        create_column<double>((*it).first);

      // no leaf_store_class() defined for the other types.

      } else {
        m_out << "tools::wroot::ntuple :"
              << " for column " << sout((*it).first)
              << ", type with cid " << (*it).second << " not yet handled."
              << std::endl;
        //throw
        tools::clear<icol>(m_cols);
        tools::clear<branch>(m_branches);
        return;
      }      
    }
  }

  virtual ~ntuple() {}
protected:
  ntuple(const ntuple& a_from)
  :iobject(a_from),itree(a_from),tree(a_from)
  {}
  ntuple& operator=(const ntuple&){return *this;}
public:
  const std::vector<icol*>& columns() const {return m_cols;}

  template <class T>
  column<T>* create_column(const std::string& a_name,const T& a_def = T()) {
    if(find_named<icol>(m_cols,a_name)) return 0;
    column<T>* col = new column<T>(*this,a_name,a_def);
    if(!col) return 0;
    m_cols.push_back(col);
    return col;
  }

  template <class T>
  column<T>* find_column(const std::string& a_name) {
    icol* col = find_named<icol>(m_cols,a_name);
    if(!col) return 0;
    return id_cast<icol, column<T> >(*col);
  }

  bool add_row() {
    if(m_cols.empty()) return false;
    tools_vforit(icol*,m_cols,it) (*it)->add();
    uint32 n;
    return tree::fill(n);
  }
  void set_basket_size(uint32 a_size) {
    tools_vforit(icol*,m_cols,it) (*it)->set_basket_size(a_size);
  }
protected:
  std::vector<icol*> m_cols;
};

}}

#endif