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

#ifndef tools_sg_states
#define tools_sg_states

#include "state"

//#define TOOLS_SG_STATES_CUR

namespace tools {
namespace sg {

class states {
public:
#ifdef TOOLS_SG_STATES_CUR
  states(unsigned int a_ww,unsigned int a_wh)
  :m_states(8)
  ,m_state(&(m_states[0]))
  ,m_cur_state(0)
  {
    m_state->m_ww = a_ww;
    m_state->m_wh = a_wh;
  }
#else
  states(unsigned int a_ww,unsigned int a_wh):m_states() {
    m_state.m_ww = a_ww;
    m_state.m_wh = a_wh;
  }
#endif
  virtual ~states(){}
protected:
#ifdef TOOLS_SG_STATES_CUR
  states(const states& a_from)
  :m_states(a_from.m_states)
  ,m_state(&(m_states[a_from.m_cur_state]))
  ,m_cur_state(a_from.m_cur_state)
  ,m_saved_state(a_from.m_saved_state)
  {}
  states& operator=(const states& a_from){
    m_states = a_from.m_states;
    m_state = &(m_states[a_from.m_cur_state]);
    m_cur_state = a_from.m_cur_state;
    m_saved_state = a_from.m_saved_state;
    return *this;
  }
#else
  states(const states& a_from)
  :m_states(a_from.m_states)
  ,m_state(a_from.m_state)
  ,m_saved_state(a_from.m_saved_state)
  {}
  states& operator=(const states& a_from){
    m_states = a_from.m_states;
    m_state = a_from.m_state;
    m_saved_state = a_from.m_saved_state;
    return *this;
  }
#endif
public:
#ifdef TOOLS_SG_STATES_CUR
  const sg::state& state() const {return *m_state;}
  sg::state& state() {return *m_state;}
  void pop_state() {
    m_state = &(m_states[m_cur_state]);
    m_cur_state--;
  }
  void push_state() {
    if((m_cur_state+1)>=(int)m_states.size()) {
      m_states.resize(m_states.size()+5);
    }
    m_cur_state++;
    m_states[m_cur_state] = *m_state;
  }
#else
  const sg::state& state() const {return m_state;}
  sg::state& state() {return m_state;}
  void pop_state() {
    //if(!m_states.size()) return; //throw.
    m_state = m_states.back();
    m_states.pop_back();
  }
  void push_state() {m_states.push_back(m_state);}
#endif

  void save_state(const sg::state& a_state) {m_saved_state = a_state;}
  const sg::state& saved_state() const {return m_saved_state;}
  sg::state& saved_state() {return m_saved_state;}
protected:
  std::vector<sg::state> m_states;
#ifdef TOOLS_SG_STATES_CUR
  sg::state* m_state;
  int m_cur_state;
#else
  sg::state m_state;
#endif
  sg::state m_saved_state;
};

}}

#endif