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

#ifndef tools_sg_matrix_action
#define tools_sg_matrix_action

#include "win_action"

#include "../lina/mat4f"
#include "states"

namespace tools {
namespace sg {

class matrix_action : public win_action,public states {
  TOOLS_ACTION(matrix_action,tools::sg::matrix_action,win_action)
public:
  matrix_action(std::ostream& a_out,unsigned int a_ww,unsigned int a_wh)
  :parent(a_out,a_ww,a_wh)
  ,states(a_ww,a_wh)
  ,m_cur(0)
  ,m_landscape(true)
  {
    m_projs.resize(5);
    m_models.resize(5);
    reset();
    m_identity.set_identity();
  }
  virtual ~matrix_action(){}
public:
  matrix_action(const matrix_action& a_from)
  :parent(a_from)
  ,states(a_from)
  ,m_projs(a_from.m_projs)
  ,m_models(a_from.m_models)
  ,m_cur(a_from.m_cur)
  ,m_landscape(a_from.m_landscape)
  {
    m_identity.set_identity();
  }
  matrix_action& operator=(const matrix_action& a_from){
    parent::operator=(a_from);
    states::operator=(a_from);
    m_projs = a_from.m_projs;
    m_models = a_from.m_models;
    m_cur = a_from.m_cur;
    m_landscape = a_from.m_landscape;
    return *this;
  }
public:
  void push_matrices() {
    if((m_cur+1)>=(int)m_projs.size()) {
      m_projs.resize(m_projs.size()+5);
      m_models.resize(m_models.size()+5);
    }
    m_cur++;
    m_projs[m_cur].set_matrix(m_projs[m_cur-1]);
    m_models[m_cur].set_matrix(m_models[m_cur-1]);
  }

  //WARNING : in the three below methods, there is no
  //          protection against m_cur<0 being zero here.
  void pop_matrices() {
    m_cur--;
  }
  mat4f& projection_matrix() {return m_projs[m_cur];}
  mat4f& model_matrix() {return m_models[m_cur];}

  bool end() const {return m_cur==0?true:false;}
  int cur() const {return m_cur;}

  bool project_point(float& a_x,float& a_y,float& a_z,float& a_w) {
    a_w = 1;
    model_matrix().mul_4f(a_x,a_y,a_z,a_w);
    projection_matrix().mul_4f(a_x,a_y,a_z,a_w);
    if(a_w==0.0F) return false;
    a_x /= a_w;
    a_y /= a_w;
    a_z /= a_w;
    return true;
  }

  void model_point(float& a_x,float& a_y,float& a_z,float& a_w) {
    a_w = 1;
    model_matrix().mul_4f(a_x,a_y,a_z,a_w);
  }

  // for marker rendering :
  void projected_origin(float& a_x,float& a_y,float& a_z) {
    a_x = 0;
    a_y = 0;
    a_z = 0;
    float w;
    project_point(a_x,a_y,a_z,w); //if render : in [-1,1][-1,1]
  }

protected:
  void reset() {
    m_cur = 0;
    if(m_landscape) {
      m_projs[m_cur].set_identity();
    } else {
      m_projs[m_cur].set_matrix(0,-1,0,0,
                                1, 0,0,0,
                                0, 0,1,0,
                                0, 0,0,1);
    }
    m_models[m_cur].set_identity();
    sg::state& _state = state();
    _state.m_proj = m_projs[m_cur];
    _state.m_model = m_models[m_cur];
  }
protected:
  std::vector<mat4f> m_projs;
  std::vector<mat4f> m_models;
  int m_cur;
  mat4f m_identity;
private:
  bool m_landscape; //false not yet ready.
};

}}

#endif
