// Created by: Kirill GAVRILOV
// Copyright (c) 2013-2014 OPEN CASCADE SAS
//
// This file is part of Open CASCADE Technology software library.
//
// This library is free software; you can redistribute it and/or modify it under
// the terms of the GNU Lesser General Public License version 2.1 as published
// by the Free Software Foundation, with special exception defined in the file
// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
// distribution for complete text of the license and disclaimer of any warranty.
//
// Alternatively, this file may be used under the terms of Open CASCADE
// commercial license or contractual agreement.

#ifndef _NCollection_Vec4_H__
#define _NCollection_Vec4_H__

#include <NCollection_Vec3.hxx>

//! Generic 4-components vector.
//! To be used as RGBA color vector or XYZW 3D-point with special W-component
//! for operations with projection / model view matrices.
//! Use this class for 3D-points carefully because declared W-component may
//! results in incorrect results if used without matrices.
template<typename Element_t>
class NCollection_Vec4
{

public:

  //! Returns the number of components.
  static int Length()
  {
    return 4;
  }

  //! Empty constructor. Construct the zero vector.
  NCollection_Vec4()
  {
    std::memset (this, 0, sizeof(NCollection_Vec4));
  }

  //! Initialize ALL components of vector within specified value.
  explicit NCollection_Vec4 (const Element_t theValue)
  {
    v[0] = v[1] = v[2] = v[3] = theValue;
  }

  //! Per-component constructor.
  explicit NCollection_Vec4 (const Element_t theX,
                             const Element_t theY,
                             const Element_t theZ,
                             const Element_t theW)
  {
    v[0] = theX;
    v[1] = theY;
    v[2] = theZ;
    v[3] = theW;
  }

  //! Constructor from 2-components vector.
  explicit NCollection_Vec4 (const NCollection_Vec2<Element_t>& theVec2)
  {
    v[0] = theVec2[0];
    v[1] = theVec2[1];
    v[2] = v[3] = Element_t (0);
  }

  //! Constructor from 3-components vector.
  explicit NCollection_Vec4(const NCollection_Vec3<Element_t>& theVec3)
  {
    std::memcpy (this, &theVec3, sizeof(NCollection_Vec3<Element_t>));
    v[3] = Element_t (0);
  }

  //! Constructor from 3-components vector + alpha value.
  explicit NCollection_Vec4(const NCollection_Vec3<Element_t>& theVec3,
                            const Element_t                    theAlpha) {
    std::memcpy (this, &theVec3, sizeof(NCollection_Vec3<Element_t>));
    v[3] = theAlpha;
  }

  //! Copy constructor.
  NCollection_Vec4 (const NCollection_Vec4& theVec4)
  {
    std::memcpy (this, &theVec4, sizeof(NCollection_Vec4));
  }

  //! Assignment operator.
  const NCollection_Vec4& operator= (const NCollection_Vec4& theVec4)
  {
    std::memcpy (this, &theVec4, sizeof(NCollection_Vec4));
    return *this;
  }

  //! Alias to 1st component as X coordinate in XYZW.
  Element_t x() const { return v[0]; }

  //! Alias to 1st component as RED channel in RGBA.
  Element_t r() const { return v[0]; }

  //! Alias to 2nd component as Y coordinate in XYZW.
  Element_t y() const { return v[1]; }

  //! Alias to 2nd component as GREEN channel in RGBA.
  Element_t g() const { return v[1]; }

  //! Alias to 3rd component as Z coordinate in XYZW.
  Element_t z() const { return v[2]; }

  //! Alias to 3rd component as BLUE channel in RGBA.
  Element_t b() const { return v[2]; }

  //! Alias to 4th component as W coordinate in XYZW.
  Element_t w() const { return v[3]; }

  //! Alias to 4th component as ALPHA channel in RGBA.
  Element_t a() const { return v[3]; }

  //! @return 2 of XYZW components in specified order as vector in GLSL-style
  NCOLLECTION_VEC_COMPONENTS_2D(x, y)
  NCOLLECTION_VEC_COMPONENTS_2D(x, z)
  NCOLLECTION_VEC_COMPONENTS_2D(x, w)
  NCOLLECTION_VEC_COMPONENTS_2D(y, z)
  NCOLLECTION_VEC_COMPONENTS_2D(y, w)
  NCOLLECTION_VEC_COMPONENTS_2D(z, w)

  //! @return 3 of XYZW components in specified order as vector in GLSL-style
  NCOLLECTION_VEC_COMPONENTS_3D(x, y, z)
  NCOLLECTION_VEC_COMPONENTS_3D(x, y, w)
  NCOLLECTION_VEC_COMPONENTS_3D(x, z, w)
  NCOLLECTION_VEC_COMPONENTS_3D(y, z, w)

  //! @return RGB components as vector
  NCOLLECTION_VEC_COMPONENTS_3D(r, g, b)

  //! Alias to 1st component as X coordinate in XYZW.
  Element_t& x() { return v[0]; }

  //! Alias to 1st component as RED channel in RGBA.
  Element_t& r() { return v[0]; }

  //! Alias to 2nd component as Y coordinate in XYZW.
  Element_t& y() { return v[1]; }

  //! Alias to 2nd component as GREEN channel in RGBA.
  Element_t& g() { return v[1]; } // Green color

  //! Alias to 3rd component as Z coordinate in XYZW.
  Element_t& z() { return v[2]; }

  //! Alias to 3rd component as BLUE channel in RGBA.
  Element_t& b() { return v[2]; }

  //! Alias to 4th component as W coordinate in XYZW.
  Element_t& w() { return v[3]; }

  //! Alias to 4th component as ALPHA channel in RGBA.
  Element_t& a() { return v[3]; }

  //! @return XY-components modifiable vector
  NCollection_Vec2<Element_t>& xy()
  {
    return *((NCollection_Vec2<Element_t>* )&v[0]);
  }

  //! @return YZ-components modifiable vector
  NCollection_Vec2<Element_t>& yz()
  {
    return *((NCollection_Vec2<Element_t>* )&v[1]);
  }

  //! @return YZ-components modifiable vector
  NCollection_Vec2<Element_t>& zw()
  {
    return *((NCollection_Vec2<Element_t>* )&v[2]);
  }

  //! @return XYZ-components modifiable vector
  NCollection_Vec3<Element_t>& xyz()
  {
    return *((NCollection_Vec3<Element_t>* )&v[0]);
  }

  //! @return YZW-components modifiable vector
  NCollection_Vec3<Element_t>& yzw()
  {
    return *((NCollection_Vec3<Element_t>* )&v[1]);
  }

  //! Raw access to the data (for OpenGL exchange).
  const Element_t* GetData()    const { return v; }
        Element_t* ChangeData()       { return v; }
  operator const   Element_t*() const { return v; }
  operator         Element_t*()       { return v; }

  //! Compute per-component summary.
  NCollection_Vec4& operator+= (const NCollection_Vec4& theAdd)
  {
    v[0] += theAdd.v[0];
    v[1] += theAdd.v[1];
    v[2] += theAdd.v[2];
    v[3] += theAdd.v[3];
    return *this;
  }

  //! Compute per-component summary.
  friend NCollection_Vec4 operator+ (const NCollection_Vec4& theLeft,
                                     const NCollection_Vec4& theRight)
  {
    NCollection_Vec4 aSumm = NCollection_Vec4 (theLeft);
    return aSumm += theRight;
  }

  //! Unary -.
  NCollection_Vec4 operator-() const
  {
    return NCollection_Vec4<Element_t> (-x(), -y(), -z(), -w());
  }

  //! Compute per-component subtraction.
  NCollection_Vec4& operator-= (const NCollection_Vec4& theDec)
  {
    v[0] -= theDec.v[0];
    v[1] -= theDec.v[1];
    v[2] -= theDec.v[2];
    v[3] -= theDec.v[3];
    return *this;
  }

  //! Compute per-component subtraction.
  friend NCollection_Vec4 operator- (const NCollection_Vec4& theLeft,
                                     const NCollection_Vec4& theRight)
  {
    NCollection_Vec4 aSumm = NCollection_Vec4<Element_t> (theLeft);
    return aSumm -= theRight;
  }

  //! Compute per-component multiplication.
  NCollection_Vec4& operator*= (const NCollection_Vec4& theRight)
  {
    v[0] *= theRight.v[0];
    v[1] *= theRight.v[1];
    v[2] *= theRight.v[2];
    v[3] *= theRight.v[3];
    return *this;
  }

  //! Compute per-component multiplication.
  friend NCollection_Vec4 operator* (const NCollection_Vec4& theLeft,
                                     const NCollection_Vec4& theRight)
  {
    NCollection_Vec4 aResult = NCollection_Vec4 (theLeft);
    return aResult *= theRight;
  }

  //! Compute per-component multiplication.
  void Multiply (const Element_t theFactor)
  {
    v[0] *= theFactor;
    v[1] *= theFactor;
    v[2] *= theFactor;
    v[3] *= theFactor;
  }

  //! Compute per-component multiplication.
  NCollection_Vec4& operator*=(const Element_t theFactor)
  {
    Multiply (theFactor);
    return *this;
  }

  //! Compute per-component multiplication.
  NCollection_Vec4 operator* (const Element_t theFactor) const
  {
    return Multiplied (theFactor);
  }

  //! Compute per-component multiplication.
  NCollection_Vec4 Multiplied (const Element_t theFactor) const
  {
    NCollection_Vec4 aCopyVec4 (*this);
    aCopyVec4 *= theFactor;
    return aCopyVec4;
  }

  //! Compute component-wise minimum of two vectors.
  NCollection_Vec4 cwiseMin (const NCollection_Vec4& theVec) const
  {
    return NCollection_Vec4 (v[0] < theVec.v[0] ? v[0] : theVec.v[0],
                             v[1] < theVec.v[1] ? v[1] : theVec.v[1],
                             v[2] < theVec.v[2] ? v[2] : theVec.v[2],
                             v[3] < theVec.v[3] ? v[3] : theVec.v[3]);
  }

  //! Compute component-wise maximum of two vectors.
  NCollection_Vec4 cwiseMax (const NCollection_Vec4& theVec) const
  {
    return NCollection_Vec4 (v[0] > theVec.v[0] ? v[0] : theVec.v[0],
                             v[1] > theVec.v[1] ? v[1] : theVec.v[1],
                             v[2] > theVec.v[2] ? v[2] : theVec.v[2],
                             v[3] > theVec.v[3] ? v[3] : theVec.v[3]);
  }

  //! Compute component-wise modulus of the vector.
  NCollection_Vec4 cwiseAbs() const
  {
    return NCollection_Vec4 (std::abs (v[0]),
                             std::abs (v[1]),
                             std::abs (v[2]),
                             std::abs (v[3]));
  }

  //! Compute maximum component of the vector.
  Element_t maxComp() const
  {
    const Element_t aMax1 = v[0] > v[1] ? v[0] : v[1];
    const Element_t aMax2 = v[2] > v[3] ? v[2] : v[3];

    return aMax1 > aMax2 ? aMax1 : aMax2;
  }

  //! Compute minimum component of the vector.
  Element_t minComp() const
  {
    const Element_t aMin1 = v[0] < v[1] ? v[0] : v[1];
    const Element_t aMin2 = v[2] < v[3] ? v[2] : v[3];

    return aMin1 < aMin2 ? aMin1 : aMin2;
  }

  //! Compute per-component division by scale factor.
  NCollection_Vec4& operator/= (const Element_t theInvFactor)
  {
    v[0] /= theInvFactor;
    v[1] /= theInvFactor;
    v[2] /= theInvFactor;
    v[3] /= theInvFactor;
    return *this;
  }

  //! Compute per-component division by scale factor.
  NCollection_Vec4 operator/ (const Element_t theInvFactor)
  {
    NCollection_Vec4 aResult(*this);
    return aResult /= theInvFactor;
  }

private:

  Element_t v[4]; //!< define the vector as array to avoid structure alignment issues

};

//! Optimized concretization for float type.
template<> inline NCollection_Vec4<float>& NCollection_Vec4<float>::operator/= (const float theInvFactor)
{
  Multiply (1.0f / theInvFactor);
  return *this;
}

//! Optimized concretization for double type.
template<> inline NCollection_Vec4<double>& NCollection_Vec4<double>::operator/= (const double theInvFactor)
{
  Multiply (1.0 / theInvFactor);
  return *this;
}

#endif // _NCollection_Vec4_H__
