// 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_Vec2_HeaderFile
#define NCollection_Vec2_HeaderFile

#include <cmath> // std::sqrt()

#include <Standard_Dump.hxx>

//! Auxiliary macros to define couple of similar access components as vector methods.
//! @return 2 components by their names in specified order
#define NCOLLECTION_VEC_COMPONENTS_2D(theX, theY)                                                  \
  const NCollection_Vec2<Element_t> theX##theY() const                                             \
  {                                                                                                \
    return NCollection_Vec2<Element_t>(theX(), theY());                                            \
  }                                                                                                \
  const NCollection_Vec2<Element_t> theY##theX() const                                             \
  {                                                                                                \
    return NCollection_Vec2<Element_t>(theY(), theX());                                            \
  }

//! Defines the 2D-vector template.
//! The main target for this class - to handle raw low-level arrays (from/to graphic driver etc.).
template <typename Element_t>
class NCollection_Vec2
{

public:
  //! Returns the number of components.
  static int Length() { return 2; }

  //! Empty constructor. Construct the zero vector.
  NCollection_Vec2() { v[0] = v[1] = Element_t(0); }

  //! Initialize ALL components of vector within specified value.
  explicit NCollection_Vec2(const Element_t theXY) { v[0] = v[1] = theXY; }

  //! Per-component constructor.
  explicit NCollection_Vec2(const Element_t theX, const Element_t theY)
  {
    v[0] = theX;
    v[1] = theY;
  }

  //! Conversion constructor (explicitly converts some 2-component vector with other element type
  //! to a new 2-component vector with the element type Element_t,
  //! whose elements are static_cast'ed corresponding elements of theOtherVec2 vector)
  //! @tparam OtherElement_t the element type of the other 2-component vector theOtherVec2
  //! @param theOtherVec2 the 2-component vector that needs to be converted
  template <typename OtherElement_t>
  explicit NCollection_Vec2(const NCollection_Vec2<OtherElement_t>& theOtherVec2)
  {
    v[0] = static_cast<Element_t>(theOtherVec2[0]);
    v[1] = static_cast<Element_t>(theOtherVec2[1]);
  }

  //! Assign new values to the vector.
  void SetValues(const Element_t theX, const Element_t theY)
  {
    v[0] = theX;
    v[1] = theY;
  }

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

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

  //! @return 2 components by their names in specified order (in GLSL-style)
  NCOLLECTION_VEC_COMPONENTS_2D(x, y)

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

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

  //! Check this vector with another vector for equality (without tolerance!).
  bool IsEqual(const NCollection_Vec2& theOther) const
  {
    return v[0] == theOther.v[0] && v[1] == theOther.v[1];
  }

  //! Check this vector with another vector for equality (without tolerance!).
  bool operator==(const NCollection_Vec2& theOther) const { return IsEqual(theOther); }

  //! Check this vector with another vector for non-equality (without tolerance!).
  bool operator!=(const NCollection_Vec2& theOther) const { return !IsEqual(theOther); }

  //! 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_Vec2& operator+=(const NCollection_Vec2& theAdd)
  {
    v[0] += theAdd.v[0];
    v[1] += theAdd.v[1];
    return *this;
  }

  //! Compute per-component summary.
  friend NCollection_Vec2 operator+(const NCollection_Vec2& theLeft,
                                    const NCollection_Vec2& theRight)
  {
    return NCollection_Vec2(theLeft.v[0] + theRight.v[0], theLeft.v[1] + theRight.v[1]);
  }

  //! Compute per-component subtraction.
  NCollection_Vec2& operator-=(const NCollection_Vec2& theDec)
  {
    v[0] -= theDec.v[0];
    v[1] -= theDec.v[1];
    return *this;
  }

  //! Compute per-component subtraction.
  friend NCollection_Vec2 operator-(const NCollection_Vec2& theLeft,
                                    const NCollection_Vec2& theRight)
  {
    return NCollection_Vec2(theLeft.v[0] - theRight.v[0], theLeft.v[1] - theRight.v[1]);
  }

  //! Unary -.
  NCollection_Vec2 operator-() const { return NCollection_Vec2(-x(), -y()); }

  //! Compute per-component multiplication.
  NCollection_Vec2& operator*=(const NCollection_Vec2& theRight)
  {
    v[0] *= theRight.v[0];
    v[1] *= theRight.v[1];
    return *this;
  }

  //! Compute per-component multiplication.
  friend NCollection_Vec2 operator*(const NCollection_Vec2& theLeft,
                                    const NCollection_Vec2& theRight)
  {
    return NCollection_Vec2(theLeft.v[0] * theRight.v[0], theLeft.v[1] * theRight.v[1]);
  }

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

  //! Compute per-component multiplication by scale factor.
  NCollection_Vec2 Multiplied(const Element_t theFactor) const
  {
    return NCollection_Vec2(v[0] * theFactor, v[1] * theFactor);
  }

  //! Compute component-wise minimum of two vectors.
  NCollection_Vec2 cwiseMin(const NCollection_Vec2& theVec) const
  {
    return NCollection_Vec2(v[0] < theVec.v[0] ? v[0] : theVec.v[0],
                            v[1] < theVec.v[1] ? v[1] : theVec.v[1]);
  }

  //! Compute component-wise maximum of two vectors.
  NCollection_Vec2 cwiseMax(const NCollection_Vec2& theVec) const
  {
    return NCollection_Vec2(v[0] > theVec.v[0] ? v[0] : theVec.v[0],
                            v[1] > theVec.v[1] ? v[1] : theVec.v[1]);
  }

  //! Compute component-wise modulus of the vector.
  NCollection_Vec2 cwiseAbs() const { return NCollection_Vec2(std::abs(v[0]), std::abs(v[1])); }

  //! Compute maximum component of the vector.
  Element_t maxComp() const { return v[0] > v[1] ? v[0] : v[1]; }

  //! Compute minimum component of the vector.
  Element_t minComp() const { return v[0] < v[1] ? v[0] : v[1]; }

  //! Compute per-component multiplication by scale factor.
  NCollection_Vec2& operator*=(const Element_t theFactor)
  {
    Multiply(theFactor);
    return *this;
  }

  //! Compute per-component division by scale factor.
  NCollection_Vec2& operator/=(const Element_t theInvFactor)
  {
    v[0] /= theInvFactor;
    v[1] /= theInvFactor;
    return *this;
  }

  //! Compute per-component division.
  NCollection_Vec2& operator/=(const NCollection_Vec2& theRight)
  {
    v[0] /= theRight.v[0];
    v[1] /= theRight.v[1];
    return *this;
  }

  //! Compute per-component multiplication by scale factor.
  NCollection_Vec2 operator*(const Element_t theFactor) const { return Multiplied(theFactor); }

  //! Compute per-component division by scale factor.
  NCollection_Vec2 operator/(const Element_t theInvFactor) const
  {
    return NCollection_Vec2(v[0] / theInvFactor, v[1] / theInvFactor);
  }

  //! Compute per-component division.
  friend NCollection_Vec2 operator/(const NCollection_Vec2& theLeft,
                                    const NCollection_Vec2& theRight)
  {
    return NCollection_Vec2(theLeft.v[0] / theRight.v[0], theLeft.v[1] / theRight.v[1]);
  }

  //! Computes the dot product.
  Element_t Dot(const NCollection_Vec2& theOther) const
  {
    return x() * theOther.x() + y() * theOther.y();
  }

  //! Computes the vector modulus (magnitude, length).
  Element_t Modulus() const { return std::sqrt(x() * x() + y() * y()); }

  //! Computes the square of vector modulus (magnitude, length).
  //! This method may be used for performance tricks.
  Element_t SquareModulus() const { return x() * x() + y() * y(); }

  //! Construct DX unit vector.
  static NCollection_Vec2 DX() { return NCollection_Vec2(Element_t(1), Element_t(0)); }

  //! Construct DY unit vector.
  static NCollection_Vec2 DY() { return NCollection_Vec2(Element_t(0), Element_t(1)); }

  //! Dumps the content of me into the stream
  void DumpJson(Standard_OStream& theOStream, Standard_Integer theDepth = -1) const
  {
    (void)theDepth;
    OCCT_DUMP_FIELD_VALUES_NUMERICAL(theOStream, "Vec2", 2, v[0], v[1])
  }

private:
  Element_t v[2];
};

#endif // _NCollection_Vec2_H__