/**
 * @file v3math.cpp
 * @brief LLVector3 class implementation.
 *
 * $LicenseInfo:firstyear=2000&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#include "linden_common.h"

#include "v3math.h"

#include "v2math.h"
#include "v4math.h"
#include "m4math.h"
#include "m3math.h"
#include "llquaternion.h"
#include "llquantize.h"
#include "v3dmath.h"

// LLVector3
// WARNING: Don't use these for global const definitions!
// For example:
//      const LLQuaternion(0.5f * F_PI, LLVector3::zero);
// at the top of a *.cpp file might not give you what you think.
const LLVector3 LLVector3::zero(0,0,0);
const LLVector3 LLVector3::x_axis(1.f, 0, 0);
const LLVector3 LLVector3::y_axis(0, 1.f, 0);
const LLVector3 LLVector3::z_axis(0, 0, 1.f);
const LLVector3 LLVector3::x_axis_neg(-1.f, 0, 0);
const LLVector3 LLVector3::y_axis_neg(0, -1.f, 0);
const LLVector3 LLVector3::z_axis_neg(0, 0, -1.f);
const LLVector3 LLVector3::all_one(1.f,1.f,1.f);


// Clamps each values to range (min,max).
// Returns true if data changed.
bool LLVector3::clamp(F32 min, F32 max)
{
    bool ret{ false };

    if (mV[VX] < min) { mV[VX] = min; ret = true; }
    if (mV[VY] < min) { mV[VY] = min; ret = true; }
    if (mV[VZ] < min) { mV[VZ] = min; ret = true; }

    if (mV[VX] > max) { mV[VX] = max; ret = true; }
    if (mV[VY] > max) { mV[VY] = max; ret = true; }
    if (mV[VZ] > max) { mV[VZ] = max; ret = true; }

    return ret;
}

// Clamps length to an upper limit.
// Returns true if the data changed
bool LLVector3::clampLength( F32 length_limit )
{
    bool changed{ false };

    F32 len = length();
    if (llfinite(len))
    {
        if ( len > length_limit)
        {
            normalize();
            if (length_limit < 0.f)
            {
                length_limit = 0.f;
            }
            mV[VX] *= length_limit;
            mV[VY] *= length_limit;
            mV[VZ] *= length_limit;
            changed = true;
        }
    }
    else
    {   // this vector may still be salvagable
        F32 max_abs_component = 0.f;
        for (S32 i = 0; i < 3; ++i)
        {
            F32 abs_component = fabs(mV[i]);
            if (llfinite(abs_component))
            {
                if (abs_component > max_abs_component)
                {
                    max_abs_component = abs_component;
                }
            }
            else
            {
                // no it can't be salvaged --> clear it
                clear();
                changed = true;
                break;
            }
        }
        if (!changed)
        {
            // yes it can be salvaged -->
            // bring the components down before we normalize
            mV[VX] /= max_abs_component;
            mV[VY] /= max_abs_component;
            mV[VZ] /= max_abs_component;
            normalize();

            if (length_limit < 0.f)
            {
                length_limit = 0.f;
            }
            mV[VX] *= length_limit;
            mV[VY] *= length_limit;
            mV[VZ] *= length_limit;
        }
    }

    return changed;
}

bool LLVector3::clamp(const LLVector3& min_vec, const LLVector3& max_vec)
{
    bool ret{ false };

    if (mV[VX] < min_vec[0]) { mV[VX] = min_vec[0]; ret = true; }
    if (mV[VY] < min_vec[1]) { mV[VY] = min_vec[1]; ret = true; }
    if (mV[VZ] < min_vec[2]) { mV[VZ] = min_vec[2]; ret = true; }

    if (mV[VX] > max_vec[0]) { mV[VX] = max_vec[0]; ret = true; }
    if (mV[VY] > max_vec[1]) { mV[VY] = max_vec[1]; ret = true; }
    if (mV[VZ] > max_vec[2]) { mV[VZ] = max_vec[2]; ret = true; }

    return ret;
}


// Sets all values to absolute value of their original values
// Returns true if data changed
bool LLVector3::abs()
{
    bool ret{ false };

    if (mV[VX] < 0.f) { mV[VX] = -mV[VX]; ret = true; }
    if (mV[VY] < 0.f) { mV[VY] = -mV[VY]; ret = true; }
    if (mV[VZ] < 0.f) { mV[VZ] = -mV[VZ]; ret = true; }

    return ret;
}

// Quatizations
void    LLVector3::quantize16(F32 lowerxy, F32 upperxy, F32 lowerz, F32 upperz)
{
    F32 x = mV[VX];
    F32 y = mV[VY];
    F32 z = mV[VZ];

    x = U16_to_F32(F32_to_U16(x, lowerxy, upperxy), lowerxy, upperxy);
    y = U16_to_F32(F32_to_U16(y, lowerxy, upperxy), lowerxy, upperxy);
    z = U16_to_F32(F32_to_U16(z, lowerz,  upperz),  lowerz,  upperz);

    mV[VX] = x;
    mV[VY] = y;
    mV[VZ] = z;
}

void    LLVector3::quantize8(F32 lowerxy, F32 upperxy, F32 lowerz, F32 upperz)
{
    mV[VX] = U8_to_F32(F32_to_U8(mV[VX], lowerxy, upperxy), lowerxy, upperxy);;
    mV[VY] = U8_to_F32(F32_to_U8(mV[VY], lowerxy, upperxy), lowerxy, upperxy);
    mV[VZ] = U8_to_F32(F32_to_U8(mV[VZ], lowerz, upperz), lowerz, upperz);
}


void    LLVector3::snap(S32 sig_digits)
{
    mV[VX] = snap_to_sig_figs(mV[VX], sig_digits);
    mV[VY] = snap_to_sig_figs(mV[VY], sig_digits);
    mV[VZ] = snap_to_sig_figs(mV[VZ], sig_digits);
}

const LLVector3&    LLVector3::rotVec(const LLMatrix3& mat)
{
    *this = *this * mat;
    return *this;
}

const LLVector3&    LLVector3::rotVec(const LLQuaternion& q)
{
    *this = *this * q;
    return *this;
}

const LLVector3& LLVector3::transVec(const LLMatrix4& mat)
{
    setVec(
            mV[VX] * mat.mMatrix[VX][VX] +
            mV[VY] * mat.mMatrix[VX][VY] +
            mV[VZ] * mat.mMatrix[VX][VZ] +
            mat.mMatrix[VX][VW],

            mV[VX] * mat.mMatrix[VY][VX] +
            mV[VY] * mat.mMatrix[VY][VY] +
            mV[VZ] * mat.mMatrix[VY][VZ] +
            mat.mMatrix[VY][VW],

            mV[VX] * mat.mMatrix[VZ][VX] +
            mV[VY] * mat.mMatrix[VZ][VY] +
            mV[VZ] * mat.mMatrix[VZ][VZ] +
            mat.mMatrix[VZ][VW]);

    return *this;
}


const LLVector3&    LLVector3::rotVec(F32 angle, const LLVector3& vec)
{
    if ( !vec.isExactlyZero() && angle )
    {
        *this = *this * LLQuaternion(angle, vec);
    }
    return *this;
}

const LLVector3&    LLVector3::rotVec(F32 angle, F32 x, F32 y, F32 z)
{
    LLVector3 vec(x, y, z);
    if ( !vec.isExactlyZero() && angle )
    {
        *this = *this * LLQuaternion(angle, vec);
    }
    return *this;
}

const LLVector3&    LLVector3::scaleVec(const LLVector3& vec)
{
    mV[VX] *= vec.mV[VX];
    mV[VY] *= vec.mV[VY];
    mV[VZ] *= vec.mV[VZ];

    return *this;
}

LLVector3           LLVector3::scaledVec(const LLVector3& vec) const
{
    LLVector3 ret = LLVector3(*this);
    ret.scaleVec(vec);
    return ret;
}

const LLVector3&    LLVector3::set(const LLVector3d& vec)
{
    mV[VX] = (F32)vec.mdV[VX];
    mV[VY] = (F32)vec.mdV[VY];
    mV[VZ] = (F32)vec.mdV[VZ];
    return (*this);
}

const LLVector3&    LLVector3::set(const LLVector4& vec)
{
    mV[VX] = vec.mV[VX];
    mV[VY] = vec.mV[VY];
    mV[VZ] = vec.mV[VZ];
    return (*this);
}

const LLVector3&    LLVector3::setVec(const LLVector3d& vec)
{
    mV[VX] = (F32)vec.mdV[0];
    mV[VY] = (F32)vec.mdV[1];
    mV[VZ] = (F32)vec.mdV[2];
    return (*this);
}

const LLVector3&    LLVector3::setVec(const LLVector4& vec)
{
    mV[VX] = vec.mV[VX];
    mV[VY] = vec.mV[VY];
    mV[VZ] = vec.mV[VZ];
    return (*this);
}

LLVector3::LLVector3(const LLVector2 &vec)
{
    mV[VX] = (F32)vec.mV[VX];
    mV[VY] = (F32)vec.mV[VY];
    mV[VZ] = 0;
}

LLVector3::LLVector3(const LLVector3d& vec)
{
    mV[VX] = (F32)vec.mdV[VX];
    mV[VY] = (F32)vec.mdV[VY];
    mV[VZ] = (F32)vec.mdV[VZ];
}

LLVector3::LLVector3(const LLVector4& vec)
{
    mV[VX] = (F32)vec.mV[VX];
    mV[VY] = (F32)vec.mV[VY];
    mV[VZ] = (F32)vec.mV[VZ];
}

LLVector3::LLVector3(const LLVector4a& vec)
    : LLVector3(vec.getF32ptr())
{

}

LLVector3::LLVector3(const LLSD& sd)
{
    setValue(sd);
}

LLSD LLVector3::getValue() const
{
    LLSD ret;
    ret[0] = mV[VX];
    ret[1] = mV[VY];
    ret[2] = mV[VZ];
    return ret;
}

void LLVector3::setValue(const LLSD& sd)
{
    mV[VX] = (F32) sd[0].asReal();
    mV[VY] = (F32) sd[1].asReal();
    mV[VZ] = (F32) sd[2].asReal();
}

const LLVector3& operator*=(LLVector3& a, const LLQuaternion& rot)
{
    const F32 rw = - rot.mQ[VX] * a.mV[VX] - rot.mQ[VY] * a.mV[VY] - rot.mQ[VZ] * a.mV[VZ];
    const F32 rx =   rot.mQ[VW] * a.mV[VX] + rot.mQ[VY] * a.mV[VZ] - rot.mQ[VZ] * a.mV[VY];
    const F32 ry =   rot.mQ[VW] * a.mV[VY] + rot.mQ[VZ] * a.mV[VX] - rot.mQ[VX] * a.mV[VZ];
    const F32 rz =   rot.mQ[VW] * a.mV[VZ] + rot.mQ[VX] * a.mV[VY] - rot.mQ[VY] * a.mV[VX];

    a.mV[VX] = - rw * rot.mQ[VX] +  rx * rot.mQ[VW] - ry * rot.mQ[VZ] + rz * rot.mQ[VY];
    a.mV[VY] = - rw * rot.mQ[VY] +  ry * rot.mQ[VW] - rz * rot.mQ[VX] + rx * rot.mQ[VZ];
    a.mV[VZ] = - rw * rot.mQ[VZ] +  rz * rot.mQ[VW] - rx * rot.mQ[VY] + ry * rot.mQ[VX];

    return a;
}

// static
bool LLVector3::parseVector3(const std::string& buf, LLVector3* value)
{
    if( buf.empty() || value == nullptr)
    {
        return false;
    }

    LLVector3 v;
    S32 count = sscanf( buf.c_str(), "%f %f %f", v.mV + 0, v.mV + 1, v.mV + 2 );
    if( 3 == count )
    {
        value->setVec( v );
        return true;
    }

    return false;
}

// Displacement from query point to nearest neighbor point on bounding box.
// Returns zero vector for points within or on the box.
LLVector3 point_to_box_offset(LLVector3& pos, const LLVector3* box)
{
    LLVector3 offset;
    for (S32 k=0; k<3; k++)
    {
        offset[k] = 0;
        if (pos[k] < box[0][k])
        {
            offset[k] = pos[k] - box[0][k];
        }
        else if (pos[k] > box[1][k])
        {
            offset[k] = pos[k] - box[1][k];
        }
    }
    return offset;
}

bool box_valid_and_non_zero(const LLVector3* box)
{
    if (!box[0].isFinite() || !box[1].isFinite())
    {
        return false;
    }
    LLVector3 zero_vec;
    zero_vec.clear();
    if ((box[0] != zero_vec) || (box[1] != zero_vec))
    {
        return true;
    }
    return false;
}