/*
  Copyright 2013--2018 James E. McClure, Virginia Polytechnic & State University
  Copyright Equnior ASA

  This file is part of the Open Porous Media project (OPM).
  OPM is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.
  OPM 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 General Public License for more details.
  You should have received a copy of the GNU General Public License
  along with OPM.  If not, see <http://www.gnu.org/licenses/>.
*/
extern "C" void ScaLBL_D3Q19_AAeven_BGK(double *dist, int start, int finish,
                                        int Np, double rlx, double Fx,
                                        double Fy, double Fz) {
    // conserved momemnts
    double rho, ux, uy, uz, uu;
    // non-conserved moments
    double f0, f1, f2, f3, f4, f5, f6, f7, f8, f9, f10, f11, f12, f13, f14, f15,
        f16, f17, f18;

    for (int n = start; n < finish; n++) {
        // q=0
        f0 = dist[n];
        f1 = dist[2 * Np + n];
        f2 = dist[1 * Np + n];
        f3 = dist[4 * Np + n];
        f4 = dist[3 * Np + n];
        f5 = dist[6 * Np + n];
        f6 = dist[5 * Np + n];
        f7 = dist[8 * Np + n];
        f8 = dist[7 * Np + n];
        f9 = dist[10 * Np + n];
        f10 = dist[9 * Np + n];
        f11 = dist[12 * Np + n];
        f12 = dist[11 * Np + n];
        f13 = dist[14 * Np + n];
        f14 = dist[13 * Np + n];
        f15 = dist[16 * Np + n];
        f16 = dist[15 * Np + n];
        f17 = dist[18 * Np + n];
        f18 = dist[17 * Np + n];

        rho = f0 + f2 + f1 + f4 + f3 + f6 + f5 + f8 + f7 + f10 + f9 + f12 +
              f11 + f14 + f13 + f16 + f15 + f18 + f17;
        ux = f1 - f2 + f7 - f8 + f9 - f10 + f11 - f12 + f13 - f14;
        uy = f3 - f4 + f7 - f8 - f9 + f10 + f15 - f16 + f17 - f18;
        uz = f5 - f6 + f11 - f12 - f13 + f14 + f15 - f16 - f17 + f18;
        uu = 1.5 * (ux * ux + uy * uy + uz * uz);

        // q=0
        dist[n] = f0 * (1.0 - rlx) + rlx * 0.3333333333333333 * (1.0 - uu);

        // q = 1
        dist[1 * Np + n] =
            f1 * (1.0 - rlx) +
            rlx * 0.05555555555555555 * (rho + 3.0 * ux + 4.5 * ux * ux - uu) +
            0.16666666 * Fx;

        // q=2
        dist[2 * Np + n] =
            f2 * (1.0 - rlx) +
            rlx * 0.05555555555555555 * (rho - 3.0 * ux + 4.5 * ux * ux - uu) -
            0.16666666 * Fx;

        // q = 3
        dist[3 * Np + n] =
            f3 * (1.0 - rlx) +
            rlx * 0.05555555555555555 * (rho + 3.0 * uy + 4.5 * uy * uy - uu) +
            0.16666666 * Fy;

        // q = 4
        dist[4 * Np + n] =
            f4 * (1.0 - rlx) +
            rlx * 0.05555555555555555 * (rho - 3.0 * uy + 4.5 * uy * uy - uu) -
            0.16666666 * Fy;

        // q = 5
        dist[5 * Np + n] =
            f5 * (1.0 - rlx) +
            rlx * 0.05555555555555555 * (rho + 3.0 * uz + 4.5 * uz * uz - uu) +
            0.16666666 * Fz;

        // q = 6
        dist[6 * Np + n] =
            f6 * (1.0 - rlx) +
            rlx * 0.05555555555555555 * (rho - 3.0 * uz + 4.5 * uz * uz - uu) -
            0.16666666 * Fz;

        // q = 7
        dist[7 * Np + n] =
            f7 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho + 3.0 * (ux + uy) + 4.5 * (ux + uy) * (ux + uy) - uu) +
            0.08333333333 * (Fx + Fy);

        // q = 8
        dist[8 * Np + n] =
            f8 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho - 3.0 * (ux + uy) + 4.5 * (ux + uy) * (ux + uy) - uu) -
            0.08333333333 * (Fx + Fy);

        // q = 9
        dist[9 * Np + n] =
            f9 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho + 3.0 * (ux - uy) + 4.5 * (ux - uy) * (ux - uy) - uu) +
            0.08333333333 * (Fx - Fy);

        // q = 10
        dist[10 * Np + n] =
            f10 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho - 3.0 * (ux - uy) + 4.5 * (ux - uy) * (ux - uy) - uu) -
            0.08333333333 * (Fx - Fy);

        // q = 11
        dist[11 * Np + n] =
            f11 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho + 3.0 * (ux + uz) + 4.5 * (ux + uz) * (ux + uz) - uu) +
            0.08333333333 * (Fx + Fz);

        // q = 12
        dist[12 * Np + n] =
            f12 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho - 3.0 * (ux + uz) + 4.5 * (ux + uz) * (ux + uz) - uu) -
            0.08333333333 * (Fx + Fz);

        // q = 13
        dist[13 * Np + n] =
            f13 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho + 3.0 * (ux - uz) + 4.5 * (ux - uz) * (ux - uz) - uu) +
            0.08333333333 * (Fx - Fz);

        // q= 14
        dist[14 * Np + n] =
            f14 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho - 3.0 * (ux - uz) + 4.5 * (ux - uz) * (ux - uz) - uu) -
            0.08333333333 * (Fx - Fz);

        // q = 15
        dist[15 * Np + n] =
            f15 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho + 3.0 * (uy + uz) + 4.5 * (uy + uz) * (uy + uz) - uu) +
            0.08333333333 * (Fy + Fz);

        // q = 16
        dist[16 * Np + n] =
            f16 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho - 3.0 * (uy + uz) + 4.5 * (uy + uz) * (uy + uz) - uu) -
            0.08333333333 * (Fy + Fz);

        // q = 17
        dist[17 * Np + n] =
            f17 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho + 3.0 * (uy - uz) + 4.5 * (uy - uz) * (uy - uz) - uu) +
            0.08333333333 * (Fy - Fz);

        // q = 18
        dist[18 * Np + n] =
            f18 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho - 3.0 * (uy - uz) + 4.5 * (uy - uz) * (uy - uz) - uu) -
            0.08333333333 * (Fy - Fz);

        //........................................................................
    }
}

extern "C" void ScaLBL_D3Q19_AAodd_BGK(int *neighborList, double *dist,
                                       int start, int finish, int Np,
                                       double rlx, double Fx, double Fy,
                                       double Fz) {
    // conserved momemnts
    double rho, ux, uy, uz, uu;
    // non-conserved moments
    double f0, f1, f2, f3, f4, f5, f6, f7, f8, f9, f10, f11, f12, f13, f14, f15,
        f16, f17, f18;
    int nr1, nr2, nr3, nr4, nr5, nr6, nr7, nr8, nr9, nr10, nr11, nr12, nr13,
        nr14, nr15, nr16, nr17, nr18;

    for (int n = start; n < finish; n++) {

        // q=0
        f0 = dist[n];
        // q=1
        nr1 = neighborList[n]; // neighbor 2 ( > 10Np => odd part of dist)
        f1 = dist[nr1];        // reading the f1 data into register fq

        nr2 = neighborList[n + Np]; // neighbor 1 ( < 10Np => even part of dist)
        f2 = dist[nr2];             // reading the f2 data into register fq

        // q=3
        nr3 = neighborList[n + 2 * Np]; // neighbor 4
        f3 = dist[nr3];

        // q = 4
        nr4 = neighborList[n + 3 * Np]; // neighbor 3
        f4 = dist[nr4];

        // q=5
        nr5 = neighborList[n + 4 * Np];
        f5 = dist[nr5];

        // q = 6
        nr6 = neighborList[n + 5 * Np];
        f6 = dist[nr6];

        // q=7
        nr7 = neighborList[n + 6 * Np];
        f7 = dist[nr7];

        // q = 8
        nr8 = neighborList[n + 7 * Np];
        f8 = dist[nr8];

        // q=9
        nr9 = neighborList[n + 8 * Np];
        f9 = dist[nr9];

        // q = 10
        nr10 = neighborList[n + 9 * Np];
        f10 = dist[nr10];

        // q=11
        nr11 = neighborList[n + 10 * Np];
        f11 = dist[nr11];

        // q=12
        nr12 = neighborList[n + 11 * Np];
        f12 = dist[nr12];

        // q=13
        nr13 = neighborList[n + 12 * Np];
        f13 = dist[nr13];

        // q=14
        nr14 = neighborList[n + 13 * Np];
        f14 = dist[nr14];

        // q=15
        nr15 = neighborList[n + 14 * Np];
        f15 = dist[nr15];

        // q=16
        nr16 = neighborList[n + 15 * Np];
        f16 = dist[nr16];

        // q=17
        //fq = dist[18*Np+n];
        nr17 = neighborList[n + 16 * Np];
        f17 = dist[nr17];

        // q=18
        nr18 = neighborList[n + 17 * Np];
        f18 = dist[nr18];

        rho = f0 + f2 + f1 + f4 + f3 + f6 + f5 + f8 + f7 + f10 + f9 + f12 +
              f11 + f14 + f13 + f16 + f15 + f18 + f17;
        ux = f1 - f2 + f7 - f8 + f9 - f10 + f11 - f12 + f13 - f14;
        uy = f3 - f4 + f7 - f8 - f9 + f10 + f15 - f16 + f17 - f18;
        uz = f5 - f6 + f11 - f12 - f13 + f14 + f15 - f16 - f17 + f18;
        uu = 1.5 * (ux * ux + uy * uy + uz * uz);

        // q=0
        dist[n] = f0 * (1.0 - rlx) + rlx * 0.3333333333333333 * (1.0 - uu);

        // q = 1
        dist[nr2] =
            f1 * (1.0 - rlx) +
            rlx * 0.05555555555555555 * (rho + 3.0 * ux + 4.5 * ux * ux - uu) +
            0.16666666 * Fx;

        // q=2
        dist[nr1] =
            f2 * (1.0 - rlx) +
            rlx * 0.05555555555555555 * (rho - 3.0 * ux + 4.5 * ux * ux - uu) -
            0.16666666 * Fx;

        // q = 3
        dist[nr4] =
            f3 * (1.0 - rlx) +
            rlx * 0.05555555555555555 * (rho + 3.0 * uy + 4.5 * uy * uy - uu) +
            0.16666666 * Fy;

        // q = 4
        dist[nr3] =
            f4 * (1.0 - rlx) +
            rlx * 0.05555555555555555 * (rho - 3.0 * uy + 4.5 * uy * uy - uu) -
            0.16666666 * Fy;

        // q = 5
        dist[nr6] =
            f5 * (1.0 - rlx) +
            rlx * 0.05555555555555555 * (rho + 3.0 * uz + 4.5 * uz * uz - uu) +
            0.16666666 * Fz;

        // q = 6
        dist[nr5] =
            f6 * (1.0 - rlx) +
            rlx * 0.05555555555555555 * (rho - 3.0 * uz + 4.5 * uz * uz - uu) -
            0.16666666 * Fz;

        // q = 7
        dist[nr8] =
            f7 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho + 3.0 * (ux + uy) + 4.5 * (ux + uy) * (ux + uy) - uu) +
            0.08333333333 * (Fx + Fy);

        // q = 8
        dist[nr7] =
            f8 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho - 3.0 * (ux + uy) + 4.5 * (ux + uy) * (ux + uy) - uu) -
            0.08333333333 * (Fx + Fy);

        // q = 9
        dist[nr10] =
            f9 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho + 3.0 * (ux - uy) + 4.5 * (ux - uy) * (ux - uy) - uu) +
            0.08333333333 * (Fx - Fy);

        // q = 10
        dist[nr9] =
            f10 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho - 3.0 * (ux - uy) + 4.5 * (ux - uy) * (ux - uy) - uu) -
            0.08333333333 * (Fx - Fy);

        // q = 11
        dist[nr12] =
            f11 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho + 3.0 * (ux + uz) + 4.5 * (ux + uz) * (ux + uz) - uu) +
            0.08333333333 * (Fx + Fz);

        // q = 12
        dist[nr11] =
            f12 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho - 3.0 * (ux + uz) + 4.5 * (ux + uz) * (ux + uz) - uu) -
            0.08333333333 * (Fx + Fz);

        // q = 13
        dist[nr14] =
            f13 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho + 3.0 * (ux - uz) + 4.5 * (ux - uz) * (ux - uz) - uu) +
            0.08333333333 * (Fx - Fz);

        // q= 14
        dist[nr13] =
            f14 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho - 3.0 * (ux - uz) + 4.5 * (ux - uz) * (ux - uz) - uu) -
            0.08333333333 * (Fx - Fz);

        // q = 15
        dist[nr16] =
            f15 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho + 3.0 * (uy + uz) + 4.5 * (uy + uz) * (uy + uz) - uu) +
            0.08333333333 * (Fy + Fz);

        // q = 16
        dist[nr15] =
            f16 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho - 3.0 * (uy + uz) + 4.5 * (uy + uz) * (uy + uz) - uu) -
            0.08333333333 * (Fy + Fz);

        // q = 17
        dist[nr18] =
            f17 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho + 3.0 * (uy - uz) + 4.5 * (uy - uz) * (uy - uz) - uu) +
            0.08333333333 * (Fy - Fz);

        // q = 18
        dist[nr17] =
            f18 * (1.0 - rlx) +
            rlx * 0.02777777777777778 *
                (rho - 3.0 * (uy - uz) + 4.5 * (uy - uz) * (uy - uz) - uu) -
            0.08333333333 * (Fy - Fz);
    }
}