/**

 * Back 2 Browser Bytecode Translator

 * Copyright (C) 2012-2015 Jaroslav Tulach <jaroslav.tulach@apidesign.org>

 *

 * This program 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, version 2 of the License.

 *

 * This program 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 this program. Look for COPYING file in the top folder.

 * If not, see http://opensource.org/licenses/GPL-2.0.

 */

package org.apidesign.benchmark.matrixmul;

import java.io.IOException;

import java.util.Arrays;

public class Matrix {

    private final int rank;

    private final float data[][];

    public Matrix(int r) {

        this(r, new float[r][r]);

    }

    private Matrix(int r, float[][] data) {

        this.rank = r;

        this.data = data;

    }

    public void setElement(int i, int j, float value) {

        data[i][j] = value;

    }

    public float getElement(int i, int j) {

        return data[i][j];

    }

    public void generateData() {

        //final Random rand = new Random();

        //final int x = 10;

        for (int i = 0; i < rank; i++) {

            for (int j = 0; j < rank; j++) {

                data[i][j] = 1 / (1 + i + j);

            }

        }

    }

    public Matrix multiply(Matrix m) {

        if (rank != m.rank) {

            throw new IllegalArgumentException("Rank doesn't match");

        }

        final float res[][] = new float[rank][rank];

        for (int i = 0; i < rank; i++) {

            for (int j = 0; j < rank; j++) {

                float ij = 0;

                for (int q = 0; q < rank; q++) {

                    ij += data[i][q] * m.data[q][j];

                }

                res[i][j] = ij;

            }

        }

        return new Matrix(rank, res);

    }

    public void printOn(Appendable s) throws IOException {

        for (int i = 0; i < rank; i++) {

            String sep = "";

            for (int j = 0; j < rank; j++) {

                s.append(sep + data[i][j]);

                sep = " ";

            }

            s.append("\n");

        }

    }

    @Override

    public boolean equals(Object obj) {

        if (obj instanceof Matrix) {

            Matrix snd = (Matrix)obj;

            if (snd.rank != rank) {

                return false;

            }

            for (int i = 0; i < rank; i++) {

                for (int j = 0; j < rank; j++) {

                    if (data[i][j] != snd.data[i][j]) {

                        return false;

                    }

                }

            }

            return true;

        }

        return false;

    }

    @Override

    public int hashCode() {

        int hash = 3;

        hash = 97 * hash + this.rank;

        hash = 97 * hash + Arrays.deepHashCode(this.data);

        return hash;

    }

}