/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.mahout.math.decomposer.lanczos;

import com.google.common.collect.Maps;
import org.apache.mahout.math.DenseMatrix;
import org.apache.mahout.math.Matrix;
import org.apache.mahout.math.Vector;
import org.apache.mahout.math.VectorIterable;

import java.util.Map;

public class LanczosState {

  protected  Matrix diagonalMatrix;
  protected final VectorIterable corpus;
  protected double scaleFactor;
  protected int iterationNumber;
  protected final int desiredRank;
  protected Map<Integer, Vector> basis;
  protected final Map<Integer, Double> singularValues;
  protected Map<Integer, Vector> singularVectors;

  public LanczosState(VectorIterable corpus, int desiredRank, Vector initialVector) {
    this.corpus = corpus;
    this.desiredRank = desiredRank;
    intitializeBasisAndSingularVectors();
    setBasisVector(0, initialVector);
    scaleFactor = 0;
    diagonalMatrix = new DenseMatrix(desiredRank, desiredRank);
    singularValues = Maps.newHashMap();
    iterationNumber = 1;
  }

  protected void intitializeBasisAndSingularVectors() {
    basis = Maps.newHashMap();
    singularVectors = Maps.newHashMap();
  }

  public Matrix getDiagonalMatrix() {
    return diagonalMatrix;
  }

  public int getIterationNumber() {
    return iterationNumber;
  }

  public double getScaleFactor() {
    return scaleFactor;
  }

  public VectorIterable getCorpus() {
    return corpus;
  }

  public Vector getRightSingularVector(int i) {
    return singularVectors.get(i);
  }

  public Double getSingularValue(int i) {
    return singularValues.get(i);
  }

  public Vector getBasisVector(int i) {
    return basis.get(i);
  }

  public int getBasisSize(){
    return basis.size();
  }

  public void setBasisVector(int i, Vector basisVector) {
    basis.put(i, basisVector);
  }

  public void setScaleFactor(double scale) {
    scaleFactor = scale;
  }

  public void setIterationNumber(int i) {
    iterationNumber = i;
  }

  public void setRightSingularVector(int i, Vector vector) {
    singularVectors.put(i, vector);
  }

  public void setSingularValue(int i, double value) {
    singularValues.put(i, value);
  }
}