/*
    * Copyright (C) 2015 Alberto Irurueta Carro (alberto@irurueta.com)
    *
    * Licensed 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 com.irurueta.geometry.estimators;
  
  import com.irurueta.geometry.Line2D;
  import com.irurueta.geometry.NoIntersectionException;
  import com.irurueta.geometry.Point2D;
  import com.irurueta.numerical.robust.PROSACRobustEstimator;
  import com.irurueta.numerical.robust.PROSACRobustEstimatorListener;
  import com.irurueta.numerical.robust.RobustEstimator;
  import com.irurueta.numerical.robust.RobustEstimatorException;
  import com.irurueta.numerical.robust.RobustEstimatorMethod;
  
  import java.util.List;
  
  /**
   * Finds the best 2D point for provided collection of 2D lines using PROSAC
   * algorithm.
   */
  public class PROSACPoint2DRobustEstimator extends Point2DRobustEstimator {
  
      /**
       * Constant defining default threshold to determine whether points are
       * inliers or not.
       * Because typical resolution for points is 1 pixel, then default threshold
       * is defined as 1.
       */
      public static final double DEFAULT_THRESHOLD = 1.0;
  
      /**
       * Minimum value that can be set as threshold.
       * Threshold must be strictly greater than 0.0.
       */
      public static final double MIN_THRESHOLD = 0.0;
  
      /**
       * Indicates that by default inliers will only be computed but not kept.
       */
      public static final boolean DEFAULT_COMPUTE_AND_KEEP_INLIERS = false;
  
      /**
       * Indicates that by default residuals will only be computed but not kept.
       */
      public static final boolean DEFAULT_COMPUTE_AND_KEEP_RESIDUALS = false;
  
      /**
       * Threshold to determine whether lines are inliers or not when testing
       * possible estimation solutions.
       * The threshold refers to the amount of error (i.e. distance) a possible
       * solution has on a sampled line.
       */
      private double threshold;
  
      /**
       * Quality scores corresponding to each provided point.
       * The larger the score value the better the quality of the sample
       */
      private double[] qualityScores;
  
      /**
       * Indicates whether inliers must be computed and kept.
       */
      private boolean computeAndKeepInliers;
  
      /**
       * Indicates whether residuals must be computed and kept.
       */
      private boolean computeAndKeepResiduals;
  
      /**
       * Constructor.
       */
      public PROSACPoint2DRobustEstimator() {
          super();
          threshold = DEFAULT_THRESHOLD;
          computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
          computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
      }
  
      /**
       * Constructor with lines.
       *
       * @param lines 2D lines to estimate a 2D point.
       * @throws IllegalArgumentException if provided list of lines don't have
       *                                  a size greater or equal than MINIMUM_SIZE.
       */
     public PROSACPoint2DRobustEstimator(final List<Line2D> lines) {
         super(lines);
         threshold = DEFAULT_THRESHOLD;
         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
     }
 
     /**
      * Constructor.
      *
      * @param listener listener to be notified of events such as when estimation
      *                 starts, ends or its progress significantly changes.
      */
     public PROSACPoint2DRobustEstimator(final Point2DRobustEstimatorListener listener) {
         super(listener);
         threshold = DEFAULT_THRESHOLD;
         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
     }
 
 
     /**
      * Constructor.
      *
      * @param listener listener to be notified of events such as when estimation
      *                 starts, ends or its progress significantly changes.
      * @param lines    2D lines to estimate a 2D point.
      * @throws IllegalArgumentException if provided list of lines don't have
      *                                  a size greater or equal than MINIMUM_SIZE.
      */
     public PROSACPoint2DRobustEstimator(final Point2DRobustEstimatorListener listener, final List<Line2D> lines) {
         super(listener, lines);
         threshold = DEFAULT_THRESHOLD;
         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
     }
 
     /**
      * Constructor.
      *
      * @param qualityScores quality scores corresponding to each provided line.
      * @throws IllegalArgumentException if provided quality scores length is
      *                                  smaller than MINIMUM_SIZE (i.e. 2 lines).
      */
     public PROSACPoint2DRobustEstimator(final double[] qualityScores) {
         super();
         threshold = DEFAULT_THRESHOLD;
         internalSetQualityScores(qualityScores);
         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
     }
 
     /**
      * Constructor with lines.
      *
      * @param lines         2D lines to estimate a 2D point.
      * @param qualityScores quality scores corresponding to each provided line.
      * @throws IllegalArgumentException if provided list of lines don't have
      *                                  the same size as the list of provided quality scores, or it their size
      *                                  is not greater or equal than MINIMUM_SIZE.
      */
     public PROSACPoint2DRobustEstimator(final List<Line2D> lines, final double[] qualityScores) {
         super(lines);
 
         if (qualityScores.length != lines.size()) {
             throw new IllegalArgumentException();
         }
 
         threshold = DEFAULT_THRESHOLD;
         internalSetQualityScores(qualityScores);
         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
     }
 
     /**
      * Constructor.
      *
      * @param listener      listener to be notified of events such as when estimation
      *                      starts, ends or its progress significantly changes.
      * @param qualityScores quality scores corresponding to each provided line.
      * @throws IllegalArgumentException if provided quality scores length is
      *                                  smaller than MINIMUM_SIZE (i.e. 2 lines).
      */
     public PROSACPoint2DRobustEstimator(final Point2DRobustEstimatorListener listener, final double[] qualityScores) {
         super(listener);
         threshold = DEFAULT_THRESHOLD;
         internalSetQualityScores(qualityScores);
         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
     }
 
 
     /**
      * Constructor.
      *
      * @param listener      listener to be notified of events such as when estimation
      *                      starts, ends or its progress significantly changes.
      * @param lines         2D lines to estimate a 2D point.
      * @param qualityScores quality scores corresponding to each provided line.
      * @throws IllegalArgumentException if provided list of lines don't have
      *                                  the same size as the list of provided quality scores, or it their size
      *                                  is not greater or equal than MINIMUM_SIZE.
      */
     public PROSACPoint2DRobustEstimator(
             final Point2DRobustEstimatorListener listener, final List<Line2D> lines, final double[] qualityScores) {
         super(listener, lines);
 
         if (qualityScores.length != lines.size()) {
             throw new IllegalArgumentException();
         }
 
         threshold = DEFAULT_THRESHOLD;
         internalSetQualityScores(qualityScores);
         computeAndKeepInliers = DEFAULT_COMPUTE_AND_KEEP_INLIERS;
         computeAndKeepResiduals = DEFAULT_COMPUTE_AND_KEEP_RESIDUALS;
     }
 
     /**
      * Returns threshold to determine whether lines are inliers or not when
      * testing possible estimation solutions.
      * The threshold refers to the amount of error a possible solution has on a
      * given line.
      *
      * @return threshold to determine whether lines are inliers or not when
      * testing possible estimation solutions.
      */
     public double getThreshold() {
         return threshold;
     }
 
     /**
      * Sets threshold to determine whether lines are inliers or not when
      * testing possible estimation solutions.
      * The threshold refers to the amount of error a possible solution has on
      * a given line.
      *
      * @param threshold threshold to be set.
      * @throws IllegalArgumentException if provided value is equal or less than
      *                                  zero.
      * @throws LockedException          if robust estimator is locked because an
      *                                  estimation is already in progress.
      */
     public void setThreshold(final double threshold) throws LockedException {
         if (isLocked()) {
             throw new LockedException();
         }
         if (threshold <= MIN_THRESHOLD) {
             throw new IllegalArgumentException();
         }
         this.threshold = threshold;
     }
 
     /**
      * Returns quality scores corresponding to each provided line.
      * The larger the score value the better the quality of the sampled line.
      *
      * @return quality scores corresponding to each line.
      */
     @Override
     public double[] getQualityScores() {
         return qualityScores;
     }
 
     /**
      * Sets quality scores corresponding to each provided line.
      * The larger the score value the better the quality of the sampled line.
      *
      * @param qualityScores quality scores corresponding to each line.
      * @throws LockedException          if robust estimator is locked because an
      *                                  estimation is already in progress.
      * @throws IllegalArgumentException if provided quality scores length is
      *                                  smaller than MINIMUM_SIZE (i.e. 2 samples).
      */
     @Override
     public void setQualityScores(final double[] qualityScores) throws LockedException {
         if (isLocked()) {
             throw new LockedException();
         }
         internalSetQualityScores(qualityScores);
     }
 
     /**
      * Indicates if estimator is ready to start the 2D point estimation.
      * This is true when input data (i.e. 2D lines and quality scores) are
      * provided and a minimum of MINIMUM_SIZE points are available.
      *
      * @return true if estimator is ready, false otherwise.
      */
     @Override
     public boolean isReady() {
         return super.isReady() && qualityScores != null && qualityScores.length == lines.size();
     }
 
     /**
      * Indicates whether inliers must be computed and kept.
      *
      * @return true if inliers must be computed and kept, false if inliers
      * only need to be computed but not kept.
      */
     public boolean isComputeAndKeepInliersEnabled() {
         return computeAndKeepInliers;
     }
 
     /**
      * Specifies whether inliers must be computed and kept.
      *
      * @param computeAndKeepInliers true if inliers must be computed and kept,
      *                              false if inliers only need to be computed but not kept.
      * @throws LockedException if estimator is locked.
      */
     public void setComputeAndKeepInliersEnabled(final boolean computeAndKeepInliers) throws LockedException {
         if (isLocked()) {
             throw new LockedException();
         }
         this.computeAndKeepInliers = computeAndKeepInliers;
     }
 
     /**
      * Indicates whether residuals must be computed and kept.
      *
      * @return true if residuals must be computed and kept, false if residuals
      * only need to be computed but not kept.
      */
     public boolean isComputeAndKeepResidualsEnabled() {
         return computeAndKeepResiduals;
     }
 
     /**
      * Specifies whether residuals must be computed and kept.
      *
      * @param computeAndKeepResiduals true if residuals must be computed and
      *                                kept, false if residuals only need to be computed but not kept.
      * @throws LockedException if estimator is locked.
      */
     public void setComputeAndKeepResidualsEnabled(final boolean computeAndKeepResiduals) throws LockedException {
         if (isLocked()) {
             throw new LockedException();
         }
         this.computeAndKeepResiduals = computeAndKeepResiduals;
     }
 
     /**
      * Estimates a 2D point using a robust estimator and the best set of 2D
      * lines that intersect into the estimated 2D point.
      *
      * @return a 2D point.
      * @throws LockedException          if robust estimator is locked because an
      *                                  estimation is already in progress.
      * @throws NotReadyException        if provided input data is not enough to start
      *                                  the estimation.
      * @throws RobustEstimatorException if estimation fails for any reason
      *                                  (i.e. numerical instability, no solution available, etc).
      */
     @SuppressWarnings("DuplicatedCode")
     @Override
     public Point2D estimate() throws LockedException, NotReadyException, RobustEstimatorException {
         if (isLocked()) {
             throw new LockedException();
         }
         if (!isReady()) {
             throw new NotReadyException();
         }
 
         final var innerEstimator = new PROSACRobustEstimator<>(new PROSACRobustEstimatorListener<Point2D>() {
 
             @Override
             public double getThreshold() {
                 return threshold;
             }
 
             @Override
             public int getTotalSamples() {
                 return lines.size();
             }
 
             @Override
             public int getSubsetSize() {
                 return Point2DRobustEstimator.MINIMUM_SIZE;
             }
 
             @Override
             public void estimatePreliminarSolutions(final int[] samplesIndices, final List<Point2D> solutions) {
                 final var line1 = lines.get(samplesIndices[0]);
                 final var line2 = lines.get(samplesIndices[1]);
 
                 try {
                     final var point = line1.getIntersection(line2);
                     solutions.add(point);
                 } catch (final NoIntersectionException e) {
                     // if points are coincident, no solution is added
                 }
             }
 
             @Override
             public double computeResidual(final Point2D currentEstimation, final int i) {
                 return residual(currentEstimation, lines.get(i));
             }
 
             @Override
             public boolean isReady() {
                 return PROSACPoint2DRobustEstimator.this.isReady();
             }
 
             @Override
             public void onEstimateStart(final RobustEstimator<Point2D> estimator) {
                 if (listener != null) {
                     listener.onEstimateStart(PROSACPoint2DRobustEstimator.this);
                 }
             }
 
             @Override
             public void onEstimateEnd(final RobustEstimator<Point2D> estimator) {
                 if (listener != null) {
                     listener.onEstimateEnd(PROSACPoint2DRobustEstimator.this);
                 }
             }
 
             @Override
             public void onEstimateNextIteration(final RobustEstimator<Point2D> estimator, final int iteration) {
                 if (listener != null) {
                     listener.onEstimateNextIteration(PROSACPoint2DRobustEstimator.this, iteration);
                 }
             }
 
             @Override
             public void onEstimateProgressChange(final RobustEstimator<Point2D> estimator, final float progress) {
                 if (listener != null) {
                     listener.onEstimateProgressChange(PROSACPoint2DRobustEstimator.this, progress);
                 }
             }
 
             @Override
             public double[] getQualityScores() {
                 return qualityScores;
             }
         });
 
         try {
             locked = true;
             inliersData = null;
             innerEstimator.setComputeAndKeepInliersEnabled(computeAndKeepInliers || refineResult);
             innerEstimator.setComputeAndKeepResidualsEnabled(computeAndKeepResiduals || refineResult);
             innerEstimator.setConfidence(confidence);
             innerEstimator.setMaxIterations(maxIterations);
             innerEstimator.setProgressDelta(progressDelta);
             final var result = innerEstimator.estimate();
             inliersData = innerEstimator.getInliersData();
             return attemptRefine(result);
         } catch (final com.irurueta.numerical.LockedException e) {
             throw new LockedException(e);
         } catch (final com.irurueta.numerical.NotReadyException e) {
             throw new NotReadyException(e);
         } finally {
             locked = false;
         }
     }
 
     /**
      * Returns method being used for robust estimation.
      *
      * @return method being used for robust estimation.
      */
     @Override
     public RobustEstimatorMethod getMethod() {
         return RobustEstimatorMethod.PROSAC;
     }
 
     /**
      * Gets standard deviation used for Levenberg-Marquardt fitting during
      * refinement.
      * Returned value gives an indication of how much variance each residual
      * has.
      * Typically, this value is related to the threshold used on each robust
      * estimation, since residuals of found inliers are within the range of
      * such threshold.
      *
      * @return standard deviation used for refinement.
      */
     @Override
     protected double getRefinementStandardDeviation() {
         return threshold;
     }
 
     /**
      * Sets quality scores corresponding to each provided line.
      * This method is used internally and does not check whether instance is
      * locked or not.
      *
      * @param qualityScores quality scores to be set.
      * @throws IllegalArgumentException if provided quality scores length is
      *                                  smaller than MINIMUM_SIZE.
      */
     private void internalSetQualityScores(final double[] qualityScores) {
         if (qualityScores.length < MINIMUM_SIZE) {
             throw new IllegalArgumentException();
         }
 
         this.qualityScores = qualityScores;
     }
 }