/*
    * 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.myfaces.tobago.layout;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  public final class PixelMeasure extends Measure {
  
    private static final Logger LOG = LoggerFactory.getLogger(PixelMeasure.class);
  
    static final Measure[] PIXEL_CACHE;
    static final int PIXEL_CACHE_MAX = 4000;
    
    static {
      PIXEL_CACHE = new Measure[PIXEL_CACHE_MAX + 1];
      for (int i = 0; i < PIXEL_CACHE.length; i++) {
        PIXEL_CACHE[i] = new PixelMeasure(i);
      }
    }
    
    private final int pixel;
  
    private PixelMeasure(int pixel) {
      this.pixel = pixel;
    }
  
    static Measure pixelValueOf(int value) {
      if (value >= 0 && value <= PixelMeasure.PIXEL_CACHE_MAX) {
        return PixelMeasure.PIXEL_CACHE[value];
      }
      return new PixelMeasure(value);
    }
    
    public Measure add(Measure m) {
      if (m == null) {
        return this;
      } else {
        return pixelValueOf(pixel + m.getPixel());
      }
    }
  
    public Measure add(int m) {
      return pixelValueOf(pixel + m);
    }
  
    public Measure multiply(int times) {
      return pixelValueOf(pixel * times);
    }
  
    public Measure divide(int times) {
      return pixelValueOf(pixel / times);
    }
  
    public Measure subtractNotNegative(Measure m) {
      if (m == null) {
        return this;
      } else if (m.getPixel() > pixel) {
        LOG.warn("Not enough space! value=" + pixel);
        return ZERO;
      } else {
        return pixelValueOf(pixel - m.getPixel());
      }
    }
  
    public Measure subtract(Measure m) {
      if (m == null) {
        return this;
      } else {
        return pixelValueOf(pixel - m.getPixel());
      }
    }
  
    public Measure subtract(int m) {
        return pixelValueOf(pixel - m);
    }
  
    public int getPixel() {
      return pixel;
    }
  
    @Override
   public String toString() {
     return serialize();
   }
 
   @Override
   public String serialize() {
     return pixel + "px";
   }
 
   @Override
   public boolean equals(Object o) {
     if (this == o) {
       return true;
     }
     if (o == null || getClass() != o.getClass()) {
       return false;
     }
 
     PixelMeasure that = (PixelMeasure) o;
 
     if (pixel != that.pixel) {
       return false;
     }
 
     return true;
   }
 
   @Override
   public int hashCode() {
     return pixel;
   }
 }