package oldapi;

import java.io.*;

import org.apache.hadoop.io.*;

public class TextPair implements WritableComparable<TextPair> {

  private Text first;
  private Text second;
  
  public TextPair() {
    set(new Text(), new Text());
  }
  
  public TextPair(String first, String second) {
    set(new Text(first), new Text(second));
  }
  
  public TextPair(Text first, Text second) {
    set(first, second);
  }
  
  public void set(Text first, Text second) {
    this.first = first;
    this.second = second;
  }
  
  public Text getFirst() {
    return first;
  }

  public Text getSecond() {
    return second;
  }

  @Override
  public void write(DataOutput out) throws IOException {
    first.write(out);
    second.write(out);
  }

  @Override
  public void readFields(DataInput in) throws IOException {
    first.readFields(in);
    second.readFields(in);
  }
  
  @Override
  public int hashCode() {
    return first.hashCode() * 163 + second.hashCode();
  }
  
  @Override
  public boolean equals(Object o) {
    if (o instanceof TextPair) {
      TextPair tp = (TextPair) o;
      return first.equals(tp.first) && second.equals(tp.second);
    }
    return false;
  }

  @Override
  public String toString() {
    return first + "\t" + second;
  }
  
  @Override
  public int compareTo(TextPair tp) {
    int cmp = first.compareTo(tp.first);
    if (cmp != 0) {
      return cmp;
    }
    return second.compareTo(tp.second);
  }

  public static class Comparator extends WritableComparator {
    
    private static final Text.Comparator TEXT_COMPARATOR = new Text.Comparator();
    
    public Comparator() {
      super(TextPair.class);
    }

    @Override
    public int compare(byte[] b1, int s1, int l1,
                       byte[] b2, int s2, int l2) {
      
      try {
        int firstL1 = WritableUtils.decodeVIntSize(b1[s1]) + readVInt(b1, s1);
        int firstL2 = WritableUtils.decodeVIntSize(b2[s2]) + readVInt(b2, s2);
        int cmp = TEXT_COMPARATOR.compare(b1, s1, firstL1, b2, s2, firstL2);
        if (cmp != 0) {
          return cmp;
        }
        return TEXT_COMPARATOR.compare(b1, s1 + firstL1, l1 - firstL1,
                                       b2, s2 + firstL2, l2 - firstL2);
      } catch (IOException e) {
        throw new IllegalArgumentException(e);
      }
    }
  }

  static {
    WritableComparator.define(TextPair.class, new Comparator());
  }

  public static class FirstComparator extends WritableComparator {
    
    private static final Text.Comparator TEXT_COMPARATOR = new Text.Comparator();
    
    public FirstComparator() {
      super(TextPair.class);
    }

    @Override
    public int compare(byte[] b1, int s1, int l1,
                       byte[] b2, int s2, int l2) {
      
      try {
        int firstL1 = WritableUtils.decodeVIntSize(b1[s1]) + readVInt(b1, s1);
        int firstL2 = WritableUtils.decodeVIntSize(b2[s2]) + readVInt(b2, s2);
        return TEXT_COMPARATOR.compare(b1, s1, firstL1, b2, s2, firstL2);
      } catch (IOException e) {
        throw new IllegalArgumentException(e);
      }
    }
    
    @Override
    public int compare(WritableComparable a, WritableComparable b) {
      if (a instanceof TextPair && b instanceof TextPair) {
        return ((TextPair) a).first.compareTo(((TextPair) b).first);
      }
      return super.compare(a, b);
    }
  }
}
