FilterCursorWrapper

import java.text.Normalizer;

import android.database.Cursor;
import android.database.CursorWrapper;
import android.util.Log;


//by Ricardo derfreitas@gmail.com
//ref: https://gist.github.com/ramzes642/5400792 (the position retrieved is not correct)
//ref: http://stackoverflow.com/a/7343721/689223 (doesn't do string filtering)
//the two code bases were merged to get the best of both worlds
//also added was an option to remove accents from UTF strings
public class FilterCursorWrapper extends CursorWrapper {
	private static final String TAG = FilterCursorWrapper.class.getSimpleName();
	private String filter;
	private int column;
	private int[] filterMap;
	private int mPos = -1;
	private int mCount = 0;

	public FilterCursorWrapper(Cursor cursor,String filter,int column) {
		super(cursor);
		this.filter = deAccent(filter).toLowerCase();
		Log.d(TAG, "filter:"+this.filter);
		this.column = column;
		int count = super.getCount();
		
		if (this.filter != "") {
			this.filterMap = new int[count];
			int filteredCount = 0;
			for (int i=0;i<count;i++) {
				super.moveToPosition(i);
				if (deAccent(this.getString(this.column)).toLowerCase().contains(this.filter)){
					this.filterMap[filteredCount] = i;
					filteredCount++;
				}
			}
			this.mCount = filteredCount;
		} else {
			this.filterMap = new int[count];
			this.mCount = count;
			for (int i=0;i<count;i++) {
				this.filterMap[i] = i;
			}
		}
		
		this.moveToFirst();
	}
	
	
	
	public int getCount() { return this.mCount; }
	
	@Override
	public boolean moveToPosition(int position) {
		Log.d(TAG,"moveToPosition:"+position);
	    // Make sure position isn't past the end of the cursor
	    final int count = getCount();
	    if (position >= count) {
	        mPos = count;
	        return false;
	    }
	    // Make sure position isn't before the beginning of the cursor
	    if (position < 0) {
	        mPos = -1;
	        return false;
	    }
	    final int realPosition = filterMap[position];
	    // When moving to an empty position, just pretend we did it
	    boolean moved = realPosition == -1 ? true : super.moveToPosition(realPosition);
	    if (moved) {
	        mPos = position;
	    } else {
	        mPos = -1;
	    }
	    Log.d(TAG,"end moveToPosition:"+position);
	    return moved;
	}
	@Override
	public final boolean move(int offset) {
	    return moveToPosition(mPos + offset);
	}
	@Override
	public final boolean moveToFirst() {
	    return moveToPosition(0);
	}
	@Override
	public final boolean moveToLast() {
	    return moveToPosition(getCount() - 1);
	}
	@Override
	public final boolean moveToNext() {
	    return moveToPosition(mPos + 1);
	}
	@Override
	public final boolean moveToPrevious() {
	    return moveToPosition(mPos - 1);
	}
	@Override
	public final boolean isFirst() {
	    return mPos == 0 && getCount() != 0;
	}
	@Override
	public final boolean isLast() {
	    int cnt = getCount();
	    return mPos == (cnt - 1) && cnt != 0;
	}
	@Override
	public final boolean isBeforeFirst() {
	    if (getCount() == 0) {
	        return true;
	    }
	    return mPos == -1;
	}
	@Override
	public final boolean isAfterLast() {
	    if (getCount() == 0) {
	        return true;
	    }
	    return mPos == getCount();
	}
	@Override
	public int getPosition() {
	    return mPos;
	}
	
	//added by Ricardo
	//ref: http://stackoverflow.com/a/22612054/689223
	//other: http://stackoverflow.com/questions/8523631/remove-accents-from-string
	//other: http://stackoverflow.com/questions/15190656/easy-way-to-remove-utf-8-accents-from-a-string
	public static String deAccent(String str) {
	    //return StringUtils.stripAccents(str);//this method from apache.commons respects chinese characters, but it's slower than flattenToAscii
	    return flattenToAscii(str);
	}
	
	//ref: http://stackoverflow.com/a/15191508/689223
	//this is the fastest method using the normalizer found yet, the ones using Regex are too slow
	public static String flattenToAscii(String string) {
	    char[] out = new char[string.length()];
	    string = Normalizer.normalize(string, Normalizer.Form.NFD);
	    int j = 0;
	    for (int i = 0, n = string.length(); i < n; ++i) {
	        char c = string.charAt(i);
	        if (c <= '\u007F') out[j++] = c;
	    }
	    return new String(out);
	}
}