/***
    *     Ambient - A music player for the Android platform
    Copyright (C) 2007 Martin Vysny
    
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
    
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
  
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
   */
  
  package sk.baka.ambient.views.gesturelist.keypad;
  
  import java.util.List;
  
  import sk.baka.ambient.R;
  import sk.baka.ambient.views.ContainedPopupWindow;
  import sk.baka.ambient.views.Iconify;
  import sk.baka.ambient.views.gesturelist.GesturesListView;
  import android.text.SpannableStringBuilder;
  import android.view.KeyEvent;
  import android.widget.AdapterView;
  import android.widget.TextView;
  
  /***
   * Handles search using the DPAD only.
   * 
   * @author Martin Vysny
   */
  public final class KeypadDpadSearch extends AbstractKeypadHandler {
  	/***
  	 * Creates new instance
  	 * 
  	 * @param owner
  	 *            the owner.
  	 */
  	public KeypadDpadSearch(final GesturesListView owner) {
  		super(owner);
  		queryWindow = new ContainedPopupWindow(owner,
  				new ContainedPopupWindow.IPlaceable() {
  					public int[] getCoordinates(ContainedPopupWindow popup,
  							CharSequence text, TextView textView) {
  						final int y = owner.getHeight()
  								- (int) textView.getPaint().getTextSize();
  						final int x = (owner.getWidth() - (int) textView
  								.getPaint().measureText(text.toString())) / 2;
  						return new int[] { x, y };
  					}
  				});
  	}
  
  	private char getNext(final char c) {
  		if (c >= 'a' && c <= 'z') {
  			if (c == 'z') {
  				return '0';
  			} else {
  				return (char) (c + 1);
  			}
  		}
  		if (c >= '0' && c <= '9') {
  			if (c == '9') {
  				return 'a';
  			} else {
  				return (char) (c + 1);
  			}
  		}
  		return 'a';
  	}
  
  	private char getPrev(final char c) {
  		if (c >= 'a' && c <= 'z') {
  			if (c == 'a') {
  				return '9';
  			} else {
  				return (char) (c - 1);
  			}
  		}
  		if (c >= '0' && c <= '9') {
  			if (c == '0') {
  				return 'z';
  			} else {
  				return (char) (c - 1);
  			}
  		}
  		return 'a';
  	}
  
  	private final StringBuilder term = new StringBuilder();
  	/***
  	 * Displays the search query.
  	 */
  	private final ContainedPopupWindow queryWindow;
 	/***
 	 * <code>true</code> if entering the search term, <code>false</code> if
 	 * searching.
 	 */
 	private boolean enteringTerm = true;
 
 	@Override
 	public void start() {
 		owner.setTooltip(R.string.dpadSearch_hint1, this, false);
 		enteringTerm = true;
 		term.delete(0, term.length());
 		term.append('a');
 		update();
 	}
 
 	private void update() {
 		if (enteringTerm) {
 			final SpannableStringBuilder b = new SpannableStringBuilder(term);
 			b.insert(b.length() - 1, "#U#");
 			b.append("#D#");
 			Iconify.iconify(owner.getContext(), b);
 			queryWindow.setText(b);
 			selectFirst(0, 1);
 		} else {
 			queryWindow.setText(term);
 		}
 	}
 
 	@Override
 	public void stop() {
 		term.delete(0, term.length());
 		owner.clearTooltip(this);
 		queryWindow.dismiss();
 	}
 
 	@Override
 	public boolean isActivatedByKey(int keyCode, final KeyEvent event) {
 		return false;
 	}
 
 	@Override
 	public boolean isStarted() {
 		return term.length() > 0;
 	}
 
 	@Override
 	protected boolean onConfirm() {
 		if (enteringTerm) {
 			enteringTerm = false;
 			owner.setTooltip(R.string.dpadSearch_hint2, this, false);
 			update();
 		} else {
 			stop();
 		}
 		return true;
 	}
 
 	@Override
 	protected boolean onDown() {
 		if (enteringTerm) {
 			final int lastChar = term.length() - 1;
 			term.setCharAt(lastChar, getNext(term.charAt(lastChar)));
 			update();
 		} else {
 			selectFirst(owner.getSelectedItemPosition() + 1, 1);
 		}
 		return true;
 	}
 
 	@Override
 	protected boolean onLeft() {
 		if (enteringTerm) {
 			if (term.length() > 1) {
 				term.deleteCharAt(term.length() - 1);
 				update();
 			}
 		}
 		return true;
 	}
 
 	@Override
 	protected boolean onRight() {
 		if (enteringTerm) {
 			term.append('a');
 			update();
 		}
 		return true;
 	}
 
 	@Override
 	protected boolean onUp() {
 		if (enteringTerm) {
 			final int lastChar = term.length() - 1;
 			term.setCharAt(lastChar, getPrev(term.charAt(lastChar)));
 			update();
 		} else {
 			selectFirst(owner.getSelectedItemPosition() - 1, -1);
 		}
 		return true;
 	}
 
 	@Override
 	protected boolean onKey(int keyCode, int count, KeyEvent event) {
 		switch (keyCode) {
 		case KeyEvent.KEYCODE_BACK:
 			if (enteringTerm) {
 				stop();
 			} else {
 				enteringTerm = true;
 				owner.setTooltip(R.string.dpadSearch_hint1, this, false);
 				update();
 			}
 			return true;
 		}
 		return super.onKey(keyCode, count, event);
 	}
 
 	/***
 	 * Finds first item which contains given substring.
 	 * 
 	 * @param startIndex
 	 *            search from this item onwards, including the item.
 	 */
 	private void selectFirst(final int startIndex, final int delta) {
 		final String q = term.toString().toLowerCase();
 		final List<String> strModel = owner.getModel().getModelAsString();
 		final int modelLen = strModel.size();
 		int startFrom = startIndex;
 		if ((startFrom < 0) || (startFrom >= modelLen)) {
 			startFrom = delta > 0 ? 0 : modelLen - 1;
 		}
 		// find such an item in the list view
 		for (int i = startFrom; (i < modelLen) && (i >= 0); i += delta) {
 			if (strModel.get(i).contains(q)) {
 				owner.setSelection(i);
 				return;
 			}
 		}
 		owner.setSelection(AdapterView.INVALID_POSITION);
 	}
 }