/*
 * Hedgewars for Android. An Android port of Hedgewars, a free turn based strategy game
 * Copyright (C) 2012 Simeon Maxein <smaxein@googlemail.com>
 *
 * 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 2
 * 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, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

package org.hedgewars.hedgeroid;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import org.hedgewars.hedgeroid.netplay.MessageLog;

import android.content.Context;
import android.text.method.LinkMovementMethod;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView.LayoutParams;
import android.widget.BaseAdapter;
import android.widget.TextView;

/**
 * Optimization: ListView is smart enough to try re-using the same view for an item
 * with the same ID, but it still calls getView for those items when the list changes.
 * Since lines with a given ID never change in our chatlog, we can avoid the effort
 * of TextView.setText in many cases by checking if the view is already set up for the
 * line with the right ID - but to do that, the view needs to remember the ID it's
 * holding the text for. That's what the LoglineView does. 
 */
class LoglineView extends TextView {
	long chatlogId = -1;
	
	public LoglineView(Context context) {
		super(context);
	}
}

/**
 * For performance reasons, the chatlog is implemented as ListView instead of a
 * single TextView (although I later learned that TextView might also have
 * facilities for efficient appending with limited backlog... oh well, this
 * works). Every chat line is a line in the ListView, and this adapter prepares
 * the textviews from a messagelog in an efficient way.
 */
public class ChatlogAdapter extends BaseAdapter implements MessageLog.Listener {
	long idOffset = 0;
	private List<CharSequence> log = new ArrayList<CharSequence>();
	private Context context;
	
	public ChatlogAdapter(Context context) {
		this.context = context;
	}
	
	public int getCount() {
		return log.size();
	}

	public Object getItem(int position) {
		return log.get(position);
	}

	public long getItemId(int position) {
		return position+idOffset;
	}

	public boolean hasStableIds() {
		return true;
	}

	public void clear() {
		idOffset += log.size();
		log.clear();
		notifyDataSetChanged();
	}
	
	public void lineAdded(CharSequence text) {
		log.add(text);
		notifyDataSetChanged();
	}
	
	public void lineRemoved() {
		log.remove(0);
		idOffset += 1;
		notifyDataSetChanged();
	}
	
	public void setLog(Collection<CharSequence> log) {
		idOffset += log.size();
		this.log = new ArrayList<CharSequence>(log);
		notifyDataSetChanged();
	}
	
	public View getView(int position, View convertView, ViewGroup parent) {
		LoglineView v = (LoglineView)convertView;
		if (v == null) {
			v = new LoglineView(context);
			v.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));
			v.setMovementMethod(LinkMovementMethod.getInstance());
		}
		long id = getItemId(position);
		if(id != v.chatlogId) {
			v.setText(log.get(position));
			v.chatlogId = id;
		}
		return v;
	}
}