/*
 * 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 com.l2jserver.gameserver.model;

import com.l2jserver.Config;
import com.l2jserver.util.Rnd;

import javolution.util.FastList;

/**
 *
 * @author  Fulminus
 */
public class L2DropCategory
{
	private FastList<L2DropData> _drops;
	private int _categoryChance; // a sum of chances for calculating if an item will be dropped from this category
	private int _categoryBalancedChance; // sum for balancing drop selection inside categories in high rate servers
	private int _categoryType;

	public L2DropCategory(int categoryType)
	{
		_categoryType = categoryType;
		_drops = new FastList<L2DropData>(0);
		_categoryChance = 0;
		_categoryBalancedChance = 0;
	}

	public void addDropData(L2DropData drop, boolean raid)
	{
        boolean found = false;
        
	    if (drop.isQuestDrop()) {
	    //if (_questDrops == null)
	    //	_questDrops = new FastList<L2DropData>(0);
	    //_questDrops.add(drop);
	    } 
	    else 
	    {
            if (Config.CUSTOM_DROPLIST_TABLE)
            {
                // If the drop exists is replaced
                for (L2DropData d : _drops)
                {
                    if (d.getItemId() == drop.getItemId())
                    {
                        d.setMinDrop(drop.getMinDrop());
                        d.setMaxDrop(drop.getMaxDrop());
                        if (d.getChance() != drop.getChance())
                        {
                            // Re-calculate Chance
                            _categoryChance -= d.getChance();
                            _categoryBalancedChance -= Math.min((d.getChance() * Config.RATE_DROP_ITEMS), L2DropData.MAX_CHANCE);
                            d.setChance(drop.getChance());
                            _categoryChance += d.getChance();
                            _categoryBalancedChance += Math.min((d.getChance() * Config.RATE_DROP_ITEMS), L2DropData.MAX_CHANCE);
                        }
                        found = true;
                        break;
                    }
                }
            }
	        
            if (!found)
            {
                _drops.add(drop);
                _categoryChance += drop.getChance();
                // for drop selection inside a category: max 100 % chance for getting an item, scaling all values to that.
                _categoryBalancedChance += Math.min((drop.getChance()*(raid?Config.RATE_DROP_ITEMS_BY_RAID : Config.RATE_DROP_ITEMS)),L2DropData.MAX_CHANCE);
            }
	    }
	}

    public FastList<L2DropData> getAllDrops()
    {
    	return _drops;
    }

    public void clearAllDrops()
    {
    	_drops.clear();
    }

    public boolean isSweep()
    {
    	return (getCategoryType()==-1);
    }

    // this returns the chance for the category to be visited in order to check if
    // drops might come from it.  Category -1 (spoil) must always be visited
    // (but may return 0 or many drops)
    public int getCategoryChance()
    {
    	if (getCategoryType() >= 0)
    		return _categoryChance;
    	else
    		return L2DropData.MAX_CHANCE;
    }

    public int getCategoryBalancedChance()
    {
    	if (getCategoryType() >= 0)
    		return _categoryBalancedChance;
    	else
    		return L2DropData.MAX_CHANCE;
    }

    public int getCategoryType()
    {
    	return _categoryType;
    }

    /**
     * useful for seeded conditions...the category will attempt to drop only among
     * items that are allowed to be dropped when a mob is seeded.
     * Previously, this only included adena.  According to sh1ny, sealstones are also
     * acceptable drops.
     * if no acceptable drops are in the category, nothing will be dropped.
     * otherwise, it will check for the item's chance to drop and either drop
     * it or drop nothing.
     *
     * @return acceptable drop when mob is seeded, if it exists.  Null otherwise.
     */
    public synchronized L2DropData dropSeedAllowedDropsOnly()
    {
    	FastList<L2DropData> drops = new FastList<L2DropData>();
    	int subCatChance = 0;
    	for (L2DropData drop : getAllDrops())
        {
    		if ((drop.getItemId() == 57) || (drop.getItemId() == 6360)|| (drop.getItemId() == 6361)|| (drop.getItemId() == 6362))
    		{
            	drops.add(drop);
        		subCatChance += drop.getChance();
    		}
        }

    	// among the results choose one.
        int randomIndex = Rnd.get(subCatChance);
        int sum = 0;
        for (L2DropData drop : drops)
        {
        	sum += drop.getChance();

        	if (sum > randomIndex)       // drop this item and exit the function
        	{
        		drops.clear();
        		drops=null;
        		return drop;
        	}
        }
          // since it is still within category, only drop one of the acceptable drops from the results.
    	return null;
    }

/**
 * ONE of the drops in this category is to be dropped now.
 * to see which one will be dropped, weight all items' chances such that
 * their sum of chances equals MAX_CHANCE.
 * since the individual drops have their base chance, we also ought to use the
 * base category chance for the weight.  So weight = MAX_CHANCE/basecategoryDropChance.
 * Then get a single random number within this range.  The first item
 * (in order of the list) whose contribution to the sum makes the
 * sum greater than the random number, will be dropped.
 *
 * Edited: How _categoryBalancedChance works in high rate servers:
 * Let's say item1 has a drop chance (when considered alone, without category) of
 * 1 % * RATE_DROP_ITEMS and item2 has 20 % * RATE_DROP_ITEMS, and the server's
 * RATE_DROP_ITEMS is for example 50x. Without this balancer, the relative chance inside
 * the category to select item1 to be dropped would be 1/26 and item2 25/26, no matter
 * what rates are used. In high rate servers people usually consider the 1 % individual
 * drop chance should become higher than this relative chance (1/26) inside the category,
 * since having the both items for example in their own categories would result in having
 * a drop chance for item1 50 % and item2 1000 %. _categoryBalancedChance limits the
 * individual chances to 100 % max, making the chance for item1 to be selected from this
 * category 50/(50+100) = 1/3 and item2 100/150 = 2/3.
 * This change doesn't affect calculation when drop_chance * RATE_DROP_ITEMS < 100 %,
 * meaning there are no big changes for low rate servers and no changes at all for 1x
 * servers.
 *
 * @return selected drop from category, or null if nothing is dropped.
 */
    public synchronized L2DropData dropOne(boolean raid)
    {
        int randomIndex = Rnd.get(getCategoryBalancedChance());
        int sum = 0;
        for (L2DropData drop : getAllDrops())
        {
        	sum += Math.min((drop.getChance()*(raid?Config.RATE_DROP_ITEMS_BY_RAID : Config.RATE_DROP_ITEMS)),L2DropData.MAX_CHANCE);

        	if (sum >= randomIndex)       // drop this item and exit the function
        		return drop;
        }
        return null;
    }
}
