FromOptionsWithoutRepeatsDropRule.cs

Go to the documentation of this file.

using System.Collections.Generic;
 
namespace Terraria.GameContent.ItemDropRules;
 
public class FromOptionsWithoutRepeatsDropRule : IItemDropRule
{
    public int[] dropIds;
 
    public int dropCount;
 
    private List<int> _temporaryAvailableItems = new List<int>();
 
    public List<IItemDropRuleChainAttempt> ChainedRules { get; private set; }
 
    public FromOptionsWithoutRepeatsDropRule(int dropCount, params int[] options)
    {
        this.dropCount = dropCount;
        dropIds = options;
        ChainedRules = new List<IItemDropRuleChainAttempt>();
    }
 
    public bool CanDrop(DropAttemptInfo info)
    {
        return true;
    }
 
    public ItemDropAttemptResult TryDroppingItem(DropAttemptInfo info)
    {
        _temporaryAvailableItems.Clear();
        _temporaryAvailableItems.AddRange(dropIds);
        for (int i = 0; i < dropCount; i++)
        {
            if (_temporaryAvailableItems.Count <= 0)
            {
                break;
            }
            int index = info.rng.Next(_temporaryAvailableItems.Count);
            CommonCode.DropItemFromNPC(info.npc, _temporaryAvailableItems[index], 1);
            _temporaryAvailableItems.RemoveAt(index);
        }
        ItemDropAttemptResult result = default(ItemDropAttemptResult);
        result.State = ItemDropAttemptResultState.Success;
        return result;
    }
 
    public void ReportDroprates(List<DropRateInfo> drops, DropRateInfoChainFeed ratesInfo)
    {
        float parentDroprateChance = ratesInfo.parentDroprateChance;
        int num = dropIds.Length;
        float num2 = 1f;
        int num3 = 0;
        while (num3 < dropCount && num > 0)
        {
            num2 *= (float)(num - 1) / (float)num;
            num3++;
            num--;
        }
        float dropRate = (1f - num2) * parentDroprateChance;
        for (int i = 0; i < dropIds.Length; i++)
        {
            drops.Add(new DropRateInfo(dropIds[i], 1, 1, dropRate, ratesInfo.conditions));
        }
        Chains.ReportDroprates(ChainedRules, 1f, drops, ratesInfo);
    }
}