using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Text;
using System.Threading.Tasks;


using ServerCore; using ServerBase;


namespace ServerBase;


public class EntityAggregator<TKey, TCounterType>
    where TKey : ITuple
    where TCounterType : struct
{
    private readonly ConcurrentDictionary<TKey, TCounterType> m_counters = new();

    public EntityAggregator() 
    {            
    }

    public void reset()
    {
        m_counters.Clear();
    }

    public void incCounter(TKey key, TCounterType toIncValue, Func<TCounterType, TCounterType, TCounterType> fnUpdate)
    {
        var add_counter = delegate (TKey key)
        {
            return toIncValue;
        };

        var update_recorder = delegate (TKey key, TCounterType currValue)
        {
            return fnUpdate(currValue, toIncValue);
        };

        m_counters.AddOrUpdate(key, add_counter, update_recorder);
    }

    public void decCounter(TKey key, TCounterType toDecValue, Func<TCounterType, TCounterType, TCounterType> fnUpdate)
    {
        var add_counter = delegate (TKey key)
        {
            return toDecValue;
        };

        var update_recorder = delegate (TKey key, TCounterType currValue)
        {
            return fnUpdate(currValue, toDecValue);
        };

        m_counters.AddOrUpdate(key, add_counter, update_recorder);
    }

    public TCounterType getCounter(TKey key, TCounterType defaultValue)
    {
        if(false == m_counters.TryGetValue(key, out var found_counter))
        {
            return defaultValue;
        }

        return found_counter;
    }
    
    public ConcurrentDictionary<TKey, TCounterType> getCounters() => m_counters;
}