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


using ServerCore; using ServerBase;


namespace ServerBase;

public class DynamoDbQueryExceptionNotifier
{
    public const string Success                             = "None";                               // 쿼리 성공
    public const string ConditionalCheckFailed              = "ConditionalCheckFailed";             // 쿼리 실패 : 조건들이 충족하지 못해 실패 했다.
    public const string ItemCollectionSizeLimitExceeded     = "ItemCollectionSizeLimitExceeded";    // 쿼리 실패 : 아이템 제한 개수 초과로 실패 했다.

    public class ExceptionHandler
    {
        public ExceptionHandler(string reasonCode, ServerErrorCode returnToErrorCode) 
        {
            ReasonCode = reasonCode;
            ReturnToErrorCode = returnToErrorCode;
        }

        public bool hasReasonCode(string reasonCode)
        {
            return ReasonCode.Equals(reasonCode, StringComparison.OrdinalIgnoreCase);
        }

        public string ReasonCode { get; set; }

        public ServerErrorCode ReturnToErrorCode { get; set; }
    }

    private Int32 m_query_seq_no = 0;
    private readonly Dictionary<Int32, ExceptionHandler> m_exception_handlers = new();

    public DynamoDbQueryExceptionNotifier() 
    { 
    }

    public bool registerExceptionHandler(ExceptionHandler? exceptionHandler)
    {
        m_query_seq_no++;

        if(null == exceptionHandler)
        {
            return false;
        }

        if(true == m_exception_handlers.ContainsKey(m_query_seq_no))
        {
            return false;
        }

        m_exception_handlers[m_query_seq_no] = exceptionHandler;
        return true;
    }

    public ExceptionHandler? findExceptionHandler(Int32 querySeqNo, string reasonCode)
    {
        if(false == m_exception_handlers.TryGetValue(querySeqNo, out var exception_handler))
        {
            return null;
        }

        if(false == exception_handler.hasReasonCode(reasonCode))
        {
            return null;
        }

        return exception_handler;
    }
}