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


using Newtonsoft.Json;
using Amazon.DynamoDBv2;
using Amazon.DynamoDBv2.Model;
using Amazon.DynamoDBv2.DocumentModel;
using Amazon.Runtime;


using ServerCore;
using ServerBase;
using MetaAssets;


using SESSION_ID = System.Int32;
using META_ID = System.UInt32;
using ENTITY_GUID = System.String;
using ACCOUNT_ID = System.String;
using OWNER_GUID = System.String;
using USER_GUID = System.String;
using CHARACTER_GUID = System.String;
using ITEM_GUID = System.String;


namespace ServerCommon;

public class DBQEntityReadToAttribute<TDoc> : QueryExecutorBase
    where TDoc : DynamoDbDocBase, new()
{
    private EntityBase m_owner_of_entity_attribute;

    private string m_combination_key_for_pk = string.Empty;
    private string m_combination_key_for_sk = string.Empty;

    private string m_pk = string.Empty;
    private string m_sk = string.Empty;

    private readonly List<DynamoDbDocBase> m_to_read_doc_bases = new();
    private readonly List<Type> m_copy_to_target_entity_attribute_types;

    public DBQEntityReadToAttribute( EntityBase ownerOfEntityAttribute
                                   , string combinationKeyForPK, Type[] copyToTargetEnityAttributeTypes)
        : base(typeof(DBQEntityReadToAttribute<TDoc>).Name)
    {
        m_owner_of_entity_attribute = ownerOfEntityAttribute;

        m_combination_key_for_pk = combinationKeyForPK;
        m_copy_to_target_entity_attribute_types = copyToTargetEnityAttributeTypes.ToList<Type>();
    }

    public DBQEntityReadToAttribute( EntityBase ownerOfEntityAttribute
                                   , string combinationKeyForPK, string combinationKeyForSK, Type[] copyToTargetEnityAttributeTypes)
        : base(typeof(DBQEntityReadToAttribute<TDoc>).Name)
    {
        m_owner_of_entity_attribute = ownerOfEntityAttribute;

        m_combination_key_for_pk = combinationKeyForPK;
        m_combination_key_for_sk = combinationKeyForSK;
        m_copy_to_target_entity_attribute_types = copyToTargetEnityAttributeTypes.ToList<Type>();
    }

    //=====================================================================================
    // DB 쿼리 직전에 준비해야 할 로직들을 작성한다.
    //=====================================================================================
    public override async Task<Result> onPrepareQuery()
    {
        await Task.CompletedTask;

        var result = new Result();
        var err_msg = string.Empty;

        var owner = getOwner();
        NullReferenceCheckHelper.throwIfNull(owner, () => $"owner is null !!!");

        (result, var primary_key) = await DynamoDBDocBaseHelper.makePrimaryKey<TDoc>(m_combination_key_for_pk, m_combination_key_for_sk);            
        if(result.isFail())
        {
            err_msg = $"Failed to makePrimaryKey<TDoc>() !!! : {result.toBasicString()}, {typeof(TDoc).Name} - {toBasicString()}, {owner.toBasicString()}";
            Log.getLogger().error(err_msg);
            return result;
        }
        NullReferenceCheckHelper.throwIfNull(primary_key, () => $"primary_key is null !!! - {owner.toBasicString()}");

        m_pk = primary_key.PK;
        m_sk = primary_key.SK;

        return result;
    }

    //=====================================================================================
    // onPrepareQuery()를 성공할 경우 호출된다.
    //=====================================================================================
    public override async Task<Result> onQuery()
    {
        var result = new Result();
        var err_msg = string.Empty;

        var owner = getOwner();
        NullReferenceCheckHelper.throwIfNull(owner, () => $"owner is null !!!");

        var query_batch = getQueryBatch();
        NullReferenceCheckHelper.throwIfNull(query_batch, () => $"query_batch is null !!! - {owner.toBasicString()}");

        var server_logic = ServerLogicApp.getServerLogicApp();
        var dynamo_db_connector = query_batch.getDynamoDbConnector();

        QueryOperationConfig? query_config = null;
        if (true == m_sk.isNullOrWhiteSpace())
        {
            query_config = dynamo_db_connector.makeQueryConfigForReadByPKSK(m_pk);
        }
        else
        {
            query_config = dynamo_db_connector.makeQueryConfigForReadByPKSK(m_pk, m_sk);
        }

        (result, var read_docs) = await dynamo_db_connector.simpleQueryDocTypesWithQueryOperationConfig<TDoc>(query_config, eventTid: query_batch.getTransId());
        if(result.isFail())
        {
            return result;
        }

        var msg = $"{this.getTypeName()} : readCount:{read_docs.Count}, isUseTransact:{query_batch.isUseTransact} - TransId:{query_batch.getTransId()}";
        Log.getLogger().info(msg);

        foreach ( var read_doc in read_docs )
        {
            foreach (var target_entity_attribute_type in m_copy_to_target_entity_attribute_types)
            {
                var target_entity_attribute_base = getOwnerOfEntityAttribute().getOriginEntityAttribute(target_entity_attribute_type);
                if (null == target_entity_attribute_base)
                {
                    err_msg = $"Not found Target getOriginEntityAttribute() !!!"
                            + $" : to:{target_entity_attribute_type.Name}, from:{typeof(TDoc).Name}, ownerOfAttribute:{getOwnerOfEntityAttribute().toBasicString()}"
                            + $" - {toBasicString()}, {owner.toBasicString()}";
                    result.setFail(ServerErrorCode.EntityAttributeNotFound, err_msg);
                    Log.getLogger().error(result.toBasicString());
                    return result;
                }

                result = await ServerBase.DataCopyHelper.copyEntityAttributeFromDocs(target_entity_attribute_base, new List<DynamoDbDocBase>() { read_doc });
                if (result.isFail())
                {
                    err_msg = $"Failed to copyEntityAttributeFromDocs() !!! : {result.toBasicString()}, ownerOfAttribute:{getOwnerOfEntityAttribute().toBasicString()}"
                            + $" - {toBasicString()}, {owner.toBasicString()}";
                    Log.getLogger().error(result.toBasicString());
                    return result;
                }
            }

            m_to_read_doc_bases.Add(read_doc);
        }

        return result;
    }

    public List<DynamoDbDocBase> getToReadDocBases() => m_to_read_doc_bases;

    //=====================================================================================
    // DB 쿼리를 성공하고, doFnCommit()가 QueryResultType.NotCalledQueryFunc를 반환할 경우 호출된다.
    //=====================================================================================
    public override async Task onQueryResponseCommit()
    {
        await Task.CompletedTask;
        return;
    }

    //=====================================================================================
    // DB 쿼리를 실패하고, doFnRollback()가 QueryResultType.NotCalledQueryFunc를 반환할 경우 호출된다.
    //=====================================================================================
    public override async Task onQueryResponseRollback(Result errorResult)
    {
        await Task.CompletedTask;
        return;
    }

    public EntityBase getOwnerOfEntityAttribute() => m_owner_of_entity_attribute;
}