using Amazon.DynamoDBv2.DocumentModel;
using ServerCommon;
using ServerCore; using ServerBase;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

namespace GameServer
{
    internal static class NicknameHelper
    {
        public static async Task<(Result, List<string>?)> searchNicknameBeginWith(string searchString)
        {
            var result = new Result();
            var nicknames = new List<string>();
            var err_msg = string.Empty;

            var server_logic = GameServerApp.getServerLogic();
            var db_client = server_logic.getDynamoDbClient();
            ArgumentNullException.ThrowIfNull(db_client);

            (result, var make_primary_key) = await DynamoDBDocBaseHelper.makePrimaryKey<UserNicknameRegistryDoc>(DynamoDbClient.PK_GLOBAL, searchString.ToLower());
            if (result.isFail())
            {
                return (result, null);
            }

            NullReferenceCheckHelper.throwIfNull(make_primary_key, () => $"make_primary_key is null !!! - searchString: {searchString}");
            
            var query_config = db_client.makeQueryConfigWithPKSKBySKBeginWith( make_primary_key.PK, make_primary_key.SK
                                                                             , new QueryOperationConfig() );      
            ArgumentNullException.ThrowIfNull(query_config);
            (result, var read_docs) = await db_client.simpleQueryDocTypesWithQueryOperationConfig<UserNicknameRegistryDoc>(query_config);
            if (result.isFail())
            {
                return (result, null);
            }

            foreach (var doc in read_docs)
            {
                var user_nickname_registry_attrib = doc.getAttrib<UserNicknameRegistryAttrib>();
                NullReferenceCheckHelper.throwIfNull(user_nickname_registry_attrib, () => $"user_nickname_registry_attrib is null !!! - searchString: {searchString}");

                nicknames.Add(user_nickname_registry_attrib.Nickname);
            }

            return (result, nicknames);
        }

        public static async Task<(Result, UserNicknameRegistryAttrib?)> findNickname(string toCheckNickname)
        {
            var result = new Result();
            var err_msg = string.Empty;

            var server_logic = ServerLogicApp.getServerLogicApp();
            var dynamo_db_client = server_logic.getDynamoDbClient();
            NullReferenceCheckHelper.throwIfNull(dynamo_db_client, () => "dynamo_db_client is null !!!");

            if (toCheckNickname.isNullOrWhiteSpace())
            {
                err_msg = $"Nickname is Null or WhiteSpace !!!";
                result.setFail(ServerErrorCode.UserNicknameEmpty, err_msg);
                Log.getLogger().error(result.toBasicString());

                return (result, null);
            }

            (result, var make_primary_key) = await DynamoDBDocBaseHelper.makePrimaryKey<UserNicknameRegistryDoc>(DynamoDbClient.PK_GLOBAL, toCheckNickname.ToLower());
            if (result.isFail())
            {
                return (result, null);
            }
            
            NullReferenceCheckHelper.throwIfNull(make_primary_key, () => $"make_primary_key is null !!! - toCheckNickname: {toCheckNickname}");
            
            var query_config = dynamo_db_client.makeQueryConfigForReadByPKSK(make_primary_key.PK, make_primary_key.SK);
            ArgumentNullException.ThrowIfNull(query_config);
            (result, var found_nicknames) = await dynamo_db_client.simpleQueryDocTypesWithQueryOperationConfig<UserNicknameRegistryDoc>(query_config);
            if (result.isFail())
            {
                return (result, null);
            }

            if (found_nicknames.Count == 0)
            {
                result.setFail(ServerErrorCode.TargetUserNotFound);
                return (result, null);
            }

            var nickname_attrib = found_nicknames[0].getAttrib<UserNicknameRegistryAttrib>();
            if (nickname_attrib == null)
            {
                result.setFail(ServerErrorCode.AttribNotFound);
                return (result, null);
            }

            return (result, nickname_attrib);
        }
    }
}