using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using CRMDAL.DTO.SLA;
using CRMDAL.Query.SLA;
using GB5Shared.DTO.Framework.Criteria;
using GB5Shared.DTO.Framework.Login;
using GB5Shared.GB5Exception;
using GB5Shared.QueryExecutor;
using GB5Shared.Resource.Response;
using GB5Shared.Validation;
using Newtonsoft.Json;

namespace CRMDAL.CustomCode.SLA
{
    public class SLADAL : ISLADAL
    {
        private readonly IQueryExecutor _QueryExecutor;
        private readonly IValidation _Validation;

        public SLADAL(IQueryExecutor QueryExecutor, IValidation Validation)
        {
            _QueryExecutor = QueryExecutor;
            _Validation = Validation;
        }

        public async Task<string> GetSLA(int SLAId, LoginDTO LoginDTO)
        {
            try
            {
                var sql = SLAQB.GET_SLA;
                var parameters = new { SLAid = SLAId };

                var SLADict = new Dictionary<int, SLADTO>();

                var result = await _QueryExecutor.QueryMultiMapAsync<SLADTO, SLADetailDTO, SLADTO>(
                    LoginDTO,
                    sql,
                    (parent, child) =>
                    {
                        if (!SLADict.TryGetValue(parent.SLAId, out var existingParent))
                        {
                            existingParent = parent;
                            existingParent.SLADetailArray = new List<SLADetailDTO>();
                            SLADict[parent.SLAId] = existingParent;
                        }

                        if (child != null && child.SLADetailId != 0)
                        {
                            existingParent.SLADetailArray.Add(child);
                        }

                        return existingParent;
                    },
                    parameters,
                    splitOn: "SLADETAILID"
                );

                var finalResult = SLADict.Values.FirstOrDefault();
                return JsonConvert.SerializeObject(finalResult);
            }
            catch (Exception ex)
            {
                throw new Exception($"Failed to retrieve SLA: {ex.Message}", ex);
            }
        }


        public async Task<int> SaveSLA(SLADTO SLADTO, LoginDTO LoginDTO)
        {
            try
            {
                // SQL Server queries only
                string SLASql = SLAQB.SAVE_SLA;
                string detailSql = SLAQB.SAVE_SLA_DETAIL;
                string countSql = SLAQB.GET_SLA_COUNT;

                // DUPLICATE CHECK
                int existingCount = await _QueryExecutor.ExecuteScalarAsync<int>(LoginDTO, countSql,
                    new
                    {
                        SLADTO.SLAId
                    });

                if (existingCount > 0)
                {
                    throw new MethodNotAllowedException(
                        "Duplicate SLA record exists."
                    );
                }

                // TRANSACTION BUILD
                var statements = new List<(string sql, object param)>
        {
            (SLASql, SLADTO)
        };

                if (SLADTO.SLADetailArray?.Count > 0)
                {
                    foreach (var detail in SLADTO.SLADetailArray)
                    {
                        detail.SLAId = SLADTO.SLAId;
                        statements.Add((detailSql, detail));
                    }
                }

                await _QueryExecutor.ExecuteInTransactionAsync(LoginDTO, statements);

                return SLADTO.SLAId;
            }
            catch (Exception ex)
            {
                throw new Exception(
                    $"{ErrorResponse.SaveErrorMessage}: {ex.Message}", ex);
            }
        }


        public async Task<int> UpdateSLA(SLADTO SLADTO, LoginDTO login)
        {
            var statements = new List<(string sql, object param)>();
            statements.Add((SLAQB.UPDATE_SLA, SLADTO));

            foreach (var d in SLADTO.SLADetailArray)
            {
                d.SLAId = SLADTO.SLAId;
                if (d.SLADetailId == 0)
                    statements.Add((SLAQB.SAVE_SLA_DETAIL, d));
                else
                    statements.Add((SLAQB.UPDATE_SLA_DETAIL, d));
            }

            await _QueryExecutor.ExecuteInTransactionAsync(login, statements);
            return SLADTO.SLAId;
        }

        public async Task<int> DeleteSLADetail(int SLAId, LoginDTO LoginDTO)
        {
            try
            {
                return await _QueryExecutor.ExecuteAsync(
                    LoginDTO,
                    SLAQB.DELETE_SLA_DETAIL,
                    new { SLAid = SLAId }
                );
            }
            catch (Exception ex)
            {
                throw new Exception($"Error while deleting SLA Detail for ID {SLAId}", ex);
            }
        }


        public async Task<int> DeleteSLA(int SLAId, LoginDTO LoginDTO)
        {
            try
            {
                return await _QueryExecutor.ExecuteAsync(
                    LoginDTO,
                    SLAQB.DELETE_SLA,
                    new { SLAid = SLAId }
                );
            }
            catch (Exception ex)
            {
                throw new Exception($"Error while deleting SLA with ID {SLAId}", ex);
            }
        }

        public async Task<string> GetSelectListSLA(CriteriaDTO CriteriaDTO, LoginDTO LoginDTO)
        {
            try
            {
                string SQL = SLAQB.GET_SELECTLIST_SLA;
                var Result = await _QueryExecutor.QueryAsync<SLAPicklistDTO>(LoginDTO, SQL, null!);
                string Json = JsonConvert.SerializeObject(Result);
                return Json;
            }
            catch (Exception)
            {
                throw;
            }
        }
    }
}