using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Linq;
using System.Threading.Tasks;
using LCU.API.Collections.RepoApi.Exceptions;
using LCU.API.Collections.RepoApi.Models;
using LCU.Shared.Collections.RepoApiLib.Exceptions;
using LCU.Shared.Collections.RepoApiLib.Models;
using LCU.Shared.Collections.RepoApiLib.Repositories;
using Serilog;

namespace LCU.API.Collections.RepoApi.Services
{
    public class EventAlertService : IEventAlertService
    {
        private readonly IEventAlertRepository _eventAlertRepository;
        private readonly IUnitOfWork _unitOfWork;
        private const string RedeemedStatus = "REDEEMED";
        private const string CancelledStatus = "RECA";
        private readonly IRepoAccountRepository _accountRepository;

        public EventAlertService(
            IEventAlertRepository eventAlertRepository,
            IUnitOfWork unitOfWork,
            IRepoAccountRepository accountRepository)
        {
            _eventAlertRepository = eventAlertRepository;
            _unitOfWork = unitOfWork;
            _accountRepository = accountRepository;
        }

        public async Task<IEnumerable<EventAlert>> ListAll()
        {
            try
            {
                return await _eventAlertRepository.ListAllAsync();
            }
            catch (Exception ex)
            {
                Log.Error(ex, "Failure retrieving  All Event Alerts");
                throw new ServerErrorException();
            }
        }

        public async Task<IEnumerable<EventAlert>> ListUnread()
        {
            try
            {
                return await _eventAlertRepository.ListUnreadAsync();
            }
            catch (Exception ex)
            {
                Log.Error(ex, "Failure retrieving Unread Event Alerts");
                throw new ServerErrorException();
            }
        }

        public async Task<IEnumerable<EventAlert>> ListWithinDateRange(DateTime start, DateTime end)
        {
            try
            {
                return await _eventAlertRepository.ListWithinDateRangeAsync(start, end);
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Failure retrieving Event Alerts between {start} and {end}");
                throw new ServerErrorException();
            }
        }

        public async Task<IEnumerable<EventAlert>> ListActionNeeded()
        {
            try
            {
                var repoNoAuction = await _eventAlertRepository.ListRepoNoAuctionAsync();
                var repoNoCompany = await _eventAlertRepository.ListRepoNoCompanyAsync();
                var o4rNoCompany = await _eventAlertRepository.ListO4rNoCompanyAsync();
                var retitle = await _eventAlertRepository.ListReadyForRetitleAsync();
                var floorUpdateFail = await _eventAlertRepository.ListFloorUpdateFailedAsync();
                var setFloor = await _eventAlertRepository.ListFloorNeedsSettingAsync();

                return repoNoAuction.Concat(repoNoCompany).Concat(o4rNoCompany).Concat(retitle).Concat(floorUpdateFail).Concat(setFloor).ToList();
            }
            catch (Exception ex)
            {
                Log.Error(ex, "Failure retrieving Action Needed Event Alerts");
                throw new ServerErrorException();
            }
        }

        public async Task<EventAlert> SaveAsync(EventAlert eventAlert)
        {
            try
            {
                if (IsStatusCancelledOrRedeemed(eventAlert.RepoId.Value).Result)
                {
                    throw new UnwantedStatusException(eventAlert.RepoId.Value, eventAlert.AccountNo);
                }
                await _eventAlertRepository.AddAsync(eventAlert);
                await _unitOfWork.CompleteAsync();
                return eventAlert;
            }
            catch (DuplicateResourceException ex)
            {
                Log.Debug(ex, $"SaveAsync: Valid Alert Already Exists eventAlert:{eventAlert}", eventAlert);
                throw ex;
            }
            catch(UnwantedStatusException ex)
            {
                Log.Error(ex, $"SaveAsync: Status of Repo is Redeemed or Cancelled. Event Alert: {eventAlert} not created", eventAlert);
                throw;
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"SaveAsync: Failure saving Event Alert: {eventAlert}", eventAlert);
                throw new ServerErrorException();
            }
        }

        public async Task<IEnumerable<EventAlert>> SaveRangeAsync(List<EventAlert> eventAlerts)
        {
            IEnumerable<EventAlert> addedEventAlerts = new List<EventAlert>();
            try
            {
                addedEventAlerts = await _eventAlertRepository.AddRangeAsync(eventAlerts);
                await _unitOfWork.CompleteAsync();
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"EventAlertService: Failure Saving Range Of Event Alerts: {eventAlerts}", eventAlerts);
            }

            return addedEventAlerts;
        }

            

        public async Task<EventAlert> Get(int id)
        {
            EventAlert eventAlert;
            try
            {
                eventAlert = await _eventAlertRepository.FindByIdAsync(id);
                await _unitOfWork.CompleteAsync();
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Failure retrieving Event Alert with id: {id}");
                throw new ServerErrorException();
            }

            if (eventAlert == null)
            {
                throw new NotFoundException($"EventAlert with id {id} not found.");
            }

            return eventAlert;
        }

        public async Task<EventAlert> UpdateAsync(EventAlert eventAlert, AppUser user)
        {

            EventAlert existingEventAlert = null;
            try
            {
                existingEventAlert = await _eventAlertRepository.FindByIdAsync(eventAlert.Id);
            }
            catch(Exception ex)
            {
                Log.Error(ex, $"Failed to find existing event alert with Id: {eventAlert.Id}, user: {user}", eventAlert, user);
                throw new ServerErrorException();
            }

            if (existingEventAlert == null)
            {
                throw new NotFoundException($"EventAlert with id {eventAlert.Id} not found.");
            }

            existingEventAlert.Message = eventAlert.Message;
            existingEventAlert.SubMessage = eventAlert.SubMessage;
            if (existingEventAlert.DateMarkedRead == null && eventAlert.DateMarkedRead != null)
            {
                existingEventAlert.MarkedReadBy = user.FirstName + " " + user.LastName;
                existingEventAlert.DateMarkedRead = eventAlert.DateMarkedRead;
            }

            try
            {
                _eventAlertRepository.Update(existingEventAlert);
                await _unitOfWork.CompleteAsync();
                return (existingEventAlert);
            }
            catch (SqlException ex)
            {
                Log.Error(ex, $"SQL Failure updating Event Alert: {eventAlert}", eventAlert);
                throw new ServerErrorException();
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Failure updating Event Alert {eventAlert}", eventAlert);
                throw new ServerErrorException();
            }
        }

        public async Task<EventAlert> DeleteAsync(int id)
        {
            EventAlert existingEventAlert = null;
            try
            {
                existingEventAlert = await _eventAlertRepository.FindByIdAsync(id);
            }
            catch(Exception ex)
            {
                Log.Error(ex, $"Failed to find existing event alert with Id: {id}.");
                throw new ServerErrorException();
            }
            if (existingEventAlert == null)
            {
                throw new NotFoundException($"EventAlert with id {id} not found.");
            }

            try
            {
                _eventAlertRepository.Remove(existingEventAlert);
                await _unitOfWork.CompleteAsync();
                return existingEventAlert;
            }
            catch (SqlException ex)
            {
                Log.Error(ex, $"SQL Failure deleting Event Alert with id {id}");
                throw new ServerErrorException();
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Failure deleting Event Alert with id {id}");
                throw new ServerErrorException();
            }
        }

        public async Task<IEnumerable<EventAlert>> MarkAllAsRead(string accountNo)
        {
            IEnumerable<EventAlert> existingEventAlerts = null;
            try
            {
                existingEventAlerts = await _eventAlertRepository.ListUnreadByAccountNoAsync(accountNo);
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Failed to find existing event alerts with accountNo: {accountNo}");
                throw new ServerErrorException();
            }

            if (existingEventAlerts == null)
            {
                throw new NotFoundException($"EventAlerts for accountNo: {accountNo} not found.");
            }

            var ret = new List<EventAlert>();

            foreach (EventAlert eventAlert in existingEventAlerts)
            {
                eventAlert.MarkedReadBy = "System";
                eventAlert.DateMarkedRead = DateTime.Now;

                try
                {
                    _eventAlertRepository.Update(eventAlert);
                    ret.Add(eventAlert);
                }
                catch (SqlException ex)
                {
                    Log.Error(ex, $"SQL Failure updating Event Alert: {eventAlert} in the list {existingEventAlerts}. Will not commit any changes.", eventAlert);
                    throw new ServerErrorException();
                }
                catch (Exception ex)
                {
                    Log.Error(ex, $"Failure updating Event Alert {eventAlert} in the list {existingEventAlerts}. Will not commit any changes", eventAlert);
                    throw new ServerErrorException();
                }
            }
            await _unitOfWork.CompleteAsync();
            return ret;
        }

        private async Task<bool> IsStatusCancelledOrRedeemed(int repoId)
        {
            var repo = await _accountRepository.FindByIdAsync(repoId);
            if (repo == null)
            {
                return false;
            }

            return repo.Status.Equals(CancelledStatus) || repo.Status.Equals(RedeemedStatus);
        }
    }
}