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.API.Collections.RepoApi.Models.Filters;
using LCU.API.Collections.RepoApi.Models.Requests;
using LCU.Shared.Collections.RepoApiLib.Exceptions;
using LCU.Shared.Collections.RepoApiLib.Models;
using LCU.Shared.Collections.RepoApiLib.Models.Producer;
using LCU.Shared.Collections.RepoApiLib.Models.Results;
using LCU.Shared.Collections.RepoApiLib.Repositories;
using Serilog;

namespace LCU.API.Collections.RepoApi.Services
{
    public class RepoAccountService : IRepoAccountService
    {
        private readonly IRepoAccountRepository _repoAccountRepository;
        private readonly IRepoStatusChangeRepository _repoStatusChangeRepository;
        private readonly IRepoManualStatusRepository _repoManualStatusRepository;
        private readonly IUnitOfWork _unitOfWork;

        public RepoAccountService(
            IRepoAccountRepository repoAccountRepository,
            IRepoStatusChangeRepository repoStatusChangeRepository,
            IRepoManualStatusRepository repoManualStatusRepository,
            IUnitOfWork unitOfWork)
        {
            _repoAccountRepository = repoAccountRepository;
            _repoStatusChangeRepository = repoStatusChangeRepository;
            _repoManualStatusRepository = repoManualStatusRepository;
            _unitOfWork = unitOfWork;
        }

        public async Task<PagedResult<RepoAccount>> ListAll(PageFilter pageFilter, RepoAccountPostFilter repoAccountFilter)
        {
            try
            {
                return await _repoAccountRepository.ListAsync(
                    repoAccountFilter != null ? repoAccountFilter.RepoIdList : new List<int?>(), 
                    pageFilter.Page,
                    pageFilter.Limit,
                    repoAccountFilter?.Status,
                    repoAccountFilter?.AuctionHouseId,
                    repoAccountFilter?.RepoCompanyId,
                    repoAccountFilter?.OnlyOpenAccounts);
            }
            catch (Exception ex)
            {
                Log.Error(ex, "Failure retrieving RepoAccounts");
                throw new ServerErrorException();
            }
        }

        public async Task<RepoAccount> FindByAuctionAssignmentId(int auctionAssignmentId)
        {
            try
            {
                return await _repoAccountRepository.FindByAuctionAssignmentIdAsync(auctionAssignmentId);
            }
            catch (Exception ex)
            {
                Log.Error(ex, "Failure retrieving RepoAccount");
                throw new ServerErrorException();
            }
        }

        public async Task<RepoAccount> SaveAsync(RepoAccount repoAccount)
        {
            try
            {
                var newAccount = await _repoAccountRepository.AddAsync(repoAccount);
                RepoStatusChange change = new RepoStatusChange()
                {
                    RepoId = newAccount.RepoId,
                    ChangedBy = "System",
                    StatusFrom = "None",
                    StatusTo = repoAccount.Status,
                    ChangedDate = DateTime.Now
                };
                await _repoStatusChangeRepository.AddAsync(change);
                await _unitOfWork.CompleteAsync();

                return repoAccount;
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Failure saving Repo Account: {repoAccount}", repoAccount);
                throw new ServerErrorException();
            }
        }

        public async Task<RepoAccount> Get(int id)
        {
            RepoAccount repoAccount;
            try
            {
                repoAccount = await _repoAccountRepository.FindByIdAsync(id);
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Failure retrieving Repo Account with id: {id}");
                throw new ServerErrorException();
            }

            if (repoAccount == null)
            {
                throw new NotFoundException($" Repo Accounts with id {id} not found.");
            }

            return repoAccount;
        }

        public async Task<IReadOnlyCollection<RepoAccount>> GetByAccountNo(string accountNo)
        {
            IReadOnlyCollection<RepoAccount> repoAccounts;
            try
            {
                repoAccounts = await _repoAccountRepository.FindByAccountNoAsync(accountNo);
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Failure retrieving Repo Account by accountNo with accountNo: {accountNo}");
                throw new ServerErrorException();
            }

            if (repoAccounts == null || !repoAccounts.Any())
            {
                throw new NotFoundException($" Repo Accounts with id {accountNo} not found.");
            }

            return repoAccounts;
        }

        public async Task<RepoAccount> UpdateAsync(RepoAccount repoAccount, AppUser currentUser)
        {
            var existingRepoAccount = await _repoAccountRepository.FindByIdAsync(repoAccount.RepoId);

            if (existingRepoAccount == null)
            {
                throw new NotFoundException($"Repo Account with repoId {repoAccount.RepoId} not found.");
            }

            var originalStatus = existingRepoAccount.Status;
            
            existingRepoAccount.AccountLastProcessed = repoAccount.AccountLastProcessed;
            existingRepoAccount.AccountNo = repoAccount.AccountNo;
            existingRepoAccount.AccountTypeCode = repoAccount.AccountTypeCode;
            existingRepoAccount.Balance = repoAccount.Balance;
            existingRepoAccount.Bankruptcy = repoAccount.Bankruptcy;
            existingRepoAccount.Borrowers = repoAccount.Borrowers;
            existingRepoAccount.Branch = repoAccount.Branch;
            // Only one field can change in collaterals when updating the account.
            if (existingRepoAccount.Collaterals != null)
            {
                foreach (var collateral in existingRepoAccount.Collaterals)
                {
                    var newCollateral =
                        repoAccount.Collaterals.FirstOrDefault(x => x.CollateralId == collateral.CollateralId);
                    if (newCollateral != null)
                    {
                        collateral.RetitledInLandmarkName = newCollateral.RetitledInLandmarkName;
                    }
                }
            }

            //  existingRepoAccount.Collaterals = repoAccount.Collaterals; This will fail, save separately.
            existingRepoAccount.Collector = repoAccount.Collector;
            existingRepoAccount.CurrentDelinquentAmount = repoAccount.CurrentDelinquentAmount;
            existingRepoAccount.DateClosed = repoAccount.DateClosed;
            existingRepoAccount.DateFirstDelinquent = repoAccount.DateFirstDelinquent;
            existingRepoAccount.DateFirstIntellect = repoAccount.DateFirstIntellect;
            existingRepoAccount.DaysDelinquent = repoAccount.DaysDelinquent;
            existingRepoAccount.DelinquentAmount = repoAccount.DelinquentAmount;
            existingRepoAccount.DueToPayDate = repoAccount.DueToPayDate;
            existingRepoAccount.LastPaymentDate = repoAccount.LastPaymentDate;
            existingRepoAccount.LoanNo = repoAccount.LoanNo;
            existingRepoAccount.LstPmtAmt = repoAccount.LstPmtAmt;
            existingRepoAccount.ManualRedemptionDate = repoAccount.ManualRedemptionDate;
            existingRepoAccount.MemberNo = repoAccount.MemberNo;
            existingRepoAccount.O4RDate = repoAccount.O4RDate;
            existingRepoAccount.OrigAmount = repoAccount.OrigAmount;
            existingRepoAccount.OrigAccountTypeCode = repoAccount.OrigAccountTypeCode;
            existingRepoAccount.PaidSkipAmount = repoAccount.PaidSkipAmount;
            existingRepoAccount.PrimaryIndividualId = repoAccount.PrimaryIndividualId;
            existingRepoAccount.RedemptionExpiredDate = repoAccount.RedemptionExpiredDate;
            existingRepoAccount.RefundStatus = repoAccount.RefundStatus;
            existingRepoAccount.RequiredPaymentAmount = repoAccount.RequiredPaymentAmount;
            existingRepoAccount.ReferenceId = repoAccount.ReferenceId;
            existingRepoAccount.ReferenceCaseId = repoAccount.ReferenceCaseId;
            existingRepoAccount.ReferenceStatus = repoAccount.ReferenceStatus;
            existingRepoAccount.Status = repoAccount.Status;
            existingRepoAccount.SubStatus = repoAccount.SubStatus;
            existingRepoAccount.WrittenOffDate = repoAccount.WrittenOffDate;
            existingRepoAccount.SixtyPlusCollectorId = repoAccount.SixtyPlusCollectorId;

            try
            {
                _repoAccountRepository.Update(existingRepoAccount);
                if (originalStatus != repoAccount.Status)
                {
                    var change = new RepoStatusChange()
                    {
                        RepoId = repoAccount.RepoId,
                        ChangedBy = currentUser.FirstName + " " + currentUser.LastName,
                        StatusFrom = originalStatus,
                        StatusTo = repoAccount.Status,
                        ChangedDate = DateTime.Now
                    };
                    await _repoStatusChangeRepository.AddAsync(change);
                }
                await _unitOfWork.CompleteAsync();
                return await _repoAccountRepository.FindByIdAsync(repoAccount.RepoId);
            }
            catch (SqlException ex)
            {
                Log.Error(ex, $"SQL Failure updating  Repo Account: {repoAccount}", repoAccount);
                throw new ServerErrorException();
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Failure updating  Repo Account: {repoAccount}", repoAccount);
                throw new ServerErrorException();
            }
        }
    
        public async Task<RepoAccount> DeleteAsync(int id)
        {
            RepoAccount existingRepoAccount;
            try
            {
                existingRepoAccount = await _repoAccountRepository.FindByIdAsync(id);
            }
            catch(Exception ex)
            {
                Log.Error(ex, $"Error finding an existing repo to delete with account ID: {id}");
                throw new ServerErrorException();
            }

            if (existingRepoAccount == null)
            {
                throw new NotFoundException($" Repo Account with id {id} not found.");
            }

            try
            {
                _repoAccountRepository.Remove(existingRepoAccount);
                await _unitOfWork.CompleteAsync();
                return existingRepoAccount;
            }
            catch (SqlException ex)
            {
                Log.Error(ex, $"SQL Failure deleting  Repo Account with id: {id}", id);
                throw new ServerErrorException();
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Failure deleting  Repo Account with id: {id}", id);
                throw new ServerErrorException();
            }
        }

        public async Task<IReadOnlyCollection<ProcessingItem>> GetItemsForProcessing()
        {
            try
            {
                var watchStatus = await _repoManualStatusRepository.ListWatchStatusesAsync();
                var repoAccountNos = await _repoAccountRepository.GetItemsForProcessing(watchStatus);
                return repoAccountNos;
            }
            catch (Exception ex)
            {
                Log.Error(ex, "Failure getting Repo Account Nos for polling");
                throw new ServerErrorException();
            }
        }

        public async Task<IReadOnlyCollection<RepoAccount>> SearchRepoAccounts(string searchPhrase, int maxAllowedResults)
        {
            try
            {
                var matchedRepoAccounts = await _repoAccountRepository.SearchRepoAccounts(searchPhrase, maxAllowedResults);
                return matchedRepoAccounts;
            }
            catch (MaxItemException ex)
            {
                Log.Error(ex, $"Search Phrase Returned More Items Than Max (${maxAllowedResults}) searchPhrase:{searchPhrase}", searchPhrase);
                throw new MaxItemException(ex.ItemCount);
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Failure Searching For Repo Accounts searchPhrase: {searchPhrase}", searchPhrase);
                throw new ServerErrorException();
            }
        }

        public async Task<RepoAccount> GetNewestOpenAccount(string accountNo)
        {
            IReadOnlyCollection<RepoAccount> repoAccounts;
            try
            {
                repoAccounts = await _repoAccountRepository.FindByAccountNoAsync(accountNo);
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Failure retrieving Repo Account by accountNo with accountNo: {accountNo}");
                throw new ServerErrorException();
            }

            if (repoAccounts == null || !repoAccounts.Any())
            {
                // You can't throw here, it's not an exception case, there simply isn't an account. (404)
                Log.Debug($" Repo Accounts with id {accountNo} not found.");
                return null;
            }

            return SelectFirstOpenAccount(repoAccounts);
        }

        /**
         * Attempts to select the repo account that should be updated. Since we have to go by AccountNo and there
         * may be more than one. Try to return an open account, and log if it detects more than one.
         */
        public RepoAccount SelectFirstOpenAccount(IReadOnlyCollection<RepoAccount> repoAccounts)
        {
            if (repoAccounts.Count == 1)
            {
                return repoAccounts.First();
            }

            RepoAccount openAccount = null;
            foreach (var repoAccount in repoAccounts.OrderBy(x => x.RepoId))
            {
                if (repoAccount.DateClosed == null)
                {
                    if (openAccount != null)
                    {
                        Log.Fatal($"Multiple -OPEN- Repos with AccountNo: {openAccount.AccountNo}, {openAccount.RepoId} / {repoAccount.RepoId}");
                        return openAccount;
                    }
                    openAccount = repoAccount;
                }
            }

            if (openAccount != null)
            {
                return openAccount;
            }

            return repoAccounts.OrderByDescending(x => x.DateClosed).ToList().FirstOrDefault();
        }
    }
}