using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using Wino.Core.Domain.Entities.Shared;
using Wino.Core.Domain.Interfaces;
using Wino.Core.Integration.Processors;
using Wino.Core.Synchronizers.Mail;

namespace Wino.Core.Services
{
    public class SynchronizerFactory : ISynchronizerFactory
    {
        private bool isInitialized = false;

        private readonly IAccountService _accountService;
        private readonly IImapSynchronizationStrategyProvider _imapSynchronizationStrategyProvider;
        private readonly IApplicationConfiguration _applicationConfiguration;
        private readonly IOutlookChangeProcessor _outlookChangeProcessor;
        private readonly IGmailChangeProcessor _gmailChangeProcessor;
        private readonly IImapChangeProcessor _imapChangeProcessor;
        private readonly IOutlookAuthenticator _outlookAuthenticator;
        private readonly IGmailAuthenticator _gmailAuthenticator;

        private readonly List<IWinoSynchronizerBase> synchronizerCache = new();

        public SynchronizerFactory(IOutlookChangeProcessor outlookChangeProcessor,
                                   IGmailChangeProcessor gmailChangeProcessor,
                                   IImapChangeProcessor imapChangeProcessor,
                                   IOutlookAuthenticator outlookAuthenticator,
                                   IGmailAuthenticator gmailAuthenticator,
                                   IAccountService accountService,
                                   IImapSynchronizationStrategyProvider imapSynchronizationStrategyProvider,
                                   IApplicationConfiguration applicationConfiguration)
        {
            _outlookChangeProcessor = outlookChangeProcessor;
            _gmailChangeProcessor = gmailChangeProcessor;
            _imapChangeProcessor = imapChangeProcessor;
            _outlookAuthenticator = outlookAuthenticator;
            _gmailAuthenticator = gmailAuthenticator;
            _accountService = accountService;
            _imapSynchronizationStrategyProvider = imapSynchronizationStrategyProvider;
            _applicationConfiguration = applicationConfiguration;
        }

        public async Task<IWinoSynchronizerBase> GetAccountSynchronizerAsync(Guid accountId)
        {
            var synchronizer = synchronizerCache.Find(a => a.Account.Id == accountId);

            if (synchronizer == null)
            {
                var account = await _accountService.GetAccountAsync(accountId);

                if (account != null)
                {
                    synchronizer = CreateNewSynchronizer(account);


                    return await GetAccountSynchronizerAsync(accountId);
                }
            }

            return synchronizer;
        }

        private IWinoSynchronizerBase CreateIntegratorWithDefaultProcessor(MailAccount mailAccount)
        {
            var providerType = mailAccount.ProviderType;

            switch (providerType)
            {
                case Domain.Enums.MailProviderType.Outlook:
                    return new OutlookSynchronizer(mailAccount, _outlookAuthenticator, _outlookChangeProcessor);
                case Domain.Enums.MailProviderType.Gmail:
                    return new GmailSynchronizer(mailAccount, _gmailAuthenticator, _gmailChangeProcessor);
                case Domain.Enums.MailProviderType.IMAP4:
                    return new ImapSynchronizer(mailAccount, _imapChangeProcessor, _imapSynchronizationStrategyProvider, _applicationConfiguration);
                default:
                    break;
            }

            return null;
        }

        public IWinoSynchronizerBase CreateNewSynchronizer(MailAccount account)
        {
            var synchronizer = CreateIntegratorWithDefaultProcessor(account);

            if (synchronizer is IImapSynchronizer imapSynchronizer)
            {
                // Start the idle client for IMAP synchronizer.
                _ = imapSynchronizer.StartIdleClientAsync();
            }

            synchronizerCache.Add(synchronizer);

            return synchronizer;
        }

        public async Task InitializeAsync()
        {
            if (isInitialized) return;

            var accounts = await _accountService.GetAccountsAsync();

            foreach (var account in accounts)
            {
                CreateNewSynchronizer(account);
            }

            isInitialized = true;
        }

        public async Task DeleteSynchronizerAsync(Guid accountId)
        {
            var synchronizer = synchronizerCache.Find(a => a.Account.Id == accountId);

            if (synchronizer != null)
            {
                // Stop the current synchronization.
                await synchronizer.KillSynchronizerAsync();

                synchronizerCache.Remove(synchronizer);
            }
        }
    }
}