/*
 *
 * (c) Copyright Ascensio System Limited 2010-2018
 *
 * This program is freeware. You can redistribute it and/or modify it under the terms of the GNU 
 * General Public License (GPL) version 3 as published by the Free Software Foundation (https://www.gnu.org/copyleft/gpl.html). 
 * In accordance with Section 7(a) of the GNU GPL its Section 15 shall be amended to the effect that 
 * Ascensio System SIA expressly excludes the warranty of non-infringement of any third-party rights.
 *
 * THIS PROGRAM IS DISTRIBUTED WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED WARRANTY OF MERCHANTABILITY OR
 * FITNESS FOR A PARTICULAR PURPOSE. For more details, see GNU GPL at https://www.gnu.org/copyleft/gpl.html
 *
 * You can contact Ascensio System SIA by email at sales@onlyoffice.com
 *
 * The interactive user interfaces in modified source and object code versions of ONLYOFFICE must display 
 * Appropriate Legal Notices, as required under Section 5 of the GNU GPL version 3.
 *
 * Pursuant to Section 7 § 3(b) of the GNU GPL you must retain the original ONLYOFFICE logo which contains 
 * relevant author attributions when distributing the software. If the display of the logo in its graphic 
 * form is not reasonably feasible for technical reasons, you must include the words "Powered by ONLYOFFICE" 
 * in every copy of the program you distribute. 
 * Pursuant to Section 7 § 3(e) we decline to grant you any rights under trademark law for use of our trademarks.
 *
*/


using ASC.Common;
using ASC.Common.Logging;
using ASC.Core;
using ASC.Core.Common.Configuration;
using ASC.Core.Notify.Signalr;
using ASC.CRM.Core;
using ASC.CRM.Core.Dao;
using ASC.CRM.Core.Entities;
using ASC.VoipService;
using ASC.VoipService.Twilio;
using ASC.Web.Studio.Utility;
using Autofac;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Filters;
using Microsoft.Extensions.Options;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Text;
using System.Web;
using System.Web.Http;
using Twilio.AspNet.Common;
using Twilio.AspNet.Core;
using Twilio.TwiML;

namespace ASC.Web.CRM.Classes
{

    [ServiceFilter(typeof(ValidateRequestFilter))]
    public class TwilioController : ApiController
    {
        public TwilioController(IOptionsMonitor<ILog> logger,
                                DaoFactory daoFactory,
                                VoipEngine voipEngine,
                                TenantManager tenantManager,
                                SecurityContext securityContext)
        {
            TenantManager = tenantManager;
            Log = logger.Get("ASC");
            DaoFactory = daoFactory;
            VoipEngine = voipEngine;
            SecurityContext = securityContext;
        }

        public SecurityContext SecurityContext { get; }
        public TenantManager TenantManager { get; }
        public VoipEngine VoipEngine { get; }
        public DaoFactory DaoFactory { get; }

        private readonly ILog Log;
        private static readonly object LockObj = new object();

        [System.Web.Http.HttpPost]
        public HttpResponseMessage Index(TwilioVoiceRequest request, [FromUri]Guid? callerId = null, [FromUri]int contactId = 0)
        {
            try
            {
                lock (LockObj)
                {
                    request.AddAdditionalFields(callerId, contactId);

                    var response = request.IsInbound ? Inbound(request, DaoFactory) : Outbound(request, DaoFactory);

                    return GetHttpResponse(response);

                }
            }
            catch (Exception e)
            {
                Log.Error(e);
                throw;
            }
        }

        [System.Web.Http.HttpPost]
        public HttpResponseMessage Client(TwilioVoiceRequest request, [FromUri]Guid callerId)
        {
            try
            {
                request.AddAdditionalFields(callerId);

                VoipEngine.SaveOrUpdateCall(CallFromTwilioRequest(request));

                return GetHttpResponse(new VoiceResponse());
            }
            catch (Exception e)
            {
                Log.Error(e);
                throw;
            }
        }

        [System.Web.Http.HttpPost]
        public HttpResponseMessage Dial(TwilioVoiceRequest request, [FromUri]Guid callerId, [FromUri]int contactId = 0, [FromUri]string reject = null)
        {
            try
            {
                request.AddAdditionalFields(callerId, contactId, reject);

                var call = CallFromTwilioRequest(request);
                call = VoipEngine.SaveOrUpdateCall(call);

                var parentCall = DaoFactory.GetVoipDao().GetCall(call.ParentID);

                if (!string.IsNullOrEmpty(request.RecordingSid))
                {
                    if (parentCall.VoipRecord == null || string.IsNullOrEmpty(parentCall.VoipRecord.Id))
                    {
                        parentCall.VoipRecord = new VoipRecord { Id = request.RecordingSid };
                    }

                    DaoFactory.GetVoipDao().SaveOrUpdateCall(parentCall);
                }

                VoipEngine.SaveAdditionalInfo(parentCall.Id);

                return GetHttpResponse(request.Dial());

            }
            catch (Exception e)
            {
                Log.Error(e);
                throw;
            }
        }

        [System.Web.Http.HttpPost]
        public HttpResponseMessage Enqueue(TwilioVoiceRequest request, [FromUri]Guid? callerId = null, [FromUri]int contactId = 0)
        {
            try
            {
                request.AddAdditionalFields(callerId, contactId);

                if (request.QueueResult != "bridged" && request.QueueResult != "redirected")
                {
                    MissCall(request, VoipEngine);
                }

                return GetHttpResponse(request.Enqueue(request.QueueResult));

            }
            catch (Exception e)
            {
                Log.Error(e);
                throw;
            }
        }

        [System.Web.Http.HttpPost]
        public HttpResponseMessage Queue(TwilioVoiceRequest request, [FromUri]Guid? callerId = null, [FromUri]int contactId = 0)
        {
            try
            {
                request.AddAdditionalFields(callerId, contactId);
                return GetHttpResponse(request.Queue());
            }
            catch (Exception e)
            {
                Log.Error(e);
                throw;
            }
        }

        [System.Web.Http.HttpPost]
        public HttpResponseMessage Dequeue(TwilioVoiceRequest request, [FromUri]Guid? callerId = null, [FromUri]int contactId = 0, [FromUri]string reject = "")
        {
            try
            {
                request.AddAdditionalFields(callerId, contactId, reject);

                if (Convert.ToBoolean(request.Reject))
                {
                    MissCall(request, VoipEngine);
                    return GetHttpResponse(request.Leave());
                }

                VoipEngine.AnswerCall(CallFromTwilioRequest(request));

                return GetHttpResponse(request.Dequeue());

            }
            catch (Exception e)
            {
                Log.Error(e);
                throw;
            }
        }

        [System.Web.Http.HttpPost]
        public HttpResponseMessage Wait(TwilioVoiceRequest request, [FromUri]Guid? callerId = null, [FromUri]int contactId = 0, [FromUri]string redirectTo = null)
        {
            try
            {

                request.AddAdditionalFields(callerId, contactId, redirectTo: redirectTo);
                if (Convert.ToInt32(request.QueueTime) == 0)
                {
                    var history = CallFromTwilioRequest(request);

                    history.ParentID = history.Id;

                    VoipEngine.SaveOrUpdateCall(history);

                    var to = request.RedirectTo;
                    if (string.IsNullOrEmpty(to))
                    {
                        request.GetSignalRHelper()
                            .Enqueue(request.CallSid, callerId.HasValue ? callerId.Value.ToString() : "");
                    }
                    else
                    {
                        request.GetSignalRHelper().Incoming(request.CallSid, to);
                    }
                }

                return GetHttpResponse(request.Wait());

            }
            catch (Exception e)
            {
                Log.Error(e);
                throw;
            }
        }

        [System.Web.Http.HttpPost]
        public HttpResponseMessage GatherQueue(TwilioVoiceRequest request, [FromUri]Guid? callerId = null, [FromUri]int contactId = 0)
        {
            try
            {
                request.AddAdditionalFields(callerId, contactId);
                return GetHttpResponse(request.GatherQueue());
            }
            catch (Exception e)
            {
                Log.Error(e);
                throw;
            }
        }

        [System.Web.Http.HttpPost]
        public HttpResponseMessage Redirect(TwilioVoiceRequest request, [FromUri]string redirectTo, [FromUri]Guid? callerId = null)
        {
            try
            {
                request.AddAdditionalFields(callerId, redirectTo: redirectTo);
                return GetHttpResponse(request.Redirect());
            }
            catch (Exception e)
            {
                Log.Error(e);
                throw;
            }
        }

        [System.Web.Http.HttpPost]
        public HttpResponseMessage VoiceMail(TwilioVoiceRequest request, [FromUri]Guid? callerId = null, [FromUri]int contactId = 0)
        {
            try
            {
                request.AddAdditionalFields(callerId, contactId);

                MissCall(request, VoipEngine);

                return GetHttpResponse(request.VoiceMail());

            }
            catch (Exception e)
            {
                Log.Error(e);
                throw;
            }
        }

        private VoiceResponse Inbound(TwilioVoiceRequest request, DaoFactory daoFactory)
        {
            SecurityContext.AuthenticateMe(TenantManager.GetCurrentTenant().OwnerId);
            var call = SaveCall(request, VoipCallStatus.Incoming, daoFactory);

            return request.Inbound(call, daoFactory);
        }

        private VoiceResponse Outbound(TwilioVoiceRequest request, DaoFactory daoFactory)
        {
            SaveCall(request, VoipCallStatus.Outcoming, daoFactory);

            var history = CallFromTwilioRequest(request);
            history.ParentID = history.Id;

            VoipEngine.SaveOrUpdateCall(history);

            return request.Outbound();
        }

        private VoipCall SaveCall(TwilioVoiceRequest request, VoipCallStatus status, DaoFactory daoFactory)
        {
            var call = CallFromTwilioRequest(request);
            call.Status = status;

            return DaoFactory.GetVoipDao().SaveOrUpdateCall(call);
        }

        private void MissCall(TwilioVoiceRequest request, VoipEngine voipEngine)
        {
            var voipCall = CallFromTwilioRequest(request);
            voipCall.Status = VoipCallStatus.Missed;

            if (!string.IsNullOrEmpty(request.RecordingSid))
            {
                if (voipCall.VoipRecord == null || string.IsNullOrEmpty(voipCall.VoipRecord.Id))
                {
                    voipCall.VoipRecord = new VoipRecord { Id = request.RecordingSid };
                }
            }

            voipCall = voipEngine.SaveOrUpdateCall(voipCall);
            request.GetSignalRHelper().MissCall(request.CallSid, voipCall.AnsweredBy.ToString());
            voipEngine.SaveAdditionalInfo(voipCall.Id);
        }

        private VoipCall CallFromTwilioRequest(TwilioVoiceRequest request)
        {
            if (!string.IsNullOrEmpty(request.DialCallSid))
            {
                return new VoipCall
                {
                    Id = request.DialCallSid,
                    ParentID = request.CallSid,
                    From = request.From,
                    To = request.To,
                    AnsweredBy = request.CallerId,
                    EndDialDate = DateTime.UtcNow
                };
            }

            return new VoipCall
            {
                Id = request.CallSid,
                ParentID = request.ParentCallSid,
                From = request.From,
                To = request.To,
                AnsweredBy = request.CallerId,
                Date = DateTime.UtcNow,
                ContactId = request.ContactId
            };
        }


        private HttpResponseMessage GetHttpResponse(VoiceResponse response)
        {
            Log.Info(response);
            return new HttpResponseMessage { Content = new StringContent(response.ToString(), Encoding.UTF8, "application/xml") };
        }
    }

    public class TwilioVoiceRequest : VoiceRequest
    {
        public TwilioVoiceRequest(TwilioResponseHelper twilioResponseHelper,
                                  CommonLinkUtility commonLinkUtility,
                                  DaoFactory daoFactory,
                                  SecurityContext securityContext,
                                  CRMSecurity cRMSecurity,
                                  VoipEngine voipEngine,
                                  SignalrServiceClient signalrServiceClient)
        {

            DaoFactory = daoFactory;
            CommonLinkUtility = commonLinkUtility;
            TwilioResponseHelper = twilioResponseHelper;
            SecurityContext = securityContext;
            CRMSecurity = cRMSecurity;
            VoipEngine = voipEngine;
            SignalrServiceClient = signalrServiceClient;

        }

        public SignalrServiceClient SignalrServiceClient { get; }

        public VoipEngine VoipEngine { get; }
        public CRMSecurity CRMSecurity { get; }
        public TwilioResponseHelper TwilioResponseHelper { get; }
        public CommonLinkUtility CommonLinkUtility { get; }
        public DaoFactory DaoFactory { get; }
        public SecurityContext SecurityContext { get; }
        public Guid CallerId { get; set; }
        public int ContactId { get; set; }
        public string ParentCallSid { get; set; }
        public string QueueResult { get; set; }
        public string QueueTime { get; set; }
        public string QueueSid { get; set; }
        public bool Reject { get; set; }
        public string RedirectTo { get; set; }
        public string CurrentQueueSize { get; set; }

        public bool Pause { get { return GetSettings().Pause; } }

        private TwilioResponseHelper GetTwilioResponseHelper()
        {
            return TwilioResponseHelper;
        }

        private VoipSettings settings;
        private VoipSettings GetSettings()
        {
            return settings ?? (settings = DaoFactory.GetVoipDao().GetNumber(IsInbound ? To : From).Settings);
        }

        private SignalRHelper signalRHelper;
        public SignalRHelper GetSignalRHelper()
        {
            return signalRHelper ?? (signalRHelper = new SignalRHelper(IsInbound ? To : From, SignalrServiceClient));
        }

        public bool IsInbound
        {
            get { return Direction == "inbound"; }
        }

        public void AddAdditionalFields(Guid? callerId, int contactId = 0, string reject = null, string redirectTo = null)
        {
            if (callerId.HasValue && !callerId.Value.Equals(ASC.Core.Configuration.Constants.Guest.ID))
            {
                CallerId = callerId.Value;
                SecurityContext.AuthenticateMe(CallerId);
            }
            if (contactId != 0)
            {
                ContactId = contactId;
            }

            if (!string.IsNullOrEmpty(reject))
            {
                Reject = Convert.ToBoolean(reject);
            }

            if (!string.IsNullOrEmpty(redirectTo))
            {
                RedirectTo = redirectTo;
            }
        }

        internal VoiceResponse Inbound(VoipCall call, DaoFactory daoFactory)
        {
            var contactPhone = call.Status == VoipCallStatus.Incoming || call.Status == VoipCallStatus.Answered
                ? call.From
                : call.To;

            Contact contact;
            var contacts = VoipEngine.GetContacts(contactPhone, daoFactory);
            var managers = contacts.SelectMany(CRMSecurity.GetAccessSubjectGuidsTo).ToList();
            var agent = GetSignalRHelper().GetAgent(managers);

            if (agent != null && agent.Item1 != null)
            {
                var agentId = agent.Item1.Id;
                SecurityContext.AuthenticateMe(agentId);
                call.AnsweredBy = agentId;

                contact = contacts.FirstOrDefault(CRMSecurity.CanAccessTo);

                DaoFactory.GetVoipDao().SaveOrUpdateCall(call);
            }
            else
            {
                contact = contacts.FirstOrDefault();
            }

            if (contact == null)
            {
                contact = VoipEngine.CreateContact(call.From.TrimStart('+'));
                call.ContactId = contact.ID;
                DaoFactory.GetVoipDao().SaveOrUpdateCall(call);
            }

            return GetTwilioResponseHelper().Inbound(agent);
        }
        internal VoiceResponse Outbound() { return GetTwilioResponseHelper().Outbound(); }
        internal VoiceResponse Dial() { return GetTwilioResponseHelper().Dial(); }
        internal VoiceResponse Enqueue(string queueResult) { return GetTwilioResponseHelper().Enqueue(queueResult); }
        internal VoiceResponse Queue() { return GetTwilioResponseHelper().Queue(); }
        internal VoiceResponse Leave() { return GetTwilioResponseHelper().Leave(); }
        internal VoiceResponse Dequeue() { return GetTwilioResponseHelper().Dequeue(); }
        internal VoiceResponse Wait() { return GetTwilioResponseHelper().Wait(QueueSid, QueueTime, QueueTime); }
        internal VoiceResponse GatherQueue() { return GetTwilioResponseHelper().GatherQueue(Digits, To.Substring(1), new List<Agent>()); }
        internal VoiceResponse Redirect() { return GetTwilioResponseHelper().Redirect(RedirectTo); }
        internal VoiceResponse VoiceMail() { return GetTwilioResponseHelper().VoiceMail(); }
    }

    public class ValidateRequestFilter : ActionFilterAttribute
    {
        public ValidateRequestFilter(ConsumerFactory consumerFactory, IHttpContextAccessor httpContextAccessor)
        {
            ConsumerFactory = consumerFactory;
            HttpContext = httpContextAccessor?.HttpContext;
        }

        public HttpContext HttpContext { get; }
        public ConsumerFactory ConsumerFactory { get; }

        public override void OnActionExecuting(ActionExecutingContext filterContext)
        {
            if (!new RequestValidationHelper().IsValidRequest(filterContext.HttpContext, ConsumerFactory.Get<Web.Core.Sms.TwilioProvider>()["twilioAuthToken"], HttpContext.Request.GetUrlRewriter().AbsoluteUri))
                filterContext.Result = new HttpStatusCodeResult(HttpStatusCode.Forbidden);

            base.OnActionExecuting(filterContext);

        }
    }

    public static class TwilioControllerExtension
    {
        public static DIHelper AddTwilioControllerService(this DIHelper services)
        {
            services.TryAddScoped<TwilioController>();

            return services.AddDaoFactoryService()
                           .AddVoipEngineService()
                           .AddTenantManagerService()
                           .AddSecurityContextService();

        }
    }

    public static class TwilioVoiceRequestExtension
    {
        public static DIHelper AddTwilioVoiceRequestService(this DIHelper services)
        {
            services.TryAddScoped<TwilioVoiceRequest>();

            return services.AddCommonLinkUtilityService()
                            .AddDaoFactoryService()
                            .AddSecurityContextService()
                            .AddCRMSecurityService()
                            .AddSignalrServiceClient();

        }
    }


    public static class ValidateRequestFilterExtension
    {
        public static DIHelper AddValidateRequestAttributeService(this DIHelper services)
        {
            services.TryAddScoped<ValidateRequestFilter>();

            return services.AddConsumerFactoryService();

        }
    }

}