using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text.RegularExpressions;

using BirdsiteLive.ActivityPub;
using BirdsiteLive.ActivityPub.Converters;
using BirdsiteLive.ActivityPub.Models;
using BirdsiteLive.Common.Settings;
using BirdsiteLive.Domain.Repository;
using BirdsiteLive.Domain.Statistics;
using BirdsiteLive.Domain.Tools;
using BirdsiteLive.Twitter.Models;

using Tweetinvi.Models;
using Tweetinvi.Models.Entities;

namespace BirdsiteLive.Domain
{
    public interface IStatusService
    {
        Note GetStatus(string username, ExtractedTweet tweet);
    }

    public class StatusService : IStatusService
    {
        private readonly InstanceSettings _instanceSettings;
        private readonly IStatusExtractor _statusExtractor;
        private readonly IExtractionStatisticsHandler _statisticsHandler;
        private readonly IPublicationRepository _publicationRepository;

        #region Ctor
        public StatusService(
            InstanceSettings instanceSettings,
            IStatusExtractor statusExtractor,
            IExtractionStatisticsHandler statisticsHandler,
            IPublicationRepository publicationRepository
        )
        {
            _instanceSettings = instanceSettings;
            _statusExtractor = statusExtractor;
            _statisticsHandler = statisticsHandler;
            _publicationRepository = publicationRepository;
        }
        #endregion

        public Note GetStatus(string username, ExtractedTweet tweet)
        {
            var actorUrl = UrlFactory.GetActorUrl(_instanceSettings.Domain, username);
            var noteUrl = UrlFactory.GetNoteUrl(
                _instanceSettings.Domain,
                username,
                tweet.Id.ToString()
            );

            var to = $"{actorUrl}/followers";

            var isUnlisted = _publicationRepository.IsUnlisted(username);
            var cc = new string[0];
            if (isUnlisted)
                cc = new[] { "https://www.w3.org/ns/activitystreams#Public" };

            string summary = null;
            var sensitive = _publicationRepository.IsSensitive(username);
            if (sensitive || tweet.IsSensitive)
                summary = "Sensitive Content";

            var extractedTags = _statusExtractor.Extract(tweet.MessageContent);
            _statisticsHandler.ExtractedStatus(extractedTags.tags.Count(x => x.type == "Mention"));

            // Replace RT by a link
            var content = extractedTags.content;
            if (content.Contains("{RT}") && tweet.IsRetweet)
            {
                if (!string.IsNullOrWhiteSpace(tweet.RetweetUrl))
                    content = content.Replace(
                        "{RT}",
                        $@"<a href=""{tweet.RetweetUrl}"" rel=""nofollow noopener noreferrer"" target=""_blank"">RT</a>"
                    );
                else
                    content = content.Replace("{RT}", "RT");
            }

            string inReplyTo = null;
            if (tweet.InReplyToStatusId != default)
                inReplyTo =
                    $"https://{_instanceSettings.Domain}/users/{tweet.InReplyToAccount.ToLowerInvariant()}/statuses/{tweet.InReplyToStatusId}";

            if (tweet.QuoteTweetUrl != null)
                content +=
                    $@"<span class=""quote-inline""><br><br>RT: <a href=""{tweet.QuoteTweetUrl}"">{tweet.QuoteTweetUrl}</a></span>";

            var note = new Note
            {
                id = noteUrl,
                published = tweet.CreatedAt.ToString("s") + "Z",
                url = noteUrl,
                attributedTo = actorUrl,
                inReplyTo = inReplyTo,
                to = new[] { to },
                cc = cc,
                sensitive = tweet.IsSensitive || sensitive,
                summary = summary,
                content = $"<p>{content}</p>",
                attachment = Convert(tweet.Media),
                tag = extractedTags.tags,
                quoteUrl = tweet.QuoteTweetUrl
            };

            return note;
        }

        private Attachment[] Convert(ExtractedMedia[] media)
        {
            if (media == null)
                return new Attachment[0];
            return media
                .Select(x =>
                {
                    return new Attachment
                    {
                        type = "Document",
                        url = x.Url,
                        mediaType = x.MediaType
                    };
                })
                .ToArray();
        }
    }
}