using System;
using System.IO;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading;
using System.Threading.Tasks;
using System.Xml;
using BililiveRecorder.Core.Api.Danmaku;
using BililiveRecorder.Core.Config.V3;
using Serilog;

#nullable enable
namespace BililiveRecorder.Core.Danmaku
{
    public class BasicDanmakuWriter : IBasicDanmakuWriter
    {
        private static readonly XmlWriterSettings xmlWriterSettings = new XmlWriterSettings
        {
            Async = true,
            Indent = true,
            IndentChars = "  ",
            Encoding = Encoding.UTF8,
            CloseOutput = true,
            WriteEndDocumentOnClose = true,
        };

        private static readonly Regex invalidXMLChars = new Regex(@"(?<![\uD800-\uDBFF])[\uDC00-\uDFFF]|[\uD800-\uDBFF](?![\uDC00-\uDFFF])|[\x00-\x08\x0B\x0C\x0E-\x1F\x7F-\x9F\uFEFF\uFFFE\uFFFF]", RegexOptions.Compiled);
        private static string RemoveInvalidXMLChars(string? text) => string.IsNullOrWhiteSpace(text) ? string.Empty : invalidXMLChars.Replace(text, string.Empty);

        private XmlWriter? xmlWriter = null;
        private DateTimeOffset offset = DateTimeOffset.UtcNow;
        private uint writeCount = 0;
        private RoomConfig? config;

        private readonly SemaphoreSlim semaphoreSlim = new SemaphoreSlim(1, 1);
        private readonly ILogger logger;

        public BasicDanmakuWriter(ILogger logger)
        {
            this.logger = logger?.ForContext<BasicDanmakuWriter>() ?? throw new ArgumentNullException(nameof(logger));
        }

        public void EnableWithPath(string path, IRoom room)
        {
            if (this.disposedValue) return;

            this.semaphoreSlim.Wait();
            try
            {
                if (this.xmlWriter != null)
                {
                    this.xmlWriter.Close();
                    this.xmlWriter.Dispose();
                    this.xmlWriter = null;
                }

                try { Directory.CreateDirectory(Path.GetDirectoryName(path)); } catch (Exception) { }
                var stream = File.Open(path, FileMode.Create, FileAccess.Write, FileShare.Read);

                this.config = room.RoomConfig;

                this.xmlWriter = XmlWriter.Create(stream, xmlWriterSettings);
                WriteStartDocument(this.xmlWriter, room);
                this.offset = DateTimeOffset.UtcNow;
                this.writeCount = 0;
            }
            finally
            {
                this.semaphoreSlim.Release();
            }
        }

        public void Disable()
        {
            if (this.disposedValue) return;

            this.semaphoreSlim.Wait();
            try
            {
                this.DisableCore();
            }
            finally
            {
                this.semaphoreSlim.Release();
            }
        }

        private void DisableCore()
        {
            try
            {
                if (this.xmlWriter != null)
                {
                    this.xmlWriter.Close();
                    this.xmlWriter.Dispose();
                    this.xmlWriter = null;
                }
            }
            catch (Exception ex)
            {
                this.logger.Warning(ex, "关闭弹幕文件时发生错误");
                this.xmlWriter = null;
            }
        }

        public async Task WriteAsync(DanmakuModel danmakuModel)
        {
            if (this.disposedValue) return;
            if (this.config is null) return;

            await this.semaphoreSlim.WaitAsync();
            try
            {
                if (this.xmlWriter != null)
                {
                    var write = true;
                    var recordDanmakuRaw = this.config.RecordDanmakuRaw;
                    switch (danmakuModel.MsgType)
                    {
                        case DanmakuMsgType.Comment:
                            {
                                var type = danmakuModel.RawObject?["info"]?[0]?[1]?.ToObject<int>() ?? 1;
                                var size = danmakuModel.RawObject?["info"]?[0]?[2]?.ToObject<int>() ?? 25;
                                var color = danmakuModel.RawObject?["info"]?[0]?[3]?.ToObject<int>() ?? 0XFFFFFF;
                                var st = danmakuModel.RawObject?["info"]?[0]?[4]?.ToObject<long>() ?? 0L;

                                var ts = Math.Max((DateTimeOffset.UtcNow - this.offset).TotalSeconds, 0d);

                                await this.xmlWriter.WriteStartElementAsync(null, "d", null).ConfigureAwait(false);
                                await this.xmlWriter.WriteAttributeStringAsync(null, "p", null, $"{ts:F3},{type},{size},{color},{st},0,{danmakuModel.UserID},0").ConfigureAwait(false);
                                await this.xmlWriter.WriteAttributeStringAsync(null, "user", null, RemoveInvalidXMLChars(danmakuModel.UserName)).ConfigureAwait(false);
                                if (recordDanmakuRaw)
                                    await this.xmlWriter.WriteAttributeStringAsync(null, "raw", null, danmakuModel.RawObject?["info"]?.ToString(Newtonsoft.Json.Formatting.None)).ConfigureAwait(false);
                                this.xmlWriter.WriteValue(RemoveInvalidXMLChars(danmakuModel.CommentText));
                                await this.xmlWriter.WriteEndElementAsync().ConfigureAwait(false);
                            }
                            break;
                        case DanmakuMsgType.SuperChat:
                            if (this.config.RecordDanmakuSuperChat)
                            {
                                await this.xmlWriter.WriteStartElementAsync(null, "sc", null).ConfigureAwait(false);
                                var ts = Math.Max((DateTimeOffset.UtcNow - this.offset).TotalSeconds, 0d);
                                await this.xmlWriter.WriteAttributeStringAsync(null, "ts", null, ts.ToString("F3")).ConfigureAwait(false);
                                await this.xmlWriter.WriteAttributeStringAsync(null, "user", null, RemoveInvalidXMLChars(danmakuModel.UserName)).ConfigureAwait(false);
                                await this.xmlWriter.WriteAttributeStringAsync(null, "price", null, danmakuModel.Price.ToString()).ConfigureAwait(false);
                                await this.xmlWriter.WriteAttributeStringAsync(null, "time", null, danmakuModel.SCKeepTime.ToString()).ConfigureAwait(false);
                                if (recordDanmakuRaw)
                                    await this.xmlWriter.WriteAttributeStringAsync(null, "raw", null, danmakuModel.RawObject?["data"]?.ToString(Newtonsoft.Json.Formatting.None)).ConfigureAwait(false);
                                this.xmlWriter.WriteValue(RemoveInvalidXMLChars(danmakuModel.CommentText));
                                await this.xmlWriter.WriteEndElementAsync().ConfigureAwait(false);
                            }
                            break;
                        case DanmakuMsgType.GiftSend:
                            if (this.config.RecordDanmakuGift)
                            {
                                await this.xmlWriter.WriteStartElementAsync(null, "gift", null).ConfigureAwait(false);
                                var ts = Math.Max((DateTimeOffset.UtcNow - this.offset).TotalSeconds, 0d);
                                await this.xmlWriter.WriteAttributeStringAsync(null, "ts", null, ts.ToString("F3")).ConfigureAwait(false);
                                await this.xmlWriter.WriteAttributeStringAsync(null, "user", null, RemoveInvalidXMLChars(danmakuModel.UserName)).ConfigureAwait(false);
                                await this.xmlWriter.WriteAttributeStringAsync(null, "giftname", null, RemoveInvalidXMLChars(danmakuModel.GiftName)).ConfigureAwait(false);
                                await this.xmlWriter.WriteAttributeStringAsync(null, "giftcount", null, danmakuModel.GiftCount.ToString()).ConfigureAwait(false);
                                if (recordDanmakuRaw)
                                    await this.xmlWriter.WriteAttributeStringAsync(null, "raw", null, danmakuModel.RawObject?["data"]?.ToString(Newtonsoft.Json.Formatting.None)).ConfigureAwait(false);
                                await this.xmlWriter.WriteEndElementAsync().ConfigureAwait(false);
                            }
                            break;
                        case DanmakuMsgType.GuardBuy:
                            if (this.config.RecordDanmakuGuard)
                            {
                                await this.xmlWriter.WriteStartElementAsync(null, "guard", null).ConfigureAwait(false);
                                var ts = Math.Max((DateTimeOffset.UtcNow - this.offset).TotalSeconds, 0d);
                                await this.xmlWriter.WriteAttributeStringAsync(null, "ts", null, ts.ToString("F3")).ConfigureAwait(false);
                                await this.xmlWriter.WriteAttributeStringAsync(null, "user", null, RemoveInvalidXMLChars(danmakuModel.UserName)).ConfigureAwait(false);
                                await this.xmlWriter.WriteAttributeStringAsync(null, "level", null, danmakuModel.UserGuardLevel.ToString()).ConfigureAwait(false); ;
                                await this.xmlWriter.WriteAttributeStringAsync(null, "count", null, danmakuModel.GiftCount.ToString()).ConfigureAwait(false);
                                if (recordDanmakuRaw)
                                    await this.xmlWriter.WriteAttributeStringAsync(null, "raw", null, danmakuModel.RawObject?["data"]?.ToString(Newtonsoft.Json.Formatting.None)).ConfigureAwait(false);
                                await this.xmlWriter.WriteEndElementAsync().ConfigureAwait(false);
                            }
                            break;
                        default:
                            write = false;
                            break;
                    }

                    if (write && this.writeCount++ >= this.config.RecordDanmakuFlushInterval)
                    {
                        await this.xmlWriter.FlushAsync();
                        this.writeCount = 0;
                    }
                }
            }
            catch (Exception ex)
            {
                this.logger.Warning(ex, "写入弹幕时发生错误");
                this.DisableCore();
            }
            finally
            {
                this.semaphoreSlim.Release();
            }
        }

        private static void WriteStartDocument(XmlWriter writer, IRoom room)
        {
            writer.WriteStartDocument();
            writer.WriteProcessingInstruction("xml-stylesheet", "type=\"text/xsl\" href=\"#s\"");
            writer.WriteStartElement("i");
            writer.WriteComment("\nB站录播姬 " + GitVersionInformation.FullSemVer + "\n本文件的弹幕信息兼容B站主站视频弹幕XML格式\n本XML自带样式可以在浏览器里打开（推荐使用Chrome）\n\nsc 为SuperChat\ngift为礼物\nguard为上船\n\nattribute \"raw\" 为原始数据\n");
            writer.WriteElementString("chatserver", "chat.bilibili.com");
            writer.WriteElementString("chatid", "0");
            writer.WriteElementString("mission", "0");
            writer.WriteElementString("maxlimit", "1000");
            writer.WriteElementString("state", "0");
            writer.WriteElementString("real_name", "0");
            writer.WriteElementString("source", "0");

            writer.WriteStartElement("BililiveRecorder");
            writer.WriteAttributeString("version", GitVersionInformation.FullSemVer);
            writer.WriteEndElement();

            writer.WriteStartElement("BililiveRecorderRecordInfo");
            writer.WriteAttributeString("roomid", room.RoomConfig.RoomId.ToString());
            writer.WriteAttributeString("shortid", room.ShortId.ToString());
            writer.WriteAttributeString("name", RemoveInvalidXMLChars(room.Name));
            writer.WriteAttributeString("title", RemoveInvalidXMLChars(room.Title));
            writer.WriteAttributeString("areanameparent", RemoveInvalidXMLChars(room.AreaNameParent));
            writer.WriteAttributeString("areanamechild", RemoveInvalidXMLChars(room.AreaNameChild));
            writer.WriteAttributeString("start_time", DateTimeOffset.Now.ToString("O"));
            writer.WriteEndElement();

            // see BililiveRecorder.ToolBox\Tool\DanmakuMerger\DanmakuMergerHandler.cs
            const string style = @"<z:stylesheet version=""1.0"" id=""s"" xml:id=""s"" xmlns:z=""http://www.w3.org/1999/XSL/Transform""><z:output method=""html""/><z:template match=""/""><html><meta name=""viewport"" content=""width=device-width""/><title>B站录播姬弹幕文件 - <z:value-of select=""/i/BililiveRecorderRecordInfo/@name""/></title><style>body{margin:0}h1,h2,p,table{margin-left:5px}table{border-spacing:0}td,th{border:1px solid grey;padding:1px}th{position:sticky;top:0;background:#4098de}tr:hover{background:#d9f4ff}div{overflow:auto;max-height:80vh;max-width:100vw;width:fit-content}</style><h1>B站录播姬弹幕XML文件</h1><p>本文件的弹幕信息兼容B站主站视频弹幕XML格式，可以使用现有的转换工具把文件中的弹幕转为ass字幕文件</p><table><tr><td>录播姬版本</td><td><z:value-of select=""/i/BililiveRecorder/@version""/></td></tr><tr><td>房间号</td><td><z:value-of select=""/i/BililiveRecorderRecordInfo/@roomid""/></td></tr><tr><td>主播名</td><td><z:value-of select=""/i/BililiveRecorderRecordInfo/@name""/></td></tr><tr><td>录制开始时间</td><td><z:value-of select=""/i/BililiveRecorderRecordInfo/@start_time""/></td></tr><tr><td><a href=""#d"">弹幕</a></td><td>共 <z:value-of select=""count(/i/d)""/> 条记录</td></tr><tr><td><a href=""#guard"">上船</a></td><td>共 <z:value-of select=""count(/i/guard)""/> 条记录</td></tr><tr><td><a href=""#sc"">SC</a></td><td>共 <z:value-of select=""count(/i/sc)""/> 条记录</td></tr><tr><td><a href=""#gift"">礼物</a></td><td>共 <z:value-of select=""count(/i/gift)""/> 条记录</td></tr></table><h2 id=""d"">弹幕</h2><div><table><tr><th>用户名</th><th>弹幕</th><th>参数</th></tr><z:for-each select=""/i/d""><tr><td><z:value-of select=""@user""/></td><td><z:value-of select="".""/></td><td><z:value-of select=""@p""/></td></tr></z:for-each></table></div><h2 id=""guard"">舰长购买</h2><div><table><tr><th>用户名</th><th>舰长等级</th><th>购买数量</th><th>出现时间</th></tr><z:for-each select=""/i/guard""><tr><td><z:value-of select=""@user""/></td><td><z:value-of select=""@level""/></td><td><z:value-of select=""@count""/></td><td><z:value-of select=""@ts""/></td></tr></z:for-each></table></div><h2 id=""sc"">SuperChat 醒目留言</h2><div><table><tr><th>用户名</th><th>内容</th><th>显示时长</th><th>价格</th><th>出现时间</th></tr><z:for-each select=""/i/sc""><tr><td><z:value-of select=""@user""/></td><td><z:value-of select="".""/></td><td><z:value-of select=""@time""/></td><td><z:value-of select=""@price""/></td><td><z:value-of select=""@ts""/></td></tr></z:for-each></table></div><h2 id=""gift"">礼物</h2><div><table><tr><th>用户名</th><th>礼物名</th><th>礼物数量</th><th>出现时间</th></tr><z:for-each select=""/i/gift""><tr><td><z:value-of select=""@user""/></td><td><z:value-of select=""@giftname""/></td><td><z:value-of select=""@giftcount""/></td><td><z:value-of select=""@ts""/></td></tr></z:for-each></table></div></html></z:template></z:stylesheet>";

            writer.WriteStartElement("BililiveRecorderXmlStyle");
            writer.WriteRaw(style);
            writer.WriteEndElement();
            writer.Flush();
        }

        private bool disposedValue;

        protected virtual void Dispose(bool disposing)
        {
            if (!this.disposedValue)
            {
                if (disposing)
                {
                    // dispose managed state (managed objects)
                    this.semaphoreSlim.Dispose();
                    this.xmlWriter?.Close();
                    this.xmlWriter?.Dispose();
                    this.xmlWriter = null;
                }

                // free unmanaged resources (unmanaged objects) and override finalizer
                // set large fields to null
                this.disposedValue = true;
            }
        }

        public void Dispose()
        {
            // Do not change this code. Put cleanup code in 'Dispose(bool disposing)' method
            this.Dispose(disposing: true);
            GC.SuppressFinalize(this);
        }
    }
}