IM_NEW/MessageService.Domain/Entities/Message.cs

using IM.Commons.IntegrationEvents;
using IM.DomainCommons;
using MessageService.Domain.Enums;
using MessageService.Domain.Events;
using MessageService.Domain.KeyObjects;
using MessageService.Domain.Tools;
using System.Text.Json;

namespace MessageService.Domain.Entities
{
    public class Message : AggregateRootEntity
    {
        /// <summary>
        /// 聊天类型
        /// （0：私聊,1：群聊）
        /// </summary>
        public ChatType ChatType { get; private set; }

        /// <summary>
        /// 消息类型
        /// (0:文本,1：图片,2：语音,3：视频,4：文件，5：语音聊天,6：视频聊天)
        /// </summary>
        public MessageType MsgType { get; private set; }
        public Guid ClientMsgId { get; private set; }

        /// <summary>
        /// 消息内容	
        /// </summary>
        public MessageContent Content { get; private set; } = null!;

        /// <summary>
        /// 发送者	
        /// </summary>
        public Guid SenderId { get; private set; }

        /// <summary>
        /// 接收者（私聊为用户ID，群聊为群聊ID）	
        /// </summary>
        public Guid TargetId { get; private set; }

        /// <summary>
        /// 消息状态(0:已发送,1:已撤回)	
        /// </summary>
        public MessageState State { get; private set; } = MessageState.Sent;

        /// <summary>
        /// 消息推送唯一标识符
        /// </summary>
        public string StreamKey { get; private set; }

        /// <summary>
        /// 消息排序标识
        /// </summary>

        public long SequenceId { get; private set; }

        private Message() { }

        private Message(MessageCreateContext ctx, long sequenceId, MessageType messageType
            , MessageContent content
            )
        {
            ChatType = ctx.ChatType;
            SenderId = ctx.SenderId;
            ClientMsgId = ctx.ClientMsgId;
            TargetId = ctx.TargetId;
            SequenceId = sequenceId;
            MsgType = messageType;
            StreamKey = ChatType == ChatType.GROUP ? StreamKeyBuilder.Group(ctx.TargetId) : StreamKeyBuilder.Private(ctx.SenderId, ctx.TargetId);
            Content = content;
        }
        /// <summary>
        /// 文本消息
        /// </summary>
        /// <param name="ctx"></param>
        /// <param name="text">文本内容</param>
        /// <param name="sequenceId"></param>
        /// <returns></returns>
        public static Message BuildTxt(MessageCreateContext ctx, string text, long sequenceId)
        {
            var content = new MessageContent(text, new TextBody(text));
            return new Message(ctx, sequenceId, MessageType.Text, content);
        }
        /// <summary>
        /// 图片消息
        /// </summary>
        /// <param name="ctx"></param>
        /// <param name="url">相对路径</param>
        /// <param name="width">宽度</param>
        /// <param name="height">高度</param>
        /// <param name="thumb">预览图</param>
        /// <param name="sequenceId"></param>
        /// <returns></returns>
        public static Message BuildImg(MessageCreateContext ctx, string? url,
            int width, int height, string thumb, long sequenceId, Guid? fileId = null)
        {
            var content = new MessageContent("[图片]", new ImageBody(url, width, height, thumb, fileId));
            return new Message(ctx, sequenceId, MessageType.Image, content);
        }
        /// <summary>
        /// 视频消息
        /// </summary>
        /// <param name="ctx"></param>
        /// <param name="url"></param>
        /// <param name="width"></param>
        /// <param name="height"></param>
        /// <param name="thumb"></param>
        /// <param name="sequenceId"></param>
        /// <returns></returns>
        public static Message BuildVideo(MessageCreateContext ctx, string? url,
            int width, int height, string thumb, long sequenceId, Guid? fileId = null)
        {
            var content = new MessageContent("[视频]", new VideoBody(url, width, height, thumb, fileId));
            return new Message(ctx, sequenceId, MessageType.Video, content);
        }
        /// <summary>
        /// 语音消息
        /// </summary>
        /// <param name="ctx"></param>
        /// <param name="url"></param>
        /// <param name="duration">持续时间</param>
        /// <param name="sequenceId"></param>
        /// <returns></returns>
        public static Message BuildVoice(MessageCreateContext ctx, string? url,
            int duration, long sequenceId, Guid? fileId = null)
        {
            var content = new MessageContent("[音频]", new VoiceBody(url, duration, fileId));
            return new Message(ctx, sequenceId, MessageType.Voice, content);
        }
        /// <summary>
        /// 文件
        /// </summary>
        /// <param name="ctx"></param>
        /// <param name="url">相对路径</param>
        /// <param name="name">文件名</param>
        /// <param name="size">文件大小（KB）</param>
        /// <param name="format">文件格式</param>
        /// <param name="sequenceId"></param>
        /// <returns></returns>
        public static Message BuildFile(MessageCreateContext ctx, Guid fileId, string? url,
            string name, long size,
            string format, long sequenceId)
        {
            var content = new MessageContent("[文件]", new FileBody(fileId, url, name, size, format));
            return new Message(ctx, sequenceId, MessageType.File, content);
        }
        /// <summary>
        /// 添加扩展字段
        /// </summary>
        /// <param name="key">字段名</param>
        /// <param name="value">值</param>
        /// <returns></returns>
        public Message WithExt(string key, string value)
        {
            var dic = new Dictionary<string, string>();
            dic.Add(key, value);
            Content.RawExt = JsonSerializer.Serialize(dic);
            return this;
        }
        /// <summary>
        /// 添加消息引用
        /// </summary>
        /// <param name="quote"></param>
        /// <returns></returns>
        public Message WithQuote(QuoteInfo quote)
        {
            this.Content.Quote = quote;
            return this;
        }
        /// <summary>
        /// 完成消息
        /// </summary>
        public void Send()
        {
            AddDomainEvent(new MessageCreatedDomainEvent(this));
        }

        public void Withdraw()
        {
            if (State != MessageState.Sent)
            {
                throw new DomainException("消息不可撤回");
            }
            State = MessageState.Withdrwan;
            AddDomainEvent(new MessageWithdrawDomainEvent(this));
        }
        public MsgCreatedEvent ToIntegrationEvent()
        {
            return new MsgCreatedEvent
            {
                Id = this.Id,
                ClientId = this.ClientMsgId, // 假设你有存发送端的设备ID
                ChatType = this.ChatType.ToString(), // 比如 "private" 或 "group"
                MsgType = this.MsgType.ToString() ?? MessageType.Text.ToString(), // 动态获取类型名，或从 Content 里的定义拿
                SenderId = this.SenderId,
                TargetId = this.TargetId,
                State = State.ToString(),
                StreamKey = this.StreamKey,
                SequenceId = this.SequenceId,
                // 核心载荷：利用计算属性触发反序列化，打包成 DTO
                Content = new MsgContent(
                    this.Content.Fallback,
                    this.Content.Body, // 触发实体内部的反序列化逻辑
                    this.Content.Ext,
                    this.Content.Quote != null ? new QuoteInfoDto(
                        this.Content.Quote.MessageId,
                        this.Content.Quote.SenderId,
                        this.Content.Quote.SenderName,
                        this.Content.Quote.MessageType.ToString(),
                        this.Content.Quote.Preview
                    ) : null
                )
            };
        }

    }
}