/// <summary>
/// 标记消息为已读
/// </summary>
/// <param name="message">消息</param>
/// <returns>结果</returns>
public async Task <bool> NoteRead(ChatMessage message)
{
//判断消息是否位于消息列表中
if (!instance.MessageList.Contains(message))
{
//消息不存在返回假
return(false);
}
//调用消息控制器标记消息为已读
MessageController messageController = new MessageController(db.Messages);
messageController.SetMessage(message);
messageController.NoteRead();
//向服务器发送已读消息请求
client.NoteMessage(instance, message);
//更新话题时间戳
instance.Read = message.SeqId;
instance.LastUsed = ChatMessageBuilder.GetTimeStamp();
var dbContext = db.Topics.GetRepository();
await dbContext.UpsertTopic(instance);
//标记成功返回真
return(true);
}
/// <summary>
/// 新增消息
/// </summary>
/// <param name="message">消息</param>
/// <returns>结果</returns>
public async Task <bool> AddMessage(ChatMessage message)
{
//判断消息是否已存在
//if (instance.MessageList.Contains(message))
//{
//已存在则添加失败返回假
// return false;
//}
int newSeqId = message.SeqId;
int oldSeqId = instance.MessageList.Count == 0 ? instance.MinLocalSeqId : instance.MessageList[0].SeqId;
message.TopicName = instance.Name;
//判断是否为初次添加话题
if (oldSeqId == 0)
{
instance.MessageList.Add(message);
//更新本地消息序号
instance.MinLocalSeqId = newSeqId;
instance.MaxLocalSeqId = newSeqId;
//判断是否为历史消息
}
else if (oldSeqId >= newSeqId)
{
instance.MessageList.Insert(0, message);
instance.MinLocalSeqId = newSeqId;
}
else
{
instance.MessageList.Add(message);
instance.MaxLocalSeqId = newSeqId;
}
//调用消息控制器添加消息
MessageController messageController = new MessageController(db.Messages);
messageController.SetMessage(message);
messageController.UpsertMessage();
//话题更新时间戳
instance.Recieve = message.SeqId;
instance.LastUsed = ChatMessageBuilder.GetTimeStamp();
var dbContext = db.Topics.GetRepository();
await dbContext.UpsertTopic(instance);
//添加成功返回真
return(true);
}
/// <summary>
/// 设置话题对象
/// </summary>
/// <param name="topic">话题</param>
/// <returns></returns>
public async Task SetTopic(Topic topic)
{
instance = topic;
//初始化消息列表
MessageController messageController = new MessageController(db.Messages);
List <ChatMessage> messages = await messageController.GetMessages(instance, instance.Limit);
messages.ForEach(async m => await AddMessage(m));
//初始化话题订阅者列表
SubscriberController subscriberController = new SubscriberController(db.Subscribers);
instance.SubsriberList = await subscriberController.GetSubscribers(instance);
}
/// <summary>
/// 加载历史消息
/// </summary>
/// <returns></returns>
public async void LoadMessage()
{
//获得起始序号与截止序号
int before = instance.MessageList.Count == 0 ? instance.MinLocalSeqId : instance.MessageList[0].SeqId;
int since = (before - instance.Limit) > 0 ? before - instance.Limit : 0;
//判断范围
if (since >= instance.MinLocalSeqId)
{
//全部消息从数据库中加载
MessageController messageController = new MessageController(db.Messages);
List <ChatMessage> messages = await messageController.GetMessages(instance, since, before) as List <ChatMessage>;
messages.ForEach(async m => await AddMessage(m));
}
else if (before > instance.MinLocalSeqId)
{
//从数据加载部分消息
MessageController messageController = new MessageController(db.Messages);
List <ChatMessage> messages = await messageController.GetMessages(instance, since, before) as List <ChatMessage>;
messages.ForEach(async m => await AddMessage(m));
//更新截止序号
before = instance.MinLocalSeqId;
//剩余消息请求服务器
client.Load(instance, since, before);
}
else
{
//全部消息请求服务器
client.Load(instance, since, before);
}
//话题更新时间戳
instance.LastUsed = ChatMessageBuilder.GetTimeStamp();
var dbContext = db.Topics.GetRepository();
await dbContext.UpsertTopic(instance);
}
/// <summary>
/// 获取消息控制器
/// </summary>
/// <returns>消息控制器</returns>
public MessageController GetMessageController()
{
MessageController messageController = new MessageController(db.Messages);
return messageController;
}
/// <summary>
/// 删除消息
/// </summary>
/// <param name="message">消息</param>
/// <returns>结果</returns>
public async Task <bool> RemoveMessage(ChatMessage message)
{
//判断消息是否位于消息列表中
if (!instance.MessageList.Contains(message))
{
//消息不存在返回假
return(false);
}
//判断是否删除最新消息
if (message.SeqId == instance.MaxLocalSeqId)
{
int size = instance.MessageList.Count;
//判断是否删除完后消息列表为空
if (size <= 1)
{
//为空本地最大序号置为0
instance.MaxLocalSeqId = 0;
}
else
{
//不空更新本地最大序号
instance.MaxLocalSeqId = instance.MessageList[size - 2].SeqId;
}
}
//判断是否删除最先消息
if (message.SeqId == instance.MinLocalSeqId)
{
int size = instance.MessageList.Count;
//判断是否删除完后消息列表为空
if (size <= 1)
{
//为空本地最小序号置为0
instance.MinLocalSeqId = 0;
}
else
{
//不空更新本地最小序号
instance.MinLocalSeqId = instance.MessageList[1].SeqId;
}
}
//调用消息控制器删除消息
MessageController messageController = new MessageController(db.Messages);
messageController.SetMessage(message);
messageController.DeleteMessage();
//更新话题时间戳
instance.Clear = message.SeqId;
instance.MessageList.Remove(message);
instance.LastUsed = ChatMessageBuilder.GetTimeStamp();
var dbContext = db.Topics.GetRepository();
await dbContext.UpsertTopic(instance);
//向服务器发送删除消息请求
client.RemoveMessage(instance, message);
//删除成功返回真
return(true);
}