public async Task <IReadOnlyCollection <ISocketMessage> > DownloadAsync(ulong?fromId, Direction dir, int limit)
{
//TODO: Test heavily, especially the ordering of messages
if (limit < 0)
{
throw new ArgumentOutOfRangeException(nameof(limit));
}
if (limit == 0)
{
return(ImmutableArray <ISocketMessage> .Empty);
}
var cachedMessages = GetMany(fromId, dir, limit);
if (cachedMessages.Count == limit)
{
return(cachedMessages);
}
else if (cachedMessages.Count > limit)
{
return(cachedMessages.Skip(cachedMessages.Count - limit).ToImmutableArray());
}
else
{
var args = new GetChannelMessagesParams
{
Limit = limit - cachedMessages.Count,
RelativeDirection = dir
};
if (cachedMessages.Count == 0)
{
if (fromId != null)
{
args.RelativeMessageId = fromId.Value;
}
}
else
{
args.RelativeMessageId = dir == Direction.Before ? cachedMessages[0].Id : cachedMessages[cachedMessages.Count - 1].Id;
}
var downloadedMessages = await _discord.ApiClient.GetChannelMessagesAsync(_channel.Id, args).ConfigureAwait(false);
var guild = (_channel as ISocketGuildChannel)?.Guild;
return(cachedMessages.Concat(downloadedMessages.Select(x =>
{
IUser user = _channel.GetUser(x.Author.Value.Id, true);
if (user == null)
{
var newUser = new User(x.Author.Value);
if (guild != null)
{
user = new GuildUser(guild, newUser);
}
else
{
user = newUser;
}
}
return Create(user, x);
})).ToImmutableArray());
}
}