Restructuring read_marker to be a field of a Metadata struct.

Disallow calling `send_markread` with a value-less `read_marker`.

data/src/client.rs

@@ -6,7 +6,7 @@ use std::collections::{BTreeMap, HashMap, HashSet};
 use std::fmt;
 use std::time::{Duration, Instant};
 
-use crate::history::read_marker_to_string;
+use crate::history::metadata::read_marker_to_string;
 use crate::message::server_time;
 use crate::time::Posix;
 use crate::user::{Nick, NickRef};
@@ -80,7 +80,7 @@ pub enum Event {
  Broadcast(Broadcast),
  Notification(message::Encoded, Nick, Notification),
  FileTransferRequest(file_transfer::ReceiveRequest),
- LoadReadMarker(String),
+ LoadHistoryMetadata(String),
  UpdateReadMarker(String, Option<DateTime<Utc>>),
 }
 
@@ -1256,15 +1256,13 @@ impl Client {
  Some(vec![Event::Single(message, self.nickname().to_owned())])
  }
 
- pub fn send_markread(&mut self, target: &str, read_marker: Option<DateTime<Utc>>) {
+ pub fn send_markread(&mut self, target: &str, read_marker: DateTime<Utc>) {
  if self.supports_read_marker {
- if let Some(read_marker) = read_marker {
- let _ = self.handle.try_send(command!(
- "MARKREAD",
- target.to_string(),
- format!("timestamp={}", read_marker_to_string(&Some(read_marker))),
- ));
- }
+ let _ = self.handle.try_send(command!(
+ "MARKREAD",
+ target.to_string(),
+ format!("timestamp={}", read_marker_to_string(&Some(read_marker))),
+ ));
  }
  }
 
@@ -1467,12 +1465,7 @@ impl Map {
  }
  }
 
- pub fn send_markread(
- &mut self,
- server: &Server,
- target: &str,
- read_marker: Option<DateTime<Utc>>,
- ) {
+ pub fn send_markread(&mut self, server: &Server, target: &str, read_marker: DateTime<Utc>) {
  if let Some(client) = self.client_mut(server) {
  client.send_markread(target, read_marker);
  }