Move derivation of the synthesized view of channels (and messages) into `session`.

3 files changed, 52 insertions, 12 deletions

diff --git a/ui/lib/session.svelte.js b/ui/lib/session.svelte.js
index 21a391d..2dae3c4 100644
--- a/ui/lib/session.svelte.js
+++ b/ui/lib/session.svelte.js
@@ -6,16 +6,62 @@ import * as api from './apiServer.js';
 import * as r from './state/remote/state.svelte.js';
 import * as l from './state/local/channels.svelte.js';
 import { Watchdog } from './watchdog.js';
+import { DateTime } from 'luxon';
+import { render } from '$lib/markdown.js';
+
+class Channel {
+  static fromRemote({ at, id, name }, messages, meta) {
+    const sentAt = messages
+      .filter((message) => message.channel === id)
+      .map((message) => message.at);
+    const lastEventAt = Math.max(at, ...sentAt);
+    const lastReadAt = meta.get(id)?.lastReadAt;
+
+    const hasUnreads = lastReadAt === undefined || lastEventAt > lastReadAt;
+    return new Channel({ at, id, name, hasUnreads });
+  }
+
+  constructor({ at, id, name, hasUnreads }) {
+    this.at = at;
+    this.id = id;
+    this.name = name;
+    this.hasUnreads = hasUnreads;
+  }
+}
+
+class Message {
+  static fromRemote({ id, at, channel, sender, body, renderedBody }, users) {
+    return new Message({
+      id,
+      at,
+      channel,
+      sender: users.get(sender),
+      body,
+      renderedBody
+    });
+  }
+
+  constructor({ id, at, channel, sender, body, renderedBody }) {
+    this.id = id;
+    this.at = at;
+    this.channel = channel;
+    this.sender = sender;
+    this.body = body;
+    this.renderedBody = renderedBody;
+  }
+}
 
 class Session {
   remote = $state();
   local = $state();
   currentUser = $derived(this.remote.currentUser);
   users = $derived(this.remote.users.all);
-  channels = $derived(this.remote.channels.all);
   messages = $derived(
-    this.remote.messages.all.map((message) =>
-      message.resolve({ sender: (id) => this.users.get(id) })
+    this.remote.messages.all.map((message) => Message.fromRemote(message, this.users))
+  );
+  channels = $derived(
+    this.remote.channels.all.map((channel) =>
+      Channel.fromRemote(channel, this.messages, this.local.all)
     )
   );
 
diff --git a/ui/lib/state/remote/channels.svelte.js b/ui/lib/state/remote/channels.svelte.js
index b6da31b..8b190dd 100644
--- a/ui/lib/state/remote/channels.svelte.js
+++ b/ui/lib/state/remote/channels.svelte.js
@@ -1,5 +1,4 @@
 import { DateTime } from 'luxon';
-import { SvelteMap } from 'svelte/reactivity';
 
 class Channel {
   static boot({ at, id, name }) {
@@ -18,10 +17,10 @@ class Channel {
 }
 
 export class Channels {
-  all = $state();
+  all = $state([]);
 
   static boot(channels) {
-    const all = new SvelteMap(channels.map((channel) => [channel.id, Channel.boot(channel)]));
+    const all = channels.map((channel) => Channel.boot(channel));
     return new Channels({ all });
   }
 
diff --git a/ui/lib/state/remote/messages.svelte.js b/ui/lib/state/remote/messages.svelte.js
index c6d31f0..0a081bb 100644
--- a/ui/lib/state/remote/messages.svelte.js
+++ b/ui/lib/state/remote/messages.svelte.js
@@ -1,7 +1,7 @@
 import { DateTime } from 'luxon';
 import { render } from '$lib/markdown.js';
 
-export class Message {
+class Message {
   static boot({ id, at, channel, sender, body }) {
     return new Message({
       id,
@@ -21,11 +21,6 @@ export class Message {
     this.body = body;
     this.renderedBody = renderedBody;
   }
-
-  resolve(get) {
-    const { sender, ...rest } = this;
-    return new Message({ sender: get.sender(sender), ...rest });
-  }
 }
 
 export class Messages {