feat: add Mattermost channel support

Add Mattermost as a supported messaging channel with bot API and WebSocket integration. Includes channel state tracking (tint, summary, details), multi-account support, and delivery target routing. Update documentation and tests to include Mattermost alongside existing channels.

ui/src/ui/types.ts

@@ -164,6 +164,39 @@ export type SlackStatus = {
   lastProbeAt?: number | null;
 };
 
+export type MattermostBot = {
+  id?: string | null;
+  username?: string | null;
+};
+
+export type MattermostProbe = {
+  ok: boolean;
+  status?: number | null;
+  error?: string | null;
+  elapsedMs?: number | null;
+  bot?: MattermostBot | null;
+};
+
+export type MattermostStatus = {
+  configured: boolean;
+  botTokenSource?: string | null;
+  running: boolean;
+  connected?: boolean | null;
+  lastConnectedAt?: number | null;
+  lastDisconnect?: {
+    at: number;
+    status?: number | null;
+    error?: string | null;
+    loggedOut?: boolean | null;
+  } | null;
+  lastStartAt?: number | null;
+  lastStopAt?: number | null;
+  lastError?: string | null;
+  baseUrl?: string | null;
+  probe?: MattermostProbe | null;
+  lastProbeAt?: number | null;
+};
+
 export type SignalProbe = {
   ok: boolean;
   status?: number | null;
@@ -363,6 +396,7 @@ export type CronPayload =
         | "telegram"
         | "discord"
         | "slack"
+        | "mattermost"
         | "signal"
         | "imessage"
         | "msteams";

ui/src/ui/views/channels.mattermost.ts

@@ -0,0 +1,70 @@
+import { html, nothing } from "lit";
+
+import { formatAgo } from "../format";
+import type { MattermostStatus } from "../types";
+import type { ChannelsProps } from "./channels.types";
+import { renderChannelConfigSection } from "./channels.config";
+
+export function renderMattermostCard(params: {
+  props: ChannelsProps;
+  mattermost?: MattermostStatus | null;
+  accountCountLabel: unknown;
+}) {
+  const { props, mattermost, accountCountLabel } = params;
+
+  return html`
+    <div class="card">
+      <div class="card-title">Mattermost</div>
+      <div class="card-sub">Bot token + WebSocket status and configuration.</div>
+      ${accountCountLabel}
+
+      <div class="status-list" style="margin-top: 16px;">
+        <div>
+          <span class="label">Configured</span>
+          <span>${mattermost?.configured ? "Yes" : "No"}</span>
+        </div>
+        <div>
+          <span class="label">Running</span>
+          <span>${mattermost?.running ? "Yes" : "No"}</span>
+        </div>
+        <div>
+          <span class="label">Connected</span>
+          <span>${mattermost?.connected ? "Yes" : "No"}</span>
+        </div>
+        <div>
+          <span class="label">Base URL</span>
+          <span>${mattermost?.baseUrl || "n/a"}</span>
+        </div>
+        <div>
+          <span class="label">Last start</span>
+          <span>${mattermost?.lastStartAt ? formatAgo(mattermost.lastStartAt) : "n/a"}</span>
+        </div>
+        <div>
+          <span class="label">Last probe</span>
+          <span>${mattermost?.lastProbeAt ? formatAgo(mattermost.lastProbeAt) : "n/a"}</span>
+        </div>
+      </div>
+
+      ${mattermost?.lastError
+        ? html`<div class="callout danger" style="margin-top: 12px;">
+            ${mattermost.lastError}
+          </div>`
+        : nothing}
+
+      ${mattermost?.probe
+        ? html`<div class="callout" style="margin-top: 12px;">
+            Probe ${mattermost.probe.ok ? "ok" : "failed"} -
+            ${mattermost.probe.status ?? ""} ${mattermost.probe.error ?? ""}
+          </div>`
+        : nothing}
+
+      ${renderChannelConfigSection({ channelId: "mattermost", props })}
+
+      <div class="row" style="margin-top: 12px;">
+        <button class="btn" @click=${() => props.onRefresh(true)}>
+          Probe
+        </button>
+      </div>
+    </div>
+  `;
+}

ui/src/ui/views/channels.ts

@@ -7,6 +7,7 @@ import type {
   ChannelsStatusSnapshot,
   DiscordStatus,
   IMessageStatus,
+  MattermostStatus,
   NostrProfile,
   NostrStatus,
   SignalStatus,
@@ -23,6 +24,7 @@ import { channelEnabled, renderChannelAccountCount } from "./channels.shared";
 import { renderChannelConfigSection } from "./channels.config";
 import { renderDiscordCard } from "./channels.discord";
 import { renderIMessageCard } from "./channels.imessage";
+import { renderMattermostCard } from "./channels.mattermost";
 import { renderNostrCard } from "./channels.nostr";
 import { renderSignalCard } from "./channels.signal";
 import { renderSlackCard } from "./channels.slack";
@@ -39,6 +41,7 @@ export function renderChannels(props: ChannelsProps) {
     | undefined;
   const discord = (channels?.discord ?? null) as DiscordStatus | null;
   const slack = (channels?.slack ?? null) as SlackStatus | null;
+  const mattermost = (channels?.mattermost ?? null) as MattermostStatus | null;
   const signal = (channels?.signal ?? null) as SignalStatus | null;
   const imessage = (channels?.imessage ?? null) as IMessageStatus | null;
   const nostr = (channels?.nostr ?? null) as NostrStatus | null;
@@ -62,6 +65,7 @@ export function renderChannels(props: ChannelsProps) {
           telegram,
           discord,
           slack,
+          mattermost,
           signal,
           imessage,
           nostr,
@@ -97,7 +101,7 @@ function resolveChannelOrder(snapshot: ChannelsStatusSnapshot | null): ChannelKe
   if (snapshot?.channelOrder?.length) {
     return snapshot.channelOrder;
   }
-  return ["whatsapp", "telegram", "discord", "slack", "signal", "imessage", "nostr"];
+  return ["whatsapp", "telegram", "discord", "slack", "mattermost", "signal", "imessage", "nostr"];
 }
 
 function renderChannel(
@@ -135,6 +139,12 @@ function renderChannel(
         slack: data.slack,
         accountCountLabel,
       });
+    case "mattermost":
+      return renderMattermostCard({
+        props,
+        mattermost: data.mattermost,
+        accountCountLabel,
+      });
     case "signal":
       return renderSignalCard({
         props,

ui/src/ui/views/channels.types.ts

@@ -4,6 +4,7 @@ import type {
   ConfigUiHints,
   DiscordStatus,
   IMessageStatus,
+  MattermostStatus,
   NostrProfile,
   NostrStatus,
   SignalStatus,
@@ -53,6 +54,7 @@ export type ChannelsChannelData = {
   telegram?: TelegramStatus;
   discord?: DiscordStatus | null;
   slack?: SlackStatus | null;
+  mattermost?: MattermostStatus | null;
   signal?: SignalStatus | null;
   imessage?: IMessageStatus | null;
   nostr?: NostrStatus | null;