From b2c751caca5d5484ccf8d4e6e139b83d53d51a2e Mon Sep 17 00:00:00 2001
From: Jason Woltje <jason@diversecanvas.com>
Date: Sat, 7 Mar 2026 14:32:12 -0600
Subject: [PATCH] feat(web): MS23-P2-003 BargeInInput component

---
 .../mission-control/BargeInInput.tsx          | 147 ++++++++++++++++++
 .../mission-control/MissionControlLayout.tsx  |   2 +-
 .../mission-control/OrchestratorPanel.tsx     |  66 ++++----
 3 files changed, 184 insertions(+), 31 deletions(-)
 create mode 100644 apps/web/src/components/mission-control/BargeInInput.tsx

diff --git a/apps/web/src/components/mission-control/BargeInInput.tsx b/apps/web/src/components/mission-control/BargeInInput.tsx
new file mode 100644
index 0000000..d83c735
--- /dev/null
+++ b/apps/web/src/components/mission-control/BargeInInput.tsx
@@ -0,0 +1,147 @@
+"use client";
+
+import { useCallback, useState, type KeyboardEvent } from "react";
+import { Loader2 } from "lucide-react";
+import { useToast } from "@mosaic/ui";
+import { Button } from "@/components/ui/button";
+import { apiPost } from "@/lib/api/client";
+
+const MAX_ROWS = 4;
+const TEXTAREA_MAX_HEIGHT_REM = 6.5;
+
+interface BargeInMutationResponse {
+  message?: string;
+}
+
+export interface BargeInInputProps {
+  sessionId: string;
+  onSent?: () => void;
+}
+
+function getErrorMessage(error: unknown): string {
+  if (error instanceof Error && error.message.trim().length > 0) {
+    return error.message;
+  }
+  return "Failed to send message to the session.";
+}
+
+export function BargeInInput({ sessionId, onSent }: BargeInInputProps): React.JSX.Element {
+  const { showToast } = useToast();
+  const [content, setContent] = useState("");
+  const [pauseBeforeSend, setPauseBeforeSend] = useState(false);
+  const [isSending, setIsSending] = useState(false);
+  const [errorMessage, setErrorMessage] = useState<string | null>(null);
+
+  const handleSend = useCallback(async (): Promise<void> => {
+    const trimmedContent = content.trim();
+    if (!trimmedContent || isSending) {
+      return;
+    }
+
+    const encodedSessionId = encodeURIComponent(sessionId);
+    const baseEndpoint = `/api/mission-control/sessions/${encodedSessionId}`;
+    let didPause = false;
+    let didInject = false;
+
+    setIsSending(true);
+    setErrorMessage(null);
+
+    try {
+      if (pauseBeforeSend) {
+        await apiPost<BargeInMutationResponse>(`${baseEndpoint}/pause`);
+        didPause = true;
+      }
+
+      await apiPost<BargeInMutationResponse>(`${baseEndpoint}/inject`, { content: trimmedContent });
+      didInject = true;
+      setContent("");
+      onSent?.();
+    } catch (error) {
+      const message = getErrorMessage(error);
+      setErrorMessage(message);
+      showToast(message, "error");
+    } finally {
+      if (didPause) {
+        try {
+          await apiPost<BargeInMutationResponse>(`${baseEndpoint}/resume`);
+        } catch (resumeError) {
+          const resumeMessage = getErrorMessage(resumeError);
+          const message = didInject
+            ? `Message sent, but failed to resume session: ${resumeMessage}`
+            : `Failed to resume session: ${resumeMessage}`;
+          setErrorMessage(message);
+          showToast(message, "error");
+        }
+      }
+
+      setIsSending(false);
+    }
+  }, [content, isSending, onSent, pauseBeforeSend, sessionId, showToast]);
+
+  const handleKeyDown = useCallback(
+    (event: KeyboardEvent<HTMLTextAreaElement>): void => {
+      if (event.key === "Enter" && !event.shiftKey) {
+        event.preventDefault();
+        void handleSend();
+      }
+    },
+    [handleSend]
+  );
+
+  const isSendDisabled = isSending || content.trim().length === 0;
+
+  return (
+    <div className="space-y-2">
+      <textarea
+        value={content}
+        onChange={(event) => {
+          setContent(event.target.value);
+        }}
+        onKeyDown={handleKeyDown}
+        disabled={isSending}
+        rows={MAX_ROWS}
+        placeholder="Inject a message into this session..."
+        className="block w-full resize-y rounded-md border border-border bg-background px-3 py-2 text-sm leading-5 text-foreground outline-none placeholder:text-muted-foreground disabled:cursor-not-allowed disabled:opacity-60"
+        style={{ maxHeight: `${String(TEXTAREA_MAX_HEIGHT_REM)}rem` }}
+        aria-label="Inject message"
+      />
+      <div className="flex items-center justify-between gap-3">
+        <label className="flex items-center gap-2 text-sm text-muted-foreground">
+          <input
+            type="checkbox"
+            checked={pauseBeforeSend}
+            onChange={(event) => {
+              setPauseBeforeSend(event.target.checked);
+            }}
+            disabled={isSending}
+            className="h-4 w-4 rounded border-border"
+          />
+          <span>Pause before send</span>
+        </label>
+        <Button
+          type="button"
+          variant="primary"
+          size="sm"
+          disabled={isSendDisabled}
+          onClick={() => {
+            void handleSend();
+          }}
+        >
+          {isSending ? (
+            <span className="flex items-center gap-2">
+              <Loader2 className="h-4 w-4 animate-spin" aria-hidden="true" />
+              Sending...
+            </span>
+          ) : (
+            "Send"
+          )}
+        </Button>
+      </div>
+      {errorMessage ? (
+        <p role="alert" className="text-sm text-red-500">
+          {errorMessage}
+        </p>
+      ) : null}
+    </div>
+  );
+}
diff --git a/apps/web/src/components/mission-control/MissionControlLayout.tsx b/apps/web/src/components/mission-control/MissionControlLayout.tsx
index c779899..8e93150 100644
--- a/apps/web/src/components/mission-control/MissionControlLayout.tsx
+++ b/apps/web/src/components/mission-control/MissionControlLayout.tsx
@@ -21,7 +21,7 @@ export function MissionControlLayout(): React.JSX.Element {
         <aside className="h-full min-h-0">
           <GlobalAgentRoster
             onSelectSession={setSelectedSessionId}
-            selectedSessionId={selectedSessionId}
+            {...(selectedSessionId ? { selectedSessionId } : {})}
           />
         </aside>
         <main className="h-full min-h-0 overflow-hidden">
diff --git a/apps/web/src/components/mission-control/OrchestratorPanel.tsx b/apps/web/src/components/mission-control/OrchestratorPanel.tsx
index f703e75..81f78d0 100644
--- a/apps/web/src/components/mission-control/OrchestratorPanel.tsx
+++ b/apps/web/src/components/mission-control/OrchestratorPanel.tsx
@@ -2,6 +2,7 @@
 
 import { useEffect, useRef } from "react";
 import { formatDistanceToNow } from "date-fns";
+import { BargeInInput } from "@/components/mission-control/BargeInInput";
 import { Badge } from "@/components/ui/badge";
 import type { BadgeVariant } from "@/components/ui/badge";
 import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
@@ -82,36 +83,41 @@ export function OrchestratorPanel({ sessionId }: OrchestratorPanelProps): React.
         </div>
         <p className="truncate text-xs text-muted-foreground">Session: {sessionId}</p>
       </CardHeader>
-      <CardContent className="flex min-h-0 flex-1 p-0">
-        <ScrollArea className="h-full w-full">
-          <div className="flex min-h-full flex-col gap-3 p-4">
-            {messages.length === 0 ? (
-              <p className="mt-6 text-center text-sm text-muted-foreground">
-                {error ?? "Waiting for messages..."}
-              </p>
-            ) : (
-              messages.map((message) => (
-                <article
-                  key={message.id}
-                  className="rounded-lg border border-border/70 bg-card px-3 py-2"
-                >
-                  <div className="mb-2 flex items-center justify-between gap-2">
-                    <Badge variant={ROLE_BADGE_VARIANT[message.role]} className="uppercase">
-                      {message.role}
-                    </Badge>
-                    <time className="text-xs text-muted-foreground">
-                      {formatRelativeTimestamp(message.timestamp)}
-                    </time>
-                  </div>
-                  <p className="whitespace-pre-wrap break-words text-sm text-foreground">
-                    {message.content}
-                  </p>
-                </article>
-              ))
-            )}
-            <div ref={bottomAnchorRef} />
-          </div>
-        </ScrollArea>
+      <CardContent className="flex min-h-0 flex-1 flex-col p-0">
+        <div className="min-h-0 flex-1">
+          <ScrollArea className="h-full w-full">
+            <div className="flex min-h-full flex-col gap-3 p-4">
+              {messages.length === 0 ? (
+                <p className="mt-6 text-center text-sm text-muted-foreground">
+                  {error ?? "Waiting for messages..."}
+                </p>
+              ) : (
+                messages.map((message) => (
+                  <article
+                    key={message.id}
+                    className="rounded-lg border border-border/70 bg-card px-3 py-2"
+                  >
+                    <div className="mb-2 flex items-center justify-between gap-2">
+                      <Badge variant={ROLE_BADGE_VARIANT[message.role]} className="uppercase">
+                        {message.role}
+                      </Badge>
+                      <time className="text-xs text-muted-foreground">
+                        {formatRelativeTimestamp(message.timestamp)}
+                      </time>
+                    </div>
+                    <p className="whitespace-pre-wrap break-words text-sm text-foreground">
+                      {message.content}
+                    </p>
+                  </article>
+                ))
+              )}
+              <div ref={bottomAnchorRef} />
+            </div>
+          </ScrollArea>
+        </div>
+        <div className="border-t border-border/70 p-3">
+          <BargeInInput sessionId={sessionId} />
+        </div>
       </CardContent>
     </Card>
   );