feat(web): add orchestrator command system in chat interface (#521)

Co-authored-by: Jason Woltje <jason@diversecanvas.com>
Co-committed-by: Jason Woltje <jason@diversecanvas.com>

apps/web/src/components/chat/ChatInput.tsx

@@ -2,6 +2,7 @@
 
 import type { KeyboardEvent, RefObject } from "react";
 import { useCallback, useState, useEffect, useRef } from "react";
+import { ORCHESTRATOR_COMMANDS } from "@/hooks/useOrchestratorCommands";
 
 export const AVAILABLE_MODELS = [
   { id: "llama3.2", label: "Llama 3.2" },
@@ -94,6 +95,11 @@ export function ChatInput({
   const [isModelDropdownOpen, setIsModelDropdownOpen] = useState(false);
   const [isParamsOpen, setIsParamsOpen] = useState(false);
 
+  // Command autocomplete state
+  const [commandSuggestions, setCommandSuggestions] = useState<typeof ORCHESTRATOR_COMMANDS>([]);
+  const [highlightedCommandIndex, setHighlightedCommandIndex] = useState(0);
+  const commandDropdownRef = useRef<HTMLDivElement>(null);
+
   const modelDropdownRef = useRef<HTMLDivElement>(null);
   const paramsDropdownRef = useRef<HTMLDivElement>(null);
 
@@ -147,6 +153,35 @@ export function ChatInput({
       });
   }, []);
 
+  // Update command autocomplete suggestions when message changes
+  useEffect(() => {
+    const trimmed = message.trimStart();
+    if (!trimmed.startsWith("/")) {
+      setCommandSuggestions([]);
+      setHighlightedCommandIndex(0);
+      return;
+    }
+
+    // If the input contains a space, a command has been completed — no suggestions
+    if (trimmed.includes(" ")) {
+      setCommandSuggestions([]);
+      setHighlightedCommandIndex(0);
+      return;
+    }
+
+    const typedCommand = trimmed.toLowerCase();
+
+    // Build flat list including aliases
+    const matches = ORCHESTRATOR_COMMANDS.filter((cmd) => {
+      if (cmd.name.startsWith(typedCommand)) return true;
+      if (cmd.aliases?.some((a) => a.startsWith(typedCommand))) return true;
+      return false;
+    });
+
+    setCommandSuggestions(matches);
+    setHighlightedCommandIndex(0);
+  }, [message]);
+
   // Close dropdowns on outside click
   useEffect(() => {
     const handleClickOutside = (e: MouseEvent): void => {
@@ -156,6 +191,9 @@ export function ChatInput({
       if (paramsDropdownRef.current && !paramsDropdownRef.current.contains(e.target as Node)) {
         setIsParamsOpen(false);
       }
+      if (commandDropdownRef.current && !commandDropdownRef.current.contains(e.target as Node)) {
+        setCommandSuggestions([]);
+      }
     };
     document.addEventListener("mousedown", handleClickOutside);
     return (): void => {
@@ -174,8 +212,48 @@ export function ChatInput({
     onStopStreaming?.();
   }, [onStopStreaming]);
 
+  const acceptCommand = useCallback((cmdName: string): void => {
+    setMessage(cmdName + " ");
+    setCommandSuggestions([]);
+    setHighlightedCommandIndex(0);
+  }, []);
+
   const handleKeyDown = useCallback(
     (e: KeyboardEvent<HTMLTextAreaElement>) => {
+      // Command autocomplete navigation
+      if (commandSuggestions.length > 0) {
+        if (e.key === "ArrowDown") {
+          e.preventDefault();
+          setHighlightedCommandIndex((prev) =>
+            prev < commandSuggestions.length - 1 ? prev + 1 : 0
+          );
+          return;
+        }
+        if (e.key === "ArrowUp") {
+          e.preventDefault();
+          setHighlightedCommandIndex((prev) =>
+            prev > 0 ? prev - 1 : commandSuggestions.length - 1
+          );
+          return;
+        }
+        if (
+          e.key === "Tab" ||
+          (e.key === "Enter" && !e.shiftKey && commandSuggestions.length > 0)
+        ) {
+          e.preventDefault();
+          const selected = commandSuggestions[highlightedCommandIndex];
+          if (selected) {
+            acceptCommand(selected.name);
+          }
+          return;
+        }
+        if (e.key === "Escape") {
+          e.preventDefault();
+          setCommandSuggestions([]);
+          return;
+        }
+      }
+
       if (e.key === "Enter" && !e.shiftKey) {
         e.preventDefault();
         handleSubmit();
@@ -185,7 +263,7 @@ export function ChatInput({
         handleSubmit();
       }
     },
-    [handleSubmit]
+    [handleSubmit, commandSuggestions, highlightedCommandIndex, acceptCommand]
   );
 
   const handleModelSelect = useCallback(
@@ -462,6 +540,55 @@ export function ChatInput({
         </div>
       </div>
 
+      {/* Command Autocomplete Dropdown */}
+      {commandSuggestions.length > 0 && (
+        <div
+          ref={commandDropdownRef}
+          className="rounded-lg border shadow-lg"
+          style={{
+            backgroundColor: "rgb(var(--surface-0))",
+            borderColor: "rgb(var(--border-default))",
+          }}
+          role="listbox"
+          aria-label="Command suggestions"
+          data-testid="command-autocomplete"
+        >
+          {commandSuggestions.map((cmd, idx) => (
+            <button
+              key={cmd.name}
+              role="option"
+              aria-selected={idx === highlightedCommandIndex}
+              onClick={() => {
+                acceptCommand(cmd.name);
+              }}
+              className="w-full flex items-center gap-3 px-3 py-2 text-left text-sm transition-colors first:rounded-t-lg last:rounded-b-lg"
+              style={{
+                backgroundColor:
+                  idx === highlightedCommandIndex
+                    ? "rgb(var(--accent-primary) / 0.1)"
+                    : "transparent",
+                color: "rgb(var(--text-primary))",
+              }}
+            >
+              <span
+                className="font-mono text-xs font-semibold"
+                style={{ color: "rgb(var(--accent-primary))" }}
+              >
+                {cmd.name}
+              </span>
+              {cmd.aliases && cmd.aliases.length > 0 && (
+                <span className="text-xs" style={{ color: "rgb(var(--text-muted))" }}>
+                  ({cmd.aliases.join(", ")})
+                </span>
+              )}
+              <span className="text-xs ml-auto" style={{ color: "rgb(var(--text-secondary))" }}>
+                {cmd.description}
+              </span>
+            </button>
+          ))}
+        </div>
+      )}
+
       {/* Input Container */}
       <div
         className="relative rounded-lg border transition-all duration-150"