feat: add 'Generate architecture' CTA banner on PRD page when arch not yet generated

Made-with: Cursor

app/[workspace]/project/[projectId]/prd/page.tsx

@@ -1,7 +1,7 @@
 "use client";
 
 import { useEffect, useState } from "react";
-import { useParams } from "next/navigation";
+import { useParams, useRouter } from "next/navigation";
 
 // Maps each PRD section to the discovery phase that populates it
 const PRD_SECTIONS = [
@@ -184,11 +184,14 @@ function ArchitectureView({ arch }: { arch: Architecture }) {
 export default function PRDPage() {
   const params = useParams();
   const projectId = params.projectId as string;
+  const workspace = params.workspace as string;
   const [prd, setPrd] = useState<string | null>(null);
   const [architecture, setArchitecture] = useState<Architecture | null>(null);
   const [savedPhases, setSavedPhases] = useState<SavedPhase[]>([]);
   const [loading, setLoading] = useState(true);
   const [activeTab, setActiveTab] = useState<"prd" | "architecture">("prd");
+  const [archGenerating, setArchGenerating] = useState(false);
+  const [archError, setArchError] = useState<string | null>(null);
 
   useEffect(() => {
     Promise.all([
@@ -202,6 +205,24 @@ export default function PRDPage() {
     });
   }, [projectId]);
 
+  const router = useRouter();
+
+  const handleGenerateArchitecture = async () => {
+    setArchGenerating(true);
+    setArchError(null);
+    try {
+      const res = await fetch(`/api/projects/${projectId}/architecture`, { method: "POST" });
+      const data = await res.json();
+      if (!res.ok) throw new Error(data.error ?? "Generation failed");
+      setArchitecture(data.architecture);
+      setActiveTab("architecture");
+    } catch (e) {
+      setArchError(e instanceof Error ? e.message : "Something went wrong");
+    } finally {
+      setArchGenerating(false);
+    }
+  };
+
   const phaseMap = new Map(savedPhases.map(p => [p.phase, p]));
   const savedPhaseIds = new Set(savedPhases.map(p => p.phase));
 
@@ -257,6 +278,51 @@ export default function PRDPage() {
         </div>
       )}
 
+      {/* Next step banner — PRD done but no architecture yet */}
+      {prd && !architecture && activeTab === "prd" && (
+        <div style={{
+          marginBottom: 24, padding: "18px 22px",
+          background: "#1a1a1a", borderRadius: 10,
+          display: "flex", alignItems: "center", justifyContent: "space-between",
+          gap: 16, flexWrap: "wrap",
+        }}>
+          <div>
+            <div style={{ fontSize: "0.88rem", fontWeight: 700, color: "#fff", marginBottom: 4 }}>
+              Next: Generate technical architecture
+            </div>
+            <div style={{ fontSize: "0.76rem", color: "#a09a90", lineHeight: 1.5 }}>
+              The AI will read your PRD and recommend the apps, services, and infrastructure your product needs. Takes ~30 seconds.
+            </div>
+            {archError && (
+              <div style={{ fontSize: "0.74rem", color: "#f87171", marginTop: 6 }}>⚠ {archError}</div>
+            )}
+          </div>
+          <button
+            onClick={handleGenerateArchitecture}
+            disabled={archGenerating}
+            style={{
+              padding: "10px 20px", borderRadius: 8, border: "none",
+              background: archGenerating ? "#4a4640" : "#fff",
+              color: archGenerating ? "#a09a90" : "#1a1a1a",
+              fontSize: "0.82rem", fontWeight: 700,
+              fontFamily: "Outfit, sans-serif",
+              cursor: archGenerating ? "default" : "pointer",
+              flexShrink: 0, display: "flex", alignItems: "center", gap: 8,
+              transition: "opacity 0.15s",
+            }}
+          >
+            {archGenerating && (
+              <span style={{
+                width: 12, height: 12, borderRadius: "50%",
+                border: "2px solid #60606040", borderTopColor: "#a09a90",
+                animation: "spin 0.7s linear infinite", display: "inline-block",
+              }} />
+            )}
+            {archGenerating ? "Analysing PRD…" : "Generate architecture →"}
+          </button>
+        </div>
+      )}
+
       {/* Architecture tab */}
       {activeTab === "architecture" && architecture && (
         <ArchitectureView arch={architecture} />