feat(differentials): polish search results UX and mobile compare bar

src/app/differentials/presentations/[slug]/page.tsx

@@ -6,7 +6,7 @@ import { getPresentationWorkflow, presentationStaticParams } from "@/lib/differe
 
 type DifferentialPresentationRouteProps = {
   params: Promise<{ slug: string }>;
-  searchParams?: Promise<{ query?: string | string[]; q?: string | string[] }>;
+  searchParams?: Promise<{ query?: string | string[]; q?: string | string[]; ids?: string | string[] }>;
 };
 
 function firstSearchParam(value?: string | string[]) {
@@ -36,6 +36,10 @@ export default async function DifferentialPresentationRoute({
 
   const resolvedSearchParams = searchParams ? await searchParams : {};
   const query = firstSearchParam(resolvedSearchParams.query ?? resolvedSearchParams.q)?.trim() ?? "";
+  const selectedIds = (firstSearchParam(resolvedSearchParams.ids) ?? "")
+    .split(",")
+    .map((value) => value.trim())
+    .filter(Boolean);
 
-  return <DifferentialPresentationWorkflowPage query={query} presentationSlug={slug} />;
+  return <DifferentialPresentationWorkflowPage query={query} presentationSlug={slug} selectedIds={selectedIds} />;
 }

src/app/differentials/presentations/page.tsx

@@ -1,7 +1,9 @@
 import { redirect } from "next/navigation";
 
+import { getPresentationWorkflowSelectionForDiagnosisIds } from "@/lib/differentials";
+
 type DifferentialPresentationsRouteProps = {
-  searchParams?: Promise<{ query?: string | string[]; q?: string | string[] }>;
+  searchParams?: Promise<{ query?: string | string[]; q?: string | string[]; ids?: string | string[] }>;
 };
 
 function firstSearchParam(value?: string | string[]) {
@@ -11,6 +13,15 @@ function firstSearchParam(value?: string | string[]) {
 export default async function DifferentialPresentationsRoute({ searchParams }: DifferentialPresentationsRouteProps) {
   const params = searchParams ? await searchParams : {};
   const query = firstSearchParam(params.query ?? params.q)?.trim();
-  const suffix = query ? `?q=${encodeURIComponent(query)}` : "";
-  redirect(`/differentials/presentations/acute-confusion-encephalopathy${suffix}`);
+  const ids = firstSearchParam(params.ids)?.trim();
+  const selectedIds = (ids ?? "")
+    .split(",")
+    .map((id) => id.trim())
+    .filter(Boolean);
+  const selection = getPresentationWorkflowSelectionForDiagnosisIds(selectedIds);
+  const destinationParams = new URLSearchParams();
+  if (query) destinationParams.set("q", query);
+  if (selection?.diagnosisIds.length) destinationParams.set("ids", selection.diagnosisIds.join(","));
+  const suffix = destinationParams.size ? `?${destinationParams.toString()}` : "";
+  redirect(`/differentials/presentations/${selection?.workflow.id ?? "acute-confusion-encephalopathy"}${suffix}`);
 }