scaffold: Next.js 15 + Drizzle + Better Auth + OpenAI + Recharts base

src/lib/llm/index.ts

@@ -0,0 +1,65 @@
+import type {
+  ComparisonRequest,
+  ComparisonResult,
+  ResearchProgress,
+} from "./types";
+import { generateComparison } from "./providers/openai";
+
+export type {
+  ComparisonRequest,
+  ComparisonResult,
+  ResearchProgress,
+} from "./types";
+
+export async function* runResearch(
+  request: ComparisonRequest
+): AsyncGenerator<ResearchProgress> {
+  yield { stage: "parsing", message: "Analyzing comparison request..." };
+
+  if (!request.items || request.items.length < 2) {
+    yield {
+      stage: "error",
+      error: "At least 2 items are required for comparison",
+    };
+    return;
+  }
+
+  for (let i = 0; i < request.items.length; i++) {
+    yield {
+      stage: "researching",
+      item: request.items[i],
+      progress: Math.round(((i + 0.5) / request.items.length) * 80),
+    };
+  }
+
+  yield {
+    stage: "synthesizing",
+    message: "Synthesizing research into structured comparison...",
+  };
+
+  try {
+    const result = await generateComparison(request);
+    yield { stage: "complete", result };
+  } catch (error) {
+    yield {
+      stage: "error",
+      error:
+        error instanceof Error ? error.message : "Research failed unexpectedly",
+    };
+  }
+}
+
+export async function executeResearch(
+  request: ComparisonRequest
+): Promise<ComparisonResult> {
+  for await (const progress of runResearch(request)) {
+    if (progress.stage === "complete") {
+      return progress.result;
+    }
+    if (progress.stage === "error") {
+      throw new Error(progress.error);
+    }
+  }
+
+  throw new Error("Research completed without producing a result");
+}