Update API key usage and credit checking logic for comic generation

app/api/check-credits/route.ts

@@ -0,0 +1,71 @@
+import { type NextRequest, NextResponse } from "next/server";
+import { auth } from "@clerk/nextjs/server";
+import { freeTierRateLimit } from "@/lib/rate-limit";
+import { db } from "@/lib/db";
+import { stories } from "@/lib/schema";
+import { gte } from "drizzle-orm";
+
+export async function POST(request: NextRequest) {
+  try {
+    const { userId } = await auth();
+
+    if (!userId) {
+      return NextResponse.json(
+        { error: "Authentication required" },
+        { status: 401 }
+      );
+    }
+
+    const { hasApiKey } = await request.json();
+
+    // Check if user has API key (unlimited)
+    if (hasApiKey) {
+      return NextResponse.json({
+        hasApiKey: true,
+        creditsRemaining: "unlimited",
+        resetTime: null,
+      });
+    }
+
+    // For free tier, check rate limit status
+    try {
+      // Try to check remaining without consuming
+      const limitResult = await freeTierRateLimit.getRemaining(userId);
+
+      return NextResponse.json({
+        hasApiKey: false,
+        creditsRemaining: limitResult.remaining,
+        resetTime: limitResult.reset,
+      });
+    } catch (error) {
+      console.error("Rate limit check error:", error);
+      // Fallback to database check
+      const sevenDaysAgo = new Date();
+      sevenDaysAgo.setDate(sevenDaysAgo.getDate() - 7);
+
+      const recentStories = await db
+        .select()
+        .from(stories)
+        .where(gte(stories.createdAt, sevenDaysAgo))
+        .limit(1);
+
+      const hasUsedCredit = recentStories.length > 0;
+
+      return NextResponse.json({
+        hasApiKey: false,
+        creditsRemaining: hasUsedCredit ? 0 : 1,
+        resetTime: hasUsedCredit ? sevenDaysAgo.getTime() + 7 * 24 * 60 * 60 * 1000 : null,
+      });
+    }
+  } catch (error) {
+    console.error("Error in check-credits API:", error);
+    return NextResponse.json(
+      {
+        error: `Internal server error: ${
+          error instanceof Error ? error.message : "Unknown error"
+        }`,
+      },
+      { status: 500 }
+    );
+  }
+}