Initial commit: PodcastYes — AI podcast platform

lib/ai/cost.ts

@@ -0,0 +1,52 @@
+import { prisma } from "@/lib/db";
+import type { TokenUsage } from "./types";
+
+// Rough 2026 unit prices (USD). Tune in one place; admin cost dashboards read AiCostLog.
+const PRICE = {
+  gptInputPer1k: 0.0025,
+  gptOutputPer1k: 0.01,
+  elevenPer1kChars: 0.3,
+  dallePerImage: 0.04,
+};
+
+export function scriptCostUsd(usage: TokenUsage): number {
+  return round4(
+    (usage.inputTokens / 1000) * PRICE.gptInputPer1k +
+      (usage.outputTokens / 1000) * PRICE.gptOutputPer1k
+  );
+}
+
+export function audioCostUsd(characters: number): number {
+  return round4((characters / 1000) * PRICE.elevenPer1kChars);
+}
+
+export function artCostUsd(images: number): number {
+  return round4(images * PRICE.dallePerImage);
+}
+
+export interface CostEntry {
+  provider: "openai" | "elevenlabs";
+  operation: "script" | "audio" | "art" | "repurpose";
+  units: number;
+  costUsd: number;
+  episodeId?: string;
+  userId?: string;
+}
+
+/** Record an AI usage/cost line for the admin monitoring dashboard. */
+export async function recordCost(entry: CostEntry): Promise<void> {
+  await prisma.aiCostLog.create({
+    data: {
+      provider: entry.provider,
+      operation: entry.operation,
+      units: entry.units,
+      costUsd: entry.costUsd.toFixed(4),
+      episodeId: entry.episodeId,
+      userId: entry.userId,
+    },
+  });
+}
+
+function round4(n: number): number {
+  return Math.round(n * 10000) / 10000;
+}