Gateway Architecture

import { createOpenAI } from '@ai-sdk/openai';

// Layers provider instance
const layers = createOpenAI({
  baseURL: 'https://layers.hustletogether.com/api/v1',
  apiKey: process.env.LAYERS_API_KEY,
});

export function getProvider(modelId: string, useLayers: boolean) {
  if (useLayers) {
    return layers.chat(modelId);  // → layers.hustletogether.com
  }
  return modelId;  // → Direct AI Gateway
}

import { generateText } from 'ai';
import { getProvider } from '@/lib/models/get-provider';

export async function POST(req: Request) {
  const { model, prompt, useLayers } = await req.json();

  const result = await generateText({
    model: getProvider(model, useLayers),
    prompt,
  });

  return Response.json({ text: result.text });
}

export async function POST(req: Request) {
  const body = await req.json();
  const apiKey = req.headers.get('Authorization');

  // 1. Authenticate
  const user = await validateApiKey(apiKey);

  // 2. Check rate limits
  const rateLimit = checkRateLimit(user.id, user.tier);
  if (!rateLimit.allowed) return rateLimit.response;

  // 3. Pre-check credits
  const estimated = estimateCredits(body.model, body.max_tokens);
  if (user.balance < estimated) return insufficientCredits();

  // 4. Call AI provider via SDK
  const result = await generateText({
    model: gateway(body.model),  // Routes based on prefix
    ...body
  });

  // 5. Calculate actual credits and deduct
  const { credits, breakdown } = calculateCreditsWithBreakdown(
    body.model,
    result.usage.promptTokens,
    result.usage.completionTokens
  );
  await deductCredits(user.id, credits);
  await logUsage({ user, model: body.model, credits, breakdown });

  // 6. Return response with Layers metadata
  return Response.json({
    ...result,
    layers: { credits_used: credits, cost_breakdown: breakdown }
  });
}

// Pricing is synced from Hustle Together AI
// Source: https://ai.hustletogether.com/api/pricing
// Frequency: Every 24 hours (cached)

// When calculating credits:
const syncedPricing = getSyncedModelPricing(model);
const baseCost = (inputTokens / 1000) * syncedPricing.input
               + (outputTokens / 1000) * syncedPricing.output;
const credits = (baseCost / 0.01) * (1 + marginPercent / 100);