recap-relay/server/routes/analyze.js

// POST /relay/analyze — forwards an analysis prompt to the chosen
// backend and returns the standard envelope.
//
// Request body (application/json):
//   { prompt: string }
//
// Headers: same as /relay/transcribe (X-Recap-Install-Id required,
// X-Recap-Job-Id optional, Authorization optional Bearer license).
//
// Same charge-once-per-job semantics: a Recap summarize job pairs
// transcribe + analyze with the same X-Recap-Job-Id. The first call
// (whichever endpoint) charges 1 credit; the second is free.
//
// Every outcome (success / quota-refused / backend-error) writes one
// row to the audit log so the admin dashboard can compute cost,
// margin, and speed metrics.

import express from "express";
import { resolveLicense } from "../keysat-client.js";
import { getOrCreateRow, planBackend, commitCredit } from "../credits.js";
import { lookupJob, markJobCharged, refundJob } from "../job-credits.js";
import { getConfigSnapshot, getTierQuotas } from "../config.js";
import { createGeminiBackend } from "../backends/gemini.js";
import { createHardwareBackend } from "../backends/hardware.js";
import { envelope, errorEnvelope } from "./envelope.js";
import { recordCall } from "../audit-log.js";
import { calcGeminiCost } from "../pricing.js";

export function analyzeRouter() {
  const router = express.Router();

  router.post("/analyze", express.json({ limit: "10mb" }), async (req, res) => {
    const t0 = Date.now();
    const installId = req.header("X-Recap-Install-Id");
    const jobId = req.header("X-Recap-Job-Id") || null;
    const auth = req.header("Authorization");

    if (!installId) {
      const e = await errorEnvelope({
        error: "missing X-Recap-Install-Id header",
        statusHint: 400,
      });
      return res.status(400).json(e.body);
    }
    const prompt = req.body?.prompt;
    if (!prompt || typeof prompt !== "string") {
      const e = await errorEnvelope({
        error: "missing or non-string body.prompt",
        installId,
        statusHint: 400,
      });
      return res.status(400).json(e.body);
    }

    const license = await resolveLicense(auth);
    const tier = license.tier;

    const row = await getOrCreateRow(installId);
    row.tier_snapshot = tier;

    let reusedJob = false;
    let chosenBackend = null;
    const existingJob = lookupJob(installId, jobId);
    if (existingJob) {
      reusedJob = true;
      chosenBackend = existingJob.backend;
    } else {
      const cfg = await getConfigSnapshot();
      const hasHardware = !!cfg.relay_gemma_base_url;
      const quota = await getTierQuotas();
      const preference =
        cfg.relay_analyze_backend_preference || "gemini_first";
      const plan = planBackend(row, quota, { hasHardware, preference });
      if (!plan.allowed) {
        await recordCall({
          install_id: installId,
          tier,
          pipeline: "analyze",
          backend: null,
          model: null,
          status: "refused",
          credit_charged: 0,
          duration_ms: Date.now() - t0,
          cost_usd: 0,
          job_id: jobId,
          error: plan.reason,
        });
        const e = await errorEnvelope({
          error: plan.reason,
          installId,
          tier,
          statusHint: 402,
        });
        return res.status(402).json(e.body);
      }
      chosenBackend = plan.backend;
    }

    const cfg = await getConfigSnapshot();
    let result;
    try {
      if (chosenBackend === "gemini") {
        const backend = createGeminiBackend({
          apiKey: cfg.relay_gemini_api_key,
          transcriptionModel: cfg.relay_gemini_transcription_model,
          analysisModel: cfg.relay_gemini_analysis_model,
        });
        result = await backend.analyzeText({ prompt });
      } else {
        const backend = createHardwareBackend({
          parakeetBaseURL: cfg.relay_parakeet_base_url,
          gemmaBaseURL: cfg.relay_gemma_base_url,
          parakeetModel: cfg.relay_parakeet_model,
          gemmaModel: cfg.relay_gemma_model,
        });
        result = await backend.analyzeText({ prompt });
      }
    } catch (err) {
      if (reusedJob) refundJob(installId, jobId);
      console.error(`[relay/analyze] backend error: ${err?.message}`);
      await recordCall({
        install_id: installId,
        tier,
        pipeline: "analyze",
        backend: chosenBackend,
        model: chosenBackend === "gemini"
          ? cfg.relay_gemini_analysis_model
          : cfg.relay_gemma_model,
        status: "error",
        credit_charged: 0,
        duration_ms: Date.now() - t0,
        cost_usd: 0,
        job_id: jobId,
        error: (err?.message || String(err)).slice(0, 200),
      });
      const e = await errorEnvelope({
        error: err?.message || "backend_error",
        installId,
        tier,
        statusHint: err?.status || 502,
      });
      return res.status(e.statusHint).json(e.body);
    }

    let creditCharged = 0;
    if (!reusedJob) {
      await commitCredit(installId, { backend: chosenBackend, tier });
      markJobCharged(installId, jobId, { backend: chosenBackend, tier });
      creditCharged = 1;
    }

    const costDetails =
      chosenBackend === "gemini" && result.usage
        ? calcGeminiCost(result.model, result.usage)
        : {
            input_tokens: 0,
            output_tokens: 0,
            thinking_tokens: 0,
            cost_usd: 0,
          };
    await recordCall({
      install_id: installId,
      tier,
      pipeline: "analyze",
      backend: chosenBackend,
      model: result?.model || null,
      status: "success",
      credit_charged: creditCharged,
      duration_ms: Date.now() - t0,
      job_id: jobId,
      ...costDetails,
    });

    const body = await envelope({ result, installId, tier, creditCharged });
    res.json(body);
  });

  return router;
}