import { readFile, writeFile } from "node:fs/promises";

import { evaluateBundleBudget } from "../src/application/policies/performance-budgets.js";
import { classifyViteJavascript } from "./lib/classify-vite-bundle.mjs";

const report =
  /** @type {{
   *   outputs: Array<{ path: string, gzipBytes: number }>,
   *   [key: string]: unknown
   * }} */ (
    JSON.parse(await readFile("artifacts/performance/bundle.json", "utf8"))
  );
const viteManifest =
  /** @type {Record<string, { file: string, isEntry?: boolean, imports?: string[] }>} */ (
    JSON.parse(await readFile("dist/.vite/manifest.json", "utf8"))
  );
const budgets =
  /** @type {{ initialJsGzipBytes: number, lazyChunkGzipBytes: number }} */ (
    JSON.parse(await readFile("config/performance/budgets.json", "utf8")).bundle
  );

const outputByPath = new Map(
  report.outputs.map((output) => [output.path.replace(/^dist\//, ""), output]),
);
const classification = classifyViteJavascript(viteManifest);
const initialJsGzipBytes = classification.initialFiles.reduce(
  (total, file) => total + (outputByPath.get(file)?.gzipBytes ?? 0),
  0,
);
const lazyChunks = classification.lazyFiles.map((file) => ({
  path: file,
  gzipBytes: outputByPath.get(file)?.gzipBytes ?? 0,
}));
const missingOutputs = [
  ...classification.initialFiles,
  ...classification.lazyFiles,
].filter((file) => !outputByPath.has(file));
const measurements = { initialJsGzipBytes, lazyChunks };
const result = evaluateBundleBudget(measurements, budgets);
const fixtures = [
  {
    name: "initial-js-over-budget",
    passed:
      !evaluateBundleBudget(
        {
          initialJsGzipBytes: budgets.initialJsGzipBytes + 1,
          lazyChunks: [],
        },
        budgets,
      ).passed,
  },
  {
    name: "lazy-chunk-over-budget",
    passed:
      !evaluateBundleBudget(
        {
          initialJsGzipBytes: 0,
          lazyChunks: [
            {
              path: "fixture.js",
              gzipBytes: budgets.lazyChunkGzipBytes + 1,
            },
          ],
        },
        budgets,
      ).passed,
  },
];
const passed =
  result.passed &&
  fixtures.every((fixture) => fixture.passed) &&
  classification.missingImports.length === 0 &&
  missingOutputs.length === 0;
const completedReport = {
  ...report,
  measurements,
  classification,
  missingOutputs,
  thresholds: budgets,
  results: result,
  fixtures,
  passed,
};

await writeFile(
  "artifacts/performance/bundle.json",
  `${JSON.stringify(completedReport, null, 2)}\n`,
);
if (!passed) {
  process.stderr.write(
    `Bundle budget or manifest integrity failed: ${[
      ...classification.missingImports,
      ...missingOutputs,
    ].join(", ")}\n`,
  );
  process.exit(1);
}
process.stdout.write(
  `Bundle budget: PASS (initial JS ${initialJsGzipBytes} / ${budgets.initialJsGzipBytes} gzip bytes)\n`,
);