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

export function matchReports(request) {
  const [a, b] = request.reports ?? [];
  if (
    !a ||
    !b ||
    a.workerId !== "worker-a" ||
    b.workerId !== "worker-b" ||
    a.imageDigest === b.imageDigest ||
    a.toolchain === b.toolchain ||
    a.inputDigest !== b.inputDigest ||
    a.checkId !== b.checkId ||
    a.normalizedOutputDigest !== b.normalizedOutputDigest ||
    JSON.stringify(a.normalizedMembers) !==
      JSON.stringify(b.normalizedMembers) ||
    a.verdict !== "pass" ||
    b.verdict !== "pass"
  )
    throw new Error("Independent worker evidence does not agree and pass.");
  const rules = request.rules;
  if (!Array.isArray(rules) || rules.length === 0)
    throw new Error("Matcher rules are required.");
  const appliedRuleIds = rules
    .map((rule) => rule.id)
    .sort((left, right) => Buffer.from(left).compare(Buffer.from(right)));
  if (
    new Set(appliedRuleIds).size !== appliedRuleIds.length ||
    rules.some((rule) => !Array.isArray(rule.deniedMemberDigests))
  )
    throw new Error("Matcher rules are invalid.");
  const denied = new Set(rules.flatMap((rule) => rule.deniedMemberDigests));
  if (a.normalizedMembers.some((member) => denied.has(member)))
    throw new Error("Privacy rule matched normalized evidence.");
  return {
    schema: "portfolio-privacy-matcher-result/v1",
    inputDigest: a.inputDigest,
    checkId: a.checkId,
    normalizedOutputDigest: a.normalizedOutputDigest,
    normalizedMembers: a.normalizedMembers,
    ruleSetDigest: request.ruleSetDigest,
    appliedRuleIds,
    verdict: "pass",
    workerImageDigests: [a.imageDigest, b.imageDigest],
  };
}

async function main() {
  const result = matchReports(
    JSON.parse(await readFile("/input/request.json", "utf8")),
  );
  await writeFile("/output/result.json", JSON.stringify(result), {
    flag: "wx",
    mode: 0o400,
  });
}

if (process.argv[1] && import.meta.url === pathToFileURL(process.argv[1]).href)
  await main();