/**
 * Build-time CLI: определяет upstream-релиз Hysteria и печатает env-строки.
 *
 * Запускается только на build machine из tools/build/lib/hysteria.sh.
 * Target-сервер этот код никогда не выполняет.
 *
 *   bun run tools/resolve-hysteria.ts --channel stable
 *   bun run tools/resolve-hysteria.ts --channel stable --version v2.12.2
 */

import {
  HYSTERIA_UPSTREAM_REPO,
  selectLatestStableRelease,
  selectReleaseByVersion,
  type GithubRelease,
  type ResolvedHysteriaRelease
} from "../src/build/hysteriaRelease";

const RELEASES_PER_PAGE = 100;
const MAX_PAGES = 5;

function fail(message: string): never {
  console.error(`[hy2xs-build] ERROR: ${message}`);
  process.exit(1);
}

function parseArgs(argv: string[]): { channel: string; version: string } {
  let channel = "stable";
  let version = "";

  for (let i = 0; i < argv.length; i += 1) {
    const arg = argv[i];
    if (arg === "--channel") {
      channel = argv[i + 1] ?? "";
      i += 1;
      continue;
    }
    if (arg === "--version") {
      version = argv[i + 1] ?? "";
      i += 1;
      continue;
    }
    fail(`unknown argument: ${arg}`);
  }

  if (channel !== "stable") {
    fail(`unsupported HYSTERIA_CHANNEL for resolution: ${channel} (expected stable)`);
  }

  return { channel, version: version.trim() };
}

async function fetchReleases(): Promise<GithubRelease[]> {
  const headers: Record<string, string> = {
    Accept: "application/vnd.github+json",
    "X-GitHub-Api-Version": "2022-11-28",
    "User-Agent": "hy2xs-build"
  };

  const token = (process.env.GITHUB_TOKEN ?? "").trim();
  if (token) {
    headers.Authorization = `Bearer ${token}`;
  }

  const releases: GithubRelease[] = [];

  for (let page = 1; page <= MAX_PAGES; page += 1) {
    const url = `https://api.github.com/repos/${HYSTERIA_UPSTREAM_REPO}/releases?per_page=${RELEASES_PER_PAGE}&page=${page}`;
    const response = await fetch(url, { headers });

    if (response.status === 403 || response.status === 429) {
      fail(
        `GitHub API rate limit reached (HTTP ${response.status}). ` +
          "Set GITHUB_TOKEN, or build with HYSTERIA_CHANNEL=pinned."
      );
    }
    if (!response.ok) {
      fail(`GitHub API request failed: HTTP ${response.status} for ${url}`);
    }

    const payload = (await response.json()) as unknown;
    if (!Array.isArray(payload)) {
      fail(`unexpected GitHub API payload for ${url}`);
    }

    releases.push(...(payload as GithubRelease[]));

    if (payload.length < RELEASES_PER_PAGE) {
      break;
    }
  }

  if (releases.length === 0) {
    fail(`no releases returned for ${HYSTERIA_UPSTREAM_REPO}`);
  }

  return releases;
}

function emit(resolved: ResolvedHysteriaRelease, resolution: string): void {
  // Значения читаются bash через eval-free парсинг, поэтому печатаем по строке.
  console.log(`HYSTERIA_VERSION=${resolved.version}`);
  console.log(`HYSTERIA_TAG=${resolved.tag}`);
  console.log(`HYSTERIA_ARTIFACT_URL=${resolved.artifactUrl}`);
  console.log(`HYSTERIA_HASHES_URL=${resolved.hashesUrl}`);
  console.log(`HYSTERIA_PUBLISHED_AT=${resolved.publishedAt}`);
  console.log(`HYSTERIA_RESOLUTION=${resolution}`);
}

async function main(): Promise<void> {
  const { version } = parseArgs(Bun.argv.slice(2));
  const releases = await fetchReleases();

  try {
    if (version) {
      emit(selectReleaseByVersion(releases, version), "override");
      return;
    }
    emit(selectLatestStableRelease(releases), "latest-stable");
  } catch (error) {
    fail(error instanceof Error ? error.message : String(error));
  }
}

await main();