const decoder = new TextDecoder();
const denoJson = JSON.parse(await Deno.readTextFile("deno.json"));
let version = denoJson.version;
if (!version) {
  console.error("Missing 'version' in deno.json");
  Deno.exit(1);
}

const branch = Deno.env.get("GITHUB_REF")?.replace("refs/heads/", "") ?? "";
console.log(`Branch: ${branch}`);
if (branch.startsWith("prerelease-")) {
  const suffix = branch.replace("prerelease-", "");
  const base = version.split("-")[0];
  const expected = `${base}-${suffix}`;
  if (version !== expected) {
    denoJson.version = expected;
    await Deno.writeTextFile("deno.json", JSON.stringify(denoJson, null, 2));
    await run("git", ["config", "user.name", "CI"]);
    await run("git", ["config", "user.email", "ci@cyborggrizzly.com"]);
    await run("git", ["add", "deno.json"]);
    await run("git", [
      "commit",
      "-m",
      `fix: sync version with branch ${branch}`,
    ]);
    await run("git", ["push"]);
    version = expected;
  }
}

const tag = `v${version}`;
try {
  await run("git", ["rev-parse", tag]);
  console.log(`Tag ${tag} already exists.`);
} catch {
  await run("git", ["tag", tag]);
  await run("git", ["push", "origin", tag]);
}

async function run(cmd: string, args: string[]) {
  const command = new Deno.Command(cmd, {
    args,
    stdout: "piped",
    stderr: "piped",
  });
  const status = await command.output();
  if (!status.success) {
    const err = decoder.decode(await status.stderr);
    throw new Error(`Command failed: ${cmd} ${args.join(" ")}\n${err}`);
  }
}