#!/usr/bin/env node
/**
 * Build one Node zip per Lambda key. Used by deploy.yaml.
 * Each zip is functions/<name>/<sha>.zip on S3. GIT_SHA is written to
 * src/buildInfo.js inside the zip so a deploy is identifiable without a
 * Terraform-owned env var.
 */
import { spawn, spawnSync } from "node:child_process";
import { cpSync, existsSync, mkdirSync, mkdtempSync, rmSync, writeFileSync } from "node:fs";
import { tmpdir } from "node:os";
import { join, resolve } from "node:path";
import { fileURLToPath } from "node:url";

const ROOT = fileURLToPath(new URL("..", import.meta.url));

const FUNCTIONS = [
  "process_csv",
  "slack_app_home",
  "fetch_boa",
  "expense_receiver",
  "expense_processor",
];

function parseArgs(argv) {
  const out = { gitSha: "", outDir: join(ROOT, "build", "packages"), only: [] };
  for (let i = 0; i < argv.length; i += 1) {
    const arg = argv[i];
    if (arg === "--git-sha") {
      out.gitSha = argv[++i];
    } else if (arg === "--out-dir") {
      out.outDir = resolve(argv[++i]);
    } else if (arg === "--only") {
      out.only.push(argv[++i]);
    } else {
      throw new Error(`unknown argument: ${arg}`);
    }
  }
  if (!out.gitSha) {
    throw new Error("--git-sha is required");
  }
  return out;
}

function zipDir(srcDir, zipPath) {
  return new Promise((resolve, reject) => {
    const child = spawn("zip", ["-qr", zipPath, "."], { cwd: srcDir, stdio: "inherit" });
    child.on("exit", (code) => {
      if (code === 0) resolve();
      else reject(new Error(`zip exited ${code}`));
    });
  });
}

async function build(name, gitSha, outDir) {
  const dest = mkdtempSync(join(tmpdir(), `payments-${name}-`));
  try {
    cpSync(join(ROOT, "src"), join(dest, "src"), { recursive: true });
    cpSync(join(ROOT, "package.json"), join(dest, "package.json"));
    if (existsSync(join(ROOT, "package-lock.json"))) {
      cpSync(join(ROOT, "package-lock.json"), join(dest, "package-lock.json"));
    }
    writeFileSync(
      join(dest, "src", "buildInfo.js"),
      `export const GIT_SHA = ${JSON.stringify(gitSha)};\n`,
      "utf8",
    );
    const npm = spawnSync("npm", ["ci", "--omit=dev"], { cwd: dest, stdio: "inherit" });
    if (npm.status !== 0) {
      throw new Error("npm ci --omit=dev failed");
    }
    mkdirSync(outDir, { recursive: true });
    const zipPath = resolve(outDir, `${name}.zip`);
    rmSync(zipPath, { force: true });
    await zipDir(dest, zipPath);
    return zipPath;
  } finally {
    rmSync(dest, { recursive: true, force: true });
  }
}

const args = parseArgs(process.argv.slice(2));
const selected = args.only.length ? args.only : FUNCTIONS;
const unknown = selected.filter((name) => !FUNCTIONS.includes(name));
if (unknown.length) {
  console.error(`unknown function keys: ${unknown.join(", ")}`);
  process.exit(2);
}

for (const name of selected) {
  const path = await build(name, args.gitSha, args.outDir);
  console.log(path);
}