#!/usr/bin/env node
import { createHash } from "node:crypto";
import {
  access,
  lstat,
  mkdir,
  mkdtemp,
  readFile,
  readdir,
  rename,
  rm,
  writeFile,
} from "node:fs/promises";
import path from "node:path";
import { deflateRawSync } from "node:zlib";
import { fileURLToPath } from "node:url";

const root = path.resolve(path.dirname(fileURLToPath(import.meta.url)), "..");
const packageJson = JSON.parse(
  await readFile(path.join(root, "package.json"), "utf8"),
);
const input = path.join(root, "dist");
const argument = (name, fallback) => {
  const index = process.argv.indexOf(name);
  return index >= 0 ? process.argv[index + 1] : fallback;
};
const output = path.resolve(
  root,
  argument("--output", `release/svg-tools-${packageJson.version}.zip`),
);
const checksumOutput = `${output}.sha256`;
const force = process.argv.includes("--force");

if (path.extname(output).toLowerCase() !== ".zip") {
  throw new Error("Release output must use a .zip extension");
}
if (output === path.parse(output).root || output === root) {
  throw new Error("Release output is not a safe file target");
}

const exists = (file) =>
  access(file).then(
    () => true,
    () => false,
  );
if (!force && (await exists(output))) {
  throw new Error(`Release already exists (use --force): ${output}`);
}
if (!force && (await exists(checksumOutput))) {
  throw new Error(`Checksum already exists (use --force): ${checksumOutput}`);
}

const required = [
  "index.html",
  "toolbox-app.json",
  "favicon.svg",
  "canvas-frame-controller.js",
  "README.md",
  "CHANGELOG.md",
  "LICENSE",
  "SOURCE.md",
  "THIRD_PARTY_NOTICES.md",
  "THIRD_PARTY_LICENSES.txt",
  "LICENSES/README.md",
  "LICENSES/npm-runtime-licenses.txt",
];
for (const name of required) {
  const details = await lstat(path.join(input, name)).catch(() => null);
  if (!details?.isFile() || details.isSymbolicLink()) {
    throw new Error(`Release input is missing a regular file: ${name}`);
  }
}
const assets = await lstat(path.join(input, "assets")).catch(() => null);
if (!assets?.isDirectory() || assets.isSymbolicLink()) {
  throw new Error("Release input is missing its assets directory");
}

const manifest = JSON.parse(
  await readFile(path.join(input, "toolbox-app.json"), "utf8"),
);
if (
  manifest.id !== "de.add-ideas.svg-tools" ||
  manifest.version !== packageJson.version ||
  manifest.entry !== "./" ||
  manifest.icon !== "./favicon.svg" ||
  !manifest.assets?.includes("./canvas-frame-controller.js")
) {
  throw new Error("Packaged Toolbox manifest identity/assets are invalid");
}

async function collect(directory, prefix = "") {
  const files = [];
  for (const entry of (await readdir(directory, { withFileTypes: true })).sort(
    (left, right) =>
      left.name < right.name ? -1 : left.name > right.name ? 1 : 0,
  )) {
    const absolute = path.join(directory, entry.name);
    const relative = prefix ? `${prefix}/${entry.name}` : entry.name;
    if (entry.isSymbolicLink()) {
      throw new Error(`Release input contains a symbolic link: ${relative}`);
    }
    if (entry.isDirectory()) files.push(...(await collect(absolute, relative)));
    else if (entry.isFile()) files.push({ absolute, relative });
    else throw new Error(`Unsupported release entry: ${relative}`);
  }
  return files;
}

const files = await collect(input);
if (files.length > 65_535) throw new Error("Release contains too many files");
for (const { relative } of files) {
  if (
    relative.endsWith(".map") ||
    /(?:^|\/)(?:\.env(?:\.|$)|id_rsa|id_ed25519|.*\.pem$|.*\.key$)/iu.test(
      relative,
    )
  ) {
    throw new Error(`Forbidden release entry: ${relative}`);
  }
  if (relative.startsWith("/") || relative.split("/").includes("..")) {
    throw new Error(`Unsafe release entry: ${relative}`);
  }
}

const indexHtml = await readFile(path.join(input, "index.html"), "utf8");
if (/\b(?:src|href)=["']\//iu.test(indexHtml)) {
  throw new Error("index.html contains a root-absolute asset reference");
}

const crcTable = new Uint32Array(256);
for (let index = 0; index < 256; index += 1) {
  let value = index;
  for (let bit = 0; bit < 8; bit += 1) {
    value = value & 1 ? 0xedb88320 ^ (value >>> 1) : value >>> 1;
  }
  crcTable[index] = value >>> 0;
}
function crc32(bytes) {
  let value = 0xffffffff;
  for (const byte of bytes)
    value = crcTable[(value ^ byte) & 0xff] ^ (value >>> 8);
  return (value ^ 0xffffffff) >>> 0;
}
function header(length) {
  return Buffer.alloc(length);
}

const localParts = [];
const centralParts = [];
let offset = 0;
for (const file of files) {
  const source = await readFile(file.absolute);
  const compressed = deflateRawSync(source, { level: 9 });
  const name = Buffer.from(file.relative, "utf8");
  const checksum = crc32(source);
  if (
    source.byteLength > 0xffffffff ||
    compressed.byteLength > 0xffffffff ||
    offset > 0xffffffff
  ) {
    throw new Error("ZIP64 releases are not supported");
  }

  const local = header(30);
  local.writeUInt32LE(0x04034b50, 0);
  local.writeUInt16LE(20, 4);
  local.writeUInt16LE(0x0800, 6);
  local.writeUInt16LE(8, 8);
  local.writeUInt16LE(0, 10);
  local.writeUInt16LE(0x0021, 12);
  local.writeUInt32LE(checksum, 14);
  local.writeUInt32LE(compressed.byteLength, 18);
  local.writeUInt32LE(source.byteLength, 22);
  local.writeUInt16LE(name.byteLength, 26);
  local.writeUInt16LE(0, 28);
  localParts.push(local, name, compressed);

  const central = header(46);
  central.writeUInt32LE(0x02014b50, 0);
  central.writeUInt16LE(0x0314, 4);
  central.writeUInt16LE(20, 6);
  central.writeUInt16LE(0x0800, 8);
  central.writeUInt16LE(8, 10);
  central.writeUInt16LE(0, 12);
  central.writeUInt16LE(0x0021, 14);
  central.writeUInt32LE(checksum, 16);
  central.writeUInt32LE(compressed.byteLength, 20);
  central.writeUInt32LE(source.byteLength, 24);
  central.writeUInt16LE(name.byteLength, 28);
  central.writeUInt16LE(0, 30);
  central.writeUInt16LE(0, 32);
  central.writeUInt16LE(0, 34);
  central.writeUInt16LE(0, 36);
  central.writeUInt32LE((0o100644 << 16) >>> 0, 38);
  central.writeUInt32LE(offset, 42);
  centralParts.push(central, name);
  offset += local.byteLength + name.byteLength + compressed.byteLength;
}
const centralOffset = offset;
const centralSize = centralParts.reduce(
  (sum, part) => sum + part.byteLength,
  0,
);
if (centralOffset + centralSize > 0xffffffff) {
  throw new Error("ZIP64 releases are not supported");
}
const end = header(22);
end.writeUInt32LE(0x06054b50, 0);
end.writeUInt16LE(0, 4);
end.writeUInt16LE(0, 6);
end.writeUInt16LE(files.length, 8);
end.writeUInt16LE(files.length, 10);
end.writeUInt32LE(centralSize, 12);
end.writeUInt32LE(centralOffset, 16);
end.writeUInt16LE(0, 20);
const archive = Buffer.concat([...localParts, ...centralParts, end]);

await mkdir(path.dirname(output), { recursive: true });
const staging = await mkdtemp(path.join(path.dirname(output), ".svg-release-"));
const stagedArchive = path.join(staging, path.basename(output));
const stagedChecksum = `${stagedArchive}.sha256`;
try {
  await writeFile(stagedArchive, archive, { flag: "wx", mode: 0o644 });
  const digest = createHash("sha256").update(archive).digest("hex");
  await writeFile(stagedChecksum, `${digest}  ${path.basename(output)}\n`, {
    flag: "wx",
    mode: 0o644,
  });
  if (force) {
    await rm(output, { force: true });
    await rm(checksumOutput, { force: true });
  }
  await rename(stagedArchive, output);
  await rename(stagedChecksum, checksumOutput);
  process.stdout.write(
    `Created ${path.relative(root, output)} (${archive.byteLength} bytes, ${files.length} files)\nSHA-256 ${digest}\n`,
  );
} finally {
  await rm(staging, { recursive: true, force: true });
}