#!/usr/bin/env node
import { cpSync, existsSync, mkdirSync, readFileSync, rmSync, writeFileSync } from "node:fs";
import path from "node:path";
import { spawnSync } from "node:child_process";

import {
  bundleName,
  bundleRoot,
  getNpmCommand,
  nodecgRuntimeNodeModules,
  nodecgRuntimeRoot,
  preparedBundleEntries,
  requiredPreparedBundleEntries,
  runtimeBundleRoot,
  runtimeNpmCache,
} from "./build-config.mjs";

function readJson(filePath) {
  return JSON.parse(readFileSync(filePath, "utf8"));
}

function copyIfExists(source, destination) {
  if (!existsSync(source)) {
    return false;
  }

  cpSync(source, destination, {
    recursive: true,
    force: true,
    dereference: true,
    filter: (sourcePath) => !sourcePath.split(path.sep).includes("node_modules"),
  });
  return true;
}

function run(command, args, cwd) {
  const result = spawnSync(command, args, {
    cwd,
    stdio: "inherit",
    shell: process.platform === "win32",
    env: {
      ...process.env,
      npm_config_cache: runtimeNpmCache,
    },
  });

  if (result.error) {
    throw new Error(`${command} ${args.join(" ")} failed: ${result.error.message}`);
  }

  if (result.status !== 0) {
    throw new Error(`${command} ${args.join(" ")} failed with code ${result.status}`);
  }
}

function getInstalledNodecgVersion() {
  const nodecgPackagePath = path.join(bundleRoot, "node_modules", "nodecg", "package.json");

  if (!existsSync(nodecgPackagePath)) {
    throw new Error(
      [
        "NodeCG is not installed in the parent project.",
        `Expected: ${nodecgPackagePath}`,
        `Run 'pnpm install' from ${bundleRoot} before packaging.`,
      ].join("\n"),
    );
  }

  return readJson(nodecgPackagePath).version;
}

function assertBundleBuildExists() {
  for (const entry of requiredPreparedBundleEntries) {
    const source = path.join(bundleRoot, entry);
    if (!existsSync(source)) {
      throw new Error(
        [
          `The built Scoreko bundle is missing '${entry}'.`,
          `Expected: ${source}`,
          `Run 'pnpm build' from ${bundleRoot} before packaging.`,
        ].join("\n"),
      );
    }
  }
}

function createRuntimePackageJson() {
  const bundlePackageJson = readJson(path.join(bundleRoot, "package.json"));
  const dependencies = {
    nodecg: getInstalledNodecgVersion(),
    ...(bundlePackageJson.dependencies ?? {}),
  };

  writeFileSync(
    path.join(nodecgRuntimeRoot, "package.json"),
    `${JSON.stringify(
      {
        private: true,
        name: "scoreko-nodecg-runtime",
        version: bundlePackageJson.version ?? "0.0.0",
        description: "Packaged NodeCG runtime for Scoreko Desktop.",
        type: "commonjs",
        scripts: {
          start: "node index.js",
        },
        dependencies,
      },
      null,
      2,
    )}\n`,
  );

  writeFileSync(path.join(nodecgRuntimeRoot, "index.js"), 'require("nodecg");\n');
}

function copyBundle() {
  mkdirSync(runtimeBundleRoot, { recursive: true });

  for (const entry of preparedBundleEntries) {
    copyIfExists(path.join(bundleRoot, entry), path.join(runtimeBundleRoot, entry));
  }
}

function writeManifest() {
  const bundlePackageJson = readJson(path.join(bundleRoot, "package.json"));
  const runtimePackageJson = readJson(path.join(nodecgRuntimeRoot, "package.json"));

  writeFileSync(
    path.join(nodecgRuntimeRoot, ".scoreko-runtime.json"),
    `${JSON.stringify(
      {
        bundleName,
        bundleVersion: bundlePackageJson.version ?? "0.0.0",
        nodecgVersion: runtimePackageJson.dependencies.nodecg,
        generatedAt: new Date().toISOString(),
      },
      null,
      2,
    )}\n`,
  );
}

function installRuntimeDependencies() {
  if (process.env.SCOREKO_SKIP_RUNTIME_NPM_INSTALL === "1") {
    console.log("[prepare-runtime] Skipping runtime npm install by environment request.");
    return;
  }

  run(getNpmCommand(), ["install", "--omit=dev", "--no-audit", "--no-fund"], nodecgRuntimeRoot);
}

function main() {
  assertBundleBuildExists();

  rmSync(nodecgRuntimeRoot, { recursive: true, force: true });
  mkdirSync(nodecgRuntimeNodeModules, { recursive: true });
  mkdirSync(path.join(nodecgRuntimeRoot, "bundles"), { recursive: true });

  createRuntimePackageJson();
  copyBundle();
  installRuntimeDependencies();
  writeManifest();

  console.log(`[prepare-runtime] NodeCG runtime ready at ${nodecgRuntimeRoot}`);
}

try {
  main();
} catch (error) {
  console.error(error instanceof Error ? error.message : error);
  process.exit(1);
}