import fs from 'node:fs';
import os from 'node:os';
import path from 'node:path';
import https from 'node:https';
import {execFileSync} from 'node:child_process';
import {fileURLToPath} from 'node:url';

const __dirname = path.dirname(fileURLToPath(import.meta.url));

const VERSION = '3.8.1';
const BASE_URL = 'https://download.kiwix.org/release/kiwix-tools';
const PLATFORM_MAP = {linux: 'linux', darwin: 'macos', win32: 'win'};

const BIN_DIR = path.join(__dirname, '..', 'bin'); // project root/bin

/** Download a file, following redirects. */
function download(url, dest) {
	return new Promise((resolve, reject) => {
		const file = fs.createWriteStream(dest);
		https.get(url, res => {
			if (res.statusCode >= 300 && res.statusCode < 400 && res.headers.location) {
				file.close();
				return resolve(download(res.headers.location, dest));
			}
			if (!res.statusCode || res.statusCode >= 400) {
				return reject(new Error(`Download failed: ${res.statusCode} ${res.statusMessage}`));
			}
			res.pipe(file);
			file.on('finish', () => file.close(resolve));
		}).on('error', err => fs.unlink(dest, () => reject(err)));
	});
}

/** Recursively search a directory for a file by name. */
function findFile(dir, name) {
	for (const entry of fs.readdirSync(dir, {withFileTypes: true})) {
		const full = path.join(dir, entry.name);
		if (entry.isDirectory()) {
			const found = findFile(full, name);
			if (found) return found;
		} else if (entry.name === name) {
			return full;
		}
	}
	return null;
}

async function downloadAndExtract() {
	const platformName = PLATFORM_MAP[process.platform];
	if (!platformName) throw new Error(`Unsupported platform: ${process.platform}`);

	const ext = platformName === 'win' ? 'zip' : 'tar.gz';
	const archiveName = `kiwix-tools_${platformName}-x86_64-${VERSION}.${ext}`;
	const url = `${BASE_URL}/${archiveName}`;
	const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'kiwix-tools-'));
	const archivePath = path.join(tmpDir, archiveName);

	console.log('Downloading kiwix-tools from:', url);
	await download(url, archivePath);

	console.log('Extracting...');
	execFileSync('tar', ['-xf', archivePath, '-C', tmpDir]); // bsdtar handles zip too

	await fs.promises.mkdir(BIN_DIR, {recursive: true});

	// Copy the binary plus any DLLs sitting alongside it (Windows deps)
	for (const entry of await fs.promises.readdir(tmpDir)) {
		if(!/\.(tar|gz|zip)$/.test(entry)) await fs.promises.copyFile(path.join(tmpDir, entry), path.join(BIN_DIR, entry));
		if(process.platform !== 'win32') await fs.promises.chmod(BIN_DIR, 0o755, {recursive: true});
	}

	await fs.promises.rm(tmpDir, {recursive: true, force: true});
	console.log('Installed to:', BIN_DIR);
}

downloadAndExtract().catch(err => {
	console.error(err);
	process.exit(1)
}).finally(() => process.exit());