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

const __dirname = path.dirname(fileURLToPath(import.meta.url));
const rootDir = path.resolve(__dirname, '..');
const distDir = path.join(rootDir, 'dist');
const srcDir = path.join(rootDir, 'src');
const configPath = path.join(rootDir, 'sea-config.json');
const payloadPath = path.join(distDir, 'app-payload.bin');

// Ensure dist directory exists
if (!fs.existsSync(distDir)) {
    fs.mkdirSync(distDir, { recursive: true });
}

console.log('Packaging application code into SEA payload...');

function packDirectory(dir, baseDir = dir) {
    const result = {};
    for (const entry of fs.readdirSync(dir, { withFileTypes: true })) {
        const full = path.join(dir, entry.name);
        const rel = path.relative(baseDir, full);
        if (entry.isDirectory()) {
            Object.assign(result, packDirectory(full, baseDir));
        } else if (entry.isFile()) {
            result[rel] = fs.readFileSync(full).toString('base64');
        }
    }
    return result;
}

// Pack src/ and package.json
const payload = packDirectory(srcDir);
const pkgPath = path.join(rootDir, 'package.json');
if (fs.existsSync(pkgPath)) {
    payload['package.json'] = fs.readFileSync(pkgPath).toString('base64');
}

const compressedPayload = zlib.deflateSync(Buffer.from(JSON.stringify(payload)));
fs.writeFileSync(payloadPath, compressedPayload);

console.log(`Packed ${Object.keys(payload).length} files (${(compressedPayload.length / 1024 / 1024).toFixed(2)} MB compressed)`);

// Prepare sea-config.json with payload asset
const config = {
    main: 'src/sea-entry.cjs',
    output: 'dist/dashback',
    assets: {
        'app-payload.bin': 'dist/app-payload.bin',
    },
    disableExperimentalSEAWarning: true,
};

fs.writeFileSync(configPath, JSON.stringify(config, null, 2) + '\n');

console.log('Generating Single Executable Application (SEA)...');
try {
    execFileSync(process.execPath, ['--build-sea', 'sea-config.json'], {
        cwd: rootDir,
        stdio: 'inherit',
    });

    const outputPath = path.join(distDir, 'dashback');
    if (process.platform !== 'win32' && fs.existsSync(outputPath)) {
        fs.chmodSync(outputPath, 0o755);
    }

    console.log(`\nSuccessfully built standalone SEA: ${path.relative(rootDir, outputPath)}`);
} catch (err) {
    console.error('\nFailed to build SEA:', err.message);
    process.exit(1);
}