import etag from 'etag';

import getContentTypeHeader from '../utils/getContentTypeHeader.js';

import rewriteBareModuleIdentifiers from '../utils/rewriteBareModuleIdentifiers.js';

export default function serveJavaScriptModule(req, res) {

try {

const code = rewriteBareModuleIdentifiers(

req.entry.content.toString('utf8'),

req.packageConfig

);

res

.set({

'Cross-Origin-Resource-Policy': 'cross-origin',

'Content-Length': Buffer.byteLength(code),

'Content-Type': getContentTypeHeader(req.entry.contentType),

'Cache-Control': 'public, max-age=31536000', // 1 year

ETag: etag(code),

'Cache-Tag': 'file, js-file, js-module'

})

.send(code);

} catch (error) {

console.error(error);

const errorName = error.constructor.name;

const errorMessage = error.message.replace(

/^.*?\/unpkg-.+?\//,

`/${req.packageSpec}/`

);

const codeFrame = error.codeFrame;

const debugInfo = `${errorName}: ${errorMessage}\n\n${codeFrame}`;

res

.status(500)

.type('text')

.send(

`Cannot generate module for ${req.packageSpec}${req.filename}\n\n${debugInfo}`

);

}

}