const stream = require('stream');

const webpackHot = require('webpack-hot-middleware');

const PassThrough = stream.PassThrough;

module.exports = ({compiler, others}) => {

    const middleware = webpackHot(compiler, others);

    return async (ctx, next) => {

        const res = Object.assign({}, ctx.res);

        const streamInstance = new PassThrough();

        streamInstance.on('data', chunk => {

            if(chunk && global.cache &&global.cache.updateCache){

                global.cache.updateCache();

            }

        });

        ctx.body = streamInstance;

        await middleware(

            ctx.req,

            Object.assign(res, {

                write: streamInstance.write.bind(streamInstance),

                writeHead: (

                    status ,

                    headers,

                ) => {

                    ctx.status = status;

                    ctx.set(headers);

                },

                end: (content) => {

                    ctx.body = content || 'devMiddleWare no body';

                },

            }),

            next

        )

    }

}