// cal like this in your resolvers
const { filename, createReadStream } = await photo.promise

// helper file upload
const { resolve } = require('path')

const uploadFile = ({ filename, stream }) => {
    let linux = '/tmp'
    let window = process.env.TEMP || ''

    if (process.platform !== 'win32') {
        stream.pipe(createWriteStream(resolve(process.cwd(), `${linux}/${filename}`)))
    } else {
        stream.pipe(createWriteStream(resolve(process.cwd(), `${window}/${filename}`)))
    }
}

const validateFile = ({ filename, stream }) => {
    const extFile = filename.replace('.', '')
    const extPattern = /(jpg|jpeg|png|gif)/gi.test(extFile)

    if (!extPattern) throw new TypeError('Image format is not valid')
    else return uploadFile({ filename, stream })
}

export const fileUpload = ({ filename, stream }) =>
    filename ? validateFile({ filename, stream }) : new Error('Image is required')