module.exports = copy

const debug = require('./debug')

const fs = require('fs')

const mkdirp = require('fs-extra').mkdirp

const error = require('./http-error')

const path = require('path')

const http = require('http')

const https = require('https')

const getContentType = require('./utils').getContentType

/**

* Cleans up a file write stream (ends stream, deletes the file).

* @method cleanupFileStream

* @private

* @param stream {WriteStream}

*/

function cleanupFileStream (stream) {

const streamPath = stream.path

stream.destroy()

fs.unlinkSync(streamPath)

}

/**

* Performs an LDP Copy operation, imports a remote resource to a local path.

* @param resourceMapper {ResourceMapper} A resource mapper instance.

* @param copyToUri {Object} The location (in the current domain) to copy to.

* @param copyFromUri {String} Location of remote resource to copy from

* @return A promise resolving when the copy operation is finished

*/

function copy (resourceMapper, copyToUri, copyFromUri) {

return new Promise((resolve, reject) => {

const request = /^https:/.test(copyFromUri) ? https : http

request.get(copyFromUri)

.on('error', function (err) {

debug.handlers('COPY -- Error requesting source file: ' + err)

this.end()

return reject(new Error('Error writing data: ' + err))

})

.on('response', function (response) {

if (response.statusCode !== 200) {

debug.handlers('COPY -- HTTP error reading source file: ' + response.statusMessage)

this.end()

const error = new Error('Error reading source file: ' + response.statusMessage)

error.statusCode = response.statusCode

return reject(error)

}

// Grab the content type from the source

const contentType = getContentType(response.headers)

resourceMapper.mapUrlToFile({ url: copyToUri, createIfNotExists: true, contentType })

.then(({ path: copyToPath }) => {

mkdirp(path.dirname(copyToPath), function (err) {

if (err) {

debug.handlers('COPY -- Error creating destination directory: ' + err)

return reject(new Error('Failed to create the path to the destination resource: ' + err))

}

const destinationStream = fs.createWriteStream(copyToPath)

.on('error', function (err) {

cleanupFileStream(this)

return reject(new Error('Error writing data: ' + err))

})

.on('finish', function () {

// Success

debug.handlers('COPY -- Wrote data to: ' + copyToPath)

resolve()

})

response.pipe(destinationStream)

})

})

.catch(() => reject(error(500, 'Could not find target file to copy')))

})

})

}