import defaultConfig from './config-default'

/**

* Provides functionality for signing up with a Solid provider

* @module signup

*/

/**

* Creates a Signup UI manager

* @class

*/

export function Signup (config) {

this.config = config || defaultConfig

}

/**

* Sets up an event listener to monitor login messages from child window/iframe

* @method listen

* @return {Promise<String>} Event listener promise, resolves to user's WebID

*/

Signup.prototype.listen = function listen () {

const promise = new Promise(function (resolve, reject) {

const eventMethod = window.addEventListener

? 'addEventListener'

: 'attachEvent'

const eventListener = window[eventMethod]

const messageEvent = eventMethod === 'attachEvent'

? 'onmessage'

: 'message'

eventListener(messageEvent, function (e) {

const u = e.data

if (u.slice(0, 5) === 'User:') {

const user = u.slice(5, u.length)

if (user && user.length > 0 && user.slice(0, 4) === 'http') {

return resolve(user)

} else {

return reject(user)

}

}

}, true)

})

return promise

}

/**

* Opens a signup popup window, sets up `listen()`.

* @method signup

* @static

* @param signupUrl {String} Location of a Solid server for user signup.

* @return {Promise<String>} Returns a listener promise, resolves with signed

* up user's WebID.

*/

Signup.prototype.signup = function signup (signupUrl) {

signupUrl = signupUrl || this.config.signupEndpoint

const width = this.config.signupWindowWidth

const height = this.config.signupWindowHeight

// set borders

const leftPosition = (window.screen.width / 2) - ((width / 2) + 10)

// set title and status bars

const topPosition = (window.screen.height / 2) - ((height / 2) + 50)

const windowTitle = 'Solid signup'

const windowUrl = signupUrl + '?origin=' +

encodeURIComponent(window.location.origin)

const windowSpecs = 'resizable,scrollbars,status,width=' + width + ',height=' +

height + ',left=' + leftPosition + ',top=' + topPosition

window.open(windowUrl, windowTitle, windowSpecs)

const self = this

return new Promise(function (resolve) {

self.listen()

.then(function (webid) {

return resolve(webid)

})

})

}