FileSaver_Lib

FileSaver library

This script should not be not be installed directly. It is a library for other scripts to include with the meta directive // @require https://greasyfork.org/scripts/387124-filesaver-lib/code/FileSaver_Lib.js?version=715484

// ==UserScript==
// @name          FileSaver_Lib
// @namespace     https://www.douban.com/people/57965364/FileSaver
// @description   FileSaver library
// @include       *
// @match         *
// @version       0.0.2
// ==/UserScript==

/*
* FileSaver.js
* A saveAs() FileSaver implementation.
*
* By Eli Grey, http://eligrey.com
*
* License : https://github.com/eligrey/FileSaver.js/blob/master/LICENSE.md (MIT)
* source  : http://purl.eligrey.com/github/FileSaver.js
*/

// The one and only way of getting global scope in all environments
// https://stackoverflow.com/q/3277182/1008999
var _global = typeof window === 'object' && window.window === window
	? window : typeof self === 'object' && self.self === self
		? self : typeof global === 'object' && global.global === global
			? global
			: this

function bom(blob, opts) {
	if (typeof opts === 'undefined') opts = { autoBom: false }
	else if (typeof opts !== 'object') {
		console.warn('Deprecated: Expected third argument to be a object')
		opts = { autoBom: !opts }
	}

	// prepend BOM for UTF-8 XML and text/* types (including HTML)
	// note: your browser will automatically convert UTF-16 U+FEFF to EF BB BF
	if (opts.autoBom && /^\s*(?:text\/\S*|application\/xml|\S*\/\S*\+xml)\s*;.*charset\s*=\s*utf-8/i.test(blob.type)) {
		return new Blob([String.fromCharCode(0xFEFF), blob], { type: blob.type })
	}
	return blob
}

function download(url, name, opts) {
	var xhr = new XMLHttpRequest()
	xhr.open('GET', url)
	xhr.responseType = 'blob'
	xhr.onload = function () {
		saveAs(xhr.response, name, opts)
	}
	xhr.onerror = function () {
		console.error('could not download file')
	}
	xhr.send()
}

function corsEnabled(url) {
	var xhr = new XMLHttpRequest()
	// use sync to avoid popup blocker
	xhr.open('HEAD', url, false)
	try {
		xhr.send()
	} catch (e) { }
	return xhr.status >= 200 && xhr.status <= 299
}

// `a.click()` doesn't work for all browsers (#465)
function click(node) {
	try {
		node.dispatchEvent(new MouseEvent('click'))
	} catch (e) {
		var evt = document.createEvent('MouseEvents')
		evt.initMouseEvent('click', true, true, window, 0, 0, 0, 80,
			20, false, false, false, false, 0, null)
		node.dispatchEvent(evt)
	}
}

var saveAs = _global.saveAs || (
	// probably in some web worker
	(typeof window !== 'object' || window !== _global)
		? function saveAs() { /* noop */ }

		// Use download attribute first if possible (#193 Lumia mobile)
		: 'download' in HTMLAnchorElement.prototype
			? function saveAs(blob, name, opts) {
				var URL = _global.URL || _global.webkitURL
				var a = document.createElement('a')
				name = name || blob.name || 'download'

				a.download = name
				a.rel = 'noopener' // tabnabbing

				// TODO: detect chrome extensions & packaged apps
				// a.target = '_blank'

				if (typeof blob === 'string') {
					// Support regular links
					a.href = blob
					if (a.origin !== location.origin) {
						corsEnabled(a.href)
							? download(blob, name, opts)
							: click(a, a.target = '_blank')
					} else {
						click(a)
					}
				} else {
					// Support blobs
					a.href = URL.createObjectURL(blob)
					setTimeout(function () { URL.revokeObjectURL(a.href) }, 4E4) // 40s
					setTimeout(function () { click(a) }, 0)
				}
			}

			// Use msSaveOrOpenBlob as a second approach
			: 'msSaveOrOpenBlob' in navigator
				? function saveAs(blob, name, opts) {
					name = name || blob.name || 'download'

					if (typeof blob === 'string') {
						if (corsEnabled(blob)) {
							download(blob, name, opts)
						} else {
							var a = document.createElement('a')
							a.href = blob
							a.target = '_blank'
							setTimeout(function () { click(a) })
						}
					} else {
						navigator.msSaveOrOpenBlob(bom(blob, opts), name)
					}
				}

				// Fallback to using FileReader and a popup
				: function saveAs(blob, name, opts, popup) {
					// Open a popup immediately do go around popup blocker
					// Mostly only available on user interaction and the fileReader is async so...
					popup = popup || open('', '_blank')
					if (popup) {
						popup.document.title =
							popup.document.body.innerText = 'downloading...'
					}

					if (typeof blob === 'string') return download(blob, name, opts)

					var force = blob.type === 'application/octet-stream'
					var isSafari = /constructor/i.test(_global.HTMLElement) || _global.safari
					var isChromeIOS = /CriOS\/[\d]+/.test(navigator.userAgent)

					if ((isChromeIOS || (force && isSafari)) && typeof FileReader === 'object') {
						// Safari doesn't allow downloading of blob URLs
						var reader = new FileReader()
						reader.onloadend = function () {
							var url = reader.result
							url = isChromeIOS ? url : url.replace(/^data:[^;]*;/, 'data:attachment/file;')
							if (popup) popup.location.href = url
							else location = url
							popup = null // reverse-tabnabbing #460
						}
						reader.readAsDataURL(blob)
					} else {
						var URL = _global.URL || _global.webkitURL
						var url = URL.createObjectURL(blob)
						if (popup) popup.location = url
						else location.href = url
						popup = null // reverse-tabnabbing #460
						setTimeout(function () { URL.revokeObjectURL(url) }, 4E4) // 40s
					}
				}
)

_global.saveAs = saveAs.saveAs = saveAs

if (typeof module !== 'undefined') {
	module.exports = saveAs;
}