/*! FileSaver.js

 *  A saveAs() FileSaver implementation.

 *  2014-01-24

 *

 *  By Eli Grey, http://eligrey.com

 *  License: X11/MIT

 *    See LICENSE.md

 */

/*global self */

/*jslint bitwise: true, indent: 4, laxbreak: true, laxcomma: true, smarttabs: true, plusplus: true */

/*! @source http://purl.eligrey.com/github/FileSaver.js/blob/master/FileSaver.js */

var saveAs = saveAs

  // IE 10+ (native saveAs)

  || (typeof navigator !== "undefined" &&

      navigator.msSaveOrOpenBlob && navigator.msSaveOrOpenBlob.bind(navigator))

  // Everyone else

  || (function(view) {

	"use strict";

	// IE <10 is explicitly unsupported

	if (typeof navigator !== "undefined" &&

	    /MSIE [1-9]\./.test(navigator.userAgent)) {

		return;

	}

	var

		  doc = view.document

		  // only get URL when necessary in case BlobBuilder.js hasn't overridden it yet

		, get_URL = function() {

			return view.URL || view.webkitURL || view;

		}

		, URL = view.URL || view.webkitURL || view

		, save_link = doc.createElementNS("http://www.w3.org/1999/xhtml", "a")

		, can_use_save_link = !view.externalHost && "download" in save_link

		, click = function(node) {

			var event = doc.createEvent("MouseEvents");

			event.initMouseEvent(

				"click", true, false, view, 0, 0, 0, 0, 0

				, false, false, false, false, 0, null

			);

			node.dispatchEvent(event);

		}

		, webkit_req_fs = view.webkitRequestFileSystem

		, req_fs = view.requestFileSystem || webkit_req_fs || view.mozRequestFileSystem

		, throw_outside = function(ex) {

			(view.setImmediate || view.setTimeout)(function() {

				throw ex;

			}, 0);

		}

		, force_saveable_type = "application/octet-stream"

		, fs_min_size = 0

		, deletion_queue = []

		, process_deletion_queue = function() {

			var i = deletion_queue.length;

			while (i--) {

				var file = deletion_queue[i];

				if (typeof file === "string") { // file is an object URL

					URL.revokeObjectURL(file);

				} else { // file is a File

					file.remove();

				}

			}

			deletion_queue.length = 0; // clear queue

		}

		, dispatch = function(filesaver, event_types, event) {

			event_types = [].concat(event_types);

			var i = event_types.length;

			while (i--) {

				var listener = filesaver["on" + event_types[i]];

				if (typeof listener === "function") {

					try {

						listener.call(filesaver, event || filesaver);

					} catch (ex) {

						throw_outside(ex);

					}

				}

			}

		}

		, FileSaver = function(blob, name) {

			// First try a.download, then web filesystem, then object URLs

			var

				  filesaver = this

				, type = blob.type

				, blob_changed = false

				, object_url

				, target_view

				, get_object_url = function() {

					var object_url = get_URL().createObjectURL(blob);

					deletion_queue.push(object_url);

					return object_url;

				}

				, dispatch_all = function() {

					dispatch(filesaver, "writestart progress write writeend".split(" "));

				}

				// on any filesys errors revert to saving with object URLs

				, fs_error = function() {

					// don't create more object URLs than needed

					if (blob_changed || !object_url) {

						object_url = get_object_url(blob);

					}

					if (target_view) {

						target_view.location.href = object_url;

					} else {

						window.open(object_url, "_blank");

					}

					filesaver.readyState = filesaver.DONE;

					dispatch_all();

				}

				, abortable = function(func) {

					return function() {

						if (filesaver.readyState !== filesaver.DONE) {

							return func.apply(this, arguments);

						}

					};

				}

				, create_if_not_found = {create: true, exclusive: false}

				, slice

			;

			filesaver.readyState = filesaver.INIT;

			if (!name) {

				name = "download";

			}

			if (can_use_save_link) {

				object_url = get_object_url(blob);

				// FF for Android has a nasty garbage collection mechanism

				// that turns all objects that are not pure javascript into 'deadObject'

				// this means `doc` and `save_link` are unusable and need to be recreated

				// `view` is usable though:

				doc = view.document;

				save_link = doc.createElementNS("http://www.w3.org/1999/xhtml", "a");

				save_link.href = object_url;

				save_link.download = name;

				var event = doc.createEvent("MouseEvents");

				event.initMouseEvent(

					"click", true, false, view, 0, 0, 0, 0, 0

					, false, false, false, false, 0, null

				);

				save_link.dispatchEvent(event);

				filesaver.readyState = filesaver.DONE;

				dispatch_all();

				return;

			}

			// Object and web filesystem URLs have a problem saving in Google Chrome when

			// viewed in a tab, so I force save with application/octet-stream

			// http://code.google.com/p/chromium/issues/detail?id=91158

			if (view.chrome && type && type !== force_saveable_type) {

				slice = blob.slice || blob.webkitSlice;

				blob = slice.call(blob, 0, blob.size, force_saveable_type);

				blob_changed = true;

			}

			// Since I can't be sure that the guessed media type will trigger a download

			// in WebKit, I append .download to the filename.

			// https://bugs.webkit.org/show_bug.cgi?id=65440

			if (webkit_req_fs && name !== "download") {

				name += ".download";

			}

			if (type === force_saveable_type || webkit_req_fs) {

				target_view = view;

			}

			if (!req_fs) {

				fs_error();

				return;

			}

			fs_min_size += blob.size;

			req_fs(view.TEMPORARY, fs_min_size, abortable(function(fs) {

				fs.root.getDirectory("saved", create_if_not_found, abortable(function(dir) {

					var save = function() {

						dir.getFile(name, create_if_not_found, abortable(function(file) {

							file.createWriter(abortable(function(writer) {

								writer.onwriteend = function(event) {

									target_view.location.href = file.toURL();

									deletion_queue.push(file);

									filesaver.readyState = filesaver.DONE;

									dispatch(filesaver, "writeend", event);

								};

								writer.onerror = function() {

									var error = writer.error;

									if (error.code !== error.ABORT_ERR) {

										fs_error();

									}

								};

								"writestart progress write abort".split(" ").forEach(function(event) {

									writer["on" + event] = filesaver["on" + event];

								});

								writer.write(blob);

								filesaver.abort = function() {

									writer.abort();

									filesaver.readyState = filesaver.DONE;

								};

								filesaver.readyState = filesaver.WRITING;

							}), fs_error);

						}), fs_error);

					};

					dir.getFile(name, {create: false}, abortable(function(file) {

						// delete file if it already exists

						file.remove();

						save();

					}), abortable(function(ex) {

						if (ex.code === ex.NOT_FOUND_ERR) {

							save();

						} else {

							fs_error();

						}

					}));

				}), fs_error);

			}), fs_error);

		}

		, FS_proto = FileSaver.prototype

		, saveAs = function(blob, name) {

			return new FileSaver(blob, name);

		}

	;

	FS_proto.abort = function() {

		var filesaver = this;

		filesaver.readyState = filesaver.DONE;

		dispatch(filesaver, "abort");

	};

	FS_proto.readyState = FS_proto.INIT = 0;

	FS_proto.WRITING = 1;

	FS_proto.DONE = 2;

	FS_proto.error =

	FS_proto.onwritestart =

	FS_proto.onprogress =

	FS_proto.onwrite =

	FS_proto.onabort =

	FS_proto.onerror =

	FS_proto.onwriteend =

		null;

	view.addEventListener("unload", process_deletion_queue, false);

	saveAs.unload = function() {

		process_deletion_queue();

		view.removeEventListener("unload", process_deletion_queue, false);

	};

	return saveAs;

}(

	   typeof self !== "undefined" && self

	|| typeof window !== "undefined" && window

	|| this.content

));

// `self` is undefined in Firefox for Android content script context

// while `this` is nsIContentFrameMessageManager

// with an attribute `content` that corresponds to the window

if (typeof module !== "undefined" && module !== null) {

  module.exports = saveAs;

} else if ((typeof define !== "undefined" && define !== null) && (define.amd != null)) {

  define([], function() {

    return saveAs;

  });

}