/*
 * jQuery File Download Plugin v1.4.3
 *
 * http://www.johnculviner.com
 *
 * Copyright (c) 2013 - John Culviner
 *
 * Licensed under the MIT license:
 *   http://www.opensource.org/licenses/mit-license.php
 *
 * !!!!NOTE!!!!
 * You must also write a cookie in conjunction with using this plugin as mentioned in the orignal post:
 * http://johnculviner.com/jquery-file-download-plugin-for-ajax-like-feature-rich-file-downloads/
 * !!!!NOTE!!!!
 */

(function($, window){
    // i'll just put them here to get evaluated on script load
    var htmlSpecialCharsRegEx = /[<>&\r\n"']/gm;
    var htmlSpecialCharsPlaceHolders = {
        '<': 'lt;',
        '>': 'gt;',
        '&': 'amp;',
        '\r': "#13;",
        '\n': "#10;",
        '"': 'quot;',
        "'": '#39;' /*single quotes just to be safe, IE8 doesn't support &apos;, so use &#39; instead */
    };

    $.extend({
        //
        //$.fileDownload('/path/to/url/', options)
        //  see directly below for possible 'options'
        fileDownload: function (fileUrl, options) {

            //provide some reasonable defaults to any unspecified options below
            var settings = $.extend({

                //
                //Requires jQuery UI: provide a message to display to the user when the file download is being prepared before the browser's dialog appears
                //
                preparingMessageHtml: null,

                //
                //Requires jQuery UI: provide a message to display to the user when a file download fails
                //
                failMessageHtml: null,

                //
                //the stock android browser straight up doesn't support file downloads initiated by a non GET: http://code.google.com/p/android/issues/detail?id=1780
                //specify a message here to display if a user tries with an android browser
                //if jQuery UI is installed this will be a dialog, otherwise it will be an alert
                //Set to null to disable the message and attempt to download anyway
                //
                androidPostUnsupportedMessageHtml: "Unfortunately your Android browser doesn't support this type of file download. Please try again with a different browser.",

                //
                //Requires jQuery UI: options to pass into jQuery UI Dialog
                //
                dialogOptions: { modal: true },

                //
                //a function to call while the dowload is being prepared before the browser's dialog appears
                //Args:
                //  url - the original url attempted
                //
                prepareCallback: function (url) { },

                //
                //a function to call after a file download dialog/ribbon has appeared
                //Args:
                //  url - the original url attempted
                //
                successCallback: function (url) { },

                //
                //a function to call after a file download dialog/ribbon has appeared
                //Args:
                //  responseHtml    - the html that came back in response to the file download. this won't necessarily come back depending on the browser.
                //                      in less than IE9 a cross domain error occurs because 500+ errors cause a cross domain issue due to IE subbing out the
                //                      server's error message with a "helpful" IE built in message
                //  url             - the original url attempted
                //
                failCallback: function (responseHtml, url) { },

                //
                // the HTTP method to use. Defaults to "GET".
                //
                httpMethod: "GET",

                //
                // if specified will perform a "httpMethod" request to the specified 'fileUrl' using the specified data.
                // data must be an object (which will be $.param serialized) or already a key=value param string
                //
                data: null,

                //
                //a period in milliseconds to poll to determine if a successful file download has occured or not
                //
                checkInterval: 100,

                //
                //the cookie name to indicate if a file download has occured
                //
                cookieName: "fileDownload",

                //
                //the cookie value for the above name to indicate that a file download has occured
                //
                cookieValue: "true",

                //
                //the cookie path for above name value pair
                //
                cookiePath: "/",

                //
                //if specified it will be used when attempting to clear the above name value pair
                //useful for when downloads are being served on a subdomain (e.g. downloads.example.com)
                //
                cookieDomain: null,

                //
                //the title for the popup second window as a download is processing in the case of a mobile browser
                //
                popupWindowTitle: "Initiating file download...",

                //
                //Functionality to encode HTML entities for a POST, need this if data is an object with properties whose values contains strings with quotation marks.
                //HTML entity encoding is done by replacing all &,<,>,',",\r,\n characters.
                //Note that some browsers will POST the string htmlentity-encoded whilst others will decode it before POSTing.
                //It is recommended that on the server, htmlentity decoding is done irrespective.
                //
                encodeHTMLEntities: true

            }, options);

            var deferred = new $.Deferred();

            //Setup mobile browser detection: Partial credit: http://detectmobilebrowser.com/
            var userAgent = (navigator.userAgent || navigator.vendor || window.opera).toLowerCase();

            var isIos;                  //has full support of features in iOS 4.0+, uses a new window to accomplish this.
            var isAndroid;              //has full support of GET features in 4.0+ by using a new window. Non-GET is completely unsupported by the browser. See above for specifying a message.
            var isOtherMobileBrowser;   //there is no way to reliably guess here so all other mobile devices will GET and POST to the current window.

            if (/ip(ad|hone|od)/.test(userAgent)) {

                isIos = true;

            } else if (userAgent.indexOf('android') !== -1) {

                isAndroid = true;

            } else {

                isOtherMobileBrowser = /avantgo|bada\/|blackberry|blazer|compal|elaine|fennec|hiptop|playbook|silk|iemobile|iris|kindle|lge |maemo|midp|mmp|netfront|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|symbian|treo|up\.(browser|link)|vodafone|wap|windows (ce|phone)|xda|xiino/i.test(userAgent) || /1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|e\-|e\/|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(di|rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|xda(\-|2|g)|yas\-|your|zeto|zte\-/i.test(userAgent.substr(0, 4));

            }

            var httpMethodUpper = settings.httpMethod.toUpperCase();

            if (isAndroid && httpMethodUpper !== "GET" && settings.androidPostUnsupportedMessageHtml) {
                //the stock android browser straight up doesn't support file downloads initiated by non GET requests: http://code.google.com/p/android/issues/detail?id=1780

                if ($().dialog) {
                    $("<div>").html(settings.androidPostUnsupportedMessageHtml).dialog(settings.dialogOptions);
                } else {
                    alert(settings.androidPostUnsupportedMessageHtml);
                }

                return deferred.reject();
            }

            var $preparingDialog = null;

            var internalCallbacks = {

                onPrepare: function (url) {

                    //wire up a jquery dialog to display the preparing message if specified
                    if (settings.preparingMessageHtml) {

                        $preparingDialog = $("<div>").html(settings.preparingMessageHtml).dialog(settings.dialogOptions);

                    } else if (settings.prepareCallback) {

                        settings.prepareCallback(url);

                    }

                },

                onSuccess: function (url) {

                    //remove the perparing message if it was specified
                    if ($preparingDialog) {
                        $preparingDialog.dialog('close');
                    };

                    settings.successCallback(url);

                    deferred.resolve(url);
                },

                onFail: function (responseHtml, url) {

                    //remove the perparing message if it was specified
                    if ($preparingDialog) {
                        $preparingDialog.dialog('close');
                    };

                    //wire up a jquery dialog to display the fail message if specified
                    if (settings.failMessageHtml) {
                        $("<div>").html(settings.failMessageHtml).dialog(settings.dialogOptions);
                    }

                    settings.failCallback(responseHtml, url);

                    deferred.reject(responseHtml, url);
                }
            };

            internalCallbacks.onPrepare(fileUrl);

            //make settings.data a param string if it exists and isn't already
            if (settings.data !== null && typeof settings.data !== "string") {
                settings.data = $.param(settings.data);
            }


            var $iframe,
                downloadWindow,
                formDoc,
                $form;

            if (httpMethodUpper === "GET") {

                if (settings.data !== null) {
                    //need to merge any fileUrl params with the data object

                    var qsStart = fileUrl.indexOf('?');

                    if (qsStart !== -1) {
                        //we have a querystring in the url

                        if (fileUrl.substring(fileUrl.length - 1) !== "&") {
                            fileUrl = fileUrl + "&";
                        }
                    } else {

                        fileUrl = fileUrl + "?";
                    }

                    fileUrl = fileUrl + settings.data;
                }

                if (isIos || isAndroid) {

                    downloadWindow = window.open(fileUrl);
                    downloadWindow.document.title = settings.popupWindowTitle;
                    window.focus();

                } else if (isOtherMobileBrowser) {

                    window.location(fileUrl);

                } else {

                    //create a temporary iframe that is used to request the fileUrl as a GET request
                    $iframe = $("<iframe>")
                        .hide()
                        .prop("src", fileUrl)
                        .appendTo("body");
                }

            } else {

                var formInnerHtml = "";

                if (settings.data !== null) {

                    $.each(settings.data.replace(/\+/g, ' ').split("&"), function () {

                        var kvp = this.split("=");

                        var key = settings.encodeHTMLEntities ? htmlSpecialCharsEntityEncode(decodeURIComponent(kvp[0])) : decodeURIComponent(kvp[0]);
                        if (key) {
                            var value = settings.encodeHTMLEntities ? htmlSpecialCharsEntityEncode(decodeURIComponent(kvp[1])) : decodeURIComponent(kvp[1]);
                            formInnerHtml += '<input type="hidden" name="' + key + '" value="' + value + '" />';
                        }
                    });
                }

                if (isOtherMobileBrowser) {

                    $form = $("<form>").appendTo("body");
                    $form.hide()
                        .prop('method', settings.httpMethod)
                        .prop('action', fileUrl)
                        .html(formInnerHtml);

                } else {

                    if (isIos) {

                        downloadWindow = window.open("about:blank");
                        downloadWindow.document.title = settings.popupWindowTitle;
                        formDoc = downloadWindow.document;
                        window.focus();

                    } else {

                        $iframe = $("<iframe style='display: none' src='about:blank'></iframe>").appendTo("body");
                        formDoc = getiframeDocument($iframe);
                    }

                    formDoc.write("<html><head></head><body><form method='" + settings.httpMethod + "' action='" + fileUrl + "'>" + formInnerHtml + "</form>" + settings.popupWindowTitle + "</body></html>");
                    $form = $(formDoc).find('form');
                }

                $form.submit();
            }


            //check if the file download has completed every checkInterval ms
            setTimeout(checkFileDownloadComplete, settings.checkInterval);


            function checkFileDownloadComplete() {
                //has the cookie been written due to a file download occuring?
                if (document.cookie.indexOf(settings.cookieName + "=" + settings.cookieValue) != -1) {

                    //execute specified callback
                    internalCallbacks.onSuccess(fileUrl);

                    //remove cookie
                    var cookieData = settings.cookieName + "=; path=" + settings.cookiePath + "; expires=" + new Date(0).toUTCString() + ";";
                    if (settings.cookieDomain) cookieData += " domain=" + settings.cookieDomain + ";";
                    document.cookie = cookieData;

                    //remove iframe
                    cleanUp(false);

                    return;
                }

                //has an error occured?
                //if neither containers exist below then the file download is occuring on the current window
                if (downloadWindow || $iframe) {

                    //has an error occured?
                    try {

                        var formDoc = downloadWindow ? downloadWindow.document : getiframeDocument($iframe);

                        if (formDoc && formDoc.body != null && formDoc.body.innerHTML.length) {

                            var isFailure = true;

                            if ($form && $form.length) {
                                var $contents = $(formDoc.body).contents().first();

                                try {
                                    if ($contents.length && $contents[0] === $form[0]) {
                                        isFailure = false;
                                    }
                                } catch (e) {
                                    if (e && e.number == -2146828218) {
                                        // IE 8-10 throw a permission denied after the form reloads on the "$contents[0] === $form[0]" comparison
                                        isFailure = true;
                                    } else {
                                        throw e;
                                    }
                                }
                            }

                            if (isFailure) {
                                // IE 8-10 don't always have the full content available right away, they need a litle bit to finish
                                setTimeout(function () {
                                    internalCallbacks.onFail(formDoc.body.innerHTML, fileUrl);
                                    cleanUp(true);
                                }, 100);

                                return;
                            }
                        }
                    }
                    catch (err) {

                        //500 error less than IE9
                        internalCallbacks.onFail('', fileUrl);

                        cleanUp(true);

                        return;
                    }
                }


                //keep checking...
                setTimeout(checkFileDownloadComplete, settings.checkInterval);
            }

            //gets an iframes document in a cross browser compatible manner
            function getiframeDocument($iframe) {
                var iframeDoc = $iframe[0].contentWindow || $iframe[0].contentDocument;
                if (iframeDoc.document) {
                    iframeDoc = iframeDoc.document;
                }
                return iframeDoc;
            }

            function cleanUp(isFailure) {

                setTimeout(function() {

                    if (downloadWindow) {

                        if (isAndroid) {
                            downloadWindow.close();
                        }

                        if (isIos) {
                            if (downloadWindow.focus) {
                                downloadWindow.focus(); //ios safari bug doesn't allow a window to be closed unless it is focused
                                if (isFailure) {
                                    downloadWindow.close();
                                }
                            }
                        }
                    }

                    //iframe cleanup appears to randomly cause the download to fail
                    //not doing it seems better than failure...
                    //if ($iframe) {
                    //    $iframe.remove();
                    //}

                }, 0);
            }


            function htmlSpecialCharsEntityEncode(str) {
                return str.replace(htmlSpecialCharsRegEx, function(match) {
                    return '&' + htmlSpecialCharsPlaceHolders[match];
                });
            }
            var promise = deferred.promise();
            promise.abort = function() {
                cleanUp();
                $iframe.remove();
            };
            return promise;
        }
    });

})(jQuery, this);