TinyMce with file upload

tinymce.js

$(function () {
    var editorCount = 0;

    $('.richtext').each(function () {

        var sendFile = function (callback) {
            data = new FormData();
            data.append("file", fileInput[0].files[0]);
            $.ajax({
                url: "/upload/image",
                data: data,
                cache: false,
                contentType: false,
                processData: false,
                type: 'POST',
                success: function (data) {
                    callback(data.filename);
                },
                error: function (jqXHR, textStatus, errorThrown) {
                    try {
                    var message = JSON.parse(jqXHR.responseText).file[0];
                    message = message.replace(/^[a-z]/, function (letter) {
                        return letter.toUpperCase();
                    });
                    alert(message);
                    } catch (e) {
                        alert('Whoops');
                    }
                }
            });
        };

        editorCount++;

        var textarea = $(this);
        var editorId = editorCount;
        var uploadCallback;

        textarea.attr('data-editor-id', editorId);

        var form = $(
            '<form method="post" enctype="multipart/form-data" style="width:0;height:0;overflow:hidden">' +
            '<input name="file" type="file">' +
            '</form>'
        );
        $('body').append(form);
        var fileInput = form.find('input').first();

        fileInput.change(function () {
            sendFile(uploadCallback);
        });

        tinymce.init({
            selector: '[data-editor-id=' + editorId + ']',
            height: 500,
            theme: 'modern',
            plugins: [
                'autolink lists link image hr anchor',
                'wordcount visualblocks code fullscreen',
                'insertdatetime media nonbreaking table contextmenu',
                'paste textcolor colorpicker textpattern'
            ],
            toolbar1: 'insertfile undo redo | styleselect | bold italic | alignleft aligncenter alignright alignjustify | bullist numlist outdent indent | link image',
            toolbar2: 'print preview media | forecolor backcolor emoticons',
            image_advtab: true,
            content_css: [
                $('.main-css').attr('href')
            ],
            file_browser_callback_types: 'image',
            file_picker_callback: function (callback, value, meta) {

                // Provide image and alt text for the image dialog
                if (meta.filetype == 'image') {
                    fileInput.click();
                    uploadCallback = callback;
                }

                /* --- left as an example --
                 // Provide file and text for the link dialog
                 if (meta.filetype == 'file') {
                 callback('mypage.html', {text: 'My text'});
                 }
                 // Provide alternative source and posted for the media dialog
                 if (meta.filetype == 'media') {
                 callback('movie.mp4', {source2: 'alt.ogg', poster: 'image.jpg'});
                 }
                 */
            },
            relative_urls: false,
            remove_script_host: true
        });

    });
});