jQuery html5 drag drop file upload progress preview mime list json response event csrf-token

gistfile1.txt

(function ($) {
//based on that nice demo at https://html5demos.com/dnd-upload/
    $.fn.upl = function (options) {

        var tests = {
                filereader: typeof FileReader != 'undefined',
                dnd: 'draggable' in document.createElement('span'),
                formdata: !!window.FormData,
                progress: "upload" in new XMLHttpRequest
            },
            acceptedTypes = {
                'image/png': true,
                'image/jpeg': true,
                'image/gif': true
            },
            settings = $.extend({
                route: '/set_the_path_to_server_here.php',
                progress: '.progress',
                preview: '.preview',
                name: 'files'
            }, options);

        var previewfile = function (file, el) {
            var preview = $(el).find(settings.preview)[0];
            if (!acceptedTypes[file.type] === true) {
                preview.innerHTML += file.name + ' not supported type: ' + file.type + '\n';
                return false;
            }
            if (tests.filereader === true) {
                var reader = new FileReader();
                reader.onload = function (event) {
                    var image = new Image();
                    image.src = event.target.result;
                    preview.appendChild(image);
                };
                reader.readAsDataURL(file);
            } else {
                preview.innerHTML += '<p>Uploaded ' + file.name + ' ' + (file.size ? (file.size / 1024 | 0) + 'K' : '');
            }
        };
        var readfiles = function (files, el) {
            var progress = $(el).find(settings.progress)[0];
            var formData = tests.formdata ? new FormData() : null;
            var csrf = document.head.querySelector('meta[name="csrf-token"]').content;
            if (tests.formdata) {
                for (var i = 0; i < files.length; i++) {
                    formData.append(settings.name + '[' + i + ']', files[i]);
                    previewfile(files[i], el);
                }
                var xhr = new XMLHttpRequest();
                xhr.onreadystatechange = function() {
                    if (xhr.readyState == XMLHttpRequest.DONE) {
                        $(el).trigger("completed",xhr.responseText);

                    }
                }
                xhr.open('POST', settings.route);
                if (csrf != undefined) {
                    xhr.setRequestHeader('X-CSRF-TOKEN', csrf);
                }
                if (tests.progress) {
                    xhr.upload.onprogress = function (event) {
                        if (event.lengthComputable) {
                            var complete = (event.loaded / event.total * 100 | 0);
                            progress.value = progress.innerHTML = complete;
                        }
                    }
                    xhr.onload = function () {
                        progress.value = progress.innerHTML = 100;

                        setTimeout(function(){
                            progress.value = progress.innerHTML = 0;
                        },2000);
                    };
                }
                xhr.send(formData);
            } else {
                $(el).find(settings.preview)[0].innerHTML = 'File upload not supported.';
            }
        }
        this.each(function (i, el) {
            var inp = $('<input type="file"  style="display: none"  name="' + settings.name + '[]">').on('change', function (e) {
                readfiles(e.target.files, el);
            });
            var preview = $(el).find(settings.preview)[0];
            inp.insertAfter(preview);
            $(preview).on('click', function () {
                inp.trigger('click');
            })
            if (tests.dnd) {
                el.ondragover = function (e) {
                    //  el.className = 'hover';
                    e.stopPropagation();
                    return false;
                };
                el.ondragend = function (e) {
                    //el.className = '';
                    e.stopPropagation();
                    return false;
                };
                el.ondrop = function (e) {
                    // el.className = '';
                    e.preventDefault();
                    e.stopPropagation();
                    if (e.dataTransfer.files && e.dataTransfer.files.length > 0) {
                        readfiles(e.dataTransfer.files, el);
                    }

                }
            }
        }); //each
    };
}(jQuery));