export default Em.Mixin.create({
  uploading: false,
  uploadProgress: 0,

  uploadDone() {
    Em.warn("You should implement `uploadDone`");
  },

  _initialize: function() {
    const $upload = this.$(),
          csrf = Discourse.Session.currentProp("csrfToken"),
          uploadUrl = Discourse.getURL(this.getWithDefault("uploadUrl", "/uploads")),
          reset = () => this.setProperties({ uploading: false, uploadProgress: 0});

    this.messageBus.subscribe("/uploads/" + this.get("type"), upload => {
      if (upload && upload.url) {
        this.uploadDone(upload);
      } else {
        Discourse.Utilities.displayErrorForUpload(upload);
      }
      reset();
    });

    $upload.fileupload({
      url: uploadUrl + ".json?client_id=" + this.messageBus.clientId + "&authenticity_token=" + encodeURIComponent(csrf),
      dataType: "json",
      dropZone: $upload,
      pasteZone: $upload
    });

    $upload.on("fileuploaddrop", (e, data) => {
      if (data.files.length > 10) {
        bootbox.alert(I18n.t("post.errors.too_many_dragged_and_dropped_files"));
        return false;
      } else {
        return true;
      }
    });

    $upload.on("fileuploadsubmit", (e, data) => {
      const isValid = Discourse.Utilities.validateUploadedFiles(data.files, true);
      let form = { type: this.get("type") };
      if (this.get("data")) { form = $.extend(form, this.get("data")); }
      data.formData = form;
      this.setProperties({ uploadProgress: 0, uploading: isValid });
      return isValid;
    });

    $upload.on("fileuploadprogressall", (e, data) => {
      const progress = parseInt(data.loaded / data.total * 100, 10);
      this.set("uploadProgress", progress);
    });

    $upload.on("fileuploadfail", (e, data) => {
      Discourse.Utilities.displayErrorForUpload(data);
      reset();
    });
  }.on("didInsertElement"),

  _destroy: function() {
    this.messageBus.unsubscribe("/uploads/" + this.get("type"));
    const $upload = this.$();
    try { $upload.fileupload("destroy"); }
    catch (e) { /* wasn't initialized yet */ }
    $upload.off();
  }.on("willDestroyElement")
});