Generalize protected branch/tag dropdowns

Remove duplicate ee code

This was generalized for usage in the new variable table design, see
https://gitlab.com/gitlab-org/gitlab-ce/issues/39118#note_53615249

Conflicts:
	app/assets/stylesheets/pages/projects.scss
	ee/app/assets/javascripts/protected_branches/protected_branch_create.js
	ee/app/assets/javascripts/protected_tags/protected_tag_create.js
	ee/app/views/projects/protected_branches/ee/_dropdown.html.haml

1 files changed, 91 insertions, 0 deletions

diff --git a/app/assets/javascripts/create_item_dropdown.js b/app/assets/javascripts/create_item_dropdown.js
new file mode 100644
index 00000000000..c3eceb285f5
--- /dev/null
+++ b/app/assets/javascripts/create_item_dropdown.js
@@ -0,0 +1,91 @@
+import _ from 'underscore';
+
+export default class CreateItemDropdown {
+  /**
+   * @param {Object} options containing
+   *                         `$dropdown` target element
+   *                          `onSelect` event callback
+   * $dropdown must be an element created using `dropdown_tag()` rails helper
+   */
+  constructor(options) {
+    this.defaultToggleLabel = options.defaultToggleLabel;
+    this.fieldName = options.fieldName;
+    this.onSelect = options.onSelect || (() => {});
+    this.getDataOption = options.getData;
+    this.$dropdown = options.$dropdown;
+    this.$dropdownContainer = this.$dropdown.parent();
+    this.$dropdownFooter = this.$dropdownContainer.find('.dropdown-footer');
+    this.$createButton = this.$dropdownContainer.find('.js-dropdown-create-new-item');
+
+    this.buildDropdown();
+    this.bindEvents();
+
+    // Hide footer
+    this.toggleFooter(true);
+  }
+
+  buildDropdown() {
+    this.$dropdown.glDropdown({
+      data: this.getData.bind(this),
+      filterable: true,
+      remote: false,
+      search: {
+        fields: ['title'],
+      },
+      selectable: true,
+      toggleLabel(selected) {
+        return (selected && 'id' in selected) ? selected.title : this.defaultToggleLabel;
+      },
+      fieldName: this.fieldName,
+      text(item) {
+        return _.escape(item.title);
+      },
+      id(item) {
+        return _.escape(item.id);
+      },
+      onFilter: this.toggleCreateNewButton.bind(this),
+      clicked: (options) => {
+        options.e.preventDefault();
+        this.onSelect();
+      },
+    });
+  }
+
+  bindEvents() {
+    this.$createButton.on('click', this.onClickCreateWildcard.bind(this));
+  }
+
+  onClickCreateWildcard(e) {
+    e.preventDefault();
+
+    // Refresh the dropdown's data, which ends up calling `getData`
+    this.$dropdown.data('glDropdown').remote.execute();
+    this.$dropdown.data('glDropdown').selectRowAtIndex();
+  }
+
+  getData(term, callback) {
+    this.getDataOption(term, (data = []) => {
+      callback(data.concat(this.selectedItem || []));
+    });
+  }
+
+  toggleCreateNewButton(item) {
+    if (item) {
+      this.selectedItem = {
+        title: item,
+        id: item,
+        text: item,
+      };
+
+      this.$dropdownContainer
+        .find('.js-dropdown-create-new-item code')
+        .text(item);
+    }
+
+    this.toggleFooter(!item);
+  }
+
+  toggleFooter(toggleState) {
+    this.$dropdownFooter.toggleClass('hidden', toggleState);
+  }
+}