Create TagEditor component (#1558)

Add new preact tag editor component

src/sidebar/components/tag-editor.js

 'use strict';
 
-// @ngInject
-function TagEditorController(tags) {
-  this.onTagsChanged = function() {
-    tags.store(this.tagList);
-
-    const newTags = this.tagList.map(function(item) {
-      return item.text;
-    });
-    this.onEditTags({ tags: newTags });
+const { createElement } = require('preact');
+const propTypes = require('prop-types');
+const { useMemo, useRef, useState } = require('preact/hooks');
+
+const { withServices } = require('../util/service-context');
+const SvgIcon = require('./svg-icon');
+
+// Global counter used to create a unique id for each instance of a TagEditor
+let datalistIdCounter = 0;
+
+/**
+ * Component to edit annotation's tags.
+ */
+
+function TagEditor({ onEditTags, tags: tagsService, tagList }) {
+  const inputEl = useRef(null);
+  const [showSuggestions, setShowSuggestions] = useState(false);
+  const [datalistId] = useState(() => {
+    ++datalistIdCounter;
+    return `tag-editor-datalist-${datalistIdCounter}`;
+  });
+
+  // List of suggestions returned from the tagsService
+  const suggestions = useMemo(() => {
+    // Remove any repeated suggestions that are already tags.
+    const removeDuplicates = (suggestions, tags) => {
+      const suggestionsSet = [];
+      suggestions.forEach(suggestion => {
+        if (tags.indexOf(suggestion) < 0) {
+          suggestionsSet.push(suggestion);
+        }
+      });
+      return suggestionsSet.sort();
+    };
+    // Call filter with an empty string to return all suggestions
+    return removeDuplicates(tagsService.filter(''), tagList);
+  }, [tagsService, tagList]);
+
+  /**
+   * Handle changes to this annotation's tags
+   */
+  const updateTags = tagList => {
+    // update suggested tags list via service
+    tagsService.store(tagList.map(tag => ({ text: tag })));
+    onEditTags({ tags: tagList });
   };
 
-  this.autocomplete = function(query) {
-    return Promise.resolve(tags.filter(query));
+  /**
+   * Remove a tag from this annotation.
+   *
+   * @param {string} tag
+   */
+  const removeTag = tag => {
+    const newTagList = [...tagList]; // make a copy
+    const index = newTagList.indexOf(tag);
+    newTagList.splice(index, 1);
+    updateTags(newTagList);
   };
 
-  this.$onChanges = function(changes) {
-    if (changes.tags) {
-      this.tagList = changes.tags.currentValue.map(function(tag) {
-        return { text: tag };
-      });
+  /**
+   * Adds a tag to the annotation equal to the value of the input field
+   * and then clears out the suggestions list and the input field.
+   */
+  const addTag = () => {
+    const value = inputEl.current.value.trim();
+    if (value.length === 0) {
+      // don't add an empty tag
+      return;
+    }
+    if (tagList.indexOf(value) >= 0) {
+      // don't add duplicate tag
+      return;
+    }
+    updateTags([...tagList, value]);
+    setShowSuggestions(false);
+
+    inputEl.current.value = '';
+    inputEl.current.focus();
+  };
+
+  /**
+   *  If the user pressed enter or comma while focused on
+   *  the <input>, then add a new tag.
+   */
+  const handleKeyPress = e => {
+    if (e.key === 'Enter' || e.key === ',') {
+      addTag();
+      // preventDefault stops the delimiter from being
+      // added to the input field
+      e.preventDefault();
+    }
+  };
+
+  const handleOnInput = e => {
+    if (e.inputType === 'insertText') {
+      // Show the suggestions if the user types something into the field
+      setShowSuggestions(true);
+    } else if (
+      e.inputType === undefined ||
+      e.inputType === 'insertReplacementText'
+    ) {
+      // nb. Chrome / Safari reports undefined and Firefox reports 'insertReplacementText'
+      // for the inputTyp value when clicking on an element in the datalist.
+      //
+      // There are two ways to arrive here, either click an item with the mouse
+      // or use keyboard navigation and press 'Enter'.
+      //
+      // If the input value typed already exactly matches the option selected
+      // then this event won't fire and a user would have to press 'Enter' a second
+      // time to trigger the handleKeyPress callback above to add the tag.
+      // Bug: https://github.com/hypothesis/client/issues/1604
+      addTag();
+    } else if (inputEl.current.value.length === 0) {
+      // If the user deleted input, hide suggestions. This has
+      // no effect in Safari and the list will stay open.
+      setShowSuggestions(false);
     }
   };
+
+  const handleKeyUp = e => {
+    // Safari on macOS and iOS have an issue where pressing "Enter" in an
+    // input when its value exactly matches a suggestion in the associated <datalist>
+    // does not generate a "keypress" event. Therefore we catch the subsequent
+    // "keyup" event instead.
+
+    if (e.key === 'Enter') {
+      // nb. `addTag` will do nothing if the "keypress" event was already handled.
+      addTag();
+    }
+  };
+
+  const suggestionsList = () => {
+    return (
+      <datalist
+        id={datalistId}
+        className="tag-editor__suggestions"
+        aria-label="Annotation suggestions"
+      >
+        {showSuggestions &&
+          suggestions.map(suggestion => (
+            <option key={suggestion} value={suggestion} />
+          ))}
+      </datalist>
+    );
+  };
+
+  return (
+    <section className="tag-editor">
+      <ul
+        className="tag-editor__tag-list"
+        aria-label="Suggested tags for annotation"
+      >
+        {tagList.map(tag => {
+          return (
+            <li
+              key={`${tag}`}
+              className="tag-editor__tag-item"
+              aria-label={`Tag: ${tag}`}
+            >
+              <span className="tag-editor__edit">{tag}</span>
+              <button
+                onClick={() => {
+                  removeTag(tag);
+                }}
+                title={`Remove Tag: ${tag}`}
+                className="tag-editor__delete"
+              >
+                <SvgIcon name="cancel" />
+              </button>
+            </li>
+          );
+        })}
+      </ul>
+      <input
+        list={datalistId}
+        onInput={handleOnInput}
+        onKeyPress={handleKeyPress}
+        onKeyUp={handleKeyUp}
+        ref={inputEl}
+        placeholder="Add tags..."
+        className="tag-editor__input"
+        type="text"
+      />
+      {suggestionsList()}
+    </section>
+  );
 }
 
-module.exports = {
-  controller: TagEditorController,
-  controllerAs: 'vm',
-  bindings: {
-    tags: '<',
-    onEditTags: '&',
-  },
-  template: require('../templates/tag-editor.html'),
+/**
+ * @typedef Tag
+ * @param tag {string} - The tag text
+ */
+
+TagEditor.propTypes = {
+  /**
+   *  Callback that saves the tag list.
+   *
+   *  @param {Array<Tag>} - Array of tags to save
+   */
+  onEditTags: propTypes.func.isRequired,
+
+  /* The list of editable tags as strings. */
+  tagList: propTypes.array.isRequired,
+
+  /** Services */
+  tags: propTypes.object.isRequired,
+  serviceUrl: propTypes.func.isRequired,
 };
+
+TagEditor.injectedProps = ['serviceUrl', 'tags'];
+
+module.exports = withServices(TagEditor);

src/sidebar/components/tag-list.js

@@ -60,10 +60,10 @@ function TagList({ annotation, serviceUrl, settings, tags }) {
 
 TagList.propTypes = {
   /* Annotation that owns the tags. */
-  annotation: propTypes.object,
+  annotation: propTypes.object.isRequired,
 
   /* List of tags as strings. */
-  tags: propTypes.array,
+  tags: propTypes.array.isRequired,
 
   /** Services */
   serviceUrl: propTypes.func,

src/sidebar/index.js

@@ -194,7 +194,10 @@ function startAngularApp(config) {
     )
     .component('streamContent', require('./components/stream-content'))
     .component('svgIcon', wrapReactComponent(require('./components/svg-icon')))
-    .component('tagEditor', require('./components/tag-editor'))
+    .component(
+      'tagEditor',
+      wrapReactComponent(require('./components/tag-editor'))
+    )
     .component('tagList', wrapReactComponent(require('./components/tag-list')))
     .component('threadList', require('./components/thread-list'))
     .component('topBar', wrapReactComponent(require('./components/top-bar')))

src/sidebar/templates/annotation.html

@@ -37,12 +37,16 @@
       h-branding="accentColor">mire</a>
   </div>
   <!-- Tags -->
-  <div class="annotation-body" ng-if="vm.editing()">
-    <tag-editor tags="vm.state().tags"
-                on-edit-tags="vm.setTags(tags)"></tag-editor>
-  </div>
+  <tag-editor
+    ng-if="vm.editing()"
+    annotation="vm.annotation"
+    on-edit-tags="vm.setTags(tags)"
+    tag-list="vm.state().tags" 
+    />
+  </tag-editor>
 
   <tag-list
+    ng-if="!vm.editing()"
     annotation="vm.annotation"
     tags="vm.state().tags"
   ></tag-list>

src/sidebar/templates/tag-editor.html

-<tags-input ng-model="vm.tagList"
-  name="tags"
-  class="tags"
-  placeholder="Add tags…"
-  min-length="1"
-  replace-spaces-with-dashes="false"
-  enable-editing-last-tag="true"
-  on-tag-added="vm.onTagsChanged()"
-  on-tag-removed="vm.onTagsChanged()">
-  <auto-complete source="vm.autocomplete($query)"
-    min-length="1"
-    max-results-to-show="10"></auto-complete>
-</tags-input>

src/styles/sidebar/components/tag-editor.scss

+@use "../../mixins/forms";
+@use "../../mixins/buttons";
+@use "../../variables" as var;
+
+.tag-editor {
+  &__input {
+    @include forms.form-input;
+    width: 100%;
+    &:focus {
+      @include forms.form-input-focus;
+    }
+  }
+
+  &__tag-list {
+    display: flex;
+    flex-wrap: wrap;
+  }
+
+  &__tag-item {
+    display: flex;
+    margin-right: 0.5em;
+    margin-bottom: 0.5em;
+  }
+
+  &__edit {
+    color: var.$grey-6;
+    background: var.$grey-1;
+    border: 1px solid var.$grey-3;
+    border-radius: 2px 0 0 2px;
+    border-right-width: 0;
+    padding: 0 0.5em;
+  }
+
+  &__delete {
+    @include buttons.button-base;
+    background-color: var.$grey-1;
+    padding: 0 0.5em;
+    border: 1px solid var.$grey-3;
+    border-radius: 0 2px 2px 0;
+
+    &:hover {
+      background-color: var.$grey-2;
+    }
+  }
+}

src/styles/sidebar/sidebar.scss

@@ -60,6 +60,7 @@
 @use './components/sidebar-panel';
 @use './components/svg-icon';
 @use './components/spinner';
+@use './components/tag-editor';
 @use './components/tag-list';
 @use './components/tags-input';
 @use './components/thread-list';