Merge pull request #1890 from matrix-org/matthew/slate

Replace Draft with Slate

.eslintrc.js

@@ -95,6 +95,7 @@ module.exports = {
         "new-cap": ["warn"],
         "key-spacing": ["warn"],
         "prefer-const": ["warn"],
+        "arrow-parens": "off",
 
         // crashes currently: https://github.com/eslint/eslint/issues/6274
         "generator-star-spacing": "off",

docs/slate-formats.md

@@ -0,0 +1,88 @@
+Guide to data types used by the Slate-based Rich Text Editor
+------------------------------------------------------------
+
+We always store the Slate editor state in its Value form.
+
+The schema for the Value is the same whether the editor is in MD or rich text mode, and is currently (rather arbitrarily)
+dictated by the schema expected by slate-md-serializer, simply because it was the only bit of the pipeline which
+has opinions on the schema. (slate-html-serializer lets you define how to serialize whatever schema you like).
+
+The BLOCK_TAGS and MARK_TAGS give the mapping from HTML tags to the schema's node types (for blocks, which describe
+block content like divs, and marks, which describe inline formatted sections like spans).
+
+We use <p/> as the parent tag for the message (XXX: although some tags are technically not allowed to be nested within p's)
+
+Various conversions are performed as content is moved between HTML, MD, and plaintext representations of HTML and MD.
+
+The primitives used are:
+
+ * Markdown.js - models commonmark-formatted MD strings (as entered by the composer in MD mode)
+   * toHtml() - renders them to HTML suitable for sending on the wire
+   * isPlainText() - checks whether the parsed MD contains anything other than simple text.
+   * toPlainText() - renders MD to plain text in order to remove backslashes.  Only works if the MD is already plaintext (otherwise it just emits HTML)
+
+ * slate-html-serializer
+   * converts Values to HTML (serialising) using our schema rules
+   * converts HTML to Values (deserialising) using our schema rules
+
+ * slate-md-serializer
+   * converts rich Values to MD strings (serialising) but using a non-commonmark generic MD dialect.
+   * This should use commonmark, but we use the serializer here for expedience rather than writing a commonmark one.
+
+ * slate-plain-serializer
+  * converts Values to plain text strings (serialising them) by concatenating the strings together
+  * converts Values from plain text strings (deserialiasing them).
+  * Used to initialise the editor by deserializing "" into a Value. Apparently this is the idiomatic way to initialise a blank editor.
+  * Used (as a bodge) to turn a rich text editor into a MD editor, when deserialising the converted MD string of the editor into a value
+
+ * PlainWithPillsSerializer
+  * A fork of slate-plain-serializer which is aware of Pills (hence the name) and Emoji.
+  * It can be configured to output Pills as:
+    * "plain": Pills are rendered via their 'completion' text - e.g. 'Matthew'; used for sending messages)
+    * "md": Pills are rendered as MD, e.g. [Matthew](https://matrix.to/#/@matthew:matrix.org) )
+    * "id": Pills are rendered as IDs, e.g. '@matthew:matrix.org' (used for authoring / commands)
+  * Emoji nodes are converted to inline utf8 emoji.
+
+The actual conversion transitions are:
+
+ * Quoting:
+   * The message being quoted is taken as HTML
+   * ...and deserialised into a Value
+   * ...and then serialised into MD via slate-md-serializer if the editor is in MD mode
+
+ * Roundtripping between MD and rich text editor mode
+   * From MD to richtext (mdToRichEditorState):
+     * Serialise the MD-format Value to a MD string (converting pills to MD) with PlainWithPillsSerializer in 'md' mode
+     * Convert that MD string to HTML via Markdown.js
+     * Deserialise that Value to HTML via slate-html-serializer
+   * From richtext to MD (richToMdEditorState):
+     * Serialise the richtext-format Value to a MD string with slate-md-serializer (XXX: this should use commonmark)
+     * Deserialise that to a plain text value via slate-plain-serializer
+
+ * Loading history in one format into an editor which is in the other format
+   * Uses the same functions as for roundtripping
+
+ * Scanning the editor for a slash command
+   * If the editor is a single line node starting with /, then serialize it to a string with PlainWithPillsSerializer in 'id' mode
+     So that pills get converted to IDs suitable for commands being passed around
+
+ * Sending messages
+   * In RT mode:
+     * If there is rich content, serialize the RT-format Value to HTML body via slate-html-serializer
+     * Serialize the RT-format Value to the plain text fallback via PlainWithPillsSerializer in 'plain' mode
+   * In MD mode:
+     * Serialize the MD-format Value into an MD string with PlainWithPillsSerializer in 'md' mode
+     * Parse the string with Markdown.js
+     * If it contains no formatting:
+       * Send as plaintext (as taken from Markdown.toPlainText())
+     * Otherwise
+       * Send as HTML (as taken from Markdown.toHtml())
+       * Serialize the RT-format Value to the plain text fallback via PlainWithPillsSerializer in 'plain' mode
+
+ * Pasting HTML
+   * Deserialize HTML to a RT Value via slate-html-serializer
+   * In RT mode, insert it straight into the editor as a fragment
+   * In MD mode, serialise it to an MD string via slate-md-serializer and then insert the string into the editor as a fragment.
+
+The various scenarios and transitions could be drawn into a pretty diagram if one felt the urge, but hopefully the above
+gives sufficient detail on how it's all meant to work.

package.json

@@ -59,9 +59,6 @@
     "classnames": "^2.1.2",
     "commonmark": "^0.28.1",
     "counterpart": "^0.18.0",
-    "draft-js": "^0.11.0-alpha",
-    "draft-js-export-html": "^0.6.0",
-    "draft-js-export-markdown": "^0.3.0",
     "emojione": "2.2.7",
     "file-saver": "^1.3.3",
     "filesize": "3.5.6",
@@ -87,6 +84,10 @@
     "react-beautiful-dnd": "^4.0.1",
     "react-dom": "^15.6.0",
     "react-gemini-scrollbar": "matrix-org/react-gemini-scrollbar#5e97aef",
+    "slate": "0.33.4",
+    "slate-react": "^0.12.4",
+    "slate-html-serializer": "^0.6.1",
+    "slate-md-serializer": "matrix-org/slate-md-serializer#f7c4ad3",
     "sanitize-html": "^1.14.1",
     "text-encoding-utf-8": "^1.0.1",
     "url": "^0.11.0",

res/css/_common.scss

@@ -291,6 +291,10 @@ textarea {
     vertical-align: middle;
 }
 
+.mx_emojione_selected {
+    background-color: $accent-color;
+}
+
 ::-moz-selection {
     background-color: $accent-color;
     color: $selection-fg-color;

res/css/structures/_RoomView.scss

@@ -176,10 +176,7 @@ hr.mx_RoomView_myReadMarker {
     z-index: 1000;
     overflow: hidden;
 
-    -webkit-transition: all .2s ease-out;
-    -moz-transition: all .2s ease-out;
-    -ms-transition: all .2s ease-out;
-    -o-transition: all .2s ease-out;
+    transition: all .2s ease-out;
 }
 
 .mx_RoomView_statusArea_expanded {

res/css/views/elements/_RichText.scss

@@ -27,6 +27,10 @@
     padding-right: 5px;
 }
 
+.mx_UserPill_selected {
+    background-color: $accent-color ! important;
+}
+
 .mx_EventTile_highlight .mx_EventTile_content .markdown-body a.mx_UserPill_me,
 .mx_EventTile_content .mx_AtRoomPill,
 .mx_MessageComposer_input .mx_AtRoomPill {

res/css/views/rooms/_EventTile.scss

@@ -448,6 +448,7 @@ limitations under the License.
 .mx_EventTile_content .markdown-body h2
 {
     font-size: 1.5em;
+    border-bottom: none ! important; // override GFM
 }
 
 .mx_EventTile_content .markdown-body a {

res/css/views/rooms/_MessageComposer.scss

@@ -79,12 +79,29 @@ limitations under the License.
     display: flex;
     flex-direction: column;
     min-height: 60px;
-    justify-content: center;
+    justify-content: start;
     align-items: flex-start;
     font-size: 14px;
     margin-right: 6px;
 }
 
+.mx_MessageComposer_editor {
+    width: 100%;
+    max-height: 120px;
+    min-height: 19px;
+    overflow: auto;
+    word-break: break-word;
+}
+
+// FIXME: rather unpleasant hack to get rid of <p/> margins.
+// really we should be mixing in markdown-body from gfm.css instead
+.mx_MessageComposer_editor > :first-child {
+    margin-top: 0 ! important;
+}
+.mx_MessageComposer_editor > :last-child {
+    margin-bottom: 0 ! important;
+}
+
 @keyframes visualbell
 {
     from { background-color: #faa }
@@ -95,36 +112,14 @@ limitations under the License.
     animation: 0.2s visualbell;
 }
 
-.mx_MessageComposer_input_empty .public-DraftEditorPlaceholder-root {
-    display: none;
-}
-
-.mx_MessageComposer_input .DraftEditor-root {
-    width: 100%;
-    flex: 1;
-    word-break: break-word;
-    max-height: 120px;
-    min-height: 21px;
-    overflow: auto;
-}
-
-.mx_MessageComposer_input .DraftEditor-root .DraftEditor-editorContainer {
-    /* Ensure mx_UserPill and mx_RoomPill (see _RichText) are not obscured from the top */
-    padding-top: 2px;
-}
-
-.mx_MessageComposer .public-DraftStyleDefault-block {
-    overflow-x: hidden;
-}
-
 .mx_MessageComposer_input blockquote {
     color: $blockquote-fg-color;
     margin: 0 0 16px;
     padding: 0 15px;
     border-left: 4px solid $blockquote-bar-color;
 }
 
-.mx_MessageComposer_input pre.public-DraftStyleDefault-pre pre {
+.mx_MessageComposer_input pre {
     background-color: $rte-code-bg-color;
     border-radius: 3px;
     padding: 10px;

src/ComposerHistoryManager.js

@@ -15,70 +15,73 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import {ContentState, convertToRaw, convertFromRaw} from 'draft-js';
-import * as RichText from './RichText';
-import Markdown from './Markdown';
+import { Value } from 'slate';
+
 import _clamp from 'lodash/clamp';
 
-type MessageFormat = 'html' | 'markdown';
+type MessageFormat = 'rich' | 'markdown';
 
 class HistoryItem {
 
-    // Keeping message for backwards-compatibility
-    message: string;
-    rawContentState: RawDraftContentState;
-    format: MessageFormat = 'html';
+    // We store history items in their native format to ensure history is accurate
+    // and then convert them if our RTE has subsequently changed format.
+    value: Value;
+    format: MessageFormat = 'rich';
 
-    constructor(contentState: ?ContentState, format: ?MessageFormat) {
-        this.rawContentState = contentState ? convertToRaw(contentState) : null;
+    constructor(value: ?Value, format: ?MessageFormat) {
+        this.value = value;
         this.format = format;
     }
 
-    toContentState(outputFormat: MessageFormat): ContentState {
-        const contentState = convertFromRaw(this.rawContentState);
-        if (outputFormat === 'markdown') {
-            if (this.format === 'html') {
-                return ContentState.createFromText(RichText.stateToMarkdown(contentState));
-            }
-        } else {
-            if (this.format === 'markdown') {
-                return RichText.htmlToContentState(new Markdown(contentState.getPlainText()).toHTML());
-            }
-        }
-        // history item has format === outputFormat
-        return contentState;
+    static fromJSON(obj: Object): HistoryItem {
+        return new HistoryItem(
+            Value.fromJSON(obj.value),
+            obj.format,
+        );
+    }
+
+    toJSON(): Object {
+        return {
+            value: this.value.toJSON(),
+            format: this.format,
+        };
     }
 }
 
 export default class ComposerHistoryManager {
     history: Array<HistoryItem> = [];
     prefix: string;
-    lastIndex: number = 0;
-    currentIndex: number = 0;
+    lastIndex: number = 0; // used for indexing the storage
+    currentIndex: number = 0; // used for indexing the loaded validated history Array
 
     constructor(roomId: string, prefix: string = 'mx_composer_history_') {
         this.prefix = prefix + roomId;
 
         // TODO: Performance issues?
         let item;
         for (; item = sessionStorage.getItem(`${this.prefix}[${this.currentIndex}]`); this.currentIndex++) {
-            this.history.push(
-                Object.assign(new HistoryItem(), JSON.parse(item)),
-            );
+            try {
+                this.history.push(
+                    HistoryItem.fromJSON(JSON.parse(item)),
+                );
+            } catch (e) {
+                console.warn("Throwing away unserialisable history", e);
+            }
         }
         this.lastIndex = this.currentIndex;
+        // reset currentIndex to account for any unserialisable history
+        this.currentIndex = this.history.length;
     }
 
-    save(contentState: ContentState, format: MessageFormat) {
-        const item = new HistoryItem(contentState, format);
+    save(value: Value, format: MessageFormat) {
+        const item = new HistoryItem(value, format);
         this.history.push(item);
-        this.currentIndex = this.lastIndex + 1;
-        sessionStorage.setItem(`${this.prefix}[${this.lastIndex++}]`, JSON.stringify(item));
+        this.currentIndex = this.history.length;
+        sessionStorage.setItem(`${this.prefix}[${this.lastIndex++}]`, JSON.stringify(item.toJSON()));
     }
 
-    getItem(offset: number, format: MessageFormat): ?ContentState {
-        this.currentIndex = _clamp(this.currentIndex + offset, 0, this.lastIndex - 1);
-        const item = this.history[this.currentIndex];
-        return item ? item.toContentState(format) : null;
+    getItem(offset: number): ?HistoryItem {
+        this.currentIndex = _clamp(this.currentIndex + offset, 0, this.history.length - 1);
+        return this.history[this.currentIndex];
     }
 }