[GH-770] Use textarea for title in the card dialog (#776)

* New widget `EditableArea` introduced:
  - textarea with automatic height
  - implementation is based on AutosizeTextarea from mattermost-webapp
  - used for title in CardDetail

* Cypress test for setting card title fixed.

Co-authored-by: Harshil Sharma <harshilsharma63@gmail.com>

webapp/cypress/integration/createBoard.js

@@ -59,7 +59,7 @@ describe('Create and delete board / card', () => {
 
     it('Can set the card title', () => {
         // Card title
-        cy.get('.CardDetail>.Editable.title').
+        cy.get('.CardDetail .EditableArea.title').
             type(cardTitle).
             type('{enter}').
             should('have.value', cardTitle);

webapp/src/components/cardDetail/cardDetail.scss

@@ -1,4 +1,7 @@
 .CardDetail {
+    .title {
+        width: 100%;
+    }
 
     .add-buttons {
         display: flex;

webapp/src/components/cardDetail/cardDetail.tsx

@@ -8,7 +8,8 @@ import mutator from '../../mutator'
 import {BoardTree} from '../../viewModel/boardTree'
 import {CardTree} from '../../viewModel/cardTree'
 import Button from '../../widgets/buttons/button'
-import Editable from '../../widgets/editable'
+import {Focusable} from '../../widgets/editable'
+import EditableArea from '../../widgets/editableArea'
 import EmojiIcon from '../../widgets/icons/emoji'
 
 import BlockIconSelector from '../blockIconSelector'
@@ -30,7 +31,7 @@ const CardDetail = (props: Props): JSX.Element|null => {
     const {cardTree} = props
     const {card, comments} = cardTree
     const [title, setTitle] = useState(cardTree.card.title)
-    const titleRef = useRef<{focus(selectAll?: boolean): void}>(null)
+    const titleRef = useRef<Focusable>(null)
     const titleValueRef = useRef(title)
     titleValueRef.current = title
 
@@ -76,7 +77,7 @@ const CardDetail = (props: Props): JSX.Element|null => {
                         </Button>
                     </div>}
 
-                <Editable
+                <EditableArea
                     ref={titleRef}
                     className='title'
                     value={title}

webapp/src/widgets/editable.tsx

@@ -1,10 +1,10 @@
 // Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
 // See LICENSE.txt for license information.
-import React, {useRef, useImperativeHandle, forwardRef} from 'react'
+import React, {forwardRef, useImperativeHandle, useRef} from 'react'
 
 import './editable.scss'
 
-type Props = {
+export type EditableProps = {
     onChange: (value: string) => void
     value?: string
     placeholderText?: string
@@ -18,8 +18,28 @@ type Props = {
     onSave?: (saveType: 'onEnter'|'onEsc'|'onBlur') => void
 }
 
-const Editable = (props: Props, ref: React.Ref<{focus: (selectAll?: boolean) => void}>): JSX.Element => {
-    const elementRef = useRef<HTMLInputElement>(null)
+export type Focusable = {
+    focus: (selectAll?: boolean) => void
+}
+
+export type ElementType = HTMLInputElement | HTMLTextAreaElement
+
+export type ElementProps = {
+    className: string,
+    placeholder?: string,
+    onChange: (e: React.ChangeEvent<ElementType>) => void,
+    value?: string,
+    title?: string,
+    onBlur: () => void,
+    onKeyDown: (e: React.KeyboardEvent<ElementType>) => void,
+    readOnly?: boolean,
+    spellCheck?: boolean
+}
+
+export function useEditable(
+    props: EditableProps,
+    focusableRef: React.Ref<Focusable>,
+    elementRef: React.RefObject<ElementType>): ElementProps {
     const saveOnBlur = useRef<boolean>(true)
 
     const save = (saveType: 'onEnter'|'onEsc'|'onBlur'): void => {
@@ -38,7 +58,7 @@ const Editable = (props: Props, ref: React.Ref<{focus: (selectAll?: boolean) =>
         props.onSave(saveType)
     }
 
-    useImperativeHandle(ref, () => ({
+    useImperativeHandle(focusableRef, () => ({
         focus: (selectAll = false): void => {
             if (elementRef.current) {
                 const valueLength = elementRef.current.value.length
@@ -63,35 +83,42 @@ const Editable = (props: Props, ref: React.Ref<{focus: (selectAll?: boolean) =>
     if (props.validator) {
         error = !props.validator(value || '')
     }
+    return {
+        className: 'Editable ' + (error ? 'error ' : '') + (readonly ? 'readonly ' : '') + className,
+        placeholder: placeholderText,
+        onChange: (e: React.ChangeEvent<ElementType>) => {
+            onChange(e.target.value)
+        },
+        value,
+        title: value,
+        onBlur: () => save('onBlur'),
+        onKeyDown: (e: React.KeyboardEvent<ElementType>): void => {
+            if (e.keyCode === 27 && !(e.metaKey || e.ctrlKey) && !e.shiftKey && !e.altKey) { // ESC
+                e.preventDefault()
+                if (props.saveOnEsc) {
+                    save('onEsc')
+                } else {
+                    props.onCancel?.()
+                }
+                blur()
+            } else if (e.keyCode === 13 && !(e.metaKey || e.ctrlKey) && !e.shiftKey && !e.altKey) { // Return
+                e.preventDefault()
+                save('onEnter')
+                blur()
+            }
+        },
+        readOnly: readonly,
+        spellCheck: props.spellCheck,
+    }
+}
 
+const Editable = (props: EditableProps, ref: React.Ref<Focusable>): JSX.Element => {
+    const elementRef = useRef<HTMLInputElement>(null)
+    const elementProps = useEditable(props, ref, elementRef)
     return (
         <input
+            {...elementProps}
             ref={elementRef}
-            className={'Editable ' + (error ? 'error ' : '') + (readonly ? 'readonly ' : '') + className}
-            placeholder={placeholderText}
-            onChange={(e: React.ChangeEvent<HTMLInputElement>) => {
-                onChange(e.target.value)
-            }}
-            value={value}
-            title={value}
-            onBlur={() => save('onBlur')}
-            onKeyDown={(e: React.KeyboardEvent<HTMLInputElement>): void => {
-                if (e.keyCode === 27 && !(e.metaKey || e.ctrlKey) && !e.shiftKey && !e.altKey) { // ESC
-                    e.stopPropagation()
-                    if (props.saveOnEsc) {
-                        save('onEsc')
-                    } else {
-                        props.onCancel?.()
-                    }
-                    blur()
-                } else if (e.keyCode === 13 && !(e.metaKey || e.ctrlKey) && !e.shiftKey && !e.altKey) { // Return
-                    e.stopPropagation()
-                    save('onEnter')
-                    blur()
-                }
-            }}
-            readOnly={readonly}
-            spellCheck={props.spellCheck}
         />
     )
 }

webapp/src/widgets/editableArea.scss

@@ -0,0 +1,17 @@
+.EditableAreaWrap {
+    width: 100%;
+}
+
+.EditableArea {
+    resize: none;
+}
+
+.EditableAreaContainer {
+    height: 0;
+    overflow: hidden;
+}
+
+.EditableAreaReference {
+    height: auto;
+    width: 100%;
+}

webapp/src/widgets/editableArea.tsx

@@ -0,0 +1,66 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+import React, {forwardRef, useEffect, useRef} from 'react'
+
+import {EditableProps, Focusable, useEditable} from './editable'
+
+import './editableArea.scss'
+
+function getBorderWidth(style: CSSStyleDeclaration): number {
+    return parseInt(style.borderTopWidth || '0', 10) + parseInt(style.borderBottomWidth || '0', 10)
+}
+
+const EditableArea = (props: EditableProps, ref: React.Ref<Focusable>): JSX.Element => {
+    const elementRef = useRef<HTMLTextAreaElement>(null)
+    const referenceRef = useRef<HTMLTextAreaElement>(null)
+    const heightRef = useRef(0)
+    const elementProps = useEditable(props, ref, elementRef)
+
+    useEffect(() => {
+        if (!elementRef.current || !referenceRef.current) {
+            return
+        }
+
+        const height = referenceRef.current.scrollHeight
+        const textarea = elementRef.current
+
+        if (height > 0 && height !== heightRef.current) {
+            const style = getComputedStyle(textarea)
+            const borderWidth = getBorderWidth(style)
+
+            // Directly change the height to avoid circular rerenders
+            textarea.style.height = String(height + borderWidth) + 'px'
+
+            heightRef.current = height
+        }
+    })
+
+    const heightProps = {
+        height: heightRef.current,
+        rows: 1,
+    }
+
+    return (
+        <div className={'EditableAreaWrap'}>
+            <textarea
+                {...elementProps}
+                {...heightProps}
+                ref={elementRef}
+                className={'EditableArea ' + elementProps.className}
+            />
+            <div className={'EditableAreaContainer'}>
+                <textarea
+                    ref={referenceRef}
+                    className={'EditableAreaReference ' + elementProps.className}
+                    dir='auto'
+                    disabled={true}
+                    rows={1}
+                    value={elementProps.value}
+                    aria-hidden={true}
+                />
+            </div>
+        </div>
+    )
+}
+
+export default forwardRef(EditableArea)