TelegramPWA/src/lib/teact/teact-dom.ts
2022-09-16 18:28:44 +02:00

688 lines
20 KiB
TypeScript

import type {
VirtualElement,
VirtualElementComponent,
VirtualElementTag,
VirtualElementParent,
VirtualElementChildren,
VirtualElementReal,
VirtualElementFragment,
} from './teact';
import {
hasElementChanged,
isComponentElement,
isTagElement,
isParentElement,
isTextElement,
isEmptyElement,
mountComponent,
renderComponent,
unmountComponent,
isFragmentElement,
} from './teact';
import generateIdFor from '../../util/generateIdFor';
import { DEBUG } from '../../config';
import { addEventListener, removeAllDelegatedListeners, removeEventListener } from './dom-events';
import { unique } from '../../util/iteratees';
type VirtualDomHead = {
children: [VirtualElement] | [];
};
const FILTERED_ATTRIBUTES = new Set(['key', 'ref', 'teactFastList', 'teactOrderKey']);
const HTML_ATTRIBUTES = new Set(['dir', 'role', 'form']);
const CONTROLLABLE_TAGS = ['INPUT', 'TEXTAREA', 'SELECT'];
const MAPPED_ATTRIBUTES: { [k: string]: string } = {
autoPlay: 'autoplay',
autoComplete: 'autocomplete',
};
const INDEX_KEY_PREFIX = '__indexKey#';
const headsByElement: Record<string, VirtualDomHead> = {};
// eslint-disable-next-line @typescript-eslint/naming-convention
let DEBUG_virtualTreeSize = 1;
function render($element: VirtualElement | undefined, parentEl: HTMLElement) {
let headId = parentEl.getAttribute('data-teact-head-id');
if (!headId) {
headId = generateIdFor(headsByElement);
headsByElement[headId] = { children: [] };
parentEl.setAttribute('data-teact-head-id', headId);
}
const $head = headsByElement[headId];
const $newElement = renderWithVirtual(parentEl, $head.children[0], $element, $head, 0);
$head.children = $newElement ? [$newElement] : [];
if (process.env.APP_ENV === 'perf') {
DEBUG_virtualTreeSize = 0;
DEBUG_addToVirtualTreeSize($head);
return DEBUG_virtualTreeSize;
}
return undefined;
}
function renderWithVirtual<T extends VirtualElement | undefined>(
parentEl: HTMLElement,
$current: VirtualElement | undefined,
$new: T,
$parent: VirtualElementParent | VirtualDomHead,
index: number,
options: {
skipComponentUpdate?: boolean;
nextSibling?: ChildNode;
fragment?: DocumentFragment;
} = {},
): T {
const { skipComponentUpdate, fragment } = options;
let { nextSibling } = options;
const isCurrentComponent = $current && isComponentElement($current);
const isNewComponent = $new && isComponentElement($new);
const $newAsReal = $new as VirtualElementReal;
const isCurrentFragment = $current && !isCurrentComponent && isFragmentElement($current);
const isNewFragment = $new && !isNewComponent && isFragmentElement($new);
if (
!skipComponentUpdate
&& isCurrentComponent && isNewComponent
&& !hasElementChanged($current!, $new!)
) {
$new = updateComponent($current, $new as VirtualElementComponent) as typeof $new;
}
// Parent element may have changed, so we need to update the listener closure.
if (!skipComponentUpdate && isNewComponent && ($new as VirtualElementComponent).componentInstance.isMounted) {
setupComponentUpdateListener(parentEl, $new as VirtualElementComponent, $parent, index);
}
if ($current === $new) {
return $new;
}
if (DEBUG && $new) {
const newTarget = 'target' in $new && $new.target;
if (newTarget && (!$current || ('target' in $current && newTarget !== $current.target))) {
throw new Error('[Teact] Cached virtual element was moved within tree');
}
}
if (!$current && $new) {
if (isNewComponent || isNewFragment) {
if (isNewComponent) {
$new = initComponent(parentEl, $new as VirtualElementComponent, $parent, index) as typeof $new;
}
mountChildren(parentEl, $new as VirtualElementComponent | VirtualElementFragment, { nextSibling, fragment });
} else {
const node = createNode($newAsReal);
$newAsReal.target = node;
insertBefore(fragment || parentEl, node, nextSibling);
}
} else if ($current && !$new) {
remount(parentEl, $current, undefined);
} else if ($current && $new) {
if (hasElementChanged($current, $new)) {
if (!nextSibling) {
nextSibling = getNextSibling($current);
}
if (isNewComponent || isNewFragment) {
if (isNewComponent) {
$new = initComponent(parentEl, $new as VirtualElementComponent, $parent, index) as typeof $new;
}
remount(parentEl, $current, undefined);
mountChildren(parentEl, $new as VirtualElementComponent | VirtualElementFragment, { nextSibling, fragment });
} else {
const node = createNode($newAsReal);
$newAsReal.target = node;
remount(parentEl, $current, node, nextSibling);
}
} else {
const isComponent = isCurrentComponent && isNewComponent;
const isFragment = isCurrentFragment && isNewFragment;
if (isComponent || isFragment) {
($new as VirtualElementComponent | VirtualElementFragment).children = renderChildren(
$current,
$new as VirtualElementComponent | VirtualElementFragment,
parentEl,
nextSibling,
);
} else {
const $currentAsReal = $current as VirtualElementReal;
const currentTarget = $currentAsReal.target!;
$newAsReal.target = currentTarget;
$currentAsReal.target = undefined; // Help GC
const isTag = isTagElement($current);
if (isTag) {
const $newAsTag = $new as VirtualElementTag;
$newAsTag.props.ref = $current.props.ref;
if (nextSibling) {
insertBefore(parentEl, currentTarget, nextSibling);
}
updateAttributes($current, $newAsTag, currentTarget as HTMLElement);
$newAsTag.children = renderChildren(
$current,
$newAsTag,
currentTarget as HTMLElement,
);
}
}
}
}
return $new;
}
function initComponent(
parentEl: HTMLElement,
$element: VirtualElementComponent,
$parent: VirtualElementParent | VirtualDomHead,
index: number,
) {
const { componentInstance } = $element;
if (!componentInstance.isMounted) {
$element = mountComponent(componentInstance);
setupComponentUpdateListener(parentEl, $element, $parent, index);
const $firstChild = $element.children[0];
if (isComponentElement($firstChild)) {
$element.children = [initComponent(parentEl, $firstChild, $element, 0)];
}
componentInstance.isMounted = true;
}
return $element;
}
function updateComponent($current: VirtualElementComponent, $new: VirtualElementComponent) {
$current.componentInstance.props = $new.componentInstance.props;
return renderComponent($current.componentInstance);
}
function setupComponentUpdateListener(
parentEl: HTMLElement,
$element: VirtualElementComponent,
$parent: VirtualElementParent | VirtualDomHead,
index: number,
) {
const { componentInstance } = $element;
componentInstance.onUpdate = () => {
$parent.children[index] = renderWithVirtual(
parentEl,
$parent.children[index],
componentInstance.$element,
$parent,
index,
{ skipComponentUpdate: true },
);
};
}
function mountChildren(
parentEl: HTMLElement,
$element: VirtualElementComponent | VirtualElementFragment,
options: {
nextSibling?: ChildNode;
fragment?: DocumentFragment;
},
) {
$element.children = $element.children.map(($child, i) => {
return renderWithVirtual(parentEl, undefined, $child, $element, i, options);
});
}
function unmountChildren(parentEl: HTMLElement, $element: VirtualElementComponent | VirtualElementFragment) {
$element.children.forEach(($child) => {
renderWithVirtual(parentEl, $child, undefined, $element, -1);
});
}
function createNode($element: VirtualElementReal): Node {
if (isEmptyElement($element)) {
return document.createTextNode('');
}
if (isTextElement($element)) {
return document.createTextNode($element.value);
}
const { tag, props, children = [] } = $element;
const element = document.createElement(tag);
if (typeof props.ref === 'object') {
props.ref.current = element;
}
processControlled(tag, props);
Object.entries(props).forEach(([key, value]) => {
if (props[key] !== undefined) {
setAttribute(element, key, value);
}
});
processUncontrolledOnMount(element, props);
$element.children = children.map(($child, i) => (
renderWithVirtual(element, undefined, $child, $element, i)
));
return element;
}
function remount(
parentEl: HTMLElement,
$current: VirtualElement,
node: Node | undefined,
componentNextSibling?: ChildNode,
) {
const isComponent = isComponentElement($current);
const isFragment = !isComponent && isFragmentElement($current);
if (isComponent || isFragment) {
if (isComponent) {
unmountComponent($current.componentInstance);
}
unmountChildren(parentEl, $current);
if (node) {
insertBefore(parentEl, node, componentNextSibling);
}
} else {
if (node) {
parentEl.replaceChild(node, $current.target!);
} else {
parentEl.removeChild($current.target!);
}
unmountRealTree($current);
}
}
export function unmountRealTree($element: VirtualElement) {
if (isComponentElement($element)) {
unmountComponent($element.componentInstance);
} else {
if (isTagElement($element)) {
if ($element.target) {
removeAllDelegatedListeners($element.target as HTMLElement);
if ($element.props.ref?.current === $element.target) {
$element.props.ref.current = undefined;
}
}
}
if ($element.target) {
$element.target = undefined; // Help GC
}
if (!isParentElement($element)) {
return;
}
}
$element.children.forEach(unmountRealTree);
}
function insertBefore(parentEl: HTMLElement | DocumentFragment, node: Node, nextSibling?: ChildNode) {
if (nextSibling) {
parentEl.insertBefore(node, nextSibling);
} else {
parentEl.appendChild(node);
}
}
function getNextSibling($current: VirtualElement): ChildNode | undefined {
if (isComponentElement($current) || isFragmentElement($current)) {
const lastChild = $current.children[$current.children.length - 1];
return getNextSibling(lastChild);
}
const target = $current.target!;
const { nextSibling } = target;
return nextSibling || undefined;
}
function renderChildren(
$current: VirtualElementParent, $new: VirtualElementParent, currentEl: HTMLElement, nextSibling?: ChildNode,
) {
if (DEBUG) {
DEBUG_checkKeyUniqueness($new.children);
}
if (('props' in $new) && $new.props.teactFastList) {
return renderFastListChildren($current, $new, currentEl);
}
const currentChildrenLength = $current.children.length;
const newChildrenLength = $new.children.length;
const maxLength = Math.max(currentChildrenLength, newChildrenLength);
const newChildren = [];
const fragment = newChildrenLength > currentChildrenLength ? document.createDocumentFragment() : undefined;
const lastCurrentChild = $current.children[currentChildrenLength - 1];
const fragmentNextSibling = nextSibling || (
newChildrenLength > currentChildrenLength && lastCurrentChild ? getNextSibling(lastCurrentChild) : undefined
);
for (let i = 0; i < maxLength; i++) {
const $newChild = renderWithVirtual(
currentEl,
$current.children[i],
$new.children[i],
$new,
i,
i >= currentChildrenLength ? { fragment } : { nextSibling },
);
if ($newChild) {
newChildren.push($newChild);
}
}
if (fragment) {
insertBefore(currentEl, fragment, fragmentNextSibling);
}
return newChildren;
}
// This function allows to prepend/append a bunch of new DOM nodes to the top/bottom of preserved ones.
// It also allows to selectively move particular preserved nodes within their DOM list.
function renderFastListChildren($current: VirtualElementParent, $new: VirtualElementParent, currentEl: HTMLElement) {
const newKeys = new Set(
$new.children.map(($newChild) => {
const key = 'props' in $newChild && $newChild.props.key;
if (DEBUG && isParentElement($newChild)) {
// eslint-disable-next-line no-null/no-null
if (key === undefined || key === null) {
// eslint-disable-next-line no-console
console.warn('Missing `key` in `teactFastList`');
}
if (isFragmentElement($newChild)) {
throw new Error('[Teact] Fragment can not be child of container with `teactFastList`');
}
}
return key;
}),
);
// Build a collection of old children that also remain in the new list
let currentRemainingIndex = 0;
const remainingByKey = $current.children
.reduce((acc, $currentChild, i) => {
let key = 'props' in $currentChild ? $currentChild.props.key : undefined;
// eslint-disable-next-line no-null/no-null
const isKeyPresent = key !== undefined && key !== null;
// First we process removed children
if (isKeyPresent && !newKeys.has(key)) {
renderWithVirtual(currentEl, $currentChild, undefined, $new, -1);
return acc;
} else if (!isKeyPresent) {
const $newChild = $new.children[i];
const newChildKey = ($newChild && 'props' in $newChild) ? $newChild.props.key : undefined;
// If a non-key element remains at the same index we preserve it with a virtual `key`
if ($newChild && !newChildKey) {
key = `${INDEX_KEY_PREFIX}${i}`;
// Otherwise, we just remove it
} else {
renderWithVirtual(currentEl, $currentChild, undefined, $new, -1);
return acc;
}
}
// Then we build up info about remaining children
acc[key] = {
$element: $currentChild,
index: currentRemainingIndex++,
orderKey: 'props' in $currentChild ? $currentChild.props.teactOrderKey : undefined,
};
return acc;
}, {} as Record<string, { $element: VirtualElement; index: number; orderKey?: number }>);
let newChildren: VirtualElement[] = [];
let fragmentElements: VirtualElement[] | undefined;
let fragmentIndex: number | undefined;
let currentPreservedIndex = 0;
$new.children.forEach(($newChild, i) => {
const key = 'props' in $newChild ? $newChild.props.key : `${INDEX_KEY_PREFIX}${i}`;
const currentChildInfo = remainingByKey[key];
if (!currentChildInfo) {
if (!fragmentElements) {
fragmentElements = [];
fragmentIndex = i;
}
fragmentElements.push($newChild);
return;
}
// This prepends new children to the top
if (fragmentElements) {
newChildren = newChildren.concat(renderFragment(fragmentElements, fragmentIndex!, currentEl, $new));
fragmentElements = undefined;
fragmentIndex = undefined;
}
// Now we check if a preserved node was moved within preserved list
const newOrderKey = 'props' in $newChild ? $newChild.props.teactOrderKey : undefined;
// That is indicated by a changed `teactOrderKey` value
const shouldMoveNode = (
currentChildInfo.index !== currentPreservedIndex && currentChildInfo.orderKey !== newOrderKey
);
const isMovingDown = shouldMoveNode && currentPreservedIndex > currentChildInfo.index;
if (!shouldMoveNode || isMovingDown) {
currentPreservedIndex++;
}
newChildren.push(
renderWithVirtual(currentEl, currentChildInfo.$element, $newChild, $new, i, {
// `+ 1` is needed because before moving down the node still takes place above
nextSibling: shouldMoveNode ? currentEl.childNodes[isMovingDown ? i + 1 : i] : undefined,
}),
);
});
// This appends new children to the bottom
if (fragmentElements) {
newChildren = newChildren.concat(renderFragment(fragmentElements, fragmentIndex!, currentEl, $new));
}
return newChildren;
}
function renderFragment(
elements: VirtualElement[], fragmentIndex: number, parentEl: HTMLElement, $parent: VirtualElementParent,
) {
const nextSibling = parentEl.childNodes[fragmentIndex];
if (elements.length === 1) {
return [renderWithVirtual(parentEl, undefined, elements[0], $parent, fragmentIndex, { nextSibling })];
}
const fragment = document.createDocumentFragment();
const newChildren = elements.map(($element, i) => (
renderWithVirtual(parentEl, undefined, $element, $parent, fragmentIndex + i, { fragment })
));
insertBefore(parentEl, fragment, nextSibling);
return newChildren;
}
function processControlled(tag: string, props: AnyLiteral) {
// TODO Remove after tests
if (!props.teactExperimentControlled) {
return;
}
const isValueControlled = props.value !== undefined;
const isCheckedControlled = props.checked !== undefined;
const isControlled = (isValueControlled || isCheckedControlled) && CONTROLLABLE_TAGS.includes(tag.toUpperCase());
if (!isControlled) {
return;
}
const {
value, checked, onInput, onChange,
} = props;
props.onChange = undefined;
props.onInput = (e: React.ChangeEvent<HTMLInputElement>) => {
onInput?.(e);
onChange?.(e);
if (value !== undefined) {
e.currentTarget.value = value;
}
if (checked !== undefined) {
e.currentTarget.checked = checked;
}
};
}
function processUncontrolledOnMount(element: HTMLElement, props: AnyLiteral) {
if (!CONTROLLABLE_TAGS.includes(element.tagName)) {
return;
}
if (props.defaultValue) {
setAttribute(element, 'value', props.defaultValue);
}
if (props.defaultChecked) {
setAttribute(element, 'checked', props.defaultChecked);
}
}
function updateAttributes($current: VirtualElementTag, $new: VirtualElementTag, element: HTMLElement) {
processControlled(element.tagName, $new.props);
const currentEntries = Object.entries($current.props);
const newEntries = Object.entries($new.props);
currentEntries.forEach(([key, currentValue]) => {
const newValue = $new.props[key];
if (
currentValue !== undefined
&& (
newValue === undefined
|| (currentValue !== newValue && key.startsWith('on'))
)
) {
removeAttribute(element, key, currentValue);
}
});
newEntries.forEach(([key, newValue]) => {
const currentValue = $current.props[key];
if (newValue !== undefined && newValue !== currentValue) {
setAttribute(element, key, newValue);
}
});
}
function setAttribute(element: HTMLElement, key: string, value: any) {
// An optimization attempt
if (key === 'className') {
element.className = value;
// An optimization attempt
} else if (key === 'value') {
if ((element as HTMLInputElement).value !== value) {
(element as HTMLInputElement).value = value;
}
} else if (key === 'style') {
element.style.cssText = value;
} else if (key === 'dangerouslySetInnerHTML') {
// eslint-disable-next-line no-underscore-dangle
element.innerHTML = value.__html;
} else if (key.startsWith('on')) {
addEventListener(element, key, value, key.endsWith('Capture'));
} else if (key.startsWith('data-') || key.startsWith('aria-') || HTML_ATTRIBUTES.has(key)) {
element.setAttribute(key, value);
} else if (!FILTERED_ATTRIBUTES.has(key)) {
(element as any)[MAPPED_ATTRIBUTES[key] || key] = value;
}
}
function removeAttribute(element: HTMLElement, key: string, value: any) {
if (key === 'className') {
element.className = '';
} else if (key === 'value') {
(element as HTMLInputElement).value = '';
} else if (key === 'style') {
element.style.cssText = '';
} else if (key === 'dangerouslySetInnerHTML') {
element.innerHTML = '';
} else if (key.startsWith('on')) {
removeEventListener(element, key, value, key.endsWith('Capture'));
} else if (key.startsWith('data-') || key.startsWith('aria-') || HTML_ATTRIBUTES.has(key)) {
element.removeAttribute(key);
} else if (!FILTERED_ATTRIBUTES.has(key)) {
delete (element as any)[MAPPED_ATTRIBUTES[key] || key];
}
}
// eslint-disable-next-line @typescript-eslint/naming-convention
function DEBUG_addToVirtualTreeSize($current: VirtualElementParent | VirtualDomHead) {
DEBUG_virtualTreeSize += $current.children.length;
$current.children.forEach(($child) => {
if (isParentElement($child)) {
DEBUG_addToVirtualTreeSize($child);
}
});
}
// eslint-disable-next-line @typescript-eslint/naming-convention
function DEBUG_checkKeyUniqueness(children: VirtualElementChildren) {
const firstChild = children[0];
if (firstChild && 'props' in firstChild && firstChild.props.key !== undefined) {
const keys = children.reduce((acc: any[], child) => {
if ('props' in child && child.props.key) {
acc.push(child.props.key);
}
return acc;
}, []);
if (keys.length !== unique(keys).length) {
throw new Error('[Teact] Children keys are not unique');
}
}
}
const TeactDOM = { render };
export default TeactDOM;