fix(frontend): フォーカスの挙動を修正 (#14158)

* fix(frontend): 直前のパターンを記録するように

* fix(frontend): フォーカス/タブ移動に関する挙動を調整 (#226)

Cherry-pick commit e8c030673326871edf3623cf2b8675d68f9e1b13

Co-authored-by: taiyme <53635909+taiyme@users.noreply.github.com>

* focusのデザイン修正

* move scripts

* Modalにfocus trapを追加

* 記録するホットキーはレートリミット式にする

* escキーのハンドリングをMkModalに統一

* fix

* enterで子メニューを開けるように

* lint

* fix focus trap

* improve switch accessibility

* 一部のmodalのフォーカストラップが外れない問題を修正

* fix

* fix

* Revert "記録するホットキーはレートリミット式にする"

This reverts commit 40a7509286a87911ad4cc06d9482e8a2e5d0e7e8.

* Revert "fix(frontend): 直前のパターンを記録するように"

This reverts commit 5372b2594023952cff34aa62253ed4efef15b5dd.

* Revert "Revert "fix(frontend): 直前のパターンを記録するように""

This reverts commit a9bb52e799e110927ad92cd8f26af980819334e1.

* Revert "Revert "記録するホットキーはレートリミット式にする""

This reverts commit bdac34273e0bc5f13604c7e2f9fa6b1321a0df3d.

* 試験的にCypressでのFocustrapを無効化

* fix

* fix focus-trap

* Update Changelog

* :v:

* fix focustrap invocation logic

* スクロールがsticky headerを考慮するように

* :art:

* スタイルの微調整

* :art:

* remove deprecated key aliases

* focusElementが足りなかったので修正

* preview系にfocus時スタイルが足りなかったので修正

* `returnFocusElement` -> `returnFocusTo`

* lint

* Update packages/frontend/src/components/MkModalWindow.vue

* Apply suggestions from code review

Co-authored-by: taiy <53635909+taiyme@users.noreply.github.com>

* keydownイベントをまとめる

* use correct pesudo-element selector

* fix

* rename

---------

Co-authored-by: taiyme <53635909+taiyme@users.noreply.github.com>
Co-authored-by: syuilo <4439005+syuilo@users.noreply.github.com>

5 files changed, 207 insertions, 30 deletions

diff --git a/packages/frontend/src/scripts/focus-trap.ts b/packages/frontend/src/scripts/focus-trap.ts
new file mode 100644
index 0000000000..734c73652f
--- /dev/null
+++ b/packages/frontend/src/scripts/focus-trap.ts
@@ -0,0 +1,65 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { getHTMLElementOrNull } from '@/scripts/get-dom-node-or-null.js';
+
+const focusTrapElements = new Set<HTMLElement>();
+const ignoreElements = [
+	'script',
+	'style',
+];
+
+function containsFocusTrappedElements(el: HTMLElement): boolean {
+	return Array.from(focusTrapElements).some((focusTrapElement) => {
+		return el.contains(focusTrapElement);
+	});
+}
+
+function releaseFocusTrap(el: HTMLElement): void {
+	focusTrapElements.delete(el);
+	if (el.parentElement != null && el !== document.body) {
+		el.parentElement.childNodes.forEach((siblingNode) => {
+			const siblingEl = getHTMLElementOrNull(siblingNode);
+			if (!siblingEl) return;
+			if (siblingEl !== el && (focusTrapElements.has(siblingEl) || containsFocusTrappedElements(siblingEl) || focusTrapElements.size === 0)) {
+				siblingEl.inert = false;
+			} else if (
+				focusTrapElements.size > 0 &&
+				!containsFocusTrappedElements(siblingEl) &&
+				!focusTrapElements.has(siblingEl) &&
+				!ignoreElements.includes(siblingEl.tagName.toLowerCase())
+			) {
+				siblingEl.inert = true;
+			} else {
+				siblingEl.inert = false;
+			}
+		});
+		releaseFocusTrap(el.parentElement);
+	}
+}
+
+export function focusTrap(el: HTMLElement, parent: true): void;
+export function focusTrap(el: HTMLElement, parent?: false): { release: () => void; };
+export function focusTrap(el: HTMLElement, parent = false): { release: () => void; } | void {
+	if (el.parentElement != null && el !== document.body) {
+		el.parentElement.childNodes.forEach((siblingNode) => {
+			const siblingEl = getHTMLElementOrNull(siblingNode);
+			if (!siblingEl) return;
+			if (siblingEl !== el && !ignoreElements.includes(siblingEl.tagName.toLowerCase())) {
+				siblingEl.inert = true;
+			}
+		});
+		focusTrap(el.parentElement, true);
+	}
+
+	if (!parent) {
+		focusTrapElements.add(el);
+
+		return {
+			release: () => {
+				releaseFocusTrap(el);
+			},
+		};
+	}
+}
diff --git a/packages/frontend/src/scripts/focus.ts b/packages/frontend/src/scripts/focus.ts
index ea6ee61c88..eb2da5ad86 100644
--- a/packages/frontend/src/scripts/focus.ts
+++ b/packages/frontend/src/scripts/focus.ts
@@ -3,30 +3,78 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
-export function focusPrev(el: Element | null, self = false, scroll = true) {
-	if (el == null) return;
-	if (!self) el = el.previousElementSibling;
-	if (el) {
-		if (el.hasAttribute('tabindex')) {
-			(el as HTMLElement).focus({
-				preventScroll: !scroll,
-			});
-		} else {
-			focusPrev(el.previousElementSibling, true);
-		}
+import { getScrollPosition, getScrollContainer, getStickyBottom, getStickyTop } from '@/scripts/scroll.js';
+import { getElementOrNull, getNodeOrNull } from '@/scripts/get-dom-node-or-null.js';
+
+type MaybeHTMLElement = EventTarget | Node | Element | HTMLElement;
+
+export const isFocusable = (input: MaybeHTMLElement | null | undefined): input is HTMLElement => {
+	if (input == null || !(input instanceof HTMLElement)) return false;
+
+	if (input.tabIndex < 0) return false;
+	if ('disabled' in input && input.disabled === true) return false;
+	if ('readonly' in input && input.readonly === true) return false;
+
+	if (!input.ownerDocument.contains(input)) return false;
+
+	const style = window.getComputedStyle(input);
+	if (style.display === 'none') return false;
+	if (style.visibility === 'hidden') return false;
+	if (style.opacity === '0') return false;
+	if (style.pointerEvents === 'none') return false;
+
+	return true;
+};
+
+export const focusPrev = (input: MaybeHTMLElement | null | undefined, self = false, scroll = true) => {
+	const element = self ? input : getElementOrNull(input)?.previousElementSibling;
+	if (element == null) return;
+	if (isFocusable(element)) {
+		focusOrScroll(element, scroll);
+	} else {
+		focusPrev(element, false, scroll);
 	}
-}
+};
 
-export function focusNext(el: Element | null, self = false, scroll = true) {
-	if (el == null) return;
-	if (!self) el = el.nextElementSibling;
-	if (el) {
-		if (el.hasAttribute('tabindex')) {
-			(el as HTMLElement).focus({
-				preventScroll: !scroll,
-			});
-		} else {
-			focusPrev(el.nextElementSibling, true);
+export const focusNext = (input: MaybeHTMLElement | null | undefined, self = false, scroll = true) => {
+	const element = self ? input : getElementOrNull(input)?.nextElementSibling;
+	if (element == null) return;
+	if (isFocusable(element)) {
+		focusOrScroll(element, scroll);
+	} else {
+		focusNext(element, false, scroll);
+	}
+};
+
+export const focusParent = (input: MaybeHTMLElement | null | undefined, self = false, scroll = true) => {
+	const element = self ? input : getNodeOrNull(input)?.parentElement;
+	if (element == null) return;
+	if (isFocusable(element)) {
+		focusOrScroll(element, scroll);
+	} else {
+		focusParent(element, false, scroll);
+	}
+};
+
+const focusOrScroll = (element: HTMLElement, scroll: boolean) => {
+	if (scroll) {
+		const scrollContainer = getScrollContainer(element) ?? document.documentElement;
+		const scrollContainerTop = getScrollPosition(scrollContainer);
+		const stickyTop = getStickyTop(element, scrollContainer);
+		const stickyBottom = getStickyBottom(element, scrollContainer);
+		const top = element.getBoundingClientRect().top;
+		const bottom = element.getBoundingClientRect().bottom;
+
+		let scrollTo = scrollContainerTop;
+		if (top < stickyTop) {
+			scrollTo += top - stickyTop;
+		} else if (bottom > window.innerHeight - stickyBottom) {
+			scrollTo += bottom - window.innerHeight + stickyBottom;
 		}
+		scrollContainer.scrollTo({ top: scrollTo, behavior: 'instant' });
+	}
+
+	if (document.activeElement !== element) {
+		element.focus({ preventScroll: true });
 	}
-}
+};
diff --git a/packages/frontend/src/scripts/get-dom-node-or-null.ts b/packages/frontend/src/scripts/get-dom-node-or-null.ts
new file mode 100644
index 0000000000..fbf54675fd
--- /dev/null
+++ b/packages/frontend/src/scripts/get-dom-node-or-null.ts
@@ -0,0 +1,19 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+export const getNodeOrNull = (input: unknown): Node | null => {
+	if (input instanceof Node) return input;
+	return null;
+};
+
+export const getElementOrNull = (input: unknown): Element | null => {
+	if (input instanceof Element) return input;
+	return null;
+};
+
+export const getHTMLElementOrNull = (input: unknown): HTMLElement | null => {
+	if (input instanceof HTMLElement) return input;
+	return null;
+};
diff --git a/packages/frontend/src/scripts/hotkey.ts b/packages/frontend/src/scripts/hotkey.ts
index fd79baa604..ff3cbe98ac 100644
--- a/packages/frontend/src/scripts/hotkey.ts
+++ b/packages/frontend/src/scripts/hotkey.ts
@@ -2,6 +2,7 @@
  * SPDX-FileCopyrightText: syuilo and misskey-project
  * SPDX-License-Identifier: AGPL-3.0-only
  */
+import { getHTMLElementOrNull } from "@/scripts/get-dom-node-or-null.js";
 
 //#region types
 export type Keymap = Record<string, CallbackFunction | CallbackObject>;
@@ -30,8 +31,8 @@ type Action = {
 //#region consts
 const KEY_ALIASES = {
 	'esc': 'Escape',
-	'enter': ['Enter', 'NumpadEnter'],
-	'space': [' ', 'Spacebar'],
+	'enter': 'Enter',
+	'space': ' ',
 	'up': 'ArrowUp',
 	'down': 'ArrowDown',
 	'left': 'ArrowLeft',
@@ -44,6 +45,10 @@ const MODIFIER_KEYS = ['ctrl', 'alt', 'shift'];
 const IGNORE_ELEMENTS = ['input', 'textarea'];
 //#endregion
 
+//#region store
+let latestHotkey: Pattern & { callback: CallbackFunction } | null = null;
+//#endregion
+
 //#region impl
 export const makeHotkey = (keymap: Keymap) => {
 	const actions = parseKeymap(keymap);
@@ -51,13 +56,14 @@ export const makeHotkey = (keymap: Keymap) => {
 		if ('pswp' in window && window.pswp != null) return;
 		if (document.activeElement != null) {
 			if (IGNORE_ELEMENTS.includes(document.activeElement.tagName.toLowerCase())) return;
-			if ((document.activeElement as HTMLElement).isContentEditable) return;
+			if (getHTMLElementOrNull(document.activeElement)?.isContentEditable) return;
 		}
-		for (const { patterns, callback, options } of actions) {
-			if (matchPatterns(ev, patterns, options)) {
+		for (const action of actions) {
+			if (matchPatterns(ev, action)) {
 				ev.preventDefault();
 				ev.stopPropagation();
-				callback(ev);
+				action.callback(ev);
+				storePattern(ev, action.callback);
 			}
 		}
 	};
@@ -102,10 +108,21 @@ const parseOptions = (rawCallback: Keymap[keyof Keymap]) => {
 	return { ...defaultOptions } as const satisfies Action['options'];
 };
 
-const matchPatterns = (ev: KeyboardEvent, patterns: Action['patterns'], options: Action['options']) => {
+const matchPatterns = (ev: KeyboardEvent, action: Action) => {
+	const { patterns, options, callback } = action;
 	if (ev.repeat && !options.allowRepeat) return false;
 	const key = ev.key.toLowerCase();
 	return patterns.some(({ which, ctrl, shift, alt }) => {
+		if (
+			latestHotkey != null &&
+			latestHotkey.which.includes(key) &&
+			latestHotkey.ctrl === ctrl &&
+			latestHotkey.alt === alt &&
+			latestHotkey.shift === shift &&
+			latestHotkey.callback === callback
+		) {
+			return false;
+		}
 		if (!which.includes(key)) return false;
 		if (ctrl !== (ev.ctrlKey || ev.metaKey)) return false;
 		if (alt !== ev.altKey) return false;
@@ -114,6 +131,26 @@ const matchPatterns = (ev: KeyboardEvent, patterns: Action['patterns'], options:
 	});
 };
 
+let lastHotKeyStoreTimer: number | null = null;
+
+const storePattern = (ev: KeyboardEvent, callback: CallbackFunction) => {
+	if (lastHotKeyStoreTimer != null) {
+		clearTimeout(lastHotKeyStoreTimer);
+	}
+
+	latestHotkey = {
+		which: [ev.key.toLowerCase()],
+		ctrl: ev.ctrlKey || ev.metaKey,
+		alt: ev.altKey,
+		shift: ev.shiftKey,
+		callback,
+	};
+
+	lastHotKeyStoreTimer = window.setTimeout(() => {
+		latestHotkey = null;
+	}, 500);
+};
+
 const parseKeyCode = (input?: string | null) => {
 	if (input == null) return [];
 	const raw = getValueByKey(KEY_ALIASES, input);
diff --git a/packages/frontend/src/scripts/scroll.ts b/packages/frontend/src/scripts/scroll.ts
index 8edb6fca05..f0274034b5 100644
--- a/packages/frontend/src/scripts/scroll.ts
+++ b/packages/frontend/src/scripts/scroll.ts
@@ -23,6 +23,14 @@ export function getStickyTop(el: HTMLElement, container: HTMLElement | null = nu
 	return getStickyTop(el.parentElement, container, newTop);
 }
 
+export function getStickyBottom(el: HTMLElement, container: HTMLElement | null = null, bottom = 0) {
+	if (!el.parentElement) return bottom;
+	const data = el.dataset.stickyContainerFooterHeight;
+	const newBottom = data ? Number(data) + bottom : bottom;
+	if (el === container) return newBottom;
+	return getStickyBottom(el.parentElement, container, newBottom);
+}
+
 export function getScrollPosition(el: HTMLElement | null): number {
 	const container = getScrollContainer(el);
 	return container == null ? window.scrollY : container.scrollTop;