misskey/packages/frontend/src/directives/adaptive-border.ts

/*
 * SPDX-FileCopyrightText: syuilo and misskey-project
 * SPDX-License-Identifier: AGPL-3.0-only
 */

import type { Directive } from 'vue';
import { getBgColor } from '@/utility/get-bg-color.js';
import { themeManager } from '@/theme.js';

const handlerMap = new WeakMap<HTMLElement, () => void>();

export const adaptiveBorderDirective = {
	mounted(src) {
		function calc() {
			const parentBg = getBgColor(src.parentElement) ?? 'transparent';

			const myBg = window.getComputedStyle(src).backgroundColor;

			if (parentBg === myBg) {
				src.style.borderColor = 'var(--MI_THEME-divider)';
			} else {
				src.style.borderColor = myBg;
			}
		}

		handlerMap.set(src, calc);

		calc();

		themeManager.on('themeChanged', calc);
	},

	unmounted(src) {
		themeManager.off('themeChanged', handlerMap.get(src));
	},
} as Directive<HTMLElement>;