adobe / spectrum-web-components / 16952396515

/**

 * Copyright 2025 Adobe. All rights reserved.

 * This file is licensed to you under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License. You may obtain a copy

 * of the License at http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software distributed under

 * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS

 * OF ANY KIND, either express or implied. See the License for the specific language

 * governing permissions and limitations under the License.

 */

import type { ReactiveController, ReactiveElement } from 'lit';

import { ProvideLang } from '@spectrum-web-components/theme';

export const languageResolverUpdatedSymbol = Symbol(

    'language resolver updated'

);

export class LanguageResolutionController implements ReactiveController {

    private host: ReactiveElement;

    private unsubscribe?: () => void;

    constructor(host: ReactiveElement) {

        this.host = host;

        this.host.addController(this);

    }

    public hostConnected(): void {

        this.resolveLanguage();

    }

    public hostDisconnected(): void {

        this.unsubscribe?.();

    }

    private resolveLanguage(): void {

        try {

            Intl.DateTimeFormat.supportedLocalesOf([this.language]);

        const queryThemeEvent = new CustomEvent<ProvideLang>(

            'sp-language-context',

            {

                bubbles: true,

                composed: true,

                detail: {

                    callback: (lang: string, unsubscribe: () => void) => {

                        const previous = this.language;

                        this.language = lang;

                        this.unsubscribe = unsubscribe;

                        this.host.requestUpdate(

                            languageResolverUpdatedSymbol,

                            previous

                        );

                    },

                },

                cancelable: true,

            }

        );

        this.host.dispatchEvent(queryThemeEvent);

    }

}