/********************************************************************************
 * Copyright (C) 2019 TypeFox and others.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the Eclipse
 * Public License v. 2.0 are satisfied: GNU General Public License, version 2
 * with the GNU Classpath Exception which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 ********************************************************************************/

import { injectable, inject } from 'inversify';
import { ContextKeyService, ContextKey } from '@devpodio/core/lib/browser/context-key-service';

@injectable()
export class MonacoContextKeyService extends ContextKeyService {

    @inject(monaco.contextKeyService.ContextKeyService)
    protected readonly contextKeyService: monaco.contextKeyService.ContextKeyService;

    createKey<T>(key: string, defaultValue: T | undefined): ContextKey<T> {
        return this.contextKeyService.createKey(key, defaultValue);
    }

    activeContext?: HTMLElement;

    match(expression: string, context?: HTMLElement): boolean {
        const ctx = context || this.activeContext || (window.document.activeElement instanceof HTMLElement ? window.document.activeElement : undefined);
        const parsed = this.parse(expression);
        if (!ctx) {
            return this.contextKeyService.contextMatchesRules(parsed);
        }
        const keyContext = this.contextKeyService.getContext(ctx);
        return monaco.keybindings.KeybindingResolver.contextMatchesRules(keyContext, parsed);
    }

    protected readonly expressions = new Map<string, monaco.contextkey.ContextKeyExpr>();
    protected parse(when: string): monaco.contextkey.ContextKeyExpr {
        let expression = this.expressions.get(when);
        if (!expression) {
            expression = monaco.contextkey.ContextKeyExpr.deserialize(when);
            this.expressions.set(when, expression);
        }
        return expression;
    }

}