vscode/extensions/css-language-features/server/src/utils/documentContext.ts

/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

import { DocumentContext } from 'vscode-css-languageservice';
import { endsWith, startsWith } from '../utils/strings';
import { WorkspaceFolder } from 'vscode-languageserver';
import { Utils, URI } from 'vscode-uri';

export function getDocumentContext(documentUri: string, workspaceFolders: WorkspaceFolder[]): DocumentContext {
	function getRootFolder(): string | undefined {
		for (const folder of workspaceFolders) {
			let folderURI = folder.uri;
			if (!endsWith(folderURI, '/')) {
				folderURI = folderURI + '/';
			}
			if (startsWith(documentUri, folderURI)) {
				return folderURI;
			}
		}
		return undefined;
	}

	return {
		resolveReference: (ref: string, base = documentUri) => {
			if (ref[0] === '/') { // resolve absolute path against the current workspace folder
				const folderUri = getRootFolder();
				if (folderUri) {
					return folderUri + ref.substring(1);
				}
			}
			const baseUri = URI.parse(base);
			const baseUriDir = baseUri.path.endsWith('/') ? baseUri : Utils.dirname(baseUri);
			return Utils.resolvePath(baseUriDir, ref).toString(true);
		},
	};
}