[html] embedded content documents updating, refactoring

extensions/html/client/src/embeddedContentDocuments.ts

@@ -0,0 +1,118 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+'use strict';
+
+import { workspace, Uri, EventEmitter, Disposable, TextDocument } from 'vscode';
+import { LanguageClient, RequestType } from 'vscode-languageclient';
+
+
+interface EmbeddedContentParams {
+	uri: string;
+	embeddedLanguageId: string;
+}
+
+interface EmbeddedContent {
+	content: string;
+	version: number;
+}
+
+namespace EmbeddedContentRequest {
+	export const type: RequestType<EmbeddedContentParams, EmbeddedContent, any> = { get method() { return 'embedded/content'; } };
+}
+
+export interface EmbeddedDocuments extends Disposable {
+	getVirtualDocumentUri: (parentDocumentUri: string, embeddedLanguageId: string) => Uri;
+	openVirtualDocument: (embeddedContentUri: Uri, expectedVersion: number) => Thenable<TextDocument>;
+}
+
+
+export function initializeEmbeddedContentDocuments(embeddedScheme: string, client: LanguageClient): EmbeddedDocuments {
+	let toDispose: Disposable[] = [];
+
+	let embeddedContentChanged = new EventEmitter<Uri>();
+
+	// remember all open virtual documents with the version of the content
+	let openVirtualDocuments: { [uri: string]: number } = {};
+
+	// documents are closed after a time out or when collected.
+	toDispose.push(workspace.onDidCloseTextDocument(d => {
+		if (d.uri.scheme === embeddedScheme) {
+			delete openVirtualDocuments[d.uri.toString()];
+		}
+	}));
+
+	// virtual document provider
+	toDispose.push(workspace.registerTextDocumentContentProvider(embeddedScheme, {
+		provideTextDocumentContent: uri => {
+			if (uri.scheme === embeddedScheme) {
+				let contentRequestParms = { uri: getParentDocumentUri(uri), embeddedLanguageId: getEmbeddedLanguageId(uri) };
+				return client.sendRequest(EmbeddedContentRequest.type, contentRequestParms).then(content => {
+					if (content) {
+						openVirtualDocuments[uri.toString()] = content.version;
+						return content.content;
+					} else {
+						delete openVirtualDocuments[uri.toString()];
+						return '';
+					}
+				});
+			}
+			return '';
+		},
+		onDidChange: embeddedContentChanged.event
+	}));
+
+	function getVirtualDocumentUri(parentDocumentUri: string, embeddedLanguageId: string) {
+		return Uri.parse(embeddedScheme + '://' + embeddedLanguageId + '/' + encodeURIComponent(parentDocumentUri) + '.' + embeddedLanguageId);
+	};
+
+	function getParentDocumentUri(virtualDocumentUri: Uri): string {
+		let languageId = virtualDocumentUri.authority;
+		let path = virtualDocumentUri.path.substring(1, virtualDocumentUri.path.length - languageId.length - 1); // remove leading '/' and new file extension
+		return decodeURIComponent(path);
+	};
+
+	function getEmbeddedLanguageId(virtualDocumentUri: Uri): string {
+		return virtualDocumentUri.authority;
+	}
+
+	function ensureContentUpdated(virtualURI: Uri, expectedVersion: number) {
+		let virtualURIString = virtualURI.toString();
+		let virtualDocVersion = openVirtualDocuments[virtualURIString];
+		if (isDefined(virtualDocVersion) && virtualDocVersion !== expectedVersion) {
+			return new Promise<void>((resolve, reject) => {
+				let subscription = workspace.onDidChangeTextDocument(d => {
+					if (d.document.uri.toString() === virtualURIString) {
+						subscription.dispose();
+						resolve();
+					}
+				});
+				embeddedContentChanged.fire(virtualURI);
+			});
+		}
+		return Promise.resolve();
+	};
+
+	function openVirtualDocument(virtualURI: Uri, expectedVersion: number): Thenable<TextDocument> {
+		return ensureContentUpdated(virtualURI, expectedVersion).then(_ => {
+			return workspace.openTextDocument(virtualURI).then(document => {
+				if (expectedVersion === openVirtualDocuments[virtualURI.toString()]) {
+					return document;
+				}
+				return void 0;
+			});
+		});
+	};
+
+	return {
+		getVirtualDocumentUri,
+		openVirtualDocument,
+		dispose: Disposable.from(...toDispose).dispose
+	};
+
+}
+
+function isDefined(o: any) {
+	return typeof o !== 'undefined';
+}