text: /*---------------------------------------------------------------------------------------------
   *  Copyright (c) Microsoft Corporation. All rights reserved.
   *  Licensed under the MIT License. See License.txt in the project root for license information.
   *--------------------------------------------------------------------------------------------*/
  // @ts-check
  
  /**
   * @typedef {{
   *   postMessage: (channel: string, data?: any) => void,
   *   onMessage: (channel: string, handler: any) => void,
   *   focusIframeOnCreate?: boolean,
   *   ready?: Promise<void>,
   *   onIframeLoaded?: (iframe: HTMLIFrameElement) => void,
   *   onElectron?: boolean,
   *   useParentPostMessage: boolean,
   * }} WebviewHost
   */
  
  const isSafari = navigator.vendor && navigator.vendor.indexOf('Apple') > -1 &&
  	navigator.userAgent &&
  	navigator.userAgent.indexOf('CriOS') === -1 &&
  	navigator.userAgent.indexOf('FxiOS') === -1;
  
  const searchParams = new URL(location.toString()).searchParams;
  const ID = searchParams.get('id');
  
  /**
   * Use polling to track focus of main webview and iframes within the webview
   *
   * @param {Object} handlers
   * @param {() => void} handlers.onFocus
   * @param {() => void} handlers.onBlur
   */
  const trackFocus = ({ onFocus, onBlur }) => {
  	const interval = 50;
  	let isFocused = document.hasFocus();
  	setInterval(() => {
  		const isCurrentlyFocused = document.hasFocus();
  		if (isCurrentlyFocused === isFocused) {
  			return;
  		}
  		isFocused = isCurrentlyFocused;
  		if (isCurrentlyFocused) {
  			onFocus();
  		} else {
  			onBlur();
  		}
  	}, interval);
  };
  
  const getActiveFrame = () => {
  	return /** @type {HTMLIFrameElement} */ (document.getElementById('active-frame'));
  };
  
  const getPendingFrame = () => {
  	return /** @type {HTMLIFrameElement} */ (document.getElementById('pending-frame'));
  };
  
  const vscodePostMessageFuncName = '__vscode_post_message__';
  
  const defaultStyles = document.createElement('style');
  defaultStyles.id = '_defaultStyles';
  defaultStyles.textContent = `
  	html {
  		scrollbar-color: var(--vscode-scrollbarSlider-background) var(--vscode-editor-background);
  	}
  
  	body {
  		background-color: transparent;
  		color: var(--vscode-editor-foreground);
  		font-family: var(--vscode-font-family);
  		font-weight: var(--vscode-font-weight);
  		font-size: var(--vscode-font-size);
  		margin: 0;
  		padding: 0 20px;
  	}
  
  	img {
  		max-width: 100%;
  		max-height: 100%;
  	}
  
  	a {
  		color: var(--vscode-textLink-foreground);
  	}
  
  	a:hover {
  		color: var(--vscode-textLink-activeForeground);
  	}
  
  	a:focus,
  	input:focus,
  	select:focus,
  	textarea:focus {
  		outline: 1px solid -webkit-focus-ring-color;
  		outline-offset: -1px;
  	}
  
  	code {
  		color: var(--vscode-textPreformat-foreground);
  	}
  
  	blockquote {
  		background: var(--vscode-textBlockQuote-background);
  		border-color: var(--vscode-textBlockQuote-border);
  	}
  
  	kbd {
  		color: var(--vscode-editor-foreground);
  		border-radius: 3px;
  		vertical-align: middle;
  		padding: 1px 3px;
  
  		background-color: hsla(0,0%,50%,.17);
  		border: 1px solid rgba(71,71,71,.4);
  		border-bottom-color: rgba(88,88,88,.4);
  		box-shadow: inset 0 -1px 0 rgba(88,88,88,.4);
  	}
  	.vscode-light kbd {
  		background-color: hsla(0,0%,87%,.5);
  		border: 1px solid hsla(0,0%,80%,.7);
  		border-bottom-color: hsla(0,0%,73%,.7);
  		box-shadow: inset 0 -1px 0 hsla(0,0%,73%,.7);
  	}
  
  	::-webkit-scrollbar {
  		width: 10px;
  		height: 10px;
  	}
  
  	::-webkit-scrollbar-corner {
  		background-color: var(--vscode-editor-background);
  	}
  
  	::-webkit-scrollbar-thumb {
  		background-color: var(--vscode-scrollbarSlider-background);
  	}
  	::-webkit-scrollbar-thumb:hover {
  		background-color: var(--vscode-scrollbarSlider-hoverBackground);
  	}
  	::-webkit-scrollbar-thumb:active {
  		background-color: var(--vscode-scrollbarSlider-activeBackground);
  	}`;
  
  /**
   * @param {boolean} allowMultipleAPIAcquire
   * @param {boolean} useParentPostMessage
   * @param {*} [state]
   * @return {string}
   */
  function getVsCodeApiScript(allowMultipleAPIAcquire, useParentPostMessage, state) {
  	const encodedState = state ? encodeURIComponent(state) : undefined;
  	return /* js */`
  			globalThis.acquireVsCodeApi = (function() {
  				const originalPostMessage = window.parent['${useParentPostMessage ? 'postMessage' : vscodePostMessageFuncName}'].bind(window.parent);
  				const doPostMessage = (channel, data, transfer) => {
  					${useParentPostMessage
  			? `originalPostMessage({ command: channel, data: data }, '*', transfer);`
  			: `originalPostMessage(channel, data, transfer);`
  		}
  				};
  
  				let acquired = false;
  
  				let state = ${state ? `JSON.parse(decodeURIComponent("${encodedState}"))` : undefined};
  
  				return () => {
  					if (acquired && !${allowMultipleAPIAcquire}) {
  						throw new Error('An instance of the VS Code API has already been acquired');
  					}
  					acquired = true;
  					return Object.freeze({
  						postMessage: function(message, transfer) {
  							doPostMessage('onmessage', { message, transfer }, transfer);
  						},
  						setState: function(newState) {
  							state = newState;
  							doPostMessage('do-update-state', JSON.stringify(newState));
  							return newState;
  						},
  						getState: function() {
  							return state;
  						}
  					});
  				};
  			})();
  			delete window.parent;
  			delete window.top;
  			delete window.frameElement;
  		`;
  }
  
  /** @type {Promise<void>} */
  const workerReady = new Promise(async (resolve, reject) => {
  	if (!areServiceWorkersEnabled()) {
  		return reject(new Error('Service Workers are not enabled in browser. Webviews will not work.'));
  	}
  
  	const expectedWorkerVersion = 1;
  
  	navigator.serviceWorker.register(`service-worker.js${self.location.search}`).then(
  		async registration => {
  			await navigator.serviceWorker.ready;
  
  			const versionHandler = (event) => {
  				if (event.data.channel !== 'version') {
  					return;
  				}
  
  				navigator.serviceWorker.removeEventListener('message', versionHandler);
  				if (event.data.version === expectedWorkerVersion) {
  					return resolve();
  				} else {
  					// If we have the wrong version, try once to unregister and re-register
  					return registration.update()
  						.then(() => navigator.serviceWorker.ready)
  						.finally(resolve);
  				}
  			};
  			navigator.serviceWorker.addEventListener('message', versionHandler);
  			registration.active.postMessage({ channel: 'version' });
  		},
  		error => {
  			reject(new Error(`Could not register service workers: ${error}.`));
  		});
  });
  
  /**
   * @param {WebviewHost} host
   */
  export async function createWebviewManager(host) {
  	// state
  	let firstLoad = true;
  	let loadTimeout;
  	let styleVersion = 0;
  
  	/** @type {Array<{ readonly message: any, transfer?: ArrayBuffer[] }>} */
  	let pendingMessages = [];
  
  	const initData = {
  		/** @type {number | undefined} */
  		initialScrollProgress: undefined,
  
  		/** @type {{ [key: string]: string }} */
  		styles: undefined,
  
  		/** @type {string | undefined} */
  		activeTheme: undefined,
  
  		/** @type {string | undefined} */
  		themeName: undefined,
  	};
  
  	host.onMessage('did-load-resource', (_event, data) => {
  		navigator.serviceWorker.ready.then(registration => {
  			registration.active.postMessage({ channel: 'did-load-resource', data }, data.data?.buffer ? [data.data.buffer] : []);
  		});
  	});
  
  	host.onMessage('did-load-localhost', (_event, data) => {
  		navigator.serviceWorker.ready.then(registration => {
  			registration.active.postMessage({ channel: 'did-load-localhost', data });
  		});
  	});
  
  	navigator.serviceWorker.addEventListener('message', event => {
  		switch (event.data.channel) {
  			case 'load-resource':
  			case 'load-localhost':
  				host.postMessage(event.data.channel, event.data);
  				return;
  		}
  	});
  	/**
  	 * @param {HTMLDocument?} document
  	 * @param {HTMLElement?} body
  	 */
  	const applyStyles = (document, body) => {
  		if (!document) {
  			return;
  		}
  
  		if (body) {
  			body.classList.remove('vscode-light', 'vscode-dark', 'vscode-high-contrast');
  			body.classList.add(initData.activeTheme);
  
  			body.dataset.vscodeThemeKind = initData.activeTheme;
  			body.dataset.vscodeThemeName = initData.themeName || '';
  		}
  
  		if (initData.styles) {
  			const documentStyle = document.documentElement.style;
  
  			// Remove stale properties
  			for (let i = documentStyle.length - 1; i >= 0; i--) {
  				const property = documentStyle[i];
  
  				// Don't remove properties that the webview might have added separately
  				if (property && property.startsWith('--vscode-')) {
  					documentStyle.removeProperty(property);
  				}
  			}
  
  			// Re-add new properties
  			for (const variable of Object.keys(initData.styles)) {
  				documentStyle.setProperty(`--${variable}`, initData.styles[variable]);
  			}
  		}
  	};
  
  	/**
  	 * @param {MouseEvent} event
  	 */
  	const handleInnerClick = (event) => {
  		if (!event || !event.view || !event.view.document) {
  			return;
  		}
  
  		const baseElement = event.view.document.getElementsByTagName('base')[0];
  
  		for (const pathElement of event.composedPath()) {
  			/** @type {any} */
  			const node = pathElement;
  			if (node.tagName && node.tagName.toLowerCase() === 'a' && node.href) {
  				if (node.getAttribute('href') === '#') {
  					event.view.scrollTo(0, 0);
  				} else if (node.hash && (node.getAttribute('href') === node.hash || (baseElement && node.href.indexOf(baseElement.href) >= 0))) {
  					let scrollTarget = event.view.document.getElementById(node.hash.substr(1, node.hash.length - 1));
  					if (scrollTarget) {
  						scrollTarget.scrollIntoView();
  					}
  				} else {
  					host.postMessage('did-click-link', node.href.baseVal || node.href);
  				}
  				event.preventDefault();
  				return;
  			}
  		}
  	};
  
  	/**
  	 * @param {MouseEvent} event
  	 */
  	const handleAuxClick =
  		(event) => {
  			// Prevent middle clicks opening a broken link in the browser
  			if (!event.view || !event.view.document) {
  				return;
  			}
  
  			if (event.button === 1) {
  				for (const pathElement of event.composedPath()) {
  					/** @type {any} */
  					const node = pathElement;
  					if (node.tagName && node.tagName.toLowerCase() === 'a' && node.href) {
  						event.preventDefault();
  						return;
  					}
  				}
  			}
  		};
  
  	/**
  	 * @param {KeyboardEvent} e
  	 */
  	const handleInnerKeydown = (e) => {
  		// If the keypress would trigger a browser event, such as copy or paste,
  		// make sure we block the browser from dispatching it. Instead VS Code
  		// handles these events and will dispatch a copy/paste back to the webview
  		// if needed
  		if (isUndoRedo(e)) {
  			e.preventDefault();
  		} else if (isCopyPasteOrCut(e)) {
  			if (host.onElectron) {
  				e.preventDefault();
  			} else {
  				return; // let the browser handle this
  			}
  		}
  
  		host.postMessage('did-keydown', {
  			key: e.key,
  			keyCode: e.keyCode,
  			code: e.code,
  			shiftKey: e.shiftKey,
  			altKey: e.altKey,
  			ctrlKey: e.ctrlKey,
  			metaKey: e.metaKey,
  			repeat: e.repeat
  		});
  	};
  	/**
  	 * @param {KeyboardEvent} e
  	 */
  	const handleInnerUp = (e) => {
  		host.postMessage('did-keyup', {
  			key: e.key,
  			keyCode: e.keyCode,
  			code: e.code,
  			shiftKey: e.shiftKey,
  			altKey: e.altKey,
  			ctrlKey: e.ctrlKey,
  			metaKey: e.metaKey,
  			repeat: e.repeat
  		});
  	};
  
  	/**
  	 * @param {KeyboardEvent} e
  	 * @return {boolean}
  	 */
  	function isCopyPasteOrCut(e) {
  		const hasMeta = e.ctrlKey || e.metaKey;
  		const shiftInsert = e.shiftKey && e.key.toLowerCase() === 'insert';
  		return (hasMeta && ['c', 'v', 'x'].includes(e.key.toLowerCase())) || shiftInsert;
  	}
  
  	/**
  	 * @param {KeyboardEvent} e
  	 * @return {boolean}
  	 */
  	function isUndoRedo(e) {
  		const hasMeta = e.ctrlKey || e.metaKey;
  		return hasMeta && ['z', 'y'].includes(e.key.toLowerCase());
  	}
  
  	let isHandlingScroll = false;
  
  	const handleWheel = (event) => {
  		if (isHandlingScroll) {
  			return;
  		}
  
  		host.postMessage('did-scroll-wheel', {
  			deltaMode: event.deltaMode,
  			deltaX: event.deltaX,
  			deltaY: event.deltaY,
  			deltaZ: event.deltaZ,
  			detail: event.detail,
  			type: event.type
  		});
  	};
  
  	const handleInnerScroll = (event) => {
  		if (!event.target || !event.target.body) {
  			return;
  		}
  		if (isHandlingScroll) {
  			return;
  		}
  
  		const progress = event.currentTarget.scrollY / event.target.body.clientHeight;
  		if (isNaN(progress)) {
  			return;
  		}
  
  		isHandlingScroll = true;
  		window.requestAnimationFrame(() => {
  			try {
  				host.postMessage('did-scroll', progress);
  			} catch (e) {
  				// noop
  			}
  			isHandlingScroll = false;
  		});
  	};
  
  	/**
  	 * @return {string}
  	 */
  	function toContentHtml(data) {
  		const options = data.options;
  		const text = data.contents;
  		const newDocument = new DOMParser().parseFromString(text, 'text/html');
  
  		newDocument.querySelectorAll('a').forEach(a => {
  			if (!a.title) {
  				a.title = a.getAttribute('href');
  			}
  		});
  
  		// Inject default script
  		if (options.allowScripts) {
  			const defaultScript = newDocument.createElement('script');
  			defaultScript.id = '_vscodeApiScript';
  			defaultScript.textContent = getVsCodeApiScript(options.allowMultipleAPIAcquire, host.useParentPostMessage, data.state);
  			newDocument.head.prepend(defaultScript);
  		}
  
  		// Inject default styles
  		newDocument.head.prepend(defaultStyles.cloneNode(true));
  
  		applyStyles(newDocument, newDocument.body);
  
  		// Check for CSP
  		const csp = newDocument.querySelector('meta[http-equiv="Content-Security-Policy"]');
  		if (!csp) {
  			host.postMessage('no-csp-found');
  		} else {
  			try {
  				// Attempt to rewrite CSPs that hardcode old-style resource endpoint
  				const endpointUrl = new URL(data.resourceEndpoint);
  				const newCsp = csp.getAttribute('content').replace(/(vscode-webview-resource|vscode-resource):(?=(\s|;|$))/g, endpointUrl.origin);
  				csp.setAttribute('content', newCsp);
  			} catch (e) {
  				console.error(`Could not rewrite csp: ${e}`);
  			}
  		}
  
  		// set DOCTYPE for newDocument explicitly as DOMParser.parseFromString strips it off
  		// and DOCTYPE is needed in the iframe to ensure that the user agent stylesheet is correctly overridden
  		return '<!DOCTYPE html>\n' + newDocument.documentElement.outerHTML;
  	}
  
  	onDomReady(() => {
  		if (!document.body) {
  			return;
  		}
  
  		host.onMessage('styles', (_event, data) => {
  			++styleVersion;
  
  			initData.styles = data.styles;
  			initData.activeTheme = data.activeTheme;
  			initData.themeName = data.themeName;
  
  			const target = getActiveFrame();
  			if (!target) {
  				return;
  			}
  
  			if (target.contentDocument) {
  				applyStyles(target.contentDocument, target.contentDocument.body);
  			}
  		});
  
  		// propagate focus
  		host.onMessage('focus', () => {
  			const activeFrame = getActiveFrame();
  			if (!activeFrame || !activeFrame.contentWindow) {
  				// Focus the top level webview instead
  				window.focus();
  				return;
  			}
  
  			if (document.activeElement === activeFrame) {
  				// We are already focused on the iframe (or one of its children) so no need
  				// to refocus.
  				return;
  			}
  
  			activeFrame.contentWindow.focus();
  		});
  
  		// update iframe-contents
  		let updateId = 0;
  		host.onMessage('content', async (_event, data) => {
  			const currentUpdateId = ++updateId;
  
  			try {
  				await workerReady;
  			} catch (e) {
  				console.error(`Webview fatal error: ${e}`);
  				host.postMessage('fatal-error', { message: e + '' });
  				return;
  			}
  
  			if (currentUpdateId !== updateId) {
  				return;
  			}
  
  			const options = data.options;
  			const newDocument = toContentHtml(data);
  
  			const initialStyleVersion = styleVersion;
  
  			const frame = getActiveFrame();
  			const wasFirstLoad = firstLoad;
  			// keep current scrollY around and use later
  			let setInitialScrollPosition;
  			if (firstLoad) {
  				firstLoad = false;
  				setInitialScrollPosition = (body, window) => {
  					if (!isNaN(initData.initialScrollProgress)) {
  						if (window.scrollY === 0) {
  							window.scroll(0, body.clientHeight * initData.initialScrollProgress);
  						}
  					}
  				};
  			} else {
  				const scrollY = frame && frame.contentDocument && frame.contentDocument.body ? frame.contentWindow.scrollY : 0;
  				setInitialScrollPosition = (body, window) => {
  					if (window.scrollY === 0) {
  						window.scroll(0, scrollY);
  					}
  				};
  			}
  
  			// Clean up old pending frames and set current one as new one
  			const previousPendingFrame = getPendingFrame();
  			if (previousPendingFrame) {
  				previousPendingFrame.setAttribute('id', '');
  				document.body.removeChild(previousPendingFrame);
  			}
  			if (!wasFirstLoad) {
  				pendingMessages = [];
  			}
  
  			const newFrame = document.createElement('iframe');
  			newFrame.setAttribute('id', 'pending-frame');
  			newFrame.setAttribute('frameborder', '0');
  			newFrame.setAttribute('sandbox', options.allowScripts ? 'allow-scripts allow-forms allow-same-origin allow-pointer-lock allow-downloads' : 'allow-same-origin allow-pointer-lock');
  			newFrame.setAttribute('allow', options.allowScripts ? 'clipboard-read; clipboard-write;' : '');
  			// We should just be able to use srcdoc, but I wasn't
  			// seeing the service worker applying properly.
  			// Fake load an empty on the correct origin and then write real html
  			// into it to get around this.
  			newFrame.src = `./fake.html?id=${ID}`;
  
  			newFrame.style.cssText = 'display: block; margin: 0; overflow: hidden; position: absolute; width: 100%; height: 100%; visibility: hidden';
  			document.body.appendChild(newFrame);
  
  			/**
  			 * @param {Document} contentDocument
  			 */
  			function onFrameLoaded(contentDocument) {
  				// Workaround for https://bugs.chromium.org/p/chromium/issues/detail?id=978325
  				setTimeout(() => {
  					contentDocument.open();
  					contentDocument.write(newDocument);
  					contentDocument.close();
  					hookupOnLoadHandlers(newFrame);
  
  					if (initialStyleVersion !== styleVersion) {
  						applyStyles(contentDocument, contentDocument.body);
  					}
  				}, 0);
  			}
  
  			if (!options.allowScripts && isSafari) {
  				// On Safari for iframes with scripts disabled, the `DOMContentLoaded` never seems to be fired.
  				// Use polling instead.
  				const interval = setInterval(() => {
  					// If the frame is no longer mounted, loading has stopped
  					if (!newFrame.parentElement) {
  						clearInterval(interval);
  						return;
  					}
  
  					if (newFrame.contentDocument.readyState !== 'loading') {
  						clearInterval(interval);
  						onFrameLoaded(newFrame.contentDocument);
  					}
  				}, 10);
  			} else {
  				newFrame.contentWindow.addEventListener('DOMContentLoaded', e => {
  					const contentDocument = e.target ? (/** @type {HTMLDocument} */ (e.target)) : undefined;
  					onFrameLoaded(contentDocument);
  				});
  			}
  
  			/**
  			 * @param {Document} contentDocument
  			 * @param {Window} contentWindow
  			 */
  			const onLoad = (contentDocument, contentWindow) => {
  				if (contentDocument && contentDocument.body) {
  					// Workaround for https://github.com/microsoft/vscode/issues/12865
  					// check new scrollY and reset if necessary
  					setInitialScrollPosition(contentDocument.body, contentWindow);
  				}
  
  				const newFrame = getPendingFrame();
  				if (newFrame && newFrame.contentDocument && newFrame.contentDocument === contentDocument) {
  					const oldActiveFrame = getActiveFrame();
  					if (oldActiveFrame) {
  						document.body.removeChild(oldActiveFrame);
  					}
  					// Styles may have changed since we created the element. Make sure we re-style
  					if (initialStyleVersion !== styleVersion) {
  						applyStyles(newFrame.contentDocument, newFrame.contentDocument.body);
  					}
  					newFrame.setAttribute('id', 'active-frame');
  					newFrame.style.visibility = 'visible';
  					if (host.focusIframeOnCreate) {
  						newFrame.contentWindow.focus();
  					}
  
  					contentWindow.addEventListener('scroll', handleInnerScroll);
  					contentWindow.addEventListener('wheel', handleWheel);
  
  					if (document.hasFocus()) {
  						contentWindow.focus();
  					}
  
  					pendingMessages.forEach((message) => {
  						contentWindow.postMessage(message.message, '*', message.transfer);
  					});
  					pendingMessages = [];
  				}
  
  				host.postMessage('did-load');
  			};
  
  			/**
  			 * @param {HTMLIFrameElement} newFrame
  			 */
  			function hookupOnLoadHandlers(newFrame) {
  				clearTimeout(loadTimeout);
  				loadTimeout = undefined;
  				loadTimeout = setTimeout(() => {
  					clearTimeout(loadTimeout);
  					loadTimeout = undefined;
  					onLoad(newFrame.contentDocument, newFrame.contentWindow);
  				}, 200);
  
  				newFrame.contentWindow.addEventListener('load', function (e) {
  					const contentDocument = /** @type {Document} */ (e.target);
  
  					if (loadTimeout) {
  						clearTimeout(loadTimeout);
  						loadTimeout = undefined;
  						onLoad(contentDocument, this);
  					}
  				});
  
  				// Bubble out various events
  				newFrame.contentWindow.addEventListener('click', handleInnerClick);
  				newFrame.contentWindow.addEventListener('auxclick', handleAuxClick);
  				newFrame.contentWindow.addEventListener('keydown', handleInnerKeydown);
  				newFrame.contentWindow.addEventListener('keyup', handleInnerUp);
  				newFrame.contentWindow.addEventListener('contextmenu', e => e.preventDefault());
  
  				if (host.onIframeLoaded) {
  					host.onIframeLoaded(newFrame);
  				}
  			}
  
  			host.postMessage('did-set-content', undefined);
  		});
  
  		// Forward message to the embedded iframe
  		host.onMessage('message', (_event, /** @type {{message: any, transfer?: ArrayBuffer[] }} */ data) => {
  			const pending = getPendingFrame();
  			if (!pending) {
  				const target = getActiveFrame();
  				if (target) {
  					target.contentWindow.postMessage(data.message, '*', data.transfer);
  					return;
  				}
  			}
  			pendingMessages.push(data);
  		});
  
  		host.onMessage('initial-scroll-position', (_event, progress) => {
  			initData.initialScrollProgress = progress;
  		});
  
  		host.onMessage('execCommand', (_event, data) => {
  			const target = getActiveFrame();
  			if (!target) {
  				return;
  			}
  			target.contentDocument.execCommand(data);
  		});
  
  		trackFocus({
  			onFocus: () => host.postMessage('did-focus'),
  			onBlur: () => host.postMessage('did-blur')
  		});
  
  		(/** @type {any} */ (window))[vscodePostMessageFuncName] = (command, data, transfer) => {
  			switch (command) {
  				case 'onmessage':
  				case 'do-update-state':
  					host.postMessage(command, data);
  					break;
  			}
  		};
  
  		// signal ready
  		host.postMessage('webview-ready', {});
  	});
  }
  
  /**
   * @param {() => void} callback
   */
  function onDomReady(callback) {
  	if (document.readyState === 'interactive' || document.readyState === 'complete') {
  		callback();
  	} else {
  		document.addEventListener('DOMContentLoaded', callback);
  	}
  }
  
  function areServiceWorkersEnabled() {
  	try {
  		return !!navigator.serviceWorker;
  	} catch (e) {
  		return false;
  	}
  }
  