import * as React from 'react';
import { useRef, useImperativeHandle, forwardRef, useEffect, useMemo, useContext, useCallback } from 'react';
import useViewIsReady from './hooks/useViewIsReady';
import useThemeCss from './hooks/useThemeCss';
import useContentSize from './hooks/useContentSize';
import useHtmlLoader from './hooks/useHtmlLoader';
import useWebviewToPluginMessages from './hooks/useWebviewToPluginMessages';
import useScriptLoader from './hooks/useScriptLoader';
import Logger from '@joplin/utils/Logger';
import { focus } from '@joplin/lib/utils/focusHandler';
import { WindowIdContext } from '../../gui/NewWindowOrIFrame';
import useSubmitHandler from './hooks/useSubmitHandler';
import useFormData from './hooks/useFormData';
import Setting from '@joplin/lib/models/Setting';
import getAssetPath from '../../utils/getAssetPath';
import { toForwardSlashes } from '@joplin/utils/path';

const logger = Logger.create('UserWebview');

export interface Props {
	html: string;
	scripts: string[];
	pluginId: string;
	viewId: string;
	themeId: number;
	minWidth?: number;
	minHeight?: number;
	fitToContent?: boolean;
	borderBottom?: boolean;
	theme?: Record<string, unknown>;
	onSubmit?: ()=> void;
	onDismiss?: ()=> void;
	onReady?: ()=> void;
}

export interface UserWebviewRef {
	formData: ()=> unknown;
	focus: ()=> void;
}

function UserWebview(props: Props, ref: React.Ref<UserWebviewRef>) {
	const minWidth = props.minWidth ? props.minWidth : 200;
	const minHeight = props.minHeight ? props.minHeight : 20;

	const viewRef = useRef<HTMLIFrameElement>(null);
	const isReady = useViewIsReady(viewRef);
	const cssFilePath = useThemeCss({ pluginId: props.pluginId, themeId: props.themeId });

	useEffect(() => {
		if (isReady && props.onReady) props.onReady();
		// eslint-disable-next-line @seiyab/react-hooks/exhaustive-deps -- Old code before rule was applied
	}, [isReady]);

	function frameWindow() {
		if (!viewRef.current) return null;
		return viewRef.current.contentWindow;
	}

	const postMessage = useCallback((name: string, args: unknown = null) => {
		const win = frameWindow();
		if (!win) return;

		logger.debug('Got message', name, args);

		win.postMessage({ target: 'webview', name, args }, '*');
	}, []);

	const { getFormData } = useFormData(viewRef, postMessage);

	useImperativeHandle(ref, () => {
		return {
			formData: function() {
				if (viewRef.current) {
					return getFormData();
				} else {
					return null;
				}
			},
			focus: function() {
				if (viewRef.current) focus('UserWebView::focus', viewRef.current);
			},
		};
	}, [getFormData]);

	const htmlHash = useHtmlLoader(
		viewRef,
		isReady,
		postMessage,
		props.html,
	);

	const contentSize = useContentSize(
		viewRef,
		htmlHash,
		minWidth,
		minHeight,
	);

	useSubmitHandler(
		viewRef,
		props.onSubmit,
		props.onDismiss,
	);

	const windowId = useContext(WindowIdContext);
	useWebviewToPluginMessages(
		viewRef,
		isReady,
		props.pluginId,
		props.viewId,
		windowId,
		postMessage,
	);

	useScriptLoader(
		postMessage,
		isReady,
		props.scripts,
		cssFilePath,
	);

	const style = useMemo(() => ({
		'--content-width': `${contentSize.width}px`,
		'--content-height': `${contentSize.height}px`,
	} as React.CSSProperties), [contentSize.width, contentSize.height]);

	const src = useMemo(() => {
		let isolate = Setting.value('featureFlag.plugins.isolatePluginWebViews');
		isolate ||= needsIsolation(props.pluginId);

		const path = toForwardSlashes(getAssetPath('services/plugins/UserWebviewIndex.html'));
		if (isolate) {
			return `joplin-content://plugin-webview/${path}`;
		} else {
			return `file://${path}`;
		}
	}, [props.pluginId]);

	return <iframe
		id={props.viewId}
		style={style}
		className={`plugin-user-webview ${props.fitToContent ? '-fit-to-content' : ''} ${props.borderBottom ? '-border-bottom' : ''}`}
		ref={viewRef}
		src={src}
	></iframe>;
}

export default forwardRef(UserWebview);

const needsIsolation = (pluginId: string) => {
	// Some plugins are broken unless isolated from the main application.
	// Always enable isolation for these plugins, even if disabled in settings:
	return ['joplin.plugin.note.tabs', 'joplin.plugin.benji.favorites', 'outline'].includes(pluginId);
};