import * as React from 'react';
import {useEffect, useState} from 'react';
import Box from '@mui/material/Box';
import {ThemeProvider} from '@mui/material/styles';
import CssBaseline from '@mui/material/CssBaseline';
import Toolbar from '@mui/material/Toolbar';
import Notifications from "./Notifications";
import theme from "./theme";
import prefs from "../app/Prefs";
import connectionManager from "../app/ConnectionManager";
import Navigation from "./Navigation";
import ActionBar from "./ActionBar";
import notificationManager from "../app/NotificationManager";
import NoTopics from "./NoTopics";
import Preferences from "./Preferences";
import db from "../app/db";
import {useLiveQuery} from "dexie-react-hooks";
import poller from "../app/Poller";
import pruner from "../app/Pruner";

// TODO subscribe dialog:
//  - check/use existing user
//  - add baseUrl
// TODO embed into ntfy server
// TODO make default server functional
// TODO business logic with callbacks
// TODO connection indicator in subscription list
// TODO connectionmanager should react on users changes
// TODO attachments

const App = () => {
    console.log(`[App] Rendering main view`);

    const [mobileDrawerOpen, setMobileDrawerOpen] = useState(false);
    const [prefsOpen, setPrefsOpen] = useState(false);
    const [selectedSubscription, setSelectedSubscription] = useState(null);
    const [notificationsGranted, setNotificationsGranted] = useState(notificationManager.granted());
    const subscriptions = useLiveQuery(() => db.subscriptions.toArray());
    const users = useLiveQuery(() => db.users.toArray());
    const handleSubscriptionClick = async (subscriptionId) => {
        const subscription = await db.subscriptions.get(subscriptionId); // FIXME
        setSelectedSubscription(subscription);
        setPrefsOpen(false);
    }
    const handleSubscribeSubmit = async (subscription) => {
        console.log(`[App] New subscription: ${subscription.id}`, subscription);
        await db.subscriptions.put(subscription); // FIXME
        setSelectedSubscription(subscription);
        handleRequestPermission();
        try {
            await poller.poll(subscription);
        } catch (e) {
            console.error(`[App] Error polling newly added subscription ${subscription.id}`, e);
        }
    };
    const handleUnsubscribe = async (subscriptionId) => {
        console.log(`[App] Unsubscribing from ${subscriptionId}`);
        await db.subscriptions.delete(subscriptionId); // FIXME
        await db.notifications
            .where({subscriptionId: subscriptionId})
            .delete(); // FIXME
        const newSelected = await db.subscriptions.toCollection().first(); // FIXME May be undefined
        setSelectedSubscription(newSelected);
    };
    const handleRequestPermission = () => {
        notificationManager.maybeRequestPermission((granted) => {
            setNotificationsGranted(granted);
        })
    };
    const handlePrefsClick = () => {
        setPrefsOpen(true);
        setSelectedSubscription(null);
    };
    // Define hooks: Note that the order of the hooks is important. The "loading" hooks
    // must be before the "saving" hooks.
    useEffect(() => {
        poller.startWorker();
        pruner.startWorker();
        const load = async () => {
            const subs = await db.subscriptions.toArray(); // Cannot be 'subscriptions'
            const selectedSubscriptionId = await prefs.selectedSubscriptionId();

            // Set selected subscription
            const maybeSelectedSubscription = subs?.filter(s => s.id = selectedSubscriptionId);
            if (maybeSelectedSubscription.length > 0) {
                setSelectedSubscription(maybeSelectedSubscription[0]);
            }

        };
        setTimeout(() => load(), 5000);
    }, [/* initial render */]);
    useEffect(() => {
        const notificationClickFallback = (subscription) => setSelectedSubscription(subscription);
        const handleNotification = async (subscriptionId, notification) => {
            try {
                const subscription = await db.subscriptions.get(subscriptionId); // FIXME
                await db.notifications.add({ ...notification, subscriptionId }); // FIXME, will throw if exists!
                await db.subscriptions.update(subscriptionId, { last: notification.id });
                await notificationManager.notify(subscription, notification, notificationClickFallback)
            } catch (e) {
                console.error(`[App] Error handling notification`, e);
            }
        };
        connectionManager.refresh(subscriptions, users, handleNotification);
    }, [subscriptions, users]);
    useEffect(() => {
        const subscriptionId = (selectedSubscription) ? selectedSubscription.id : "";
        prefs.setSelectedSubscriptionId(subscriptionId)
    }, [selectedSubscription]);

    return (
        <ThemeProvider theme={theme}>
            <CssBaseline/>
            <Box sx={{display: 'flex'}}>
                <CssBaseline/>
                <ActionBar
                    selectedSubscription={selectedSubscription}
                    onUnsubscribe={handleUnsubscribe}
                    onMobileDrawerToggle={() => setMobileDrawerOpen(!mobileDrawerOpen)}
                />
                <Box component="nav" sx={{width: {sm: Navigation.width}, flexShrink: {sm: 0}}}>
                    <Navigation
                        subscriptions={subscriptions}
                        selectedSubscription={selectedSubscription}
                        mobileDrawerOpen={mobileDrawerOpen}
                        notificationsGranted={notificationsGranted}
                        prefsOpen={prefsOpen}
                        onMobileDrawerToggle={() => setMobileDrawerOpen(!mobileDrawerOpen)}
                        onSubscriptionClick={handleSubscriptionClick}
                        onSubscribeSubmit={handleSubscribeSubmit}
                        onPrefsClick={handlePrefsClick}
                        onRequestPermissionClick={handleRequestPermission}
                    />
                </Box>
                <Main>
                    <Toolbar/>
                    <Content
                        subscription={selectedSubscription}
                        prefsOpen={prefsOpen}
                    />
                </Main>
            </Box>
        </ThemeProvider>
    );
}

const Main = (props) => {
    return (
        <Box
            component="main"
            sx={{
                display: 'flex',
                flexGrow: 1,
                flexDirection: 'column',
                padding: 3,
                width: {sm: `calc(100% - ${Navigation.width}px)`},
                height: '100vh',
                overflow: 'auto',
                backgroundColor: (theme) => theme.palette.mode === 'light' ? theme.palette.grey[100] : theme.palette.grey[900]
            }}
        >
            {props.children}
        </Box>
    );
};

const Content = (props) => {
    if (props.prefsOpen) {
        return <Preferences/>;
    }
    if (props.subscription) {
        return <Notifications subscription={props.subscription}/>;
    }
    return <NoTopics/>;
};

export default App;