import {useCallback, useEffect, useState} from 'react';
import {Link} from 'react-router-dom';
import {useTranslation} from 'react-i18next';
import {Users} from 'lucide-react';
import {toast} from 'sonner';

import {Button} from '@/components/ui/button';
import {Card, CardContent, CardHeader, CardTitle} from '@/components/ui/card';
import {fetchFollows, removeFollow} from '../utils/follows.js';
import {profileHref} from '../utils/people.js';

export default function FollowsCard() {
    const {t} = useTranslation();
    const [follows, setFollows] = useState(null);
    const [failed, setFailed] = useState(false);

    const load = useCallback(async () => {
        const {ok, data} = await fetchFollows();
        setFailed(!ok);
        if (ok) setFollows(data);
    }, []);

    useEffect(() => {
        load();
    }, [load]);

    const end = async (id) => {
        const {ok, status} = await removeFollow(id);
        if (!ok && status !== 401) toast.error(t('FOLLOW.ERROR'));
        await load();
    };

    const link = (displayName) => (
        <Link to={profileHref(displayName)} className="min-w-0 truncate hover:text-primary hover:underline">{displayName}</Link>
    );

    return (
        <Card>
            <CardHeader>
                <CardTitle className="flex items-center gap-2"><Users className="size-4 text-primary"/>{t('FOLLOW.TITLE')}</CardTitle>
            </CardHeader>
            <CardContent className="space-y-6">
                {failed && <p className="text-sm text-destructive">{t('FOLLOW.LOAD_ERROR')}</p>}
                {follows && (
                    <>
                        <section className="space-y-2">
                            <h3 className="text-sm font-medium">{t('FOLLOW.FOLLOWING')}</h3>
                            {follows.following.length === 0 && <p className="text-sm text-muted-foreground">{t('FOLLOW.NO_FOLLOWING')}</p>}
                            <ul className="space-y-1">
                                {follows.following.map((entry) => (
                                    <li key={entry.id} className="flex items-center justify-between gap-2 text-sm">
                                        {link(entry.displayName)}
                                        <Button variant="outline" size="sm" onClick={() => end(entry.id)}>{t('FOLLOW.UNFOLLOW')}</Button>
                                    </li>
                                ))}
                            </ul>
                        </section>
                        <section className="space-y-2">
                            <h3 className="text-sm font-medium">{t('FOLLOW.FOLLOWERS')}</h3>
                            {follows.followers.length === 0 && <p className="text-sm text-muted-foreground">{t('FOLLOW.NO_FOLLOWERS')}</p>}
                            <ul className="space-y-1">
                                {follows.followers.map((entry) => (
                                    <li key={entry.id} className="flex items-center justify-between gap-2 text-sm">
                                        {entry.displayName
                                            ? link(entry.displayName)
                                            : <span className="min-w-0 truncate text-muted-foreground">{t('FOLLOW.PRIVATE_USER')}</span>}
                                        <Button variant="outline" size="sm" onClick={() => end(entry.id)}>{t('FOLLOW.REMOVE')}</Button>
                                    </li>
                                ))}
                            </ul>
                        </section>
                    </>
                )}
            </CardContent>
        </Card>
    );
}