import { Metadata } from 'next';
import { db } from '@/lib/db';
import { auth } from '@/lib/auth';
import { redirect } from 'next/navigation';
import { getCachedTotalStorage } from '@/lib/admin-stats';
import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
import { Users, Folder, Video, MessageSquare, Mic, HardDrive, Image as ImageIcon } from 'lucide-react';

export const metadata: Metadata = {
    title: 'Admin Dashboard | OpenFrame',
    description: 'Admin overview dashboard',
};

function formatBytes(bytes: number, decimals = 2) {
    if (bytes < 0) return 'Error Fetching';
    if (!+bytes) return '0 Bytes';
    const k = 1024;
    const dm = decimals < 0 ? 0 : decimals;
    const sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
    const i = Math.floor(Math.log(bytes) / Math.log(k));
    return `${parseFloat((bytes / Math.pow(k, i)).toFixed(dm))} ${sizes[i]}`;
}

export default async function AdminDashboardPage() {
    const session = await auth();
    if (!session?.user?.isAdmin) {
        redirect('/');
    }

    // 1. Database Stats
    const [
        totalUsers,
        totalProjects,
        totalVideos,
        totalComments,
        totalVoiceComments,
        totalImageComments,
    ] = await Promise.all([
        db.user.count(),
        db.project.count(),
        db.video.count(),
        db.comment.count(),
        db.comment.count({
            where: { voiceUrl: { not: null } },
        }),
        db.comment.count({
            where: { imageUrl: { not: null } },
        }),
    ]);

    // 2. Storage Stats (Cached)
    const totalStorageBytes = await getCachedTotalStorage();

    return (
        <div className="flex-1 space-y-4 px-4 md:px-8">
            <div className="flex items-center justify-between space-y-2">
                <h2 className="text-3xl font-bold tracking-tight">Dashboard Overview</h2>
            </div>
            <div className="grid gap-4 md:grid-cols-2 lg:grid-cols-3">
                <Card>
                    <CardHeader className="flex flex-row items-center justify-between space-y-0 pb-2">
                        <CardTitle className="text-sm font-medium">Total Users</CardTitle>
                        <Users className="h-4 w-4 text-muted-foreground" />
                    </CardHeader>
                    <CardContent>
                        <div className="text-2xl font-bold">{totalUsers}</div>
                    </CardContent>
                </Card>
                <Card>
                    <CardHeader className="flex flex-row items-center justify-between space-y-0 pb-2">
                        <CardTitle className="text-sm font-medium">Workspaces & Projects</CardTitle>
                        <Folder className="h-4 w-4 text-muted-foreground" />
                    </CardHeader>
                    <CardContent>
                        <div className="text-2xl font-bold">{totalProjects}</div>
                        <p className="text-xs text-muted-foreground">
                            Total active projects on the platform
                        </p>
                    </CardContent>
                </Card>
                <Card>
                    <CardHeader className="flex flex-row items-center justify-between space-y-0 pb-2">
                        <CardTitle className="text-sm font-medium">Active Videos</CardTitle>
                        <Video className="h-4 w-4 text-muted-foreground" />
                    </CardHeader>
                    <CardContent>
                        <div className="text-2xl font-bold">{totalVideos}</div>
                    </CardContent>
                </Card>
                <Card>
                    <CardHeader className="flex flex-row items-center justify-between space-y-0 pb-2">
                        <CardTitle className="text-sm font-medium">Total Comments</CardTitle>
                        <MessageSquare className="h-4 w-4 text-muted-foreground" />
                    </CardHeader>
                    <CardContent>
                        <div className="text-2xl font-bold">{totalComments}</div>
                    </CardContent>
                </Card>
                <Card>
                    <CardHeader className="flex flex-row items-center justify-between space-y-0 pb-2">
                        <CardTitle className="text-sm font-medium">Voice Recordings</CardTitle>
                        <Mic className="h-4 w-4 text-muted-foreground" />
                    </CardHeader>
                    <CardContent>
                        <div className="text-2xl font-bold">{totalVoiceComments}</div>
                    </CardContent>
                </Card>
                <Card>
                    <CardHeader className="flex flex-row items-center justify-between space-y-0 pb-2">
                        <CardTitle className="text-sm font-medium">Image Attachments</CardTitle>
                        <ImageIcon className="h-4 w-4 text-muted-foreground" />
                    </CardHeader>
                    <CardContent>
                        <div className="text-2xl font-bold">{totalImageComments}</div>
                    </CardContent>
                </Card>
                <Card>
                    <CardHeader className="flex flex-row items-center justify-between space-y-0 pb-2">
                        <CardTitle className="text-sm font-medium">Cloudflare R2 Storage</CardTitle>
                        <HardDrive className="h-4 w-4 text-muted-foreground" />
                    </CardHeader>
                    <CardContent>
                        <div className="text-2xl font-bold">{formatBytes(totalStorageBytes)}</div>
                    </CardContent>
                </Card>
            </div>
        </div>
    );
}