import Link from 'next/link';
import { Plus, Building2, Clock, FolderOpen, Users } from 'lucide-react';
import { Button } from '@/components/ui/button';
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
import { auth } from '@/lib/auth';
import { redirect } from 'next/navigation';
import { db } from '@/lib/db';

function formatRelativeTime(date: Date): string {
  const now = new Date();
  const diffMs = now.getTime() - date.getTime();
  const diffMins = Math.floor(diffMs / 60000);
  const diffHours = Math.floor(diffMs / 3600000);
  const diffDays = Math.floor(diffMs / 86400000);

  if (diffMins < 1) return 'just now';
  if (diffMins < 60) return `${diffMins}m ago`;
  if (diffHours < 24) return `${diffHours}h ago`;
  if (diffDays < 7) return `${diffDays}d ago`;
  return date.toLocaleDateString();
}

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

  const workspaces = await db.workspace.findMany({
    where: {
      OR: [
        { ownerId: session.user.id },
        { members: { some: { userId: session.user.id } } },
      ],
    },
    include: {
      owner: { select: { id: true, name: true } },
      _count: {
        select: {
          projects: true,
          members: true,
        },
      },
    },
    orderBy: { updatedAt: 'desc' },
  });

  return (
    <div className="px-6 lg:px-8 py-8 w-full">
      {/* Header */}
      <div className="flex items-center justify-between mb-8">
        <div>
          <h1 className="text-3xl font-bold tracking-tight">Workspaces</h1>
          <p className="text-muted-foreground mt-1">
            Manage your workspaces and their projects
          </p>
        </div>
        <Button asChild>
          <Link href="/workspaces/new">
            <Plus className="h-4 w-4 mr-2" />
            New Workspace
          </Link>
        </Button>
      </div>

      {/* Workspaces Grid */}
      {workspaces.length > 0 ? (
        <div className="grid gap-4 md:grid-cols-2 lg:grid-cols-3">
          {workspaces.map((workspace) => (
            <Link key={workspace.id} href={`/workspaces/${workspace.id}`}>
              <Card className="h-full transition-colors hover:bg-accent/50 cursor-pointer">
                <CardHeader>
                  <CardTitle className="flex items-center gap-2">
                    <Building2 className="h-5 w-5 text-primary" />
                    {workspace.name}
                  </CardTitle>
                  <CardDescription className="line-clamp-2">
                    {workspace.description || 'No description'}
                  </CardDescription>
                </CardHeader>
                <CardContent>
                  <div className="flex items-center gap-4 text-sm text-muted-foreground">
                    <span className="flex items-center gap-1">
                      <Clock className="h-3.5 w-3.5" />
                      {formatRelativeTime(workspace.updatedAt)}
                    </span>
                    <span className="flex items-center gap-1">
                      <FolderOpen className="h-3.5 w-3.5" />
                      {workspace._count.projects} projects
                    </span>
                    <span className="flex items-center gap-1">
                      <Users className="h-3.5 w-3.5" />
                      {workspace._count.members + 1}
                    </span>
                  </div>
                </CardContent>
              </Card>
            </Link>
          ))}
        </div>
      ) : (
        <Card className="border-dashed">
          <CardContent className="flex flex-col items-center justify-center py-16">
            <Building2 className="h-12 w-12 text-muted-foreground mb-4" />
            <h3 className="text-lg font-medium mb-2">No workspaces yet</h3>
            <p className="text-muted-foreground text-center mb-4">
              Create a workspace to organize your projects and invite team members
            </p>
            <Button asChild>
              <Link href="/workspaces/new">
                <Plus className="h-4 w-4 mr-2" />
                Create Workspace
              </Link>
            </Button>
          </CardContent>
        </Card>
      )}
    </div>
  );
}