import { HardDrive, Folder } from 'lucide-react';
import { useStorageUsage } from '@/hooks/useStorage';

/**
 * Props for the StorageUsageCard component.
 */
interface StorageUsageCardProps {
  /** Additional CSS classes to apply to the card container */
  className?: string;
}

function formatBytes(bytes: number): string {
  if (bytes < 1024) return `${bytes} B`;
  if (bytes < 1024 * 1024) return `${(bytes / 1024).toFixed(1)} KB`;
  if (bytes < 1024 * 1024 * 1024) return `${(bytes / (1024 * 1024)).toFixed(1)} MB`;
  return `${(bytes / (1024 * 1024 * 1024)).toFixed(1)} GB`;
}

/**
 * Displays storage usage statistics in a card format.
 * Shows total bytes used, usage percentage with color-coded progress bar,
 * file count, max file size, and breakdown by folder. Handles loading
 * and error states gracefully.
 *
 * @description Renders a card showing storage quota usage and file statistics.
 * @param props - The component props
 * @param props.className - Additional CSS classes for the card container
 *
 * @example
 * // Basic usage
 * <StorageUsageCard />
 *
 * @example
 * // With custom styling
 * <StorageUsageCard className="col-span-2 shadow-lg" />
 */
export function StorageUsageCard({ className = '' }: StorageUsageCardProps) {
  const { data, isLoading, error } = useStorageUsage();

  if (isLoading) {
    return (
      <div className={`bg-white rounded-lg border p-6 ${className}`}>
        <div className="animate-pulse">
          <div className="h-4 bg-gray-200 rounded w-1/3 mb-4" />
          <div className="h-8 bg-gray-200 rounded w-1/2 mb-4" />
          <div className="h-2 bg-gray-200 rounded w-full" />
        </div>
      </div>
    );
  }

  if (error || !data) {
    return (
      <div className={`bg-white rounded-lg border p-6 ${className}`}>
        <p className="text-gray-500">Unable to load storage usage</p>
      </div>
    );
  }

  const usedPercent = data.maxBytes ? data.usagePercent : 0;
  const progressColor =
    usedPercent > 90 ? 'bg-red-500' : usedPercent > 70 ? 'bg-yellow-500' : 'bg-blue-500';

  return (
    <div className={`bg-white rounded-lg border p-6 ${className}`}>
      <div className="flex items-center gap-3 mb-4">
        <div className="p-2 bg-blue-100 rounded-lg">
          <HardDrive className="w-5 h-5 text-blue-600" />
        </div>
        <h3 className="font-semibold text-gray-900">Storage Usage</h3>
      </div>

      {/* Usage stats */}
      <div className="space-y-4">
        <div>
          <div className="flex justify-between text-sm mb-1">
            <span className="text-gray-600">
              {formatBytes(data.totalBytes)} used
            </span>
            {data.maxBytes && (
              <span className="text-gray-500">
                of {formatBytes(data.maxBytes)}
              </span>
            )}
          </div>

          {data.maxBytes && (
            <div className="w-full bg-gray-200 rounded-full h-2">
              <div
                className={`${progressColor} h-2 rounded-full transition-all duration-300`}
                style={{ width: `${Math.min(usedPercent, 100)}%` }}
              />
            </div>
          )}
        </div>

        {/* Files count */}
        <div className="flex justify-between text-sm">
          <span className="text-gray-600">Total files</span>
          <span className="font-medium">{data.totalFiles.toLocaleString()}</span>
        </div>

        {/* Max file size */}
        {data.maxFileSize && (
          <div className="flex justify-between text-sm">
            <span className="text-gray-600">Max file size</span>
            <span className="font-medium">{formatBytes(data.maxFileSize)}</span>
          </div>
        )}

        {/* Files by folder */}
        {Object.keys(data.filesByFolder).length > 0 && (
          <div className="pt-4 border-t">
            <h4 className="text-sm font-medium text-gray-900 mb-2">By Folder</h4>
            <div className="space-y-2">
              {Object.entries(data.filesByFolder).map(([folder, count]) => (
                <div key={folder} className="flex items-center justify-between text-sm">
                  <div className="flex items-center gap-2 text-gray-600">
                    <Folder className="w-4 h-4" />
                    <span>{folder}</span>
                  </div>
                  <span className="font-medium">{count}</span>
                </div>
              ))}
            </div>
          </div>
        )}
      </div>
    </div>
  );
}