using System;
using System.IO;

namespace Microsoft.eShopWeb.PublicApi
{
    public static class ImageValidators
    {
        private const int ImageMaximumBytes = 512000;

        public static bool IsValidImage(this byte[] postedFile, string fileName)
        {
            return postedFile != null && postedFile.Length > 0 && postedFile.Length <= ImageMaximumBytes && IsExtensionValid(fileName);
        }

        private static bool IsExtensionValid(string fileName)
        {
            var extension = Path.GetExtension(fileName);

            return string.Equals(extension, ".jpg", StringComparison.OrdinalIgnoreCase) || 
                   string.Equals(extension, ".png", StringComparison.OrdinalIgnoreCase) || 
                   string.Equals(extension, ".gif", StringComparison.OrdinalIgnoreCase) || 
                   string.Equals(extension, ".jpeg", StringComparison.OrdinalIgnoreCase);
        }
    }
}