using System.Collections.Specialized;
using System.Net;

namespace YLErp.Web
{
    /// <summary>
    /// 
    /// </summary>
    public static class WebExtensions
    {
        /// <summary>
        /// 是否本地请求
        /// </summary>
        public static bool IsLocal(this HttpRequest req)
        {
            var connection = req.HttpContext.Connection;
            if (connection.RemoteIpAddress != null)
            {
                if (connection.LocalIpAddress != null)
                {
                    return connection.RemoteIpAddress.Equals(connection.LocalIpAddress);
                }
                else
                {
                    return IPAddress.IsLoopback(connection.RemoteIpAddress);
                }
            }

            // for in memory TestServer or when dealing with default connection info
            return connection.RemoteIpAddress == null && connection.LocalIpAddress == null;
        }

        /// <summary>
        /// 
        /// </summary>
        public static string UrlLeftPart(this HttpRequest request)
        {
            return $"{request.Scheme}://{request.Host}";
        }

        /// <summary>
        /// IFormFile.SaveAs
        /// </summary>
        public static void SaveAs(this IFormFile file, string filePath)
        {
            Directory.CreateDirectory(Path.GetDirectoryName(filePath));

            using var stream = file.OpenReadStream();
            using var fstream = File.OpenWrite(filePath);
            stream.CopyTo(fstream);
        }

        /// <summary>
        /// IFormFile.ToUploadFileModel
        /// </summary>
        public static UploadFileModel ToUploadFileModel(this IFormFile file)
        {
            return new UploadFileModel
            {
                Length = file.Length,
                FileName = file.FileName,
                ContentType = file.ContentType,
                OpenReadStream = file.OpenReadStream
            };
        }

        /// <summary>
        /// IFormFileCollection.ToUploadFileModel
        /// </summary>
        public static List<UploadFileModel> ToUploadFileModelList(this IFormFileCollection files)
        {
            return files.Select(ToUploadFileModel).ToList();
        }

        /// <summary>
        /// IFormCollection.ToQueryString
        /// </summary>
        public static string ToQueryString(IFormCollection form, bool urlencoded = false)
        {
            var nv = new NameValueCollection();

            foreach (var key in form.Keys)
            {
                if (form.TryGetValue(key, out var values))
                {
                    foreach (var value in values)
                    {
                        nv.Add(key, value);
                    }
                }
            }

            return YieldChain.Helpers.UrlHelper.ToQueryString(nv, urlencoded);
        }
    }
}