using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;

namespace Step
{
    public class FormItem
    {
        public string ParameterName { get; set; }
        public byte[] Data { get; set; }
        public string FileName { get; set; }
        public string MediaType { get; set; }
        public string Value { get { return Encoding.Default.GetString(Data); } }
        public bool IsAFile { get { return !string.IsNullOrEmpty(FileName); } }
    }

    public static class MultipartHandler
    {
        public static async Task<List<FormItem>> ManageMultiPartFileAsync(HttpRequestMessage Request)
        {
            var provider = new MultipartMemoryStreamProvider();
            // Read multipart data
            await Request.Content.ReadAsMultipartAsync(provider);

            var formItems = new List<FormItem>();

            // Scan the Multiple Parts
            foreach (HttpContent contentPart in provider.Contents)
            {
                // Populate list with form-data parameters
                var formItem = new FormItem();
                var contentDisposition = contentPart.Headers.ContentDisposition;
                formItem.ParameterName = contentDisposition.Name.Trim('"');
                formItem.Data = await contentPart.ReadAsByteArrayAsync(); 
                formItem.FileName = String.IsNullOrEmpty(contentDisposition.FileName) ? "" : contentDisposition.FileName.Trim('"');
                formItem.MediaType = contentPart.Headers.ContentType == null ? "" : String.IsNullOrEmpty(contentPart.Headers.ContentType.MediaType) ? "" : contentPart.Headers.ContentType.MediaType;
                formItems.Add(formItem);
            }

            return formItems;
        }
    }
}