using System.Net;
using System.Net.Http;
using System.Threading;
using System.Threading.Tasks;

namespace WcfControlMonitorWebLib
{
    /// <summary>
    /// 用于处理跨域问题
    /// </summary>
    internal class CorsHandler : DelegatingHandler
    {
        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
        {
            return base.SendAsync(request, cancellationToken)
                .ContinueWith((task) =>
                {
                    HttpResponseMessage response = task.Result;
                    response.Headers.Add("Access-Control-Allow-Credentials", "true");
                    response.Headers.Add("Access-Control-Allow-Headers", "Content-Type,Token");
                    response.Headers.Add("Access-Control-Allow-Methods", "*");
                    response.Headers.Add("Access-Control-Allow-Origin", "*");
                    if (request.Method == HttpMethod.Options)
                    {
                        response.StatusCode = HttpStatusCode.OK;
                    }
                    return response;
                });
        }
    }
}