using CefSharp;
using CefSharp.Handler;
using CefSharp.ResponseFilter;
using NaiBa.Util.Helper;
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Work._29Tools.CefTools
{

    public class BaseResourceRequestHandler : ResourceRequestHandler
    {
        public string UserAgent = string.Empty;
        public Func<object, string, string, IRequest, bool> BeforeResourceLoadEvent; // sender, requestUrl, postData, true(表示取消执行）
        public Action<object, string, string, string, IRequest> ResourceLoadCompleteEvent;  // sender, requestUrl, postData, responseData
        public Action<object, string, string, string> ResourceRedirectEvent;      // sender, requestUrl, postData, redirectUrl
        public string[] ResourceContentTypeRegister = new string[] { "application/json", "javascript", "application/x-www-form-urlencoded", "text/html", "text/plain", "text/event-stream" };

        public string GetCharSet(string charSet)
        {
            if (string.IsNullOrEmpty(charSet))
            {
                charSet = "UTF-8";
            }
            return charSet;
        }

        public string GetPostData(IRequest request)
        {
            string postData = string.Empty;
            if (request.PostData != null && request.PostData.Elements.Any())
            {
                for (int i = 0; i < request.PostData.Elements.Count; i++)
                {
                    try
                    {
                        string charset = GetCharSet(request.GetCharSet());
                        if (request.PostData.Elements[i].Type != PostDataElementType.Empty)
                            postData += request.PostData.Elements[i].GetBody(charset);
                    }
                    catch (Exception ex)
                    {
                        LogHelper.WriteWithTime(ex);
                    }
                }
            }
            return postData;
        }
    }

    public class CustomResourceRequestHandlerLocal : BaseResourceRequestHandler
    {
        private ConcurrentDictionary<ulong, MemoryStream> responseDict = new ConcurrentDictionary<ulong, MemoryStream>();

        protected override CefReturnValue OnBeforeResourceLoad(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, IRequestCallback callback)
        {
            Uri url;
            if (Uri.TryCreate(request.Url, UriKind.Absolute, out url) == false)
            {
                //If we're unable to parse the Uri then cancel the request
                // avoid throwing any exceptions here as we're being called by unmanaged code
                return CefReturnValue.Cancel;
            }

            if (!string.IsNullOrEmpty(UserAgent))
            {
                var headers = request.Headers;
                headers["User-Agent"] = UserAgent;
                request.Headers = headers;
            }

            //NOTE: If you do not wish to implement this method returning false is the default behaviour
            // We also suggest you explicitly Dispose of the callback as it wraps an unmanaged resource.
            //callback.Dispose();
            //return false;

            //NOTE: When executing the callback in an async fashion need to check to see if it's disposed
            if (!callback.IsDisposed)
            {
                using (callback)
                {
                    if (request.Method == "POST")
                    {
                        try
                        {
                            string postData = GetPostData(request);
                            bool? result = BeforeResourceLoadEvent?.Invoke(chromiumWebBrowser, request.Url, postData, request);
                        }
                        catch (Exception ex)
                        {
                            LogHelper.WriteWithTime(ex);
                        }
                    }
                }
            }
            return CefReturnValue.Continue;
        }

        protected override void OnResourceRedirect(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, IResponse response, ref string newUrl)
        {
            try
            {
                if (ResourceRedirectEvent != null)
                {
                    string postData = GetPostData(request);
                    ResourceRedirectEvent.Invoke(chromiumWebBrowser, request.Url, postData, newUrl);
                }
            }
            catch (Exception ex)
            {
                LogHelper.WriteWithTime(ex);
            }
        }

        protected override bool OnProtocolExecution(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request)
        {
            return request.Url.StartsWith("mailto");
        }

        protected override bool OnResourceResponse(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, IResponse response)
        {
            //NOTE: You cannot modify the response, only the request
            // You can now access the headers
            //var headers = response.Headers;

            return false;
        }

        protected override IResponseFilter GetResourceResponseFilter(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, IResponse response)
        {
            try
            {
                string contentType = response.Headers["Content-Type"];
                if (string.IsNullOrEmpty(contentType))
                {
                    return null;
                }

                if (ResourceContentTypeRegister.Contains(contentType) || ResourceContentTypeRegister.Where(p => contentType.Contains(p)).Any())
                {
                    if (ResourceLoadCompleteEvent != null)
                    {
                        MemoryStream memoryStream = new MemoryStream();
                        responseDict.TryAdd(request.Identifier, memoryStream);
                        return new StreamResponseFilter(memoryStream);
                    }
                }
            }
            catch (Exception ex)
            {
                LogHelper.WriteWithTime(ex);
            }
            return null;
        }

        protected override void OnResourceLoadComplete(IWebBrowser chromiumWebBrowser, IBrowser browser, IFrame frame, IRequest request, IResponse response, UrlRequestStatus status, long receivedContentLength)
        {
            try
            {
                if (responseDict.ContainsKey(request.Identifier))
                {
                    MemoryStream memoryStream = null;
                    responseDict.TryRemove(request.Identifier, out memoryStream);

                    if (memoryStream != null)
                    {
                        byte[] data = memoryStream.ToArray();

                        string charset = GetCharSet(response.Charset);
                        var responseData = Encoding.GetEncoding(charset).GetString(data);

                        string postData = GetPostData(request);
                        ResourceLoadCompleteEvent.Invoke(chromiumWebBrowser, request.Url, postData, responseData, request);
                    }
                }
            }
            catch (Exception ex)
            {
                LogHelper.WriteWithTime(ex);
            }
        }
    }
}