using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Xilium.CefGlue;

namespace Lskj.Control.BrowserSetting
{
    public class BsRequestHandler : CefRequestHandler
    {
        private readonly CefResourceRequestHandler externalProtocolResourceRequestHandler = new BsExternalProtocolResourceRequestHandler();

        protected override CefResourceRequestHandler GetResourceRequestHandler(CefBrowser browser, CefFrame frame, CefRequest request, bool isNavigation, bool isDownload, string requestInitiator, ref bool disableDefaultHandling)
        {
            if (BsExternalProtocolHandler.IsPrintProtocol(request.Url))
                return externalProtocolResourceRequestHandler;

            return null;
        }

        protected override bool OnBeforeBrowse(CefBrowser browser, CefFrame frame, CefRequest request, bool userGesture, bool isRedirect)
        {
            string url = request.Url;

            if (BsExternalProtocolHandler.IsPrintProtocol(url))
            {
                if (frame == null || frame.IsMain)
                {
                    BsExternalProtocolHandler.TryHandle(url);
                    return true;
                }

                return false;
            }

            return base.OnBeforeBrowse(browser, frame, request, userGesture, isRedirect);
        }

        protected override bool OnOpenUrlFromTab(CefBrowser browser, CefFrame frame, string targetUrl, CefWindowOpenDisposition targetDisposition, bool userGesture)
        {
            if (BsExternalProtocolHandler.TryHandle(targetUrl))
                return true;

            return base.OnOpenUrlFromTab(browser, frame, targetUrl, targetDisposition, userGesture);
        }

        protected override void OnRenderProcessTerminated(CefBrowser browser, CefTerminationStatus status)
        {
            browser.Reload();
        }
    }

    internal static class BsExternalProtocolHandler
    {
        private const string PrintProtocol = "lskjprint:";

        public static bool IsPrintProtocol(string url)
        {
            return !string.IsNullOrEmpty(url) && url.StartsWith(PrintProtocol, StringComparison.OrdinalIgnoreCase);
        }

        public static bool TryHandle(string url)
        {
            if (!IsPrintProtocol(url))
                return false;

            try
            {
                var processStartInfo = new System.Diagnostics.ProcessStartInfo(url)
                {
                    UseShellExecute = true
                };
                System.Diagnostics.Process.Start(processStartInfo);
            }
            catch (Exception ex)
            {
                System.Windows.Forms.MessageBox.Show(
                    "打开打印程序失败：" + ex.Message,
                    "提示",
                    System.Windows.Forms.MessageBoxButtons.OK,
                    System.Windows.Forms.MessageBoxIcon.Warning);
            }

            return true;
        }
    }

    internal sealed class BsExternalProtocolResourceRequestHandler : CefResourceRequestHandler
    {
        protected override CefCookieAccessFilter GetCookieAccessFilter(CefBrowser browser, CefFrame frame, CefRequest request)
        {
            return null;
        }

        protected override void OnProtocolExecution(CefBrowser browser, CefFrame frame, CefRequest request, ref bool allowOsExecution)
        {
            if (BsExternalProtocolHandler.IsPrintProtocol(request.Url))
            {
                allowOsExecution = true;
                return;
            }

            base.OnProtocolExecution(browser, frame, request, ref allowOsExecution);
        }
    }
}