using Android.Content;
using Android.Webkit;
using Microsoft.Maui.Controls;
using Microsoft.Maui.Handlers;
using Microsoft.Maui.Platform;
using System;
using System.Threading.Tasks;
using Android.Views;
using Xamarin.Forms.Clinical6.UI.Controls;

namespace MAUI.Clinical6.Platforms.Android.Renders
{
    public class LocalHtmlWebViewerHandler : ViewHandler<LocalHtmlWebViewer, global::Android.Webkit.WebView>
    {
        private ExtendedWebViewClient _webDelegate;

        public static IPropertyMapper<LocalHtmlWebViewer, LocalHtmlWebViewerHandler> Mapper =
            new PropertyMapper<LocalHtmlWebViewer, LocalHtmlWebViewerHandler>(ViewHandler.ViewMapper)
            {
                [nameof(LocalHtmlWebViewer.Html)] = MapHtml
            };

        public LocalHtmlWebViewerHandler() : base(Mapper)
        {
        }

        protected override global::Android.Webkit.WebView CreatePlatformView()
        {
            var webView = new global::Android.Webkit.WebView(Context);
            webView.Settings.JavaScriptEnabled = true;
            webView.LayoutParameters = new ViewGroup.LayoutParams(
                ViewGroup.LayoutParams.MatchParent,
                ViewGroup.LayoutParams.WrapContent
            );
            return webView;
        }

        protected override void ConnectHandler(global::Android.Webkit.WebView platformView)
        {
            base.ConnectHandler(platformView);
            LoadHtml();
        }

        private static void MapHtml(LocalHtmlWebViewerHandler handler, LocalHtmlWebViewer view)
        {
            handler?.LoadHtml();
        }

        private void LoadHtml()
        {
            if (VirtualView == null || PlatformView == null)
                return;

            if (string.IsNullOrWhiteSpace(VirtualView.Html))
            {
                VirtualView.IsVisible = false;
                return;
            }

            VirtualView.IsVisible = true;

            var htmlSource = new HtmlWebViewSource
            {
                Html = VirtualView.Html
            };
            VirtualView.Source = htmlSource;

            _webDelegate = new ExtendedWebViewClient(VirtualView);
            PlatformView.SetWebViewClient(_webDelegate);
            PlatformView.LoadDataWithBaseURL(null, VirtualView.Html, "text/html", "UTF-8", null);
        }
    }

    internal class ExtendedWebViewClient : WebViewClient
    {
        private readonly LocalHtmlWebViewer _control;
        private readonly double _mainDisplayHeight;

        public ExtendedWebViewClient(LocalHtmlWebViewer control)
        {
            _control = control;
            var mainDisplayInfo = DeviceDisplay.Current.MainDisplayInfo;
            _mainDisplayHeight = mainDisplayInfo.Height / mainDisplayInfo.Density;
        }

        public override async void OnPageFinished(global::Android.Webkit.WebView view, string url)
        {
            if (_control != null)
            {
                int i = 10;

                try
                {
                    while (view?.ContentHeight == 0 && i-- > 0)
                    {
                        await Task.Delay(100);
                    }
                }
                catch { }

                try
                {
                    var contentHeight = view.ContentHeight / view.Scale;

                    if (contentHeight > (_mainDisplayHeight - (_mainDisplayHeight * 0.25)))
                    {
                        if (contentHeight > (_mainDisplayHeight - (_mainDisplayHeight * 0.35)))
                        {
                            _control.HeightRequest = _mainDisplayHeight - (_mainDisplayHeight * 0.35);
                        }
                        else
                        {
                            _control.HeightRequest = _mainDisplayHeight - (_mainDisplayHeight * 0.25);
                        }
                    }
                    else
                    {
                        _control.HeightRequest = contentHeight;
                    }
                }
                catch (Exception ex)
                {
                    Console.WriteLine(ex);
                }
            }

            base.OnPageFinished(view, url);
        }
    }
}