using CefSharp;
using CefSharp.WinForms;
using System;
using System.Diagnostics;
using System.Drawing;
using System.IO;
using System.Windows.Forms;
using System.Xml;
using TradeIdeas.Logging;

namespace TradeIdeas.TIProGUI
{
    public partial class ContactSupportForm : Form, ISaveLayout
    {

        private ChromiumWebBrowser _webBrowser;
        private ContactSupportJsInterops _contactSupportJsInterops = new ContactSupportJsInterops();

        public WindowIconCache WindowIconCache => new WindowIconCache("CONTACT_SUPPORT_FORM");

        public bool Pinned { get; set; } = false;

        public ContactSupportForm()
        {
            InitializeComponent();
           
            // Initialize the browser.
            InitializeChromium();
            Controls.Add(_webBrowser);
            LoadContactSupportTemplate();
        }

        /// <summary>
        /// Initialize the Chromium browser.
        /// </summary>
        private void InitializeChromium()
        {
            try
            {
                Debug.WriteLine("InitializeChromium called Contact Support");
                _webBrowser = BrowserManager.RequestChromiumWebBrowser("https://trade-ideas.com/");
                _webBrowser.Dock = DockStyle.Fill;
                _webBrowser.IsBrowserInitializedChanged += _webBrowser_IsBrowserInitializedChanged;
                _webBrowser.JavascriptObjectRepository.Settings.LegacyBindingEnabled = true; // Set to allow Javascript bridging.
                _webBrowser.JavascriptObjectRepository.Register("contactSupportObj", _contactSupportJsInterops, true, BindingOptions.DefaultBinder); // Javascript class.

                /* Execute a script right after the html template load
                 * 1. Initializes the beacon
                 * 2. Add event listeners to these beacon's actions: close, ready
                 *    Close for closing the Contact Support Window after the beacon's closure
                 *    Ready for applying css customizations to the beacon for UI adjustments
                 * 3. Open the beacon automatically */
                _webBrowser.ExecuteScriptAsyncWhenPageLoaded("!function(e,t,n){function a(){var e=t.getElementsByTagName(\"script\")[0],n=t.createElement(\"script\");n.type=\"text/javascript\",n.async=!0,n.src=\"https://beacon-v2.helpscout.net\",e.parentNode.insertBefore(n,e)}if(e.Beacon=n=function(t,n,a){e.Beacon.readyQueue.push({method:t,options:n,data:a})},n.readyQueue=[],\"complete\"===t.readyState)return a();e.attachEvent?e.attachEvent(\"onload\",a):e.addEventListener(\"load\",a,!1)}(window,document,window.Beacon||function(){});\r\n  Beacon('init', '008b82bf-3f85-4ec6-ab4b-21b71ed257aa');Beacon('on', 'close', () => contactSupportObj.closeBeacon());Beacon('on', 'ready', () => {document.querySelector('.hsds-beacon .bQymmx.is-mobile').style.inset = '0px 0px 0px'; document.querySelector('.hsds-beacon .bQymmx.is-mobile').style.height = '100%';});Beacon('open');\r\n");

                //Subscribe to the beacon's closing event in order to replicate that action over this parent window
                _contactSupportJsInterops.OnBeaconClosed += OnBeaconClosed;
            }
            catch (Exception e)
            {
                string debugView = e.ToString();
                TILogger.Error(e.Message, e);
            }
        }

        /// <summary>
        /// Set the chromium browser to load the beacon in mobile mode.
        /// This ensures a better responsive experience that fully adapts to the Contact Support
        /// window host.
        /// </summary>
        private void _webBrowser_IsBrowserInitializedChanged(object sender, EventArgs e)
        {
            if (_webBrowser.IsBrowserInitialized)
            {
                var client = _webBrowser.GetDevToolsClient();
                client.Emulation.SetUserAgentOverrideAsync("Mozilla/5.0 (Linux; Android 10; SM-G975F) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Mobile Safari/537.36");
            }
        }

        /// <summary>
        /// Load the html template for the Contact Support Beacon
        /// </summary>
        private void LoadContactSupportTemplate()
        {
            if (null != _webBrowser && !_webBrowser.IsDisposed)
            {
                string curDir = new Uri(Directory.GetCurrentDirectory()).ToString();
                _webBrowser.Load($"{curDir}/Resources/ContactSupportPage.html");
            }
        }

        /// <summary>
        /// Dispose the resources used by the Chromium Webbrowser before
        /// closing the Contact Support window.
        /// </summary>
        private void ContactSupport_FormClosing(object sender, FormClosingEventArgs e)
        {
            if (null != _webBrowser && _webBrowser.IsBrowserInitialized && !_webBrowser.IsDisposed)
            {
                // Catch exception: Browser is not yet initialized.
                try
                {
                    Hide();
                    _webBrowser.Stop();
                    SuspendLayout();
                    _webBrowser.IsBrowserInitializedChanged -= _webBrowser_IsBrowserInitializedChanged;
                    _contactSupportJsInterops.OnBeaconClosed -= OnBeaconClosed;
                    if (Controls.Contains(_webBrowser))
                        Controls.Remove(_webBrowser);
                    ResumeLayout(false);
                    BrowserManager.RequestBrowserDisposal(_webBrowser);
                }
                catch (Exception ex)
                {
                    string debugView = ex.ToString();
                    TILogger.Error(ex.Message, ex);
                }
            }
        }

        /// <summary>
        /// Close the Contact Support window when the beacon is closed
        /// </summary>
        private void OnBeaconClosed()
        {
            this.BeginInvokeIfRequired(delegate
            {
                Close();
            });
        }

        /* In order to declare this form as an unpinned window,
         * the ISaveLayout has to be inherited and the presence
         * of the SaveLayout method is mandatory */

        public void SaveLayout(XmlNode parent)
        {
            throw new NotImplementedException();
        }

        public delegate void ChartJavaScriptBridgeOnBeaconClosedHandler();
        public delegate void ChartJavaScriptBridgeOnBeaconReadyHandler();
        /// <summary>
        /// This class handles the calls from the html template and the beacon
        /// to the Contact Support windows form.
        /// </summary>
        public class ContactSupportJsInterops
        {
            public event ChartJavaScriptBridgeOnBeaconClosedHandler OnBeaconClosed;

            public void closeBeacon()
            {
                OnBeaconClosed?.Invoke();
            }
        }
    }
}