using System;   
using System.Drawing;
using System.Windows.Forms;
using System.Drawing.Imaging;
using CefSharp;
using CefSharp.WinForms;
using CommandLine;
using System.Collections.Generic;
using System.IO;

namespace ScreenshotForm
{
    public partial class ScreenShotForm : Form
    {
        public ChromiumWebBrowser browser;
        private int variableNum = 1;
        private string path;
        private bool noClose = false;
        private Options _options = null;

        public class Options
        {
            [Option('u', "url", Required = false, Default = null, HelpText = "url to use")]
            public string Url { get; set; }
            [Option('o', "output", Required = true, HelpText = "Enter the Path and the output image name, please include the .PNG at the end")]
            public string Path { get; set; }
            [Option('w', "width", Required = false, Default = 800, HelpText = "width in pixels for browser area")]
            public int Width { get; set; }
            [Option('h', "height", Required = false, Default = 600, HelpText = "height in pixels for browser area")]
            public int Height { get; set; }
            [Option('c', "no-exit", Default = false, Required = false, HelpText = "no-exit means that the progrma will not exit after taking the initial screenshot")]
            public bool NoClose { get; set; }
  
            //For the Screenshot
            [Option('x', "screenshot-x", Required = false, Default = 0, HelpText = "width in pixels for browser area")]
            public int ScreenX { get; set; }
            [Option('y', "screenshot-y", Required = false, Default = 0, HelpText = "width in pixels for browser area")]
            public int ScreenY { get; set; }
            [Option('l', "screenshot-width", Required = false, Default = 0, HelpText = "width for the screenshot")]
            public int ScreenW { get; set; }
            [Option('t', "screenshot-height", Required = false, Default = 0, HelpText = "height for the screenshot")]
            public int ScreenH { get; set; }
        }
        private object HandleParseError(IEnumerable<Error> errs)
        {
            closeForm();
            return 1;
        }
        private object RunOptionsAndReturnExitCode(Options options)
        {
            _options = options;
            return null;
        }
        public ScreenShotForm()
        {
            string[] args = Environment.GetCommandLineArgs();
            var result = CommandLine.Parser.Default.ParseArguments<Options>(args).MapResult(
                (opts) => RunOptionsAndReturnExitCode(opts),
                errs => HandleParseError(errs));
            path = _options.Path;
            noClose = _options.NoClose;
            if(_options.Url != null)
                _options.Url = _options.Url.Replace("\"", "");
            
            InitializeComponent();

            InitBrowser();
            BrowserSetup(_options.Url, _options.Width, _options.Height);
        }

        public void InitBrowser()
        {
            var settings = new CefSettings();
            //this may be needed on lower-end computers
            settings.CefCommandLineArgs.Add("disable-gpu");
            Cef.Initialize(settings);
        }

        public void BrowserSetup(string url, int width, int height)
        {
            label.Text = "Loading " + url + " it may take a bit";
            
            browser = new ChromiumWebBrowser(url);

            chromiumWebBrowser.Controls.Add(browser);
            chromiumWebBrowser.Width = width;
            chromiumWebBrowser.Height = height;

            this.ClientSize = new System.Drawing.Size(width + 40, height + 70);

            chromiumWebBrowser.Load(url);
        }

        //Submit
        private void Submit_Click(object sender, EventArgs e)
        {
            //Updates on what the is being loaded
            label.Text = "Loading " + textBox.Text + " it may take a bit";
            
            if (File.Exists(path))
            {
                while (Char.IsDigit(path[path.Length - 5]))        
                    path = path.Remove(path.Length - 5, 1);
                path = path.Insert(path.Length - 4, variableNum.ToString());
            }

            //This makes the 2 browsers load the same thing (1 browser is what we see, and the other is what is screenshotted)
            browser = new ChromiumWebBrowser(textBox.Text);
            chromiumWebBrowser.Load(textBox.Text);

            chromiumWebBrowser.Controls.Clear();
            chromiumWebBrowser.Controls.Add(browser);
            variableNum++;

        }

        //If the browser is changed
        private void WebBrowser_LoadingStateChanged(object sender, LoadingStateChangedEventArgs e)
        {
 

                //Once the Page is loaded
                if (e.IsLoading == false)
                {
                //needs to be invoked since they are on different threads
                label.Invoke(new MethodInvoker(delegate {; label.Text = chromiumWebBrowser.Address + " is loaded and the path is " + path; }));

                if (_options.ScreenW == 0)
                    _options.ScreenW = _options.Width - _options.ScreenX;
                if (_options.ScreenH == 0)
                     _options.ScreenH = _options.Height - _options.ScreenY;


                //Takes the screenshot
                Bitmap theScreenshot = ControlSnapshot.Snapshot(browser, _options.ScreenX, _options.ScreenY, _options.ScreenW, _options.ScreenH);
                
                theScreenshot.Save(@path, ImageFormat.Png);

                if (noClose == false)
                    closeForm();
            }
        }

        public void closeForm()
        {
            this.Invoke(new MethodInvoker(delegate {; this.Close(); }));
        }

    }
}