YouTube thumbs and data downloader V1.5

/*
 * Created by SharpDevelop.
 * User: Admin
 * Date: 5/10/2021
 * Time: 8:52 PM
 *
 * This is V1.5 of the YouTube thumbnail and data downloader. It will get thumbs and video ID, title, viewCount, uploadDate and store
 * them to jpgs and an index file called 1A_YouTube.txt. It's meant to be used along with a downloader like mediahuman or youtube-dl
 * to get the extra information that may be needed for a future offline video archival system.
 */
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Windows.Forms;
using System.Web;
using System.Net;
using System.Text;
using System.Linq;
using System.IO;

namespace ThumbExtractor
{
    public partial class MainForm : Form
    {
        public WebClient happy;

        public struct VidData
        {
            public string title;
            public string ID;
            public UInt32 views;
            public DateTime date;
        }
        public List<VidData> video;

        public MainForm()
        {
            InitializeComponent();
            happy = new WebClient();
            video = new List<VidData>();
        }
        void BtnSaveClick(object sender, EventArgs e)
        {
            int count = txtThumb.Lines.Length;
            int cur = 0;
            int i = 0;

            if (txtThumb.Text == "")
            {
                MessageBox.Show("The URL (video list) is empty. Don't cha know?", "Empty", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                return;
            }
            if (txtPath.Text == "")
            {
                MessageBox.Show("You need to browse for a directory or type one in first!", "Select Folder Please", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                return;
            }
            if (!Directory.Exists(txtPath.Text))
            {
                MessageBox.Show("The directory you put in the box does not exist. Please make it first.", "Folder does not exist", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                return;
            }
            List<string> fixedLines = new List<string>();
            foreach (string line in txtThumb.Lines)
            {
                if (line != "")
                {
                    if (!line.Contains("youtu.be") && !line.Contains("youtube.com"))
                    {
                        MessageBox.Show("There's an invalid URL in there!", "Invalid", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                        return;
                    }
                    if (!line.Contains("/channel/"))
                    {
                        if (line.Contains("&"))
                            fixedLines.Add(line.Substring(0, line.IndexOf('&')));
                        else
                            fixedLines.Add(line);
                    }
                }
            }
            txtThumb.Lines = fixedLines.ToArray();
            txtThumb.Text = string.Join(Environment.NewLine, txtThumb.Lines.Distinct());
            count = txtThumb.Lines.Length;
            txtThumb.Refresh();

            if (!txtPath.Text.EndsWith("\\"))
                txtPath.Text += "\\";

            btnSave.Enabled = false;
            prog.Maximum = count;
            prog.Value = 0;
            video.Clear();

            foreach (string vid in txtThumb.Lines)
            {
                if (chkData.Checked) GetData(vid); else GetThumb(vid);
                cur++;
                btnSave.Text = cur.ToString() + " / " + count.ToString();
                prog.Value = cur;
                Refresh();
            }
            if (chkData.Checked)
            {
                video.Sort((x, y) => DateTime.Compare(y.date, x.date));
                string[] filed = new string[video.Count];
                for (i = 0; i < filed.Length; i++)
                    filed[i] = video[i].title + "; " + video[i].ID + "; " + video[i].views + "; " + video[i].date.ToShortDateString();
                File.WriteAllLines(txtPath.Text + "1A_YouTube.txt", filed);
                btnSave.Text = "Save Data";
            }
            else
                btnSave.Text = "Save Thumbs";
            btnSave.Enabled = true;
        }

        public void GetThumb(string url)
        {
            //another way for later - provides more data: https://www.youtube.com/get_video_info?video_id=
            //but it's much slower

            string api = "https://noembed.com/embed?url=" + url;
            string ytCode;
            if (url.Contains("youtu.be"))
                ytCode = url.Substring(url.LastIndexOf('/') + 1);
            else
                ytCode = GetArgs(url, "v", '?');
            ServicePointManager.SecurityProtocol = (SecurityProtocolType)3072;
            string result = happy.DownloadString(api);
            string theTitle = GetElement(ref result, "title");
            string toLoad = "https://i.ytimg.com/vi/" + ytCode + "/hqdefault.jpg";
            string fixedFile = txtPath.Text + ScrubFileName(theTitle) + ".jpg";
            happy.DownloadFile(toLoad, fixedFile);
            picPrev.ImageLocation = fixedFile;
            if (File.Exists(picPrev.ImageLocation))
                picPrev.Load();
        }

        public void GetData(string url)
        {
            string api = "https://www.youtube.com/get_video_info?video_id=";
            string ytCode;
            string scaped;
            if (url.Contains("youtu.be"))
                ytCode = url.Substring(url.LastIndexOf('/') + 1);
            else
                ytCode = GetArgs(url, "v", '?');
            api += ytCode;
            ServicePointManager.SecurityProtocol = (SecurityProtocolType)3072;
            //THE DAMN THING JUST DOESN'T CONNECT SOMETIMES, SO WE JUST HAVE TO KEEP TRYING - ANYBODY UNDERSTAND THE PROBLEM?
            while (true)
            {
                try { scaped = happy.DownloadString(api); break; }
                catch { }
            }
            string result = Uri.UnescapeDataString(scaped);
            VidData curVid = new VidData();
            curVid.title = ScrubFileName(GetElement(ref result, "title"));
            curVid.views = Convert.ToUInt32(GetElement(ref result, "viewCount"));
            curVid.date = DateTime.Parse(GetElement(ref result, "publishDate"));
            curVid.ID = ytCode;
            video.Add(curVid);
        }

        public string GetElement(ref string data, string toFind)
        {
            string fullFind = "\"" + toFind + "\":\"";
            int loc = data.IndexOf(fullFind);
            loc += fullFind.Length;
            return data.Substring(loc, data.IndexOf('"', loc) - loc).Replace('+', ' ');
        }

        public string GetArgs(string args, string key, char query)
        {
            int iqs = args.IndexOf(query);
            return iqs == -1
                ? string.Empty
                : HttpUtility.ParseQueryString(iqs < args.Length - 1
                    ? args.Substring(iqs + 1) : string.Empty)[key];
        }

        public string ScrubFileName(string value)
        {
           StringBuilder sb = new StringBuilder(value);
           foreach (char item in Path.GetInvalidFileNameChars())
           {
              sb.Replace(item.ToString(), "");
           }
           return sb.ToString();
        }
        void BtnHelpClick(object sender, EventArgs e)
        {
            MessageBox.Show("You paste a list of youtube video links in the box. For getting large batches of links, use the firefox add-on called \"copy selected links\". " +
                            "You then select all the videos (if more than about 50, then do it in segments) and copy them. If there are duplicates or erronious ones, this " +
                            "software should remove them when you press the button. It will also remove any parameters other than the video link/ID. The images will be stored " +
                            "in the directory you select with the browse button and will be named with the title of the video. Save data will save all the videos info like " +
                            "title, date, ID, etc. to a file called 1A_YouTube.txt located in the same directory. This is intended to be used in conjunction with a good downloader " +
                            "like mediahuman or youtube-dl which will get the youtube videos or audio files to go along with this.\nSomeday I may make a full youtube archival " +
                            "indexer. If you have a request, you can send a message on my website.\n\n(C) 2021 DosaidSoft.com V" + Application.ProductVersion, "Help and About", MessageBoxButtons.OK, MessageBoxIcon.Information);
        }
        void BtnBrowseClick(object sender, EventArgs e)
        {
            if (fBrowser.ShowDialog() == DialogResult.OK)
            {
                if (!fBrowser.SelectedPath.EndsWith("\\"))
                    txtPath.Text = fBrowser.SelectedPath + "\\";
                else
                    txtPath.Text = fBrowser.SelectedPath;
            }
        }
        void ChkDataCheckedChanged(object sender, EventArgs e)
        {
            btnSave.Text = chkData.Checked ? "Save Data" : "Save Thumbs";
        }
    }
}