ČSFD exporter (to IMDb format)

CsfdExporter.csproj

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net5.0</TargetFramework>
    <Nullable>enable</Nullable>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="HtmlAgilityPack" Version="1.11.30" />
  </ItemGroup>

</Project>

Program.cs

using HtmlAgilityPack;
using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;
using System.Text.RegularExpressions;

try
{
    if (args.Length < 1)
    {
        Console.Error.WriteLine("Missing argument: UserId");
        return 2;
    }
    if (args.Length < 2)
    {
        Console.Error.WriteLine("Missing argument: OutputPath");
        return 2;
    }

    var userId = args[0];
    var outputPath = args[1];

    using var api = new CsfdApi("https://www.csfd.cz");

    using (var writer = new StreamWriter(outputPath, append: false, Encoding.UTF8))
    {
        writer.WriteLine("Const,Your Rating,Date Rated,Title,URL,Title Type,IMDb Rating,Runtime (mins),Year,Genres,Num Votes,Release Date,Directors");
        foreach (var x in api.GetUserRatings(userId).Where(x => x.ImdbId != null))
        {
            var imdb = "tt" + x.ImdbId;
            var rating = (int)Math.Round(1 + (x.Rating * (9d / 5d)));
            var date = x.Date.ToString("yyyy-MM-dd", CultureInfo.InvariantCulture);
            var title = Regex.Replace(x.Title, @"\W", "-");
            writer.WriteLine($"{imdb},{rating},{date},{title},,movie,,,,,,,");
        }
    }

    return 0;
}
catch (Exception ex)
{
    Console.Error.WriteLine(ex);
    return 1;
}


internal record UserRating(string Title, int Rating, DateTime Date, string CsfdId, string ImdbId);

internal sealed class CsfdApi : IDisposable
{
    private readonly UrlBuilder _urlBuilder;
    private readonly HttpsWebClient _webClient;
    private bool _disposed;

    public CsfdApi(string rootUrl)
    {
        _urlBuilder = new UrlBuilder(rootUrl);
        _webClient = new HttpsWebClient();
    }

    public void Dispose()
    {
        if (_disposed)
        {
            return;
        }

        _webClient.Dispose();
        _disposed = true;

        GC.SuppressFinalize(this);
    }

    public IEnumerable<UserRating> GetUserRatings(string userId)
    {
        var documentNode = DownloadHtml(_urlBuilder.UserRating(userId, 1));
        var pageCount = 1 + documentNode.SelectNodes("//div[@class='paginator text'][1]/a[not(@class)]").Count;

        for (var i = 1u; i <= pageCount; i++)
        {
            var nodes = documentNode.SelectNodes("//table[@class='ui-table-list']/tbody/tr");
            foreach (var node in nodes)
            {
                var rating = node.SelectSingleNode("td[2]/img")?.Attributes["alt"].ValueLength ?? 0;
                var date = DateTime.ParseExact(node.SelectSingleNode("td[3]").InnerText, "dd.MM.yyyy", CultureInfo.InvariantCulture);

                var filmNode = node.SelectSingleNode("td[1]/a");
                var csfdId = Regex.Match(filmNode.Attributes["href"].Value, @"^/film/(?<Id>[^-]+)-").Groups["Id"].Value;
                var title = filmNode.InnerText;

                string? imdbId = null;
                var filmDocumentNode = DownloadHtml(_urlBuilder.Film(csfdId));
                var shareLinkNodes = filmDocumentNode.SelectNodes("//div[@id='share']/ul[@class='links']/li/a");
                foreach (var shareLinkNode in shareLinkNodes)
                {
                    var shareLinkUrl = shareLinkNode.Attributes["href"].Value;
                    if (Regex.Match(shareLinkUrl, @"imdb\.com/title/tt(?<Id>[0-9]+)") is { Success: true, Groups: var groups })
                    {
                        imdbId = groups["Id"].Value;
                        break;
                    }
                }

                if (imdbId == null)
                {
                    Console.Error.WriteLine($"Missing IMDb ID for ČSFD ID {csfdId} ({title})");
                    continue;
                }

                var result = new UserRating(title, rating, date, csfdId, imdbId);

                Console.WriteLine(result);
                yield return result;
            }

            if (i < pageCount)
            {
                documentNode = DownloadHtml(_urlBuilder.UserRating(userId, i + 1));
            }
        }
    }

    private HtmlNode DownloadHtml(string url)
    {
        var html = _webClient.DownloadString(url);
        var document = new HtmlDocument();
        document.LoadHtml(html);
        return document.DocumentNode;
    }

    private class HttpsWebClient : WebClient
    {
        protected override WebRequest GetWebRequest(Uri address)
        {
            var request = base.GetWebRequest(address);
            if (request is HttpWebRequest httpRequest)
            {
                httpRequest.AutomaticDecompression = DecompressionMethods.Deflate | DecompressionMethods.GZip;
            }
            return request;
        }
    }

    private class UrlBuilder
    {
        public UrlBuilder(string rootUrl)
        {
            RootUrl = rootUrl;
        }

        private string RootUrl { get; }

        public string Film(string filmId) => $"{RootUrl}/film/{filmId}/prehled/";

        public string UserRating(string userId, uint page) => $"{RootUrl}/uzivatel/{userId}/hodnoceni/strana-{page}/";
    }
}