// HttpClient lifecycle management best practices:
// https://learn.microsoft.com/dotnet/fundamentals/networking/http/httpclient-guidelines#recommended-use
private static readonly HttpClient httpClient = new HttpClient();

// using System.Net.Http.Headers;
// using MovieCollection.OpenSubtitles;

var options = new OpenSubtitlesOptions
{
    ApiKey = "your-api-key",
    ProductInformation = new ProductHeaderValue("your-app-name", "your-app-version"),
};

var service = new OpenSubtitlesService(httpClient, options);

// using System.Net.Http.Headers;

var product = new ProductInfoHeaderValue("your-app-name", "your-app-version");
httpClient.DefaultRequestHeaders.UserAgent.Add(product);

var search = new NewSubtitleSearch
{
    ImdbId = 11204094,
};

var result = await service.SearchSubtitlesAsync(search);

var search = new NewSubtitleSearch
{
    Query = "Iron Man",
    Year = 2008,
};

var search = new NewSubtitleSearch
{
    Query = "Rick and Morty",
    SeasonNumber = 5,
    EpisodeNumber = 10,
};

string filePath = "D:\\path-to-file\\";

var search = new NewSubtitleSearch
{
    // For best results with automatic searching based on file analysis,
    // send the file name as a query together with the moviehash.
    Query = Path.GetFileName(filePath),

    // Open Subtitles is using a special hash function to match subtitle files against movie files.
    // Hash is not dependent on file name of movie file.
    MovieHash = OpenSubtitlesHasher.GetFileHash(filePath),
};