nadekobot/src/NadekoBot/Modules/Searches/_Common/StreamNotifications/Providers/TwitchProvider.cs

using NadekoBot.Db.Models;
using Newtonsoft.Json;
using System.Text.RegularExpressions;

namespace NadekoBot.Modules.Searches.Common.StreamNotifications.Providers;

public class TwitchProvider : Provider
{
    private static Regex Regex { get; } = new(@"twitch.tv/(?<name>.+[^/])/?",
        RegexOptions.Compiled | RegexOptions.IgnoreCase);

    public override FollowedStream.FType Platform
        => FollowedStream.FType.Twitch;

    public override IReadOnlyDictionary<string, DateTime> FailingStreams
        => _failingStreams;

    private readonly IHttpClientFactory _httpClientFactory;

    public TwitchProvider(IHttpClientFactory httpClientFactory)
        => _httpClientFactory = httpClientFactory;

    public override void ClearErrorsFor(string login)
        => _failingStreams.TryRemove(login, out _);

    public override Task<bool> IsValidUrl(string url)
    {
        var match = Regex.Match(url);
        if (!match.Success)
            return Task.FromResult(false);

        // var username = match.Groups["name"].Value;
        return Task.FromResult(true);
    }

    public override Task<StreamData?> GetStreamDataByUrlAsync(string url)
    {
        var match = Regex.Match(url);
        if (match.Success)
        {
            var name = match.Groups["name"].Value;
            return GetStreamDataAsync(name);
        }

        return Task.FromResult<StreamData?>(null);
    }

    public override async Task<StreamData?> GetStreamDataAsync(string id)
    {
        var data = await GetStreamDataAsync(new List<string>
        {
            id
        });

        return data.FirstOrDefault();
    }

    public override async Task<IReadOnlyCollection<StreamData>> GetStreamDataAsync(List<string> logins)
    {
        if (logins.Count == 0)
            return new List<StreamData>();

        using var http = _httpClientFactory.CreateClient();
        http.DefaultRequestHeaders.Add("Client-Id", "67w6z9i09xv2uoojdm9l0wsyph4hxo6");
        http.DefaultRequestHeaders.Add("Accept", "application/vnd.twitchtv.v5+json");

        var toReturn = new List<StreamData>();
        foreach (var login in logins)
            try
            {
                // get id based on the username
                var idsStr = await http.GetStringAsync($"https://api.twitch.tv/kraken/users?login={login}");
                var userData = JsonConvert.DeserializeObject<TwitchUsersResponseV5>(idsStr);
                var user = userData?.Users.FirstOrDefault();

                // if user can't be found, skip, it means there is no such user
                if (user is null)
                    continue;

                // get stream data
                var str = await http.GetStringAsync($"https://api.twitch.tv/kraken/streams/{user.Id}");
                var resObj = JsonConvert.DeserializeAnonymousType(str,
                    new
                    {
                        Stream = new TwitchResponseV5.Stream()
                    });

                // if stream is null, user is not streaming
                if (resObj?.Stream is null)
                {
                    // if user is not streaming, get his offline banner
                    var chStr = await http.GetStringAsync($"https://api.twitch.tv/kraken/channels/{user.Id}");
                    var ch = JsonConvert.DeserializeObject<TwitchResponseV5.Channel>(chStr)!;

                    toReturn.Add(new()
                    {
                        StreamType = FollowedStream.FType.Twitch,
                        Name = ch.DisplayName,
                        UniqueName = ch.Name,
                        Title = ch.Status,
                        IsLive = false,
                        AvatarUrl = ch.Logo,
                        StreamUrl = $"https://twitch.tv/{ch.Name}",
                        Preview = ch.VideoBanner // set video banner as the preview,
                    });
                    continue; // move on
                }

                toReturn.Add(ToStreamData(resObj.Stream));
                _failingStreams.TryRemove(login, out _);
            }
            catch (Exception ex)
            {
                Log.Warning("Something went wrong retreiving {StreamPlatform} stream data for {Login}: {ErrorMessage}",
                    Platform,
                    login,
                    ex.Message);
                _failingStreams.TryAdd(login, DateTime.UtcNow);
            }

        return toReturn;
    }

    private StreamData ToStreamData(TwitchResponseV5.Stream stream)
        => new()
        {
            StreamType = FollowedStream.FType.Twitch,
            Name = stream.Channel.DisplayName,
            UniqueName = stream.Channel.Name,
            Viewers = stream.Viewers,
            Title = stream.Channel.Status,
            IsLive = true,
            Preview = stream.Preview.Large,
            Game = stream.Channel.Game,
            StreamUrl = $"https://twitch.tv/{stream.Channel.Name}",
            AvatarUrl = stream.Channel.Logo
        };
}