ModsUpdater.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http;
using System.Security.Cryptography;
using Cysharp.Threading.Tasks;
using ModLoader;
using SFS.Input;
using SFS.IO;
using SFS.UI;
using UnityEngine;

namespace UITools
{
    static class ModsUpdater
    {
        static readonly HttpClient Http = new();
        static readonly MD5 MD5 = MD5.Create();
        static int loadedFiles;

        public static async UniTask UpdateAll()
        {
            try
            {
                IUpdatable[] mods = Loader.main.GetAllMods().OfType<IUpdatable>().ToArray();
                if (mods.Length == 0)
                    return;

                foreach (IUpdatable mod in mods)
                    await Update(mod);
            }
            catch (Exception e)
            {
                Debug.LogError(e);
            }
            finally
            {
                if (loadedFiles > 0)
                    MenuGenerator.OpenConfirmation(CloseMode.Current,
                        () => "Some files were updated. Do you want to restart the game?", () => "Restart",
                        ApplicationUtility.Relaunch);
            }
        }

        static async UniTask Update(IUpdatable mod)
        {
            foreach (KeyValuePair<string, FilePath> file in mod.UpdatableFiles)
            {
                string link =
                    $"https://files.cucumber-space.online/api/hashes/md5?file={Uri.EscapeDataString(file.Key)}";
                HttpResponseMessage response = await Http.GetAsync(link);

                if (!response.IsSuccessStatusCode)
                    continue;

                byte[] md5HashLocal = file.Value.FileExists()
                    ? MD5.ComputeHash(file.Value.ReadBytes())
                    : Array.Empty<byte>();
                byte[] md5HashRemote = Convert.FromBase64String(await response.Content.ReadAsStringAsync());

                if (md5HashLocal.SequenceEqual(md5HashRemote))
                    continue;
                if (!await MenuGenerator.OpenConfirmationAsync(CloseMode.Current,
                        () => $"Update for {(mod as Mod)?.DisplayName} is available. Update?", () => "Update"))
                    continue;

                response = await Http.GetAsync(file.Key);

                byte[] data = await response.Content.ReadAsByteArrayAsync();
                if (data == null)
                    continue;
                file.Value.WriteBytes(data);
                loadedFiles += 1;
            }
        }
    }

    /// <summary>
    ///     Implement this interface on main mod class if you want it to be updated at game start
    /// </summary>
    public interface IUpdatable
    {
        /// <summary>
        ///     Returns dictionary of files that should be updated
        ///     string is web link, FilePath is path where file will downloaded
        /// </summary>
        /// <returns></returns>
        public Dictionary<string, FilePath> UpdatableFiles { get; }
    }
}