Add Steam auth, platform validators & name gen

RecNet.Infrastructure/Services/Steam/SteamAuthService.cs

@@ -0,0 +1,89 @@
+using System.Net.Http.Json;
+using System.Text.Json.Serialization;
+using Microsoft.Extensions.Options;
+using RecNet.Application.Common.Interfaces;
+using RecNet.Application.Common.Steam;
+using SteamApi.Models.Steam.Player;
+using SteamApi.Models.Steam.Responses;
+
+namespace RecNet.Infrastructure.Services.Steam;
+
+public class SteamAuthService(
+    HttpClient httpClient,
+    IOptions<SteamOptions> options) : ISteamAuthService
+{
+    private readonly SteamOptions _options = options.Value;
+    
+    public async Task<SteamAuthResult> AuthorizeAsync(
+        string ticket,
+        uint appId,
+        CancellationToken ct = default)
+    {
+        if (string.IsNullOrWhiteSpace(ticket))
+            return SteamAuthResult.Failure();
+        
+        if (appId != _options.AppId)
+            return SteamAuthResult.Failure();
+        
+        var steamId = await AuthenticateTicketAsync(ticket, ct);
+        if (steamId is null)
+            return SteamAuthResult.Failure();
+
+        var profile = await GetProfileAsync(steamId, ct);
+
+        return SteamAuthResult.Success(
+            steamId,
+            profile?.PersonaName);
+    }
+    
+    private async Task<string?> AuthenticateTicketAsync(
+        string ticket,
+        CancellationToken ct)
+    {
+        var url =
+            "ISteamUserAuth/AuthenticateUserTicket/v0001/" +
+            $"?key={Uri.EscapeDataString(_options.ApiKey)}" +
+            $"&appid={_options.AppId}" +
+            $"&ticket={Uri.EscapeDataString(ticket)}";
+
+        var response = await httpClient.GetAsync(url, ct);
+        if (!response.IsSuccessStatusCode)
+            return null;
+
+        var body = await response.Content.ReadFromJsonAsync<SteamResponse<SteamAuthResponse>>(
+            cancellationToken: ct);
+
+        return body?.Response?.Params?.SteamId;
+    }
+
+    private async Task<PlayerSummary?> GetProfileAsync(
+        string steamId,
+        CancellationToken ct)
+    {
+        var url =
+            "ISteamUser/GetPlayerSummaries/v0002/" +
+            $"?key={Uri.EscapeDataString(_options.ApiKey)}" +
+            $"&steamids={Uri.EscapeDataString(steamId)}";
+
+        var response = await httpClient.GetAsync(url, ct);
+        if (!response.IsSuccessStatusCode)
+            return null;
+
+        var body = await response.Content.ReadFromJsonAsync<SteamResponse<PlayerSummariesResponse>>(
+            cancellationToken: ct);
+
+        return body?.Response?.Players.FirstOrDefault();
+    }
+    
+    private class SteamAuthResponse
+    {
+        [JsonPropertyName("params")]
+        public SteamAuthParamsResponse? Params { get; set; }
+    }
+
+    private class SteamAuthParamsResponse
+    {
+        [JsonPropertyName("steamid")]
+        public required string SteamId { get; set; }
+    }
+}

RecNet.Infrastructure/Services/Steam/SteamAuthValidator.cs

@@ -0,0 +1,48 @@
+using System.Text.Json;
+using System.Text.Json.Serialization;
+using RecNet.Application.Common.Interfaces;
+using RecNet.Application.Common.PlatformAuth;
+using RecNet.Domain.Common;
+
+namespace RecNet.Infrastructure.Services.Steam;
+
+public class SteamAuthValidator(ISteamAuthService steamAuthService) : IPlatformAuthValidator
+{
+    public PlatformType PlatformType 
+        => PlatformType.Steamworks;
+    
+    public async Task<PlatformAuthResult> ValidateAsync(
+        string platformAuthentication,
+        string platformId,
+        CancellationToken ct = default)
+    {
+        var steamParams = JsonSerializer.Deserialize<SteamPlatformAuth>(platformAuthentication);
+        if (steamParams == null)
+            return PlatformAuthResult.Failure("Invalid authentication");
+        
+        var result = await steamAuthService.AuthorizeAsync(steamParams.Ticket, steamParams.AppId.AppId, ct);
+
+        if (!result.Succeeded || result.SteamId is null)
+            return PlatformAuthResult.Failure("Invalid authentication");
+
+        if (!string.IsNullOrWhiteSpace(platformId) &&
+            platformId != result.SteamId)
+            return PlatformAuthResult.Failure("Nice try");
+
+        return PlatformAuthResult.Success(result.DisplayName);
+    }
+
+    private sealed class SteamPlatformAuth
+    {
+        public required string Ticket { get; set; }
+        
+        public required SteamAppIdAuth AppId { get; set; }
+    }
+    
+    // Splooty, why did you set it up like this ;-;
+    private sealed class SteamAppIdAuth 
+    {
+        [JsonPropertyName("m_AppId")]
+        public required uint AppId { get; set; }
+    }
+}

RecNet.Infrastructure/Services/Steam/SteamOptions.cs

@@ -0,0 +1,8 @@
+namespace RecNet.Infrastructure.Services.Steam;
+
+public class SteamOptions
+{
+    public string ApiKey { get; set; } = string.Empty;
+    public uint AppId { get; set; } = 480; // Spacewar
+    public string Identity { get; set; } = "recnet";
+}