src/Prospect.Server.Api/Controllers/AdminController.cs

@@ -4,6 +4,8 @@ using System.Text;
 using System.Text.Json;
 using Microsoft.AspNetCore.Mvc;
 using Prospect.Server.Api.Services.Database;
+using Prospect.Server.Api.Services.Database.Models;
+using Prospect.Server.Api.Services.Steam;
 using Prospect.Server.Api.Services.UserData;
 
 namespace Prospect.Server.Api.Controllers;
@@ -18,14 +20,16 @@ public class AdminController : ControllerBase
     private readonly DbEntityService _entityService;
     private readonly DbUserDataService _userDataService;
     private readonly TitleDataService _titleDataService;
+    private readonly SteamWebApiService _steamWebApi;
 
     public AdminController(DbUserService userService, DbEntityService entityService,
-        DbUserDataService userDataService, TitleDataService titleDataService)
+        DbUserDataService userDataService, TitleDataService titleDataService, SteamWebApiService steamWebApi)
     {
         _userService = userService;
         _entityService = entityService;
         _userDataService = userDataService;
         _titleDataService = titleDataService;
+        _steamWebApi = steamWebApi;
     }
 
     // ---------- pages ----------
@@ -82,7 +86,8 @@ public class AdminController : ControllerBase
         }
 
         var sb = new StringBuilder();
-        sb.Append($"<form method='get' class='search'><input name='q' placeholder='Rechercher nom / id / steam…' value='{Esc(q ?? "")}'/><button class='btn'>Rechercher</button></form>");
+        sb.Append($"<form method='get' class='search'><input name='q' placeholder='Rechercher nom / id / steam…' value='{Esc(q ?? "")}'/><button class='btn'>Rechercher</button>" +
+                  "<a class='btn' href='/admin/backfill-names' title='Récupère les pseudos Steam des comptes sans nom'>Backfill pseudos Steam</a></form>");
         sb.Append($"<p class='muted'>{users.Count} joueur(s)</p>");
         sb.Append("<table><thead><tr><th>DisplayName</th><th>PlayFab Id</th><th>Entity Id</th><th>Auth</th><th></th></tr></thead><tbody>");
         foreach (var u in users.OrderBy(u => u.DisplayName))
@@ -179,6 +184,38 @@ public class AdminController : ControllerBase
         return Html(Layout("TitleData · " + key, $"<h2 class='mono'>{Esc(key)}</h2>" + body));
     }
 
+    [HttpGet("backfill-names")]
+    public async Task<IActionResult> BackfillNames()
+    {
+        if (!IsLan()) return Denied();
+        if (!_steamWebApi.Enabled)
+            return Html(Layout("Backfill", "<p class='muted'>Steam Web API non configurée (clé absente).</p><p><a class='btn' href='/admin/players'>← Joueurs</a></p>"));
+
+        var users = await _userService.GetAllAsync();
+        int updated = 0, skipped = 0, failed = 0;
+        var rows = new StringBuilder();
+        foreach (var u in users)
+        {
+            if (!string.IsNullOrEmpty(u.DisplayName) && u.DisplayName != "Unknown") { skipped++; continue; }
+            var steam = u.Auth?.FirstOrDefault(a => a.Type == PlayFabUserAuthType.Steam)?.Key;
+            if (string.IsNullOrEmpty(steam)) { skipped++; continue; }
+
+            var persona = await _steamWebApi.GetPersonaNameAsync(steam);
+            if (!string.IsNullOrWhiteSpace(persona))
+            {
+                await _userService.UpdateDisplayNameAsync(u.Id, persona);
+                updated++;
+                rows.Append($"<tr><td class='mono small'>{Esc(u.Id)}</td><td>{Esc(persona)}</td></tr>");
+            }
+            else { failed++; }
+        }
+
+        var body = $"<h2>Backfill des pseudos Steam</h2><p class='muted'>{updated} mis à jour · {skipped} ignorés · {failed} échec(s)</p>" +
+                   (updated > 0 ? $"<table><thead><tr><th>PlayFabId</th><th>Nouveau nom</th></tr></thead><tbody>{rows}</tbody></table>" : "") +
+                   "<p><a class='btn' href='/admin/players'>← Joueurs</a></p>";
+        return Html(Layout("Backfill", body));
+    }
+
     // ---------- helpers ----------
 
     private bool IsLan()

src/Prospect.Server.Api/Controllers/ClientController.cs

@@ -32,6 +32,7 @@ public class ClientController : Controller
     private readonly DbEntityService _entityService;
     private readonly UserDataService _userDataService;
     private readonly TitleDataService _titleDataService;
+    private readonly Prospect.Server.Api.Services.Steam.SteamWebApiService _steamWebApi;
 
     public ClientController(ILogger<ClientController> logger,
         IOptions<PlayFabSettings> settings,
@@ -39,7 +40,8 @@ public class ClientController : Controller
         DbUserService userService,
         DbEntityService entityService,
         UserDataService userDataService,
-        TitleDataService titleDataService)
+        TitleDataService titleDataService,
+        Prospect.Server.Api.Services.Steam.SteamWebApiService steamWebApi)
     {
         _settings = settings.Value;
         _logger = logger;
@@ -48,6 +50,7 @@ public class ClientController : Controller
         _entityService = entityService;
         _userDataService = userDataService;
         _titleDataService = titleDataService;
+        _steamWebApi = steamWebApi;
     }
 
     [AllowAnonymous]
@@ -63,6 +66,19 @@ public class ClientController : Controller
                 var userSteamId = ticket.SteamId.ToString();
 
                 var user = await _userService.FindOrCreateAsync(PlayFabUserAuthType.Steam, userSteamId);
+
+                // Backfill the display name from the Steam persona when we don't have a real
+                // one yet (accounts are created as "Unknown"; the client never sends a name).
+                if (string.IsNullOrEmpty(user.DisplayName) || user.DisplayName == "Unknown")
+                {
+                    var persona = await _steamWebApi.GetPersonaNameAsync(userSteamId);
+                    if (!string.IsNullOrWhiteSpace(persona))
+                    {
+                        await _userService.UpdateDisplayNameAsync(user.Id, persona);
+                        user.DisplayName = persona;
+                    }
+                }
+
                 var entity = await _entityService.FindOrCreateAsync(user.Id);
 
                 var userTicket = _authTokenService.GenerateUser(entity);

src/Prospect.Server.Api/Services/Steam/SteamWebApiService.cs

@@ -0,0 +1,55 @@
+using System.Text.Json;
+
+namespace Prospect.Server.Api.Services.Steam;
+
+// Resolves a Steam persona (display) name from a SteamID64 via the Steam Web API.
+// PlayFab does this server-side too; our emulator only gets the SteamID from the auth
+// ticket, so the real name needs an API key. Inert (no-op) when no key is configured.
+public class SteamWebApiService
+{
+    private static readonly HttpClient Http = new() { Timeout = TimeSpan.FromSeconds(5) };
+
+    private readonly string? _apiKey;
+    private readonly ILogger<SteamWebApiService> _logger;
+
+    public SteamWebApiService(IConfiguration configuration, ILogger<SteamWebApiService> logger)
+    {
+        _apiKey = configuration["SteamWebApiKey"];
+        _logger = logger;
+    }
+
+    public bool Enabled => !string.IsNullOrWhiteSpace(_apiKey);
+
+    public async Task<string?> GetPersonaNameAsync(string steamId64)
+    {
+        if (!Enabled)
+        {
+            return null;
+        }
+
+        try
+        {
+            var url = $"https://api.steampowered.com/ISteamUser/GetPlayerSummaries/v2/?key={_apiKey}&steamids={steamId64}";
+            var json = await Http.GetStringAsync(url);
+            using var doc = JsonDocument.Parse(json);
+            if (doc.RootElement.TryGetProperty("response", out var response) &&
+                response.TryGetProperty("players", out var players) &&
+                players.ValueKind == JsonValueKind.Array)
+            {
+                foreach (var player in players.EnumerateArray())
+                {
+                    if (player.TryGetProperty("personaname", out var name))
+                    {
+                        return name.GetString();
+                    }
+                }
+            }
+        }
+        catch (Exception e)
+        {
+            _logger.LogWarning(e, "Steam GetPlayerSummaries failed for {SteamId}", steamId64);
+        }
+
+        return null;
+    }
+}

src/Prospect.Server.Api/Startup.cs

@@ -30,6 +30,8 @@ public class Startup
         services.AddSingleton<UserDataService>();
         services.AddSingleton<TitleDataService>();
 
+        services.AddSingleton<Prospect.Server.Api.Services.Steam.SteamWebApiService>();
+
         services.AddSingleton<DbUserService>();
         services.AddSingleton<DbEntityService>();