adding log camps

microservices/LocationsApi/Services/LocationService.cs

@@ -10,6 +10,7 @@ public class LocationService
     private readonly int _homeMinDistance;
     private readonly int _homeSearchRadius;
     private readonly int _visibilityDepth;
+    private readonly int _logCampWoodPerMinute;
 
     public LocationService(IConfiguration cfg, ResourceService resources)
     {
@@ -22,6 +23,9 @@ public class LocationService
         _homeMinDistance = int.TryParse(cfg["World:HomeMinDistance"], out var minDistance) ? Math.Max(1, minDistance) : 8;
         _homeSearchRadius = int.TryParse(cfg["World:HomeSearchRadius"], out var searchRadius) ? Math.Max(_homeMinDistance, searchRadius) : 80;
         _visibilityDepth = int.TryParse(cfg["World:VisibilityDepth"], out var visibilityDepth) ? Math.Max(0, visibilityDepth) : 3;
+        _logCampWoodPerMinute = int.TryParse(cfg["Buildings:LogCampWoodPerMinute"], out var logCampWoodPerMinute)
+            ? Math.Max(1, logCampWoodPerMinute)
+            : 5;
 
         var coordinateIndex = Builders<Location>.IndexKeys
             .Ascending(x => x.Q)
@@ -111,6 +115,53 @@ public class LocationService
         return await UpsertAsync(new UpsertLocationRequest { Q = q, R = r, Terrain = "Field" }, username);
     }
 
+    public async Task<Location?> BuildAsync(BuildLocationRequest request, string username)
+    {
+        if (!string.Equals(request.BuildingType, "LogCamp", StringComparison.OrdinalIgnoreCase))
+        {
+            throw new ArgumentException("Unsupported building type.", nameof(request.BuildingType));
+        }
+
+        var location = await GetAsync(request.Q, request.R);
+        if (location is null ||
+            !string.Equals(location.OwnerUsername, username, StringComparison.OrdinalIgnoreCase))
+        {
+            return null;
+        }
+
+        if (!string.IsNullOrWhiteSpace(location.BuildingType))
+        {
+            throw new InvalidOperationException("This location already has a building.");
+        }
+
+        if (!string.Equals(location.Terrain, "Forest", StringComparison.OrdinalIgnoreCase))
+        {
+            throw new InvalidOperationException("Log Camps can only be built on Forest territory.");
+        }
+
+        var now = DateTime.UtcNow;
+        var update = Builders<Location>.Update
+            .Set(x => x.BuildingType, "LogCamp")
+            .Set(x => x.BuildingBuiltAtUtc, now)
+            .Set(x => x.UpdatedAtUtc, now);
+
+        var updated = await _locations.FindOneAndUpdateAsync(
+            x => x.Id == location.Id && x.OwnerUsername == username && x.BuildingType == null,
+            update,
+            new FindOneAndUpdateOptions<Location>
+            {
+                ReturnDocument = ReturnDocument.After
+            });
+
+        if (updated is null)
+        {
+            throw new InvalidOperationException("This location already has a building.");
+        }
+
+        await _resources.AddWoodGenerationAsync(username, _logCampWoodPerMinute);
+        return updated;
+    }
+
     public async Task<Location?> GetHomeAsync(string username) =>
         await _locations.Find(x => x.OwnerUsername == username && x.Kind == "Home").FirstOrDefaultAsync();