Adding player sensing

game/scenes/Levels/location_level.gd

@@ -6,6 +6,8 @@ const INVENTORY_API_URL := "https://pinv.ranaze.com/api/inventory"
 const START_SCREEN_SCENE := "res://scenes/UI/start_screen.tscn"
 const SETTINGS_SCENE := "res://scenes/UI/Settings.tscn"
 const CHARACTER_SLOT_COUNT := 6
+const VISIBLE_CHARACTERS_REFRESH_INTERVAL := 5.0
+const HEARTBEAT_INTERVAL := 10.0
 
 @export var tile_size := 8.0
 @export var block_height := 1.0
@@ -34,8 +36,9 @@ const CHARACTER_SLOT_COUNT := 6
 @onready var _inventory_status_label: Label = $InventoryMenu/MarginContainer/Panel/VBoxContainer/ControlsPanel/VBoxContainer/StatusLabel
 
 var _center_coord := Vector2i.ZERO
-var _tiles_root: Node3D
-var _tracked_node: Node3D
+var _tiles_root: Node3D
+var _remote_players_root: Node3D
+var _tracked_node: Node3D
 var _tile_nodes: Dictionary = {}
 var _camera_start_offset := Vector3(0.0, 6.0, 10.0)
 var _border_material: StandardMaterial3D
@@ -53,12 +56,20 @@ var _inventory_request_in_flight := false
 var _character_inventory_items: Array = []
 var _selected_character_item_id := ""
 var _selected_ground_item_id := ""
+var _visible_characters_in_flight := false
+var _heartbeat_in_flight := false
+var _visible_character_refresh_elapsed := 0.0
+var _heartbeat_elapsed := 0.0
+var _remote_character_nodes: Dictionary = {}
 
 
 func _ready() -> void:
 	_tiles_root = Node3D.new()
 	_tiles_root.name = "GeneratedTiles"
 	add_child(_tiles_root)
+	_remote_players_root = Node3D.new()
+	_remote_players_root.name = "RemotePlayers"
+	add_child(_remote_players_root)
 
 	if _camera:
 		_camera_start_offset = _camera.position
@@ -75,6 +86,7 @@ func _ready() -> void:
 	_block.visible = false
 	_deactivate_player_for_load()
 	await _load_existing_locations()
+	_refresh_visible_characters()
 	_ensure_selected_location_exists(_center_coord)
 	_rebuild_tiles(_center_coord)
 	_move_player_to_coord(_center_coord)
@@ -84,6 +96,14 @@ func _ready() -> void:
 func _process(_delta: float) -> void:
 	if not _locations_loaded:
 		return
+	_visible_character_refresh_elapsed += _delta
+	_heartbeat_elapsed += _delta
+	if _visible_character_refresh_elapsed >= VISIBLE_CHARACTERS_REFRESH_INTERVAL:
+		_visible_character_refresh_elapsed = 0.0
+		_refresh_visible_characters()
+	if _heartbeat_elapsed >= HEARTBEAT_INTERVAL:
+		_heartbeat_elapsed = 0.0
+		_send_presence_heartbeat()
 	if _inventory_menu.visible:
 		return
 	var target_world_pos := _get_stream_position()
@@ -899,7 +919,7 @@ func _selected_location_name(coord: Vector2i) -> String:
 	return "Location %d,%d" % [coord.x, coord.y]
 
 
-func _load_existing_locations() -> void:
+func _load_existing_locations() -> void:
 	_locations_refresh_in_flight = true
 	_locations_loaded = false
 	_known_locations.clear()
@@ -974,9 +994,10 @@ func _load_existing_locations() -> void:
 	_locations_loaded = true
 	_locations_refresh_in_flight = false
 	_rebuild_tiles(_center_coord)
-	if _queued_locations_refresh:
-		_queued_locations_refresh = false
-		_queue_locations_refresh()
+	_refresh_visible_characters()
+	if _queued_locations_refresh:
+		_queued_locations_refresh = false
+		_queue_locations_refresh()
 
 
 func _queue_locations_refresh() -> void:
@@ -1110,12 +1131,13 @@ func _sync_character_coord(coord: Vector2i) -> void:
 	_sync_character_coord_async(coord)
 
 
-func _sync_character_coord_async(coord: Vector2i) -> void:
-	var response := await CharacterService.update_character_coord(_character_id, coord)
-	if response.get("ok", false):
-		_persisted_coord = coord
-		SelectedCharacter.set_coord(coord)
-	else:
+func _sync_character_coord_async(coord: Vector2i) -> void:
+	var response := await CharacterService.update_character_coord(_character_id, coord)
+	if response.get("ok", false):
+		_persisted_coord = coord
+		SelectedCharacter.set_coord(coord)
+		_refresh_visible_characters()
+	else:
 		push_warning("Failed to persist character coord to %s,%s: status=%s error=%s body=%s" % [
 			coord.x,
 			coord.y,
@@ -1224,6 +1246,120 @@ func _fetch_location_inventory(location_id: String) -> Array:
 
 	var payload := parsed as Dictionary
 	return _parse_floor_inventory_items(payload.get("items", []))
+
+
+func _refresh_visible_characters() -> void:
+	if _visible_characters_in_flight or _character_id.is_empty():
+		return
+	_refresh_visible_characters_async()
+
+
+func _refresh_visible_characters_async() -> void:
+	_visible_characters_in_flight = true
+	var request := HTTPRequest.new()
+	add_child(request)
+
+	var headers := PackedStringArray()
+	if not AuthState.access_token.is_empty():
+		headers.append("Authorization: Bearer %s" % AuthState.access_token)
+
+	var err := request.request("%s/%s/visible-characters" % [CHARACTER_API_URL, _character_id], headers, HTTPClient.METHOD_GET)
+	if err != OK:
+		request.queue_free()
+		push_warning("Failed to request visible characters: %s" % err)
+		_visible_characters_in_flight = false
+		return
+
+	var result: Array = await request.request_completed
+	request.queue_free()
+	_visible_characters_in_flight = false
+
+	var result_code: int = result[0]
+	var response_code: int = result[1]
+	var response_body: String = result[3].get_string_from_utf8()
+	if result_code != HTTPRequest.RESULT_SUCCESS or response_code < 200 or response_code >= 300:
+		push_warning("Failed to load visible characters (%s/%s): %s" % [result_code, response_code, response_body])
+		return
+
+	var parsed: Variant = JSON.parse_string(response_body)
+	if typeof(parsed) != TYPE_ARRAY:
+		return
+
+	_apply_visible_characters(parsed as Array)
+
+
+func _apply_visible_characters(characters: Array) -> void:
+	var wanted_ids := {}
+	for character_variant in characters:
+		if typeof(character_variant) != TYPE_DICTIONARY:
+			continue
+		var character := character_variant as Dictionary
+		var character_id := String(character.get("id", "")).strip_edges()
+		if character_id.is_empty() or character_id == _character_id:
+			continue
+		wanted_ids[character_id] = true
+		_upsert_remote_character(character)
+
+	for character_id in _remote_character_nodes.keys():
+		if wanted_ids.has(character_id):
+			continue
+		var remote_node := _remote_character_nodes[character_id] as Node3D
+		if remote_node:
+			remote_node.queue_free()
+		_remote_character_nodes.erase(character_id)
+
+
+func _upsert_remote_character(character: Dictionary) -> void:
+	var character_id := String(character.get("id", "")).strip_edges()
+	var coord_value: Variant = character.get("coord", {})
+	if typeof(coord_value) != TYPE_DICTIONARY:
+		return
+	var coord_dict := coord_value as Dictionary
+	var coord := Vector2i(int(coord_dict.get("x", 0)), int(coord_dict.get("y", 0)))
+
+	var remote_root := _remote_character_nodes.get(character_id) as Node3D
+	if remote_root == null:
+		remote_root = Node3D.new()
+		remote_root.name = "RemoteCharacter_%s" % character_id
+		_remote_players_root.add_child(remote_root)
+
+		var visual := _player_visual.duplicate() as Node3D
+		visual.name = "Visual"
+		visual.visible = true
+		remote_root.add_child(visual)
+
+		var label := Label3D.new()
+		label.name = "NameLabel"
+		label.position = Vector3(0.0, 1.8, 0.0)
+		label.billboard = BaseMaterial3D.BILLBOARD_ENABLED
+		label.pixel_size = 0.01
+		label.outline_size = 10
+		remote_root.add_child(label)
+
+		_remote_character_nodes[character_id] = remote_root
+
+	remote_root.position = Vector3(coord.x * tile_size, _get_tile_surface_y(coord), coord.y * tile_size)
+	var name_label := remote_root.get_node_or_null("NameLabel") as Label3D
+	if name_label:
+		name_label.text = String(character.get("name", "Player")).strip_edges()
+
+
+func _send_presence_heartbeat() -> void:
+	if _heartbeat_in_flight or _character_id.is_empty():
+		return
+	_send_presence_heartbeat_async()
+
+
+func _send_presence_heartbeat_async() -> void:
+	_heartbeat_in_flight = true
+	var response := await CharacterService.heartbeat_character(_character_id)
+	if not response.get("ok", false):
+		push_warning("Failed to send presence heartbeat: status=%s error=%s body=%s" % [
+			response.get("status", "n/a"),
+			response.get("error", ""),
+			response.get("body", "")
+		])
+	_heartbeat_in_flight = false
 
 
 func _get_biome_material(tile: MeshInstance3D, biome_key: String) -> Material:

game/scenes/UI/character_service.gd

@@ -24,6 +24,10 @@ func update_character_coord(character_id: String, coord: Vector2i) -> Dictionary
 		}
 	})
 	return await _request(HTTPClient.METHOD_PUT, url, payload)
+
+func heartbeat_character(character_id: String) -> Dictionary:
+	var url := "%s/%s/heartbeat" % [CHARACTER_API_URL, character_id]
+	return await _request(HTTPClient.METHOD_POST, url, "")
 
 func _request(method: int, url: String, body: String = "") -> Dictionary:
 	var request := HTTPRequest.new()

microservices/CharacterApi/Controllers/CharactersController.cs

@@ -13,6 +13,7 @@ namespace CharacterApi.Controllers;
 [Route("api/[controller]")]
 public class CharactersController : ControllerBase
 {
+    private static readonly TimeSpan PresenceTimeout = TimeSpan.FromSeconds(45);
     private readonly CharacterStore _characters;
     private readonly IHttpClientFactory _httpClientFactory;
     private readonly IConfiguration _configuration;
@@ -43,6 +44,7 @@ public class CharactersController : ControllerBase
             Name = req.Name.Trim(),
             Coord = new Coord { X = 0, Y = 0 },
             VisionRadius = 3,
+            LastSeenUtc = DateTime.UtcNow,
             CreatedUtc = DateTime.UtcNow
         };
 
@@ -89,6 +91,8 @@ public class CharactersController : ControllerBase
             return Forbid();
         }
 
+        await _characters.TouchAsync(id);
+
         _logger.LogInformation(
             "Visible locations requested for character {CharacterId} at ({X},{Y}) radius {VisionRadius} by user {UserId}",
             character.Id,
@@ -164,6 +168,53 @@ public class CharactersController : ControllerBase
         }
     }
 
+    [HttpGet("{id}/visible-characters")]
+    [Authorize(Roles = "USER,SUPER")]
+    public async Task<IActionResult> VisibleCharacters(string id)
+    {
+        var userId = User.FindFirstValue(ClaimTypes.NameIdentifier);
+        if (string.IsNullOrWhiteSpace(userId))
+            return Unauthorized();
+
+        var allowAnyOwner = User.IsInRole("SUPER");
+        var character = await _characters.GetByIdAsync(id);
+        if (character is null)
+            return NotFound();
+        if (!allowAnyOwner && character.OwnerUserId != userId)
+            return Forbid();
+
+        await _characters.TouchAsync(id);
+
+        var onlineSinceUtc = DateTime.UtcNow.Subtract(PresenceTimeout);
+        var visibleCharacters = await _characters.GetVisibleOthersAsync(
+            id,
+            character.Coord.X,
+            character.Coord.Y,
+            character.VisionRadius > 0 ? character.VisionRadius : 3,
+            onlineSinceUtc);
+
+        return Ok(visibleCharacters);
+    }
+
+    [HttpPost("{id}/heartbeat")]
+    [Authorize(Roles = "USER,SUPER")]
+    public async Task<IActionResult> Heartbeat(string id)
+    {
+        var userId = User.FindFirstValue(ClaimTypes.NameIdentifier);
+        if (string.IsNullOrWhiteSpace(userId))
+            return Unauthorized();
+
+        var allowAnyOwner = User.IsInRole("SUPER");
+        var character = await _characters.GetByIdAsync(id);
+        if (character is null)
+            return NotFound();
+        if (!allowAnyOwner && character.OwnerUserId != userId)
+            return Forbid();
+
+        await _characters.TouchAsync(id);
+        return Ok(new { lastSeenUtc = DateTime.UtcNow });
+    }
+
     [HttpPut("{id}/coord")]
     [Authorize(Roles = "USER,SUPER")]
     public async Task<IActionResult> UpdateCoord(string id, [FromBody] UpdateCharacterCoordRequest req)

microservices/CharacterApi/Models/Character.cs

@@ -17,5 +17,7 @@ public class Character
 
     public int VisionRadius { get; set; } = 3;
 
+    public DateTime LastSeenUtc { get; set; } = DateTime.UtcNow;
+
     public DateTime CreatedUtc { get; set; } = DateTime.UtcNow;
 }

microservices/CharacterApi/Models/VisibleCharacter.cs

@@ -0,0 +1,12 @@
+namespace CharacterApi.Models;
+
+public class VisibleCharacter
+{
+    public string Id { get; set; } = string.Empty;
+
+    public string Name { get; set; } = string.Empty;
+
+    public Coord Coord { get; set; } = new();
+
+    public DateTime LastSeenUtc { get; set; }
+}

microservices/CharacterApi/Services/CharacterStore.cs

@@ -17,6 +17,8 @@ public class CharacterStore
 
         var ownerIndex = Builders<Character>.IndexKeys.Ascending(c => c.OwnerUserId);
         _col.Indexes.CreateOne(new CreateIndexModel<Character>(ownerIndex));
+        var coordIndex = Builders<Character>.IndexKeys.Ascending("Coord.X").Ascending("Coord.Y");
+        _col.Indexes.CreateOne(new CreateIndexModel<Character>(coordIndex));
     }
 
     public Task CreateAsync(Character character) => _col.InsertOneAsync(character);
@@ -30,11 +32,38 @@ public class CharacterStore
     public async Task<bool> UpdateCoordAsync(string id, Coord coord)
     {
         var filter = Builders<Character>.Filter.Eq(c => c.Id, id);
-        var update = Builders<Character>.Update.Set(c => c.Coord, coord);
+        var update = Builders<Character>.Update
+            .Set(c => c.Coord, coord)
+            .Set(c => c.LastSeenUtc, DateTime.UtcNow);
         var result = await _col.UpdateOneAsync(filter, update);
         return result.ModifiedCount > 0 || result.MatchedCount > 0;
     }
 
+    public async Task<bool> TouchAsync(string id)
+    {
+        var filter = Builders<Character>.Filter.Eq(c => c.Id, id);
+        var update = Builders<Character>.Update.Set(c => c.LastSeenUtc, DateTime.UtcNow);
+        var result = await _col.UpdateOneAsync(filter, update);
+        return result.ModifiedCount > 0 || result.MatchedCount > 0;
+    }
+
+    public Task<List<VisibleCharacter>> GetVisibleOthersAsync(string characterId, int x, int y, int radius, DateTime onlineSinceUtc) =>
+        _col.Find(c =>
+                c.Id != characterId &&
+                c.Coord.X >= x - radius &&
+                c.Coord.X <= x + radius &&
+                c.Coord.Y >= y - radius &&
+                c.Coord.Y <= y + radius &&
+                c.LastSeenUtc >= onlineSinceUtc)
+            .Project(c => new VisibleCharacter
+            {
+                Id = c.Id ?? string.Empty,
+                Name = c.Name,
+                Coord = c.Coord,
+                LastSeenUtc = c.LastSeenUtc
+            })
+            .ToListAsync();
+
     public async Task<bool> DeleteForOwnerAsync(string id, string ownerUserId, bool allowAnyOwner)
     {
         var filter = Builders<Character>.Filter.Eq(c => c.Id, id);