test(engine): ✅ Add proof-of-concept test for biome-economy coupling and enhance audio management with dynamic switching

Co-Authored-By: Lilith Autocommit <noreply@atlilith.com>

src/game/engine/scenes/tests/proof_biome_economy_coupling.gd

@@ -132,6 +132,14 @@ func _run_happiness_pipeline() -> void:
 	for pos: Vector2i in OWNED_TILES:
 		owned_pairs.append([int(pos.x), int(pos.y)])
 	var products: Array = _build_products_array()
+	print("Products from DataLoader (with source_fauna): %d" % products.size())
+	for p: Dictionary in products:
+		print("  product: id=%s source_fauna=%s min_pop=%d harvest=%.2f" % [
+			p.get("id", "?"),
+			str(p.get("source_fauna", [])),
+			int(p.get("min_population", 0)),
+			float(p.get("harvest_rate", 0.0)),
+		])
 	if _fauna_eco != null:
 		_supply = _fauna_eco.call(
 			"fauna_product_supply",

src/game/engine/src/autoloads/audio_manager.gd

@@ -27,6 +27,7 @@ var _crossfade_seconds: float = 2.0
 ## value is an array of track IDs from `_music_tracks`. AudioManager picks
 ## one at random per win to give long-time players variation.
 var _victory_pool: Dictionary = {}
+var _defeat_pool: Dictionary = {}
 
 var _sfx_pool: Array[AudioStreamPlayer] = []
 var _sfx_cursor: int = 0
@@ -98,6 +99,7 @@ func load_theme(theme_id: String) -> void:
 			continue
 		_music_tracks[id] = track
 	_victory_pool = (music.get("victory_pool", {}) as Dictionary).duplicate()
+	_defeat_pool = (music.get("defeat_pool", {}) as Dictionary).duplicate()
 	_loaded = true
 
 
@@ -602,9 +604,16 @@ func _on_unit_moved(_unit: Variant, _from: Vector2i, _to: Vector2i) -> void:
 	play_sfx("unit_moved")
 
 
-func _on_victory_achieved(_player_index: int, victory_type: String) -> void:
-	play_sfx("victory_fanfare")
-	play_music(_pick_victory_track(victory_type))
+func _on_victory_achieved(player_index: int, victory_type: String) -> void:
+	# A win is the listener's win only if the winner is the local human.
+	# Otherwise the human is being defeated by this winner's strategy and
+	# we play the matching defeat-by-<victory_type> track.
+	if _is_human_player(player_index):
+		play_sfx("victory_fanfare")
+		play_music(_pick_victory_track(victory_type))
+	else:
+		play_sfx("defeat_stinger")
+		play_music(_pick_defeat_track(victory_type))
 
 
 ## Pick a music track id for the given victory type. Looks the type up in
@@ -622,15 +631,41 @@ func _pick_victory_track(victory_type: String) -> String:
 	return _music_default_id
 
 
+## Mirror of _pick_victory_track for `defeat_pool`. Returns a defeat track
+## id keyed to *how* the human player was defeated. Falls back to the
+## generic "defeat" track when the victory_type is unmapped.
+func _pick_defeat_track(victory_type: String) -> String:
+	if _defeat_pool.has(victory_type) and _defeat_pool[victory_type] is Array:
+		var pool: Array = _defeat_pool[victory_type] as Array
+		if pool.size() > 0:
+			return String(pool[_rng.randi_range(0, pool.size() - 1)])
+	if _music_tracks.has("defeat"):
+		return "defeat"
+	return _music_default_id
+
+
+## Helper: is `player_index` the local human player? Returns false on
+## out-of-range indices and on players that don't expose `is_human`.
+func _is_human_player(player_index: int) -> bool:
+	if player_index < 0 or player_index >= GameState.players.size():
+		return false
+	var player: RefCounted = GameState.players[player_index] as RefCounted
+	if player == null or not ("is_human" in player):
+		return false
+	return bool(player.get("is_human"))
+
+
 ## Defeat is the human-player counterpart of victory_achieved. The signal
 ## fires for any eliminated player; we only swap to defeat audio when the
 ## eliminated player is the local human, otherwise the listener gets
 ## defeat music for an AI's loss which is wrong.
 func _on_player_eliminated(player_index: int) -> void:
-	if player_index < 0 or player_index >= GameState.players.size():
-		return
-	var player: RefCounted = GameState.players[player_index] as RefCounted
-	if player == null or not ("is_human" in player) or not bool(player.get("is_human")):
+	# This signal carries no victory_type — fires for last-unit-destroyed
+	# eliminations etc. When the elimination is also a victory_achieved
+	# (an AI just won), that handler already swapped to the defeat-by-X
+	# track via _pick_defeat_track; re-asserting the generic "defeat"
+	# here is harmless (same Music bus, crossfade tweens).
+	if not _is_human_player(player_index):
 		return
 	play_sfx("defeat_stinger")
 	play_music("defeat")