From 510d14fd4caadcacfa023ff73d7b2abefb14be48 Mon Sep 17 00:00:00 2001
From: Stefano Pigozzi <me@steffo.eu>
Date: Sun, 14 Apr 2024 21:21:43 +0200
Subject: [PATCH] Create `SpawnerChoice` selecting a random subspawner to spawn
 things from

---
 behaviours/spawner_choice.gd   | 34 ++++++++++++++++++++++++++++++++++
 behaviours/spawner_choice.tscn |  3 +++
 2 files changed, 37 insertions(+)
 create mode 100644 behaviours/spawner_choice.gd
 create mode 100644 behaviours/spawner_choice.tscn

diff --git a/behaviours/spawner_choice.gd b/behaviours/spawner_choice.gd
new file mode 100644
index 0000000..71def18
--- /dev/null
+++ b/behaviours/spawner_choice.gd
@@ -0,0 +1,34 @@
+extends Node
+class_name SpawnerChoice
+
+
+@export var spawners: Array[Spawner] = []
+@export var weights: Array[int] = []
+
+
+func compute_total_weight() -> int:
+	var total = 0
+	for weight in weights:
+		if weight < 0:
+			Log.e(self, "Weight with negative value detected.")
+		total += weight
+	return total
+
+func select_spawner() -> Spawner:
+	var total = compute_total_weight()
+	var sampled = Random.rng.randi_range(0, total - 1)
+	var idx = -1
+	while sampled >= 0:
+		idx += 1
+		sampled -= weights[idx]
+	return spawners[idx]
+
+func spawn():
+	select_spawner().spawn()
+
+
+func _ready():
+	if len(spawners) != len(weights):
+		Log.e(self, "Spawners and weights are different lengths.")
+	if compute_total_weight() <= 0:
+		Log.e(self, "Weight total is less or equal to 0.")
diff --git a/behaviours/spawner_choice.tscn b/behaviours/spawner_choice.tscn
new file mode 100644
index 0000000..27deaaf
--- /dev/null
+++ b/behaviours/spawner_choice.tscn
@@ -0,0 +1,3 @@
+[gd_scene format=3 uid="uid://cokdfsk6rgeup"]
+
+[node name="SpawnerChoice" type="Node"]