From 2376325417b6a231c157b847444547f5ee0704d7 Mon Sep 17 00:00:00 2001
From: Justin Spahr-Summers <justin@jspahrsummers.com>
Date: Sun, 14 Jul 2024 00:06:07 +0100
Subject: [PATCH] Abstract out array cycling logic

@skip-notify
---
 actors/player.gd     | 46 ++++++++------------------------------------
 project.godot        |  1 +
 utils/array_utils.gd | 14 ++++++++++++++
 3 files changed, 23 insertions(+), 38 deletions(-)
 create mode 100644 utils/array_utils.gd

diff --git a/actors/player.gd b/actors/player.gd
index 4e1d07e4..b1ebb0f3 100644
--- a/actors/player.gd
+++ b/actors/player.gd
@@ -94,35 +94,18 @@ func _on_jump_destination_loaded(_system: StarSystem) -> void:
     self.ship.position = MathUtils.random_unit_vector() * HYPERSPACE_ARRIVAL_RADIUS
     self.ship.targeting_system.target = null
 
-## Cycles through systems connected to this one, for picking a hyperspace jump destination.
 func _next_system_connection() -> StarSystem:
-    var connections := self.hyperspace_controller.current_system.connections
-    if connections.size() == 0:
-        return null
+    var current_destination_name: Variant = null
+    if self.hyperspace_controller.jump_destination:
+        current_destination_name = self.hyperspace_controller.jump_destination.name
 
-    if self.hyperspace_controller.jump_destination == null:
-        return self.hyperspace_controller.galaxy.get_system(connections[0])
+    var next_destination_name: Variant = ArrayUtils.cycle_through(self.hyperspace_controller.current_system.connections, current_destination_name)
+    return self.hyperspace_controller.galaxy.get_system(next_destination_name as StringName) if next_destination_name else null
 
-    var index := connections.find(self.hyperspace_controller.jump_destination.name)
-    assert(index >= 0, "Cannot find jump destination in system connections")
-
-    return self.hyperspace_controller.galaxy.get_system(connections[index + 1]) if index + 1 < connections.size() else null
-
-## Cycles through targets in the current system.
 func _next_target() -> CombatObject:
     var available_targets := self.ship.targeting_system.get_available_targets()
     available_targets.erase(self.ship.combat_object)
-    if available_targets.size() == 0:
-        return null
-    
-    var target := self.ship.targeting_system.target
-    if target == null:
-        return available_targets[0]
-    
-    var index := available_targets.find(target)
-    assert(index >= 0, "Cannot find currently targeted object")
-
-    return available_targets[index + 1] if index + 1 < available_targets.size() else null
+    return ArrayUtils.cycle_through(available_targets, self.ship.targeting_system.target)
 
 func _available_landing_targets() -> Array[PlanetInstance]:
     var targets: Array[PlanetInstance] = []
@@ -144,20 +127,6 @@ func _closest_landing_target() -> PlanetInstance:
     
     return nearest_planet_instance
 
-func _next_landing_target() -> PlanetInstance:
-    var available_targets := self._available_landing_targets()
-    if available_targets.size() == 0:
-        return null
-
-    var target := self.landing_target
-    if target == null:
-        return available_targets[0]
-    
-    var index := available_targets.find(target)
-    assert(index >= 0, "Cannot find currently targeted object")
-
-    return available_targets[index + 1] if index + 1 < available_targets.size() else null
-
 func _unhandled_key_input(event: InputEvent) -> void:
     if self.hyperspace_controller.jumping:
         return
@@ -177,7 +146,8 @@ func _unhandled_key_input(event: InputEvent) -> void:
         self._land()
 
     if event.is_action_pressed("cycle_landing_target", true):
-        self.landing_target = self._next_landing_target()
+        var next_target: PlanetInstance = ArrayUtils.cycle_through(self._available_landing_targets(), self.landing_target)
+        self.landing_target = next_target
         self.get_viewport().set_input_as_handled()
 
 func _jump_to_hyperspace() -> void:
diff --git a/project.godot b/project.godot
index 20b303cf..02fe3fa0 100644
--- a/project.godot
+++ b/project.godot
@@ -23,6 +23,7 @@ config/icon="res://screens/shared_ui/images/icon.png"
 
 UserPreferences="*res://utils/user_preferences.gd"
 MathUtils="*res://utils/math_utils.gd"
+ArrayUtils="*res://utils/array_utils.gd"
 
 [debug]
 
diff --git a/utils/array_utils.gd b/utils/array_utils.gd
new file mode 100644
index 00000000..400dc9d8
--- /dev/null
+++ b/utils/array_utils.gd
@@ -0,0 +1,14 @@
+extends Node
+
+## Finds the next object in [param array] after [param starting_from], wrapping around to `null` if the end of the array is reached.
+func cycle_through(array: Array, starting_from: Variant) -> Variant:
+    if array.size() == 0:
+        return null
+    
+    if starting_from == null:
+        return array[0]
+    
+    var index := array.find(starting_from)
+    assert(index >= 0, "Cannot find starting_from in array")
+
+    return array[index + 1] if index + 1 < array.size() else null