class_name EnemyDefinitions
extends RefCounted

const DEFAULT_ID: String = "chaser"
const ORDER: PackedStringArray = ["chaser", "sniper", "artillery", "turret_spawner", "enemy_mothership"]
const DEFINITIONS: Dictionary = {
	"chaser": preload("res://enemies/ChaserEnemyDefinition.tres"),
	"sniper": preload("res://enemies/SniperEnemyDefinition.tres"),
	"artillery": preload("res://enemies/ArtilleryEnemyDefinition.tres"),
	"turret_spawner": preload("res://enemies/TurretSpawnerEnemyDefinition.tres"),
	"enemy_mothership": preload("res://enemies/MothershipEnemyDefinition.tres"),
}


# The single place that knows what an enemy LOOKS like. Three things draw
# enemies - the enemy itself, the map editor's markers, and the editor's
# palette buttons - and each used to reimplement it from hull_points alone.
# Adding interior detail to the definitions therefore showed up in the game
# and nowhere else, so an editor marker no longer matched the ship it placed.
#
# `at` and `scale` exist because the palette draws into a small button
# centred on itself, while the other two draw around their own origin at
# full size.
static func draw_definition(item: CanvasItem, definition: Resource, glow: Color,
		scale: float = 1.0, at: Vector2 = Vector2.ZERO) -> void:
	if definition == null:
		return
	var core: Color = definition.core_color
	item.draw_set_transform(at, 0.0, Vector2(scale, scale))
	NeonDraw.draw_glowing_polygon(item, definition.hull_points, glow, 1.0, core)
	var lines: PackedVector2Array = definition.detail_lines
	for i in range(0, lines.size() - 1, 2):
		NeonDraw.draw_glowing_line(item, lines[i], lines[i + 1], glow, 0.85, 0.55, core)
	var rings: PackedVector2Array = definition.detail_rings
	for i in range(0, rings.size() - 1, 2):
		NeonDraw.draw_glowing_circle(item, rings[i], rings[i + 1].x, glow, 0.85, core)
	item.draw_set_transform(Vector2.ZERO, 0.0, Vector2.ONE)


static func get_definition(enemy_id: String) -> Resource:
	return DEFINITIONS.get(enemy_id, DEFINITIONS[DEFAULT_ID])


static func all() -> Array:
	var result: Array = []
	for enemy_id in ORDER:
		result.append(DEFINITIONS[enemy_id])
	return result