@tool
extends Object
class_name AssetLoader

#region Declaration ---
# === CONST ===

const DEFAULT_ASSETS_PATH = "res://mods"

## If you want to change the mod extension. Keep in mind that it's still a json under the hood
const MOD_INFOS_EXTENSION = "modinfo"

## Path to the mods folder : [param res://mods] by default
## [br]
## (is not a const but should be treated as such, so the uppercase)
var ASSETS_PATH

# === VAR ===
var dir:DirAccess
var mod_folders:PackedStringArray
var critical_error := false

var mod_paths : PackedStringArray
var mod_manifests : Dictionary[String,ModManifest]

# === SIGNALS ===
signal loading_finished

#endregion ---


func _init() -> void:
	print_verbose("------ MOD LOADING STARTED ------")
	ASSETS_PATH = ProjectSettings.get_setting("game/mods/mod_path", DEFAULT_ASSETS_PATH)
	dir = DirAccess.open(ASSETS_PATH)
	if not dir:
		push_error("AssetLoader: Mods folder not found at '%s'" % ASSETS_PATH)
		push_error("AssetLoader:",DirAccess.get_open_error())
		_show_error_popup("Mods folder not found at '%s'" % ASSETS_PATH)
		critical_error = true
		return
	mod_folders = dir.get_directories()
	if mod_folders.is_empty():
		push_error("AssetLoader: Mods folder '%s' is empty — no mods to load." % ASSETS_PATH)
		_show_error_popup("Mods folder '%s' is empty — no mods to load." % ASSETS_PATH)
		critical_error = true
		return

# === PRIVATE ===


## This will show a native MessageBox on Windows,
## a native dialog on macOS, and GTK/QT dialog on Linux.
func _show_error_popup(message: String) -> void:
	OS.alert("AssetLoader:"+message, "AssetLoader:Error")


# === PUBLIC ===
func load_all():
	load_mods()
	load_mods_content()


## Load and unpack all .pck before serialization
func load_mods():
	for mod in mod_folders:
		var mod_name = mod
		var mod_path = ASSETS_PATH + "/" + mod_name
		var manifest_path = mod_path + "/" + mod_name + "." + MOD_INFOS_EXTENSION
		if FileAccess.file_exists(manifest_path):
			var manifest_file := FileAccess.open(manifest_path, FileAccess.READ)
			var manifest: ModManifest = ModManifest.new_from_file(manifest_file)
			if !manifest:continue
			if !mod_manifests.has(manifest.id):
				mod_manifests[manifest.id] = manifest
				print_verbose("Mod manifest is loaded: %s" % manifest.name)
				var modpacks:Array = manifest.get_mod_packs()
				if manifest.packs.size() > 0:
					for pack in manifest.packs:
						if dir.file_exists(ASSETS_PATH + "/" + mod_name + pack + ".pck"): # variable re-usage here
							pass
						modpacks.append(pack)
			else:
				push_warning("Another mod as the same id:\n %s will not be loaded" % manifest_path)

		else:
			push_warning("No manifest found in %s" % manifest_path)
	for mod in mod_manifests:
		print("Mod loaded: %s" % mod)





func load_mods_content():
	pass