@tool
## A resource group is a set of resources in the project
## that you want to access at runtime.
@icon("resource_group.svg")
class_name ResourceGroup
extends Resource

const PathVerifier = preload("path_verifier.gd")

## The base folder for locating files in this resource group.
@export_dir var base_folder:String = ""
## Files that should be included. Can contain ant-style wildcards:
## ** - matches zero or more characters (including "/")
## * - matches zero or more characters (excluding "/")
## ? - matches one character
@export var includes:Array[String] = []

## Files which should be excluded. Is applied after the include filter.
## Can also contain ant-style wildcards.
@export var excludes:Array[String] = []

## The paths of the project that match this resource group.
@export_custom(PROPERTY_USAGE_READ_ONLY, "") var paths:Array[String] = []


## Loads all resources in this resource group and returns them.
func load_all() -> Array[Resource]:
	var result:Array[Resource] = []
	load_all_into(result)
	return result
	
## Loads all resources and stores them into the given array. Allows
## to load resources into typed arrays for better type safety. If 
## the item is not of the required type, an error will be printed and 
## the item is skipped.
func load_all_into(destination:Array):
	for path in paths:
		destination.append(load(path))

## Gets all paths of resources inside of this resource group that
## match the given include and exclude criteria
func get_matching_paths(includes:Array[String], excludes:Array[String]) -> Array[String]:
	var path_verifier = PathVerifier.new(base_folder, includes, excludes)
	return paths.filter(func(it): return path_verifier.matches(it))

## Loads all resources in this resource group that match the given
## include and exclude criteria
func load_matching(includes:Array[String], excludes:Array[String]) -> Array[Resource]:
	var result:Array[Resource] = []
	load_matching_into(result, includes, excludes)
	return result
	
	
## Loads all resources in this resource group that match the given
## include and exclude criteria and stores them into the given array.
## Allows to load resources into typed arrays for better type safety. If 
## the item is not of the required type, an error will be printed and 
## the item is skipped.
func load_matching_into(destination:Array, includes:Array[String], excludes:Array[String]):
	var matching_paths = get_matching_paths(includes, excludes)
	for path in matching_paths:
		destination.append(load(path))


## Loads all resources in this resource group in background. Returns
## a ResourceGroupBackgroundLoader object which can be used to check the
## status and collect the results. Will call the on_resource_loaded callable for each
## loaded resource.
func load_all_in_background(on_resource_loaded:Callable) -> ResourceGroupBackgroundLoader:
	return ResourceGroupBackgroundLoader.new(paths, on_resource_loaded)

## Loads all resources in this resource group that match the given
## include and exclude criteria in background. ResourceGroupBackgroundLoader object which can be used to check the
## status and collect the results. Will call the on_resource_loaded callable for each
## loaded resource.
func load_matching_in_background(includes:Array[String], excludes:Array[String], on_resource_loaded:Callable) \
		-> ResourceGroupBackgroundLoader:
	return ResourceGroupBackgroundLoader.new(get_matching_paths(includes, excludes), on_resource_loaded)
	
#### CSHARP Specifics ####	
	
# Workaround for C# interop not being able to properly convert arrays into Godot land.
func __csharp_get_matching_paths(includes:Array, excludes:Array) -> Array[String]:
	return get_matching_paths(__to_string_array(includes), __to_string_array(excludes))
	
	
# Workaround for C# interop not being able to properly convert arrays into Godot land.
func __csharp_load_matching(includes:Array, excludes:Array) -> Array[Resource]:
	return load_matching(__to_string_array(includes), __to_string_array(excludes))


# Workaround for C# interop not being able to properly convert arrays into Godot land.
func __csharp_load_matching_in_background(includes:Array, excludes:Array, on_resource_loaded:Callable) -> ResourceGroupBackgroundLoader:
	return load_matching_in_background(__to_string_array(includes), __to_string_array(excludes), on_resource_loaded)


# Converts an untyped array to a string array.
func __to_string_array(array:Array) -> Array[String]:
	var result:Array[String] = []
	for item in array:
		result.append(item)
		
	return result