Major clean up and reorganization

- Upgraded to Godot 4
- Just remembered the basic principles are based on a tile editor, and dramatically simplified from there. Derp.
- New state machine and license display add-ons.
- Re-licensed under the GPL because Micropolis' assets aren't under a separate one.

addons/simplelicense/api/LicenseManager.gd

@@ -0,0 +1,121 @@
+class_name LicenseManager
+extends Node
+
+## loads license information from this directory and the sub-directory "license_links"
+@export var load_dir: String = "res://licenses"
+
+## export license information to this directory and the sub-directory "licenses"
+@export var export_dir: String = "user://"
+
+## This disables loading Godot's built-in license information [br]
+## this is for mods, in which the main game will have already shown the Godot's built-in Licensing
+@export var exclude_engine: bool = false
+
+## contains all loaded [License]s [br]
+## key = identifier [br]
+## value = [License]
+var licenses := {} 
+
+## contains all loaded [LicenseLink]s [br]
+## with searching in mind [br]
+## "array" [] [br]
+## "by_identifier" {} license identifier [br]
+## "by_parent" {} parent component name [br]
+var license_links := {
+	'array': [],
+	'by_identifier': {},
+	'by_parent': {},
+}
+
+
+## Loads license information from [member load_dir] [br]
+func load_license_information():
+	licenses.clear()
+	license_links.array.clear()
+	license_links.by_identifier.clear()
+	license_links.by_parent.clear()
+	
+	if not DirAccess.dir_exists_absolute(load_dir):
+		printerr("Failed to find license directory ", load_dir)
+		return
+	
+	licenses = License._load_licenses_in(load_dir)
+	if licenses.has('Expat') and not licenses.has('MIT'):
+		var l = licenses['Expat'].duplicate() as License
+		l.identifier = 'MIT'
+		licenses['MIT'] = l
+	
+	license_links = LicenseLink._load_links_in(load_dir.path_join('license_links'), exclude_engine)
+
+
+## Returns a single string "file", that is formatted in the SPDX Standard [br]
+## that contains all licensing information, contained in this instance, [br]
+## if only_links, then the returned data will omit the licensing term files
+func get_combined_copyright(only_links: bool = false) -> String:
+	var lines = ""
+	
+	var used_licenses = {}
+	
+	# Links
+	for link in license_links.array:
+		if link is LicenseLink:
+			lines += link.to_formatted_string(link.component_of == 'Godot Engine')
+			lines += '\n'
+			used_licenses.merge(get_all_valid_licenses(link))
+	
+	lines += '\n\n'
+	
+	if only_links:
+		return lines
+	
+	# License Terms
+	var values = used_licenses.values()
+	for i in len(values):
+		if i+1 < len(values):
+			lines += values[i].to_formatted_string() + '\n'
+		else:
+			lines += values[i].to_formatted_string()
+
+	return lines
+
+## Returns all licenses that are "valid"/exist [br]
+## Sometimes license files are missing, or Identifiers are incorrectly spelled, this helps with that.
+func get_all_valid_licenses(link: LicenseLink) -> Dictionary:
+	var d = {}
+	for x in link.license_identifiers:
+		if licenses.has(x):
+			d[x] = licenses[x]
+	return d
+
+## export all license information to [member export_dir] and the sub-directory "licenses"
+func export(directory: String = ""):
+	if directory.is_empty():
+		directory = export_dir
+	
+	var licenses_path = directory.path_join('licenses')
+	if not DirAccess.dir_exists_absolute(licenses_path):
+		DirAccess.make_dir_recursive_absolute(licenses_path)
+	
+	# Export the combined license file
+	var f = FileAccess.open(directory.path_join('COPYRIGHT.txt'), FileAccess.WRITE)
+	if f is FileAccess:
+		f.store_string(self.get_combined_copyright())
+	
+	# Export the slim license file
+	f = FileAccess.open(directory.path_join('COPYRIGHT_SLIM.txt'), FileAccess.WRITE)
+	if f is FileAccess:
+		f.store_string(self.get_combined_copyright(true))
+	
+	
+	# Export the individual license files
+	
+	var used = {}
+	for i in license_links.array.size():
+		var license = license_links.array[i] as LicenseLink
+		var ids = self.get_all_valid_licenses(license)
+		used.merge(ids)
+		
+		for id in ids:
+			var license_path = licenses_path.path_join(id)+'.txt'
+			f = FileAccess.open(license_path, FileAccess.WRITE)
+			f.store_string(licenses[id].to_formatted_string())