<?php

/*
 *
 *  ____            _        _   __  __ _                  __  __ ____
 * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
 * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
 * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
 * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * @author PocketMine Team
 * @link http://www.pocketmine.net/
 *
 *
*/

declare(strict_types=1);

namespace pocketmine\permission;

class PermissionParser{

	/**
	 * @param bool|string $value
	 *
	 * @return string
	 *
	 * @throws \InvalidArgumentException
	 */
	public static function defaultFromString($value) : string{
		if(is_bool($value)){
			if($value){
				return "true";
			}else{
				return "false";
			}
		}
		switch(strtolower($value)){
			case "op":
			case "isop":
			case "operator":
			case "isoperator":
			case "admin":
			case "isadmin":
				return Permission::DEFAULT_OP;

			case "!op":
			case "notop":
			case "!operator":
			case "notoperator":
			case "!admin":
			case "notadmin":
				return Permission::DEFAULT_NOT_OP;

			case "true":
				return Permission::DEFAULT_TRUE;
			case "false":
				return Permission::DEFAULT_FALSE;
		}

		throw new \InvalidArgumentException("Unknown permission default name \"$value\"");
	}

	/**
	 * @param array  $data
	 * @param string $default
	 *
	 * @return Permission[]
	 */
	public static function loadPermissions(array $data, string $default = Permission::DEFAULT_OP) : array{
		$result = [];
		foreach($data as $key => $entry){
			$result[] = self::loadPermission($key, $entry, $default, $result);
		}

		return $result;
	}

	/**
	 * @param string $name
	 * @param array  $data
	 * @param string $default
	 * @param array  $output
	 *
	 * @return Permission
	 *
	 * @throws \Exception
	 */
	public static function loadPermission(string $name, array $data, string $default = Permission::DEFAULT_OP, array &$output = []) : Permission{
		$desc = null;
		$children = [];
		if(isset($data["default"])){
			$value = PermissionParser::defaultFromString($data["default"]);
			if($value !== null){
				$default = $value;
			}else{
				throw new \InvalidStateException("'default' key contained unknown value");
			}
		}

		if(isset($data["children"])){
			if(is_array($data["children"])){
				foreach($data["children"] as $k => $v){
					if(is_array($v)){
						if(($perm = self::loadPermission($k, $v, $default, $output)) !== null){
							$output[] = $perm;
						}
					}
					$children[$k] = true;
				}
			}else{
				throw new \InvalidStateException("'children' key is of wrong type");
			}
		}

		if(isset($data["description"])){
			$desc = $data["description"];
		}

		return new Permission($name, $desc, $default, $children);
	}

	/**
	 * @param Permission[] $permissions
	 *
	 * @return array
	 */
	public static function emitPermissions(array $permissions) : array{
		$result = [];
		foreach($permissions as $permission){
			$result[$permission->getName()] = self::emitPermission($permission);
		}
		ksort($result);
		return $result;
	}

	private static function emitPermission(Permission $permission) : array{
		$result = [
			"description" => $permission->getDescription(),
			"default" => $permission->getDefault()
		];
		$children = [];
		foreach($permission->getChildren() as $name => $bool){
			//TODO: really? wtf??? this system is so overengineered it makes my head hurt...
			$child = PermissionManager::getInstance()->getPermission($name);
			if($child === null){
				throw new \UnexpectedValueException("Permission child should be a registered permission");
			}
			$children[$name] = self::emitPermission($child);
		}
		if(!empty($children)){
			ksort($children);
			$result["children"] = $children;
		}
		return $result;
	}
}