Improve composer definition

Author: nyamsprod

README.md

@@ -36,10 +36,14 @@ composer require jeremykendall/php-domain-parser:^6.0
 
 You need:
 
-- **PHP >= 7.4** but the latest stable version of PHP is recommended
-- the `intl` extension
+- **PHP >= 8.1** but the latest stable version of PHP is recommended
 - a copy of the [Public Suffix List](https://publicsuffix.org/) data and/or a copy of the [IANA Top Level Domain List](https://www.iana.org/domains/root/files). Please refer to the [Managing external data source section](#managing-the-package-external-resources) for more information when using this package in production.
 
+Handling of an IDN host requires the presence of the `intl` extension or
+a polyfill for the `intl` IDN functions like the `symfony/polyfill-intl-idn`
+otherwise an exception will be thrown when attempting to validate or interact
+with such a host.
+
 ## Usage
 
 > [!WARNING]

composer.json

@@ -41,8 +41,7 @@
     ],
     "require": {
         "php": "^8.1",
-        "ext-filter": "*",
-        "ext-intl": "*"
+        "ext-filter": "*"
     },
     "require-dev": {
         "friendsofphp/php-cs-fixer": "^3.65.0",
@@ -61,7 +60,9 @@
         "psr/http-client-implementation": "To use the storage functionality which depends on PSR-18",
         "psr/http-factory-implementation": "To use the storage functionality which depends on PSR-17",
         "psr/simple-cache-implementation": "To use the storage functionality which depends on PSR-16",
-        "league/uri": "To parse URL and validate host"
+        "league/uri": "To parse and extract the host from an URL using a RFC3986/RFC3987 URI parser",
+        "rowbot/url": "To parse and extract the host from an URL using a  WHATWG URL parser",
+        "symfony/polyfill-intl-idn": "to handle IDN host via the Symfony polyfill if ext-intl is not present"
     },
     "autoload": {
         "psr-4": {