<?php

/**
 * This file is part of the CodeIgniter 4 framework.
 *
 * (c) CodeIgniter Foundation <admin@codeigniter.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace CodeIgniter\Router;

use Closure;
use CodeIgniter\Autoloader\FileLocator;
use CodeIgniter\HTTP\Request;
use CodeIgniter\Router\Exceptions\RouterException;
use Config\Modules;
use Config\Services;
use InvalidArgumentException;

/**
 * Class RouteCollection
 *
 * @todo Implement nested resource routing (See CakePHP)
 */
class RouteCollection implements RouteCollectionInterface
{
	/**
	 * The namespace to be added to any Controllers.
	 * Defaults to the global namespaces (\)
	 *
	 * @var string
	 */
	protected $defaultNamespace = '\\';

	/**
	 * The name of the default controller to use
	 * when no other controller is specified.
	 *
	 * Not used here. Pass-thru value for Router class.
	 *
	 * @var string
	 */
	protected $defaultController = 'Home';

	/**
	 * The name of the default method to use
	 * when no other method has been specified.
	 *
	 * Not used here. Pass-thru value for Router class.
	 *
	 * @var string
	 */
	protected $defaultMethod = 'index';

	/**
	 * The placeholder used when routing 'resources'
	 * when no other placeholder has been specified.
	 *
	 * @var string
	 */
	protected $defaultPlaceholder = 'any';

	/**
	 * Whether to convert dashes to underscores in URI.
	 *
	 * Not used here. Pass-thru value for Router class.
	 *
	 * @var boolean
	 */
	protected $translateURIDashes = false;

	/**
	 * Whether to match URI against Controllers
	 * when it doesn't match defined routes.
	 *
	 * Not used here. Pass-thru value for Router class.
	 *
	 * @var boolean
	 */
	protected $autoRoute = true;

	/**
	 * A callable that will be shown
	 * when the route cannot be matched.
	 *
	 * @var string|Closure
	 */
	protected $override404;

	/**
	 * Defined placeholders that can be used
	 * within the
	 *
	 * @var array
	 */
	protected $placeholders = [
		'any'      => '.*',
		'segment'  => '[^/]+',
		'alphanum' => '[a-zA-Z0-9]+',
		'num'      => '[0-9]+',
		'alpha'    => '[a-zA-Z]+',
		'hash'     => '[^/]+',
	];

	/**
	 * An array of all routes and their mappings.
	 *
	 * @var array
	 */
	protected $routes = [
		'*'       => [],
		'options' => [],
		'get'     => [],
		'head'    => [],
		'post'    => [],
		'put'     => [],
		'delete'  => [],
		'trace'   => [],
		'connect' => [],
		'cli'     => [],
	];

	/**
	 * Array of routes options
	 *
	 * @var array
	 */
	protected $routesOptions = [];

	/**
	 * The current method that the script is being called by.
	 *
	 * @var string
	 */
	protected $HTTPVerb;

	/**
	 * The default list of HTTP methods (and CLI for command line usage)
	 * that is allowed if no other method is provided.
	 *
	 * @var array
	 */
	protected $defaultHTTPMethods = [
		'options',
		'get',
		'head',
		'post',
		'put',
		'delete',
		'trace',
		'connect',
		'cli',
	];

	/**
	 * The name of the current group, if any.
	 *
	 * @var string|null
	 */
	protected $group;

	/**
	 * The current subdomain.
	 *
	 * @var string|null
	 */
	protected $currentSubdomain;

	/**
	 * Stores copy of current options being
	 * applied during creation.
	 *
	 * @var array|null
	 */
	protected $currentOptions;

	/**
	 * A little performance booster.
	 *
	 * @var boolean
	 */
	protected $didDiscover = false;

	/**
	 * Handle to the file locator to use.
	 *
	 * @var FileLocator
	 */
	protected $fileLocator;

	/**
	 * Handle to the modules config.
	 *
	 * @var Modules
	 */
	protected $moduleConfig;

	//--------------------------------------------------------------------

	/**
	 * Constructor
	 *
	 * @param FileLocator $locator
	 * @param Modules     $moduleConfig
	 */
	public function __construct(FileLocator $locator, Modules $moduleConfig)
	{
		$this->fileLocator  = $locator;
		$this->moduleConfig = $moduleConfig;
	}

	//--------------------------------------------------------------------

	/**
	 * Registers a new constraint with the system. Constraints are used
	 * by the routes as placeholders for regular expressions to make defining
	 * the routes more human-friendly.
	 *
	 * You can pass an associative array as $placeholder, and have
	 * multiple placeholders added at once.
	 *
	 * @param string|array $placeholder
	 * @param string|null  $pattern
	 *
	 * @return RouteCollectionInterface
	 */
	public function addPlaceholder($placeholder, string $pattern = null): RouteCollectionInterface
	{
		if (! is_array($placeholder))
		{
			$placeholder = [$placeholder => $pattern];
		}

		$this->placeholders = array_merge($this->placeholders, $placeholder);

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Sets the default namespace to use for Controllers when no other
	 * namespace has been specified.
	 *
	 * @param string $value
	 *
	 * @return RouteCollectionInterface
	 */
	public function setDefaultNamespace(string $value): RouteCollectionInterface
	{
		$this->defaultNamespace = filter_var($value, FILTER_SANITIZE_STRING);
		$this->defaultNamespace = rtrim($this->defaultNamespace, '\\') . '\\';

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Sets the default controller to use when no other controller has been
	 * specified.
	 *
	 * @param string $value
	 *
	 * @return RouteCollectionInterface
	 */
	public function setDefaultController(string $value): RouteCollectionInterface
	{
		$this->defaultController = filter_var($value, FILTER_SANITIZE_STRING);

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Sets the default method to call on the controller when no other
	 * method has been set in the route.
	 *
	 * @param string $value
	 *
	 * @return RouteCollectionInterface
	 */
	public function setDefaultMethod(string $value): RouteCollectionInterface
	{
		$this->defaultMethod = filter_var($value, FILTER_SANITIZE_STRING);

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Tells the system whether to convert dashes in URI strings into
	 * underscores. In some search engines, including Google, dashes
	 * create more meaning and make it easier for the search engine to
	 * find words and meaning in the URI for better SEO. But it
	 * doesn't work well with PHP method names....
	 *
	 * @param boolean $value
	 *
	 * @return RouteCollectionInterface
	 */
	public function setTranslateURIDashes(bool $value): RouteCollectionInterface
	{
		$this->translateURIDashes = $value;

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * If TRUE, the system will attempt to match the URI against
	 * Controllers by matching each segment against folders/files
	 * in APPPATH/Controllers, when a match wasn't found against
	 * defined routes.
	 *
	 * If FALSE, will stop searching and do NO automatic routing.
	 *
	 * @param boolean $value
	 *
	 * @return RouteCollectionInterface
	 */
	public function setAutoRoute(bool $value): RouteCollectionInterface
	{
		$this->autoRoute = $value;

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Sets the class/method that should be called if routing doesn't
	 * find a match. It can be either a closure or the controller/method
	 * name exactly like a route is defined: Users::index
	 *
	 * This setting is passed to the Router class and handled there.
	 *
	 * @param callable|null $callable
	 *
	 * @return RouteCollectionInterface
	 */
	public function set404Override($callable = null): RouteCollectionInterface
	{
		$this->override404 = $callable;

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Returns the 404 Override setting, which can be null, a closure
	 * or the controller/string.
	 *
	 * @return string|Closure|null
	 */
	public function get404Override()
	{
		return $this->override404;
	}

	//--------------------------------------------------------------------

	/**
	 * Will attempt to discover any additional routes, either through
	 * the local PSR4 namespaces, or through selected Composer packages.
	 */
	protected function discoverRoutes()
	{
		if ($this->didDiscover)
		{
			return;
		}

		// We need this var in local scope
		// so route files can access it.
		$routes = $this;

		if ($this->moduleConfig->shouldDiscover('routes'))
		{
			$files = $this->fileLocator->search('Config/Routes.php');

			foreach ($files as $file)
			{
				// Don't include our main file again...
				if ($file === APPPATH . 'Config/Routes.php')
				{
					continue;
				}

				include $file;
			}
		}

		$this->didDiscover = true;
	}

	//--------------------------------------------------------------------

	/**
	 * Sets the default constraint to be used in the system. Typically
	 * for use with the 'resource' method.
	 *
	 * @param string $placeholder
	 *
	 * @return RouteCollectionInterface
	 */
	public function setDefaultConstraint(string $placeholder): RouteCollectionInterface
	{
		if (array_key_exists($placeholder, $this->placeholders))
		{
			$this->defaultPlaceholder = $placeholder;
		}

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Returns the name of the default controller. With Namespace.
	 *
	 * @return string
	 */
	public function getDefaultController(): string
	{
		return $this->defaultController;
	}

	//--------------------------------------------------------------------

	/**
	 * Returns the name of the default method to use within the controller.
	 *
	 * @return string
	 */
	public function getDefaultMethod(): string
	{
		return $this->defaultMethod;
	}

	//--------------------------------------------------------------------

	/**
	 * Returns the default namespace as set in the Routes config file.
	 *
	 * @return string
	 */
	public function getDefaultNamespace(): string
	{
		return $this->defaultNamespace;
	}

	//--------------------------------------------------------------------

	/**
	 * Returns the current value of the translateURIDashes setting.
	 *
	 * @return boolean
	 */
	public function shouldTranslateURIDashes(): bool
	{
		return $this->translateURIDashes;
	}

	//--------------------------------------------------------------------

	/**
	 * Returns the flag that tells whether to autoRoute URI against Controllers.
	 *
	 * @return boolean
	 */
	public function shouldAutoRoute(): bool
	{
		return $this->autoRoute;
	}

	//--------------------------------------------------------------------

	/**
	 * Returns the raw array of available routes.
	 *
	 * @param string|null $verb
	 *
	 * @return array
	 */
	public function getRoutes(string $verb = null): array
	{
		if (empty($verb))
		{
			$verb = $this->getHTTPVerb();
		}

		// Since this is the entry point for the Router,
		// take a moment to do any route discovery
		// we might need to do.
		$this->discoverRoutes();

		$routes     = [];
		$collection = [];

		if (isset($this->routes[$verb]))
		{
			// Keep current verb's routes at the beginning so they're matched
			// before any of the generic, "add" routes.
			if (isset($this->routes['*']))
			{
				$extraRules = array_diff_key($this->routes['*'], $this->routes[$verb]);
				$collection = array_merge($this->routes[$verb], $extraRules);
			}
			foreach ($collection as $r)
			{
				$key          = key($r['route']);
				$routes[$key] = $r['route'][$key];
			}
		}

		return $routes;
	}

	//--------------------------------------------------------------------

	/**
	 * Returns one or all routes options
	 *
	 * @param string|null $from
	 * @param string|null $verb
	 *
	 * @return array
	 */
	public function getRoutesOptions(string $from = null, string $verb = null): array
	{
		$options = $this->loadRoutesOptions($verb);

		return $from ? $options[$from] ?? [] : $options;
	}

	//--------------------------------------------------------------------

	/**
	 * Returns the current HTTP Verb being used.
	 *
	 * @return string
	 */
	public function getHTTPVerb(): string
	{
		return $this->HTTPVerb;
	}

	//--------------------------------------------------------------------

	/**
	 * Sets the current HTTP verb.
	 * Used primarily for testing.
	 *
	 * @param string $verb
	 *
	 * @return $this
	 */
	public function setHTTPVerb(string $verb)
	{
		$this->HTTPVerb = $verb;

		return $this;
	}

	/**
	 * A shortcut method to add a number of routes at a single time.
	 * It does not allow any options to be set on the route, or to
	 * define the method used.
	 *
	 * @param array      $routes
	 * @param array|null $options
	 *
	 * @return RouteCollectionInterface
	 */
	public function map(array $routes = [], array $options = null): RouteCollectionInterface
	{
		foreach ($routes as $from => $to)
		{
			$this->add($from, $to, $options);
		}

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Adds a single route to the collection.
	 *
	 * Example:
	 *      $routes->add('news', 'Posts::index');
	 *
	 * @param string       $from
	 * @param array|string $to
	 * @param array|null   $options
	 *
	 * @return RouteCollectionInterface
	 */
	public function add(string $from, $to, array $options = null): RouteCollectionInterface
	{
		$this->create('*', $from, $to, $options);

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Adds a temporary redirect from one route to another. Used for
	 * redirecting traffic from old, non-existing routes to the new
	 * moved routes.
	 *
	 * @param string  $from   The pattern to match against
	 * @param string  $to     Either a route name or a URI to redirect to
	 * @param integer $status The HTTP status code that should be returned with this redirect
	 *
	 * @return RouteCollection
	 */
	public function addRedirect(string $from, string $to, int $status = 302)
	{
		// Use the named route's pattern if this is a named route.
		if (array_key_exists($to, $this->routes['*']))
		{
			$to = $this->routes['*'][$to]['route'];
		}
		elseif (array_key_exists($to, $this->routes['get']))
		{
			$to = $this->routes['get'][$to]['route'];
		}

		$this->create('*', $from, $to, ['redirect' => $status]);

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Determines if the route is a redirecting route.
	 *
	 * @param string $from
	 *
	 * @return boolean
	 */
	public function isRedirect(string $from): bool
	{
		foreach ($this->routes['*'] as $name => $route)
		{
			// Named route?
			if ($name === $from || key($route['route']) === $from)
			{
				return isset($route['redirect']) && is_numeric($route['redirect']);
			}
		}

		return false;
	}

	//--------------------------------------------------------------------

	/**
	 * Grabs the HTTP status code from a redirecting Route.
	 *
	 * @param string $from
	 *
	 * @return integer
	 */
	public function getRedirectCode(string $from): int
	{
		foreach ($this->routes['*'] as $name => $route)
		{
			// Named route?
			if ($name === $from || key($route['route']) === $from)
			{
				return $route['redirect'] ?? 0;
			}
		}

		return 0;
	}

	//--------------------------------------------------------------------
	//--------------------------------------------------------------------
	// Grouping Routes
	//--------------------------------------------------------------------

	/**
	 * Group a series of routes under a single URL segment. This is handy
	 * for grouping items into an admin area, like:
	 *
	 * Example:
	 *     // Creates route: admin/users
	 *     $route->group('admin', function() {
	 *            $route->resource('users');
	 *     });
	 *
	 * @param string         $name      The name to group/prefix the routes with.
	 * @param array|callable ...$params
	 *
	 * @return void
	 */
	public function group(string $name, ...$params)
	{
		$oldGroup   = $this->group;
		$oldOptions = $this->currentOptions;

		// To register a route, we'll set a flag so that our router
		// so it will see the group name.
		// If the group name is empty, we go on using the previously built group name.
		$this->group = $name ? ltrim($oldGroup . '/' . $name, '/') : $oldGroup;

		$callback = array_pop($params);

		if ($params && is_array($params[0]))
		{
			$this->currentOptions = array_shift($params);
		}

		if (is_callable($callback))
		{
			$callback($this);
		}

		$this->group          = $oldGroup;
		$this->currentOptions = $oldOptions;
	}

	//--------------------------------------------------------------------
	//--------------------------------------------------------------------
	// HTTP Verb-based routing
	//--------------------------------------------------------------------
	// Routing works here because, as the routes Config file is read in,
	// the various HTTP verb-based routes will only be added to the in-memory
	// routes if it is a call that should respond to that verb.
	//
	// The options array is typically used to pass in an 'as' or var, but may
	// be expanded in the future. See the docblock for 'add' method above for
	// current list of globally available options.
	//

	/**
	 * Creates a collections of HTTP-verb based routes for a controller.
	 *
	 * Possible Options:
	 *      'controller'    - Customize the name of the controller used in the 'to' route
	 *      'placeholder'   - The regex used by the Router. Defaults to '(:any)'
	 *      'websafe'   -	- '1' if only GET and POST HTTP verbs are supported
	 *
	 * Example:
	 *
	 *      $route->resource('photos');
	 *
	 *      // Generates the following routes:
	 *      HTTP Verb | Path        | Action        | Used for...
	 *      ----------+-------------+---------------+-----------------
	 *      GET         /photos             index           an array of photo objects
	 *      GET         /photos/new         new             an empty photo object, with default properties
	 *      GET         /photos/{id}/edit   edit            a specific photo object, editable properties
	 *      GET         /photos/{id}        show            a specific photo object, all properties
	 *      POST        /photos             create          a new photo object, to add to the resource
	 *      DELETE      /photos/{id}        delete          deletes the specified photo object
	 *      PUT/PATCH   /photos/{id}        update          replacement properties for existing photo
	 *
	 *  If 'websafe' option is present, the following paths are also available:
	 *
	 *      POST		/photos/{id}/delete delete
	 *      POST        /photos/{id}        update
	 *
	 * @param string     $name    The name of the resource/controller to route to.
	 * @param array|null $options An list of possible ways to customize the routing.
	 *
	 * @return RouteCollectionInterface
	 */
	public function resource(string $name, array $options = null): RouteCollectionInterface
	{
		// In order to allow customization of the route the
		// resources are sent to, we need to have a new name
		// to store the values in.
		$newName = implode('\\', array_map('ucfirst', explode('/', $name)));
		// If a new controller is specified, then we replace the
		// $name value with the name of the new controller.
		if (isset($options['controller']))
		{
			$newName = ucfirst(filter_var($options['controller'], FILTER_SANITIZE_STRING));
		}

		// In order to allow customization of allowed id values
		// we need someplace to store them.
		$id = $this->placeholders[$this->defaultPlaceholder] ?? '(:segment)';

		if (isset($options['placeholder']))
		{
			$id = $options['placeholder'];
		}

		// Make sure we capture back-references
		$id = '(' . trim($id, '()') . ')';

		$methods = isset($options['only']) ? (is_string($options['only']) ? explode(',', $options['only']) : $options['only']) : ['index', 'show', 'create', 'update', 'delete', 'new', 'edit'];

		if (isset($options['except']))
		{
			$options['except'] = is_array($options['except']) ? $options['except'] : explode(',', $options['except']);
			foreach ($methods as $i => $method)
			{
				if (in_array($method, $options['except'], true))
				{
					unset($methods[$i]);
				}
			}
		}

		if (in_array('index', $methods, true))
		{
			$this->get($name, $newName . '::index', $options);
		}
		if (in_array('new', $methods, true))
		{
			$this->get($name . '/new', $newName . '::new', $options);
		}
		if (in_array('edit', $methods, true))
		{
			$this->get($name . '/' . $id . '/edit', $newName . '::edit/$1', $options);
		}
		if (in_array('show', $methods, true))
		{
			$this->get($name . '/' . $id, $newName . '::show/$1', $options);
		}
		if (in_array('create', $methods, true))
		{
			$this->post($name, $newName . '::create', $options);
		}
		if (in_array('update', $methods, true))
		{
			$this->put($name . '/' . $id, $newName . '::update/$1', $options);
			$this->patch($name . '/' . $id, $newName . '::update/$1', $options);
		}
		if (in_array('delete', $methods, true))
		{
			$this->delete($name . '/' . $id, $newName . '::delete/$1', $options);
		}

		// Web Safe? delete needs checking before update because of method name
		if (isset($options['websafe']))
		{
			if (in_array('delete', $methods, true))
			{
				$this->post($name . '/' . $id . '/delete', $newName . '::delete/$1', $options);
			}
			if (in_array('update', $methods, true))
			{
				$this->post($name . '/' . $id, $newName . '::update/$1', $options);
			}
		}

		return $this;
	}

	/**
	 * Creates a collections of HTTP-verb based routes for a presenter controller.
	 *
	 * Possible Options:
	 *      'controller'    - Customize the name of the controller used in the 'to' route
	 *      'placeholder'   - The regex used by the Router. Defaults to '(:any)'
	 *
	 * Example:
	 *
	 *      $route->presenter('photos');
	 *
	 *      // Generates the following routes:
	 *      HTTP Verb | Path        | Action        | Used for...
	 *      ----------+-------------+---------------+-----------------
	 *      GET         /photos             index           showing all array of photo objects
	 *      GET         /photos/show/{id}   show            showing a specific photo object, all properties
	 *      GET         /photos/new         new             showing a form for an empty photo object, with default properties
	 *      POST        /photos/create      create          processing the form for a new photo
	 *      GET         /photos/edit/{id}   edit            show an editing form for a specific photo object, editable properties
	 *      POST        /photos/update/{id} update          process the editing form data
	 *      GET         /photos/remove/{id} remove          show a form to confirm deletion of a specific photo object
	 *      POST        /photos/delete/{id} delete          deleting the specified photo object
	 *
	 * @param string     $name    The name of the controller to route to.
	 * @param array|null $options An list of possible ways to customize the routing.
	 *
	 * @return RouteCollectionInterface
	 */
	public function presenter(string $name, array $options = null): RouteCollectionInterface
	{
		// In order to allow customization of the route the
		// resources are sent to, we need to have a new name
		// to store the values in.
		$newName = implode('\\', array_map('ucfirst', explode('/', $name)));
		// If a new controller is specified, then we replace the
		// $name value with the name of the new controller.
		if (isset($options['controller']))
		{
			$newName = ucfirst(filter_var($options['controller'], FILTER_SANITIZE_STRING));
		}

		// In order to allow customization of allowed id values
		// we need someplace to store them.
		$id = $this->placeholders[$this->defaultPlaceholder] ?? '(:segment)';

		if (isset($options['placeholder']))
		{
			$id = $options['placeholder'];
		}

		// Make sure we capture back-references
		$id = '(' . trim($id, '()') . ')';

		$methods = isset($options['only']) ? (is_string($options['only']) ? explode(',', $options['only']) : $options['only']) : ['index', 'show', 'new', 'create', 'edit', 'update', 'remove', 'delete'];

		if (isset($options['except']))
		{
			$options['except'] = is_array($options['except']) ? $options['except'] : explode(',', $options['except']);
			foreach ($methods as $i => $method)
			{
				if (in_array($method, $options['except'], true))
				{
					unset($methods[$i]);
				}
			}
		}

		if (in_array('index', $methods, true))
		{
			$this->get($name, $newName . '::index', $options);
		}
		if (in_array('show', $methods, true))
		{
			$this->get($name . '/show/' . $id, $newName . '::show/$1', $options);
		}
		if (in_array('new', $methods, true))
		{
			$this->get($name . '/new', $newName . '::new', $options);
		}
		if (in_array('create', $methods, true))
		{
			$this->post($name . '/create', $newName . '::create', $options);
		}
		if (in_array('edit', $methods, true))
		{
			$this->get($name . '/edit/' . $id, $newName . '::edit/$1', $options);
		}
		if (in_array('update', $methods, true))
		{
			$this->post($name . '/update/' . $id, $newName . '::update/$1', $options);
		}
		if (in_array('remove', $methods, true))
		{
			$this->get($name . '/remove/' . $id, $newName . '::remove/$1', $options);
		}
		if (in_array('delete', $methods, true))
		{
			$this->post($name . '/delete/' . $id, $newName . '::delete/$1', $options);
		}
		if (in_array('show', $methods, true))
		{
			$this->get($name . '/' . $id, $newName . '::show/$1', $options);
		}
		if (in_array('create', $methods, true))
		{
			$this->post($name, $newName . '::create', $options);
		}

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Specifies a single route to match for multiple HTTP Verbs.
	 *
	 * Example:
	 *  $route->match( ['get', 'post'], 'users/(:num)', 'users/$1);
	 *
	 * @param array        $verbs
	 * @param string       $from
	 * @param string|array $to
	 * @param array|null   $options
	 *
	 * @return RouteCollectionInterface
	 */
	public function match(array $verbs = [], string $from = '', $to = '', array $options = null): RouteCollectionInterface
	{
		if (empty($from) || empty($to))
		{
			throw new InvalidArgumentException('You must supply the parameters: from, to.');
		}

		foreach ($verbs as $verb)
		{
			$verb = strtolower($verb);

			$this->{$verb}($from, $to, $options);
		}

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Specifies a route that is only available to GET requests.
	 *
	 * @param string       $from
	 * @param string|array $to
	 * @param array|null   $options
	 *
	 * @return RouteCollectionInterface
	 */
	public function get(string $from, $to, array $options = null): RouteCollectionInterface
	{
		$this->create('get', $from, $to, $options);

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Specifies a route that is only available to POST requests.
	 *
	 * @param string       $from
	 * @param string|array $to
	 * @param array|null   $options
	 *
	 * @return RouteCollectionInterface
	 */
	public function post(string $from, $to, array $options = null): RouteCollectionInterface
	{
		$this->create('post', $from, $to, $options);

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Specifies a route that is only available to PUT requests.
	 *
	 * @param string       $from
	 * @param string|array $to
	 * @param array|null   $options
	 *
	 * @return RouteCollectionInterface
	 */
	public function put(string $from, $to, array $options = null): RouteCollectionInterface
	{
		$this->create('put', $from, $to, $options);

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Specifies a route that is only available to DELETE requests.
	 *
	 * @param string       $from
	 * @param string|array $to
	 * @param array|null   $options
	 *
	 * @return RouteCollectionInterface
	 */
	public function delete(string $from, $to, array $options = null): RouteCollectionInterface
	{
		$this->create('delete', $from, $to, $options);

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Specifies a route that is only available to HEAD requests.
	 *
	 * @param string       $from
	 * @param string|array $to
	 * @param array|null   $options
	 *
	 * @return RouteCollectionInterface
	 */
	public function head(string $from, $to, array $options = null): RouteCollectionInterface
	{
		$this->create('head', $from, $to, $options);

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Specifies a route that is only available to PATCH requests.
	 *
	 * @param string       $from
	 * @param string|array $to
	 * @param array|null   $options
	 *
	 * @return RouteCollectionInterface
	 */
	public function patch(string $from, $to, array $options = null): RouteCollectionInterface
	{
		$this->create('patch', $from, $to, $options);

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Specifies a route that is only available to OPTIONS requests.
	 *
	 * @param string       $from
	 * @param string|array $to
	 * @param array|null   $options
	 *
	 * @return RouteCollectionInterface
	 */
	public function options(string $from, $to, array $options = null): RouteCollectionInterface
	{
		$this->create('options', $from, $to, $options);

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Specifies a route that is only available to command-line requests.
	 *
	 * @param string       $from
	 * @param string|array $to
	 * @param array|null   $options
	 *
	 * @return RouteCollectionInterface
	 */
	public function cli(string $from, $to, array $options = null): RouteCollectionInterface
	{
		$this->create('cli', $from, $to, $options);

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Limits the routes to a specified ENVIRONMENT or they won't run.
	 *
	 * @param string  $env
	 * @param Closure $callback
	 *
	 * @return RouteCollectionInterface
	 */
	public function environment(string $env, Closure $callback): RouteCollectionInterface
	{
		if (ENVIRONMENT === $env)
		{
			$callback($this);
		}

		return $this;
	}

	//--------------------------------------------------------------------

	/**
	 * Attempts to look up a route based on its destination.
	 *
	 * If a route exists:
	 *
	 *      'path/(:any)/(:any)' => 'Controller::method/$1/$2'
	 *
	 * This method allows you to know the Controller and method
	 * and get the route that leads to it.
	 *
	 *      // Equals 'path/$param1/$param2'
	 *      reverseRoute('Controller::method', $param1, $param2);
	 *
	 * @param string $search
	 * @param mixed  ...$params
	 *
	 * @return string|false
	 */
	public function reverseRoute(string $search, ...$params)
	{
		// Named routes get higher priority.
		foreach ($this->routes as $collection)
		{
			if (array_key_exists($search, $collection))
			{
				$route = $this->fillRouteParams(key($collection[$search]['route']), $params);
				return $this->localizeRoute($route);
			}
		}

		// If it's not a named route, then loop over
		// all routes to find a match.
		foreach ($this->routes as $collection)
		{
			foreach ($collection as $route)
			{
				$from = key($route['route']);
				$to   = $route['route'][$from];

				// ignore closures
				if (! is_string($to))
				{
					continue;
				}

				// Lose any namespace slash at beginning of strings
				// to ensure more consistent match.
				$to     = ltrim($to, '\\');
				$search = ltrim($search, '\\');

				// If there's any chance of a match, then it will
				// be with $search at the beginning of the $to string.
				if (strpos($to, $search) !== 0)
				{
					continue;
				}

				// Ensure that the number of $params given here
				// matches the number of back-references in the route
				if (substr_count($to, '$') !== count($params))
				{
					continue;
				}

				$route = $this->fillRouteParams($from, $params);
				return $this->localizeRoute($route);
			}
		}

		// If we're still here, then we did not find a match.
		return false;
	}

	//--------------------------------------------------------------------

	/**
	 * Replaces the {locale} tag with the current application locale
	 *
	 * @param string $route
	 *
	 * @return string
	 */
	protected function localizeRoute(string $route) :string
	{
		return strtr($route, ['{locale}' => Services::request()->getLocale()]);
	}

	//--------------------------------------------------------------------

	/**
	 * Checks a route (using the "from") to see if it's filtered or not.
	 *
	 * @param string      $search
	 * @param string|null $verb
	 *
	 * @return boolean
	 */
	public function isFiltered(string $search, string $verb = null): bool
	{
		$options = $this->loadRoutesOptions($verb);

		return isset($options[$search]['filter']);
	}

	//--------------------------------------------------------------------

	/**
	 * Returns the filter that should be applied for a single route, along
	 * with any parameters it might have. Parameters are found by splitting
	 * the parameter name on a colon to separate the filter name from the parameter list,
	 * and the splitting the result on commas. So:
	 *
	 *    'role:admin,manager'
	 *
	 * has a filter of "role", with parameters of ['admin', 'manager'].
	 *
	 * @param string      $search
	 * @param string|null $verb
	 *
	 * @return string
	 */
	public function getFilterForRoute(string $search, string $verb = null): string
	{
		$options = $this->loadRoutesOptions($verb);

		return $options[$search]['filter'] ?? '';
	}

	//--------------------------------------------------------------------

	/**
	 * Given a
	 *
	 * @param string     $from
	 * @param array|null $params
	 *
	 * @return string
	 * @throws RouterException
	 */
	protected function fillRouteParams(string $from, array $params = null): string
	{
		// Find all of our back-references in the original route
		preg_match_all('/\(([^)]+)\)/', $from, $matches);

		if (empty($matches[0]))
		{
			return '/' . ltrim($from, '/');
		}

		// Build our resulting string, inserting the $params in
		// the appropriate places.
		foreach ($matches[0] as $index => $pattern)
		{
			if (! preg_match('#^' . $pattern . '$#u', $params[$index]))
			{
				throw RouterException::forInvalidParameterType();
			}

			// Ensure that the param we're inserting matches
			// the expected param type.
			$pos  = strpos($from, $pattern);
			$from = substr_replace($from, $params[$index], $pos, strlen($pattern));
		}

		return '/' . ltrim($from, '/');
	}

	//--------------------------------------------------------------------

	/**
	 * Does the heavy lifting of creating an actual route. You must specify
	 * the request method(s) that this route will work for. They can be separated
	 * by a pipe character "|" if there is more than one.
	 *
	 * @param string       $verb
	 * @param string       $from
	 * @param string|array $to
	 * @param array|null   $options
	 */
	protected function create(string $verb, string $from, $to, array $options = null)
	{
		$overwrite = false;
		$prefix    = is_null($this->group) ? '' : $this->group . '/';

		$from = filter_var($prefix . $from, FILTER_SANITIZE_STRING);

		// While we want to add a route within a group of '/',
		// it doesn't work with matching, so remove them...
		if ($from !== '/')
		{
			$from = trim($from, '/');
		}

		$options = array_merge($this->currentOptions ?? [], $options ?? []);

		// Hostname limiting?
		if (! empty($options['hostname']))
		{
			// @todo determine if there's a way to whitelist hosts?
			if (isset($_SERVER['HTTP_HOST']) && strtolower($_SERVER['HTTP_HOST']) !== strtolower($options['hostname']))
			{
				return;
			}

			$overwrite = true;
		}

		// Limiting to subdomains?
		elseif (! empty($options['subdomain']))
		{
			// If we don't match the current subdomain, then
			// we don't need to add the route.
			if (! $this->checkSubdomains($options['subdomain']))
			{
				return;
			}

			$overwrite = true;
		}

		// Are we offsetting the binds?
		// If so, take care of them here in one
		// fell swoop.
		if (isset($options['offset']) && is_string($to))
		{
			// Get a constant string to work with.
			$to = preg_replace('/(\$\d+)/', '$X', $to);

			for ($i = (int) $options['offset'] + 1; $i < (int) $options['offset'] + 7; $i ++)
			{
				$to = preg_replace_callback(
						'/\$X/', function ($m) use ($i) {
							return '$' . $i;
						}, $to, 1
				);
			}
		}

		// Replace our regex pattern placeholders with the actual thing
		// so that the Router doesn't need to know about any of this.
		foreach ($this->placeholders as $tag => $pattern)
		{
			$from = str_ireplace(':' . $tag, $pattern, $from);
		}

		//If is redirect, No processing
		if (! isset($options['redirect']))
		{
			if (is_string($to))
			{
				// If no namespace found, add the default namespace
				if (strpos($to, '\\') === false || strpos($to, '\\') > 0)
				{
					$namespace = $options['namespace'] ?? $this->defaultNamespace;
					$to        = trim($namespace, '\\') . '\\' . $to;
				}

				// Always ensure that we escape our namespace so we're not pointing to
				// \CodeIgniter\Routes\Controller::method.
				$to = '\\' . ltrim($to, '\\');
			}
		}

		$name = $options['as'] ?? $from;

		// Don't overwrite any existing 'froms' so that auto-discovered routes
		// do not overwrite any app/Config/Routes settings. The app
		// routes should always be the "source of truth".
		// this works only because discovered routes are added just prior
		// to attempting to route the request.
		if (isset($this->routes[$verb][$name]) && ! $overwrite)
		{
			return;
		}

		$this->routes[$verb][$name] = [
			'route' => [$from => $to],
		];

		$this->routesOptions[$verb][$from] = $options;

		// Is this a redirect?
		if (isset($options['redirect']) && is_numeric($options['redirect']))
		{
			$this->routes['*'][$name]['redirect'] = $options['redirect'];
		}
	}

	//--------------------------------------------------------------------

	/**
	 * Compares the subdomain(s) passed in against the current subdomain
	 * on this page request.
	 *
	 * @param mixed $subdomains
	 *
	 * @return boolean
	 */
	private function checkSubdomains($subdomains): bool
	{
		// CLI calls can't be on subdomain.
		if (! isset($_SERVER['HTTP_HOST']))
		{
			return false;
		}

		if (is_null($this->currentSubdomain))
		{
			$this->currentSubdomain = $this->determineCurrentSubdomain();
		}

		if (! is_array($subdomains))
		{
			$subdomains = [$subdomains];
		}

		// Routes can be limited to any sub-domain. In that case, though,
		// it does require a sub-domain to be present.
		if (! empty($this->currentSubdomain) && in_array('*', $subdomains, true))
		{
			return true;
		}

		return in_array($this->currentSubdomain, $subdomains, true);
	}

	//--------------------------------------------------------------------

	/**
	 * Examines the HTTP_HOST to get a best match for the subdomain. It
	 * won't be perfect, but should work for our needs.
	 *
	 * It's especially not perfect since it's possible to register a domain
	 * with a period (.) as part of the domain name.
	 *
	 * @return mixed
	 */
	private function determineCurrentSubdomain()
	{
		// We have to ensure that a scheme exists
		// on the URL else parse_url will mis-interpret
		// 'host' as the 'path'.
		$url = $_SERVER['HTTP_HOST'];
		if (strpos($url, 'http') !== 0)
		{
			$url = 'http://' . $url;
		}

		$parsedUrl = parse_url($url);

		$host = explode('.', $parsedUrl['host']);

		if ($host[0] === 'www')
		{
			unset($host[0]);
		}

		// Get rid of any domains, which will be the last
		unset($host[count($host)]);

		// Account for .co.uk, .co.nz, etc. domains
		if (end($host) === 'co')
		{
			$host = array_slice($host, 0, -1);
		}

		// If we only have 1 part left, then we don't have a sub-domain.
		if (count($host) === 1)
		{
			// Set it to false so we don't make it back here again.
			return false;
		}

		return array_shift($host);
	}

	//--------------------------------------------------------------------

	/**
	 * Reset the routes, so that a FeatureTestCase can provide the
	 * explicit ones needed for it.
	 */
	public function resetRoutes()
	{
		$this->routes = ['*' => []];
		foreach ($this->defaultHTTPMethods as $verb)
		{
			$this->routes[$verb] = [];
		}
	}

	//--------------------------------------------------------------------

	/**
	 * Load routes options based on verb
	 *
	 * @param string|null $verb
	 *
	 * @return array
	 */
	protected function loadRoutesOptions(string $verb = null): array
	{
		$verb = $verb ?: $this->getHTTPVerb();

		$options = $this->routesOptions[$verb] ?? [];

		if (isset($this->routesOptions['*']))
		{
			foreach ($this->routesOptions['*'] as $key => $val)
			{
				if (isset($options[$key]))
				{
					$extraOptions  = array_diff_key($val, $options[$key]);
					$options[$key] = array_merge($options[$key], $extraOptions);
				}
				else
				{
					$options[$key] = $val;
				}
			}
		}

		return $options;
	}
}
