Chris@0: <?php
Chris@0: 
Chris@0: /*
Chris@0:  * This file is part of the Symfony package.
Chris@0:  *
Chris@0:  * (c) Fabien Potencier <fabien@symfony.com>
Chris@0:  *
Chris@0:  * For the full copyright and license information, please view the LICENSE
Chris@0:  * file that was distributed with this source code.
Chris@0:  */
Chris@0: 
Chris@0: namespace Symfony\Component\BrowserKit;
Chris@0: 
Chris@0: /**
Chris@0:  * History.
Chris@0:  *
Chris@0:  * @author Fabien Potencier <fabien@symfony.com>
Chris@0:  */
Chris@0: class History
Chris@0: {
Chris@17:     protected $stack = [];
Chris@0:     protected $position = -1;
Chris@0: 
Chris@0:     /**
Chris@0:      * Clears the history.
Chris@0:      */
Chris@0:     public function clear()
Chris@0:     {
Chris@17:         $this->stack = [];
Chris@0:         $this->position = -1;
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Adds a Request to the history.
Chris@0:      */
Chris@0:     public function add(Request $request)
Chris@0:     {
Chris@17:         $this->stack = \array_slice($this->stack, 0, $this->position + 1);
Chris@0:         $this->stack[] = clone $request;
Chris@17:         $this->position = \count($this->stack) - 1;
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Returns true if the history is empty.
Chris@0:      *
Chris@0:      * @return bool true if the history is empty, false otherwise
Chris@0:      */
Chris@0:     public function isEmpty()
Chris@0:     {
Chris@17:         return 0 == \count($this->stack);
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Goes back in the history.
Chris@0:      *
Chris@0:      * @return Request A Request instance
Chris@0:      *
Chris@0:      * @throws \LogicException if the stack is already on the first page
Chris@0:      */
Chris@0:     public function back()
Chris@0:     {
Chris@0:         if ($this->position < 1) {
Chris@0:             throw new \LogicException('You are already on the first page.');
Chris@0:         }
Chris@0: 
Chris@0:         return clone $this->stack[--$this->position];
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Goes forward in the history.
Chris@0:      *
Chris@0:      * @return Request A Request instance
Chris@0:      *
Chris@0:      * @throws \LogicException if the stack is already on the last page
Chris@0:      */
Chris@0:     public function forward()
Chris@0:     {
Chris@17:         if ($this->position > \count($this->stack) - 2) {
Chris@0:             throw new \LogicException('You are already on the last page.');
Chris@0:         }
Chris@0: 
Chris@0:         return clone $this->stack[++$this->position];
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Returns the current element in the history.
Chris@0:      *
Chris@0:      * @return Request A Request instance
Chris@0:      *
Chris@0:      * @throws \LogicException if the stack is empty
Chris@0:      */
Chris@0:     public function current()
Chris@0:     {
Chris@0:         if (-1 == $this->position) {
Chris@0:             throw new \LogicException('The page history is empty.');
Chris@0:         }
Chris@0: 
Chris@0:         return clone $this->stack[$this->position];
Chris@0:     }
Chris@0: }