<?php

/**

 * Case-insensitive dictionary, suitable for HTTP headers

 *

 * @package Requests

 * @subpackage Utilities

 */

/**

 * Case-insensitive dictionary, suitable for HTTP headers

 *

 * @package Requests

 * @subpackage Utilities

 */

class Requests_Utility_CaseInsensitiveDictionary implements ArrayAccess, IteratorAggregate {

	/**

	 * Actual item data

	 *

	 * @var array

	 */

	protected $data = array();

	/**

	 * Creates a case insensitive dictionary.

	 *

	 * @param array $data Dictionary/map to convert to case-insensitive

	 */

	public function __construct(array $data = array()) {

		foreach ($data as $key => $value) {

			$this->offsetSet($key, $value);

		}

	}

	/**

	 * Check if the given item exists

	 *

	 * @param string $key Item key

	 * @return boolean Does the item exist?

	 */

	public function offsetExists($key) {

		$key = strtolower($key);

		return isset($this->data[$key]);

	}

	/**

	 * Get the value for the item

	 *

	 * @param string $key Item key

	 * @return string|null Item value (null if offsetExists is false)

	 */

	public function offsetGet($key) {

		$key = strtolower($key);

		if (!isset($this->data[$key])) {

			return null;

		}

		return $this->data[$key];

	}

	/**

	 * Set the given item

	 *

	 * @throws Requests_Exception On attempting to use dictionary as list (`invalidset`)

	 *

	 * @param string $key Item name

	 * @param string $value Item value

	 */

	public function offsetSet($key, $value) {

		if ($key === null) {

			throw new Requests_Exception('Object is a dictionary, not a list', 'invalidset');

		}

		$key              = strtolower($key);

		$this->data[$key] = $value;

	}

	/**

	 * Unset the given header

	 *

	 * @param string $key

	 */

	public function offsetUnset($key) {

		unset($this->data[strtolower($key)]);

	}

	/**

	 * Get an iterator for the data

	 *

	 * @return ArrayIterator

	 */

	public function getIterator() {

		return new ArrayIterator($this->data);

	}

	/**

	 * Get the headers as an array

	 *

	 * @return array Header data

	 */

	public function getAll() {

		return $this->data;

	}

}