<?php

/**

 * Case-insensitive dictionary, suitable for HTTP headers

 *

 * @package Requests

 */

/**

 * Case-insensitive dictionary, suitable for HTTP headers

 *

 * @package Requests

 */

class Requests_Response_Headers extends Requests_Utility_CaseInsensitiveDictionary {

	/**

	 * Get the given header

	 *

	 * Unlike {@see self::getValues()}, this returns a string. If there are

	 * multiple values, it concatenates them with a comma as per RFC2616.

	 *

	 * Avoid using this where commas may be used unquoted in values, such as

	 * Set-Cookie headers.

	 *

	 * @param string $key

	 * @return string|null Header value

	 */

	public function offsetGet($key) {

		$key = strtolower($key);

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

			return null;

		}

		return $this->flatten($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);

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

			$this->data[$key] = array();

		}

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

	}

	/**

	 * Get all values for a given header

	 *

	 * @param string $key

	 * @return array|null Header values

	 */

	public function getValues($key) {

		$key = strtolower($key);

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

			return null;

		}

		return $this->data[$key];

	}

	/**

	 * Flattens a value into a string

	 *

	 * Converts an array into a string by imploding values with a comma, as per

	 * RFC2616's rules for folding headers.

	 *

	 * @param string|array $value Value to flatten

	 * @return string Flattened value

	 */

	public function flatten($value) {

		if (is_array($value)) {

			$value = implode(',', $value);

		}

		return $value;

	}

	/**

	 * Get an iterator for the data

	 *

	 * Converts the internal

	 * @return ArrayIterator

	 */

	public function getIterator() {

		return new Requests_Utility_FilteredIterator($this->data, array($this, 'flatten'));

	}

}