<?php
/**
 * IniReader
 *
 * PHP 5
 *
 * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
 * Copyright 2005-2011, Cake Software Foundation, Inc. (http://cakefoundation.org)
 *
 * Licensed under The MIT License
 * Redistributions of files must retain the above copyright notice.
 *
 * @copyright     Copyright 2005-2011, Cake Software Foundation, Inc. (http://cakefoundation.org)
 * @link          http://cakephp.org CakePHP(tm) Project
 * @package       Cake.Configure
 * @since         CakePHP(tm) v 2.0
 * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
 */

/**
 * Ini file configuration parser.  Since IniReader uses parse_ini_file underneath,
 * you should be aware that this class shares the same behavior, especially with
 * regards to boolean and null values.
 *
 * In addition to the native parse_ini_file features, IniReader also allows you
 * to create nested array structures through usage of `.` delimited names.  This allows
 * you to create nested arrays structures in an ini config file. For example:
 *
 * `db.password = secret` would turn into `array('db' => array('password' => 'secret'))`
 *
 * You can nest properties as deeply as needed using `.`'s. In addition to using `.` you
 * can use standard ini section notation to create nested structures:
 *
 * {{{
 * [section]
 * key = value
 * }}}
 *
 * Once loaded into Configure, the above would be accessed using:
 *
 * `Configure::read('section.key');
 *
 * You can combine `.` separated values with sections to create more deeply
 * nested structures.
 *
 * IniReader also manipulates how the special ini values of 
 * 'yes', 'no', 'on', 'off', 'null' are handled. These values will be 
 * converted to their boolean equivalents.
 *
 * @package       Cake.Configure
 * @see http://php.net/parse_ini_file
 */
class IniReader implements ConfigReaderInterface {

/**
 * The path to read ini files from.
 *
 * @var array
 */
	protected $_path;

/**
 * The section to read, if null all sections will be read.
 *
 * @var string
 */
	protected $_section;

/**
 * Build and construct a new ini file parser. The parser can be used to read
 * ini files that are on the filesystem.
 *
 * @param string $path Path to load ini config files from.
 * @param string $section Only get one section, leave null to parse and fetch
 *     all sections in the ini file.
 */
	public function __construct($path, $section = null) {
		$this->_path = $path;
		$this->_section = $section;
	}

/**
 * Read an ini file and return the results as an array.
 *
 * @param string $file Name of the file to read. The chosen file
 *    must be on the reader's path.
 * @return array
 */
	public function read($file) {
		$filename = $this->_path . $file;
		if (!file_exists($filename)) {
			$filename .= '.ini';
			if (!file_exists($filename)) {
				throw new ConfigureException(__d('cake_dev', 'Could not load configuration files: %s or %s', substr($filename, 0, -4), $filename));
			}
		}
		$contents = parse_ini_file($filename, true);
		if (!empty($this->_section) && isset($contents[$this->_section])) {
			$values = $this->_parseNestedValues($contents[$this->_section]);
		} else {
			$values = array();
			foreach ($contents as $section => $attribs) {
				if (is_array($attribs)) {
					$values[$section] = $this->_parseNestedValues($attribs);
				} else {
					$parse = $this->_parseNestedValues(array($attribs));
					$values[$section] = array_shift($parse);
				}
			}
		}
		return $values;
	}

/**
 * parses nested values out of keys.
 *
 * @param array $values Values to be exploded.
 * @return array Array of values exploded
 */
	protected function _parseNestedValues($values) {
		foreach ($values as $key => $value) {
			if ($value === '1') {
				$value = true;
			}
			if ($value === '') {
				$value = false;
			}
			if (strpos($key, '.') !== false) {
				$values = Set::insert($values, $key, $value);
			} else {
				$values[$key] = $value;
			}
		}
		return $values;
	}
}