<?php defined('SYSPATH') or die('No direct access allowed.');

/**
 * This class takes care of searching within LDAP
 *
 * @package    Kohana/LDAP
 * @category   Helpers
 * @author     Deon George
 * @copyright  (c) 2013 phpLDAPadmin Development Team
 * @license    http://dev.phpldapadmin.org/license.html
 */
abstract class Kohana_Database_LDAP_Search {
	private $_db;				// Our LDAP Server to query

	private $_attrs = array('*','+');	// LDAP Attributes to Return
	private $_base = array();		// LDAP Search Base
	private $_deref = LDAP_DEREF_NEVER;	// LDAP Search Default DEREF
	private $_filter = '(objectclass=*)';	// LDAP Search Filter
	private $_size_limit = '500';		// LDAP Search Size Limit
	private $_scope = 'base';		// LDAP Search Scope
	private $_time_limit = '60';		// LDAP Search Time Limit
	private $_db_pending = array();		// LDAP Query Filter to compile

	// Execute the query during a cache hit
	protected $_force_execute = FALSE;

	// Cache lifetime
	protected $_lifetime = NULL;

	/**
	 * Callable database methods
	 * @var array
	 */
	protected static $_db_methods = array(
		'where', 'and_where', 'or_where', 'where_open', 'and_where_open', 'or_where_open', 'where_close',
		'and_where_close', 'or_where_close',
	);

	/**
	 * Members that have access methods
	 * @var array
	 */
	protected static $_properties = array(
	);

	public function __construct(Database_LDAP $db,$base=array()) {
		$this->_db = $db;

		$this->_base = is_null($base) ? $this->base() : $base;
	}

	/**
	 * Handles pass-through to database methods. Calls to query methods
	 * (query, get, insert, update) are not allowed. Query builder methods
	 * are chainable.
	 *
	 * @param   string  $method Method name
	 * @param   array   $args   Method arguments
	 * @return  mixed
	 */
	public function __call($method,array $args) {
		if (in_array($method,Database_LDAP_Search::$_properties)) {
			/*
			// @todo To Implement
			if ($method === 'validation')
			{
				if ( ! isset($this->_validation))
				{
					// Initialize the validation object
					$this->_validation();
				}
			}
			*/

			// Return the property
			return $this->{'_'.$method};
		}
		elseif (in_array($method,Database_LDAP_Search::$_db_methods))
		{
			// Add pending database call which is executed after query type is determined
			$this->_db_pending[] = array('name' => $method,'args' => $args);

			return $this;
		}
		else
		{
			throw new Kohana_Exception('Invalid method :method called in :class',
				array(':method' => $method,':class' => get_class($this)));
		}
	}

	private function _build() {
		$search = new Database_LDAP_Search_Builder_Query();

		// Process pending database method calls
		foreach ($this->_db_pending as $method) {
			$name = $method['name'];
			$args = $method['args'];

			$this->_db_applied[$name] = $name;

			call_user_func_array(array($search,$name),$args);
		}

		return $search;
	}

	/**
	 * Figure out the bases
	 */
	public function base() {
		// If the base is set in the configuration file, then just return that.
		if (! is_null($x=Kohana::$config->load('database.default.connection.database')))
			return $x;

		$x = LDAP::factory('auth');

		$u = $x->search(array(''))
			->scope('base')
			->run();

		// Remove the '' base
		$u = array_pop($u);

		// Quick validation
		if ($u->count() > 1)
			throw HTTP_Exception::factory(501,'We got more than 1 null DN?');

		return isset($u['']['namingcontexts']) ? $u['']['namingcontexts'] : array();
	}

	/**
	 * Enables the query to be cached for a specified amount of time.
	 *
	 * @param   integer  $lifetime  number of seconds to cache, 0 deletes it from the cache
	 * @param   boolean  whether or not to execute the query during a cache hit
	 * @return  $this
	 * @uses    Kohana::$cache_life
	 */
	public function cached($lifetime=NULL,$force=FALSE) {
		if ($lifetime === NULL) {
			// Use the global setting
			$lifetime = Kohana::$cache_life;
		}

		$this->_force_execute = $force;
		$this->_lifetime = $lifetime;

		return $this;
	}

	public function deref($val) {
		$this->_deref = $val;

		return $this;
	}

	/**
	 * Search the LDAP database
	 */
	public function run($as_object=FALSE,$object_params=NULL) {
		$query = array();

		// Query Defaults
		$attrs_only = 0;

		// Compile our query
		if ($this->_db_pending)
			$this->_filter = $this->_build();

		$result = array();
		foreach ($this->_base as $base) {
			$result[$base] = NULL;

			if ($this->_lifetime !== NULL AND $this->_db->caching()) {
				// Set the cache key based on the database instance name and SQL
				$cache_key = 'Database::query("'.$this->_db.'","'.$base.'","'.$this->_scope.'","'.$this->_filter.'")';

				// Read the cache first to delete a possible hit with lifetime <= 0
				if (($search = Kohana::cache($cache_key, NULL, $this->_lifetime)) !== NULL AND ! $this->_force_execute) {
					// Return a cached result
					$result[$base] = new Database_LDAP_Result_Cached($search, array('b'=>$base,'s'=>$this->_scope,'f'=>$this->_filter), $as_object, $object_params);
				}
			}

			// Search is not cached, OR caching is disabled, so we'll query
			if (! $result[$base]) {
				switch ($this->_scope) {
					case 'base':
						$search = ldap_read($this->_db->connection(),$base,$this->_filter,$this->_attrs,$attrs_only,$this->_size_limit,$this->_time_limit,$this->_deref);
						break;

					case 'one':
						$search = ldap_list($this->_db->connection(),$base,$this->_filter,$this->_attrs,$attrs_only,$this->_size_limit,$this->_time_limit,$this->_deref);
						break;

					case 'sub':
					default:
						$search = ldap_search($this->_db->connection(),$base,$this->_filter,$this->_attrs,$attrs_only,$this->_size_limit,$this->_time_limit,$this->_deref);
						break;
				}

				$result[$base] = new Database_LDAP_Result(array('l'=>$this->_db->connection(),'r'=>$search),array('b'=>$base,'s'=>$this->_scope,'f'=>$this->_filter),$as_object,$object_params);

				// Cache the result array
				if (isset($cache_key) AND $this->_lifetime > 0)
					Kohana::cache($cache_key,$result[$base]->as_array(),$this->_lifetime);
			}
		}

		return $result;
	}

	public function size_limit($val) {
		$this->_size_limit = $val;

		return $this;
	}

	public function scope($val) {
		switch ($val) {
			case 'base':
			case 'sub':
			case 'one': $this->_scope = $val;
				break;

			default:
				throw new Kohana_Exception('Unknown search scope :scope',array(':scope',$val));
		}

		return $this;
	}

	public function time_limit($val) {
		$this->_time_limit = $val;

		return $this;
	}
}
?>