/source/core/thirdparty/autoCrud/relationship.inc.php

<?php

/**

* AutoCRUD_Relationship Class File

*

* This file holds the AutoCRUD_Relationship class, used for joins

*

* @license http://www.opensource.org/licenses/mit-license.php MIT License

* @package autocrud

*/



/**

* AutoCRUD_Relationship Class

*

* This class is used to handle the joins and relationships between tables

* 

* @package autocrud

*/

Class AutoCRUD_Relationship {



	// Private vars:

	/**#@+

	* @access private

	*/

	var $_owner_obj;

	var $_other_obj;



	var $_owner_field;

	var $_other_field;



	var $_type;

	var $_reverse_type;

	/**#@-*/



	/**

	* Used to pass in the owner CRUD object and the CRUD object of the other table

	*

	* @access public

	* @param AutoCRUD_CRUD $owner the owner CRUD object

	* @param AutoCRUD_CRUD $other the CRUD object of the other table

	*/

	function AutoCRUD_Relationship(&$owner, &$other) {

		if (strtolower(get_class($owner)) != 'autocrud_crud') {

			return false;

		}



		if (strtolower(get_class($other)) != 'autocrud_crud') {

			return $this->halt ('invalid-object', 'Invalid object passed to relationship');

		}



		$this->_owner_obj =& $owner;

		$this->_other_obj =& $other;



		return true;

	}



	/**

	* Used to get related records of a result set

	*

	* @access public

	* @param array $results the result set (an array of records)

	* @return array the result set with related records

	*/

	function doJoin($results) {

		if ($this->_type == 'one-to-one') {

			$results = $this->_joinOne2One($results);

		} elseif ($this->_type == 'child-parent') {

			$results = $this->_joinChildParent($results);

		} else { 

			$results = $this->_joinOne2Many($results);

		}

		

		return $results;

	}



	/**

	* Used to get related records of a result set in a Many-to-Many relationship

	*

	* @access public

	* @param array $results the result set (an array of records)

	* @param string $table the name of the other table

	* @return array the result set with related records

	*/

	function joinMany2Many($results, $table) {

		// Get relationship

		$other_rel = $this->_other_obj->getRelationship($table);

		

		if (autocrud_is_error($other_rel)) { return $this->halt('no-relationship'); }



		// Get other object and other fields

		$other_obj =& $other_rel->getOther();

		$owner_field = $other_rel->getOwnerField();

		$other_field = $other_rel->getOtherField();



		$ids_list = array();

		$newresults = array();

		$keys = array();



		// Get ID's from results

		foreach ($results as $key => $row) {

			// Get ID

			$id = $row[$this->_owner_field];

			$ids_list[] = $id;



			// Copy to a new array, and add it under its own ID

			$newresults[$id] = $row;



			// Save key (in case a specific key was being used)

			$keys[] = $key;

		}

		$results = $newresults;

		$ids_list = array_unique($ids_list);

		$ids_list = implode("', '", $ids_list);



		// Get records from in between table

		$this->_other_obj->where = "`" . $this->_other_field . "` IN ('" . $ids_list . "')";

		$between = $this->_other_obj->select();



		// Collect ID's from in between table

		$ids_list = array();

		foreach ($between as $row) {

			// Get ID

			$id = $row[$table];

			$ids_list[] = $id;



		}

		$ids_list = array_unique($ids_list);

		$ids_list = implode("', '", $ids_list);



		// Get records from other table

		$crud =& $this->_other_obj->getParent();

		$other_obj->where = "`" . $other_field . "` IN ('" . $ids_list . "')";

		$other = $other_obj->select($other_field);



		// Match up results with other records

		$name = $other_obj->getName();

		foreach ($between as $row) {

			$id_owner = $row[$this->_other_field];

			$id_other = $row[$owner_field];



			// Owner exists?

			if (!isset($results[$id_owner])) { continue; }



			// Other exists?

			if (!isset($other[$id_other])) { continue; }



			$owner_row =& $results[$id_owner];

			$other_row =& $other[$id_other];



			// Make sure owner table array property exists

			if (!isset($owner_row[$name])) { $owner_row[$name] = array(); }



			// Add other row to owner

			$owner_row[$name][] = $other_row;

		}

		

		// Return keys

		$newresults = array();

		$i = 0;

		foreach ($results as $row) {

			$key = $keys[$i];

			$newresults[$key] = $row;

			$i++;

		}

		$results = $newresults;



		return $results;

	}



	/**

	* Used to add a relationship on the other CRUD object type (in reverse)

	*

	* @access public

	*/

	function createReverseRelationship() {

		// Create relationship on other object

		$this->_other_obj->addRelationship(&$this->_owner_obj, $this->_other_field, $this->_owner_field, $this->_reverse_type);

	}



	/**

	* Returns the owner CRUD object

	* @access public

	* @return AutoCRUD_CRUD

	*/

	function &getOwner() { return $this->_owner_obj; }



	/**

	* Returns the other CRUD object

	* @access public

	* @return AutoCRUD_CRUD

	*/

	function &getOther() { return $this->_other_obj; }



	/**

	* Used to set the fields used in the relationship

	*

	* @access public

	* @param string $owner name of the owner field

	* @param string $other name of the other field

	*/

	function setFields($owner, $other) {

		$this->_owner_field = $owner;

		$this->_other_field = $other;



		return true;

	}



	/**

	* Returns the field of the owner table

	* @access public

	* @return string

	*/

	function getOwnerField() { return $this->_owner_field; }



	/**

	* Returns the field of the other table

	* @access public

	* @return string

	*/

	function getOtherField() { return $this->_other_field; }



	/**

	* Used to set the type of relationship

	*

	* @access public

	* @param string $type the type of relationship, valid types are one-to-one, 

	* many-to-one, one-to-many, many-to-many and child-parent

	* @return mixed true on success, error object on failure

	*/

	function setType($type) {

		// Check type of relationship:

		// - one-to-one: both tables only have one record, e.g. a article table with an author in the author table (and each article has only one author).

		// - many-to-one: the first table ($this->table) has many records which link to one record in the second table, e.g. comments table and a article table.

		// - one-to-many: the first table ($this->table) has one records which links to many records in the second table, basically the many-to-one relationship turned around

		// - many-to-many: the first table ($this->table) has many records which links to many records in the second table. This type of relationship must use a third table for the relation ship, for example a users table and groups table needs a membership table which links both tables.

		// - child-parent: this relation only concerns one category and is used when rows can have sub-rows. Field 1 refers to the 'parent' field and field 2 to the primary key field (the parent identifier anyway)

		$types = array('one-to-one', 'many-to-one', 'one-to-many', 'many-to-many', 'child-parent');



		if (in_array($type, $types) == false) {

			return $this->halt ('invalid-type', 'Invalid relationship type passed');

		}



		// Detect reverse type

		if ($type == 'many-to-one') { 

			$reverse_type = 'one-to-many';

		} elseif ($type == 'one-to-many') {

			$reverse_type = 'many-to-one';

		} else {

			$reverse_type = $type;

		}



		// Many-to-one is really a one-to-one relationship (for this table, for the other table it's one-to-many)

		if ($type == 'many-to-one') { $type = 'one-to-one'; }



		// Set type and reverse type

		$this->_type = $type;

		$this->_reverse_type = $reverse_type;

	}



	/**

	* Returns the relationship type

	* @access public

	* @return string

	*/

	function getType() {

		return $this->_type;

	}

	

	/**

	* Returns the reverse relationship type (e.g. many-to-one when the relationship type is one-to-many)

	* @access public

	* @return string

	*/

	function getReverseType() {

		return $this->_reverse_type;

	}



	

	//================================================================================

	// Private functions start here

	//================================================================================



	/**#@+

	* @access private

	*/



	function halt($code, $msg='') {

		return $this->_owner_obj->halt($code, $msg);

	}



	function _joinChildParent($results) {

		// Get ID's from results

		$ids_list = array();

		$newresults = array();

		$keys = array();



		foreach ($results as $key => $row) {

			$id = $row[$this->_other_field];

			$ids_list[] = $id;

			$ids_list[] = $row[$this->_other_field];

			$newresults[$id] = $row;

			$keys[] = $key;

		}

		$results = $newresults;

		$ids_list = array_unique($ids_list);

		$ids_list = implode("', '", $ids_list);



		// Get rows from other table

		$this->_other_obj->where = $this->_owner_field . " IN ('" . $ids_list . "') OR " . $this->_other_field . " IN ('" . $ids_list . "')";

		$other = $this->_other_obj->select($this->_other_field);



		// Match every row from other with correct parent

		foreach ($other as $row) {

			$parent = $row[$this->_owner_field];

			if (isset($results[$parent]) == false) { continue; }

			

			if (isset($results[$parent]['children']) == false) { 

				$results[$parent]['children'] = array();

			}



			$results[$parent]['children'][] = $row;

		}



		// Find parents and return keys

		$newresults = array();

		$i = 0;

		foreach ($results as $row) {

			$parent = $row[$this->_owner_field];



			// Try and find parent

			if (isset($other[$parent]) == true) {

				$row[$this->_owner_field] = $other[$parent];

			}



			// Return original key

			$key = $keys[$i];

			$newresults[$key] = $row;

			$i++;

		}

		$results = $newresults;



		return $results;

	}



	function _joinOne2Many ($results) {

		$ids_list = array();

		$newresults = array();

		$keys = array();



		// Get ID's from results

		foreach ($results as $key => $row) {

			// Get ID

			$id = $row[$this->_owner_field];

			$ids_list[] = $id;



			// Copy to a new array, and add it under its own ID

			$newresults[$id] = $row;



			// Save key (in case a specific key was being used)

			$keys[] = $key;

		}

		$results = $newresults;

		$ids_list = array_unique($ids_list);

		$ids_list = implode("', '", $ids_list);



		// Get rows from other table

		$this->_other_obj->where = "`" . $this->_other_field . "` IN ('" . $ids_list . "')";

		$other = $this->_other_obj->select();



		// Match other results with results

		$name = $this->_other_obj->getName();

		foreach ($other as $row) {

			$id = $row[$this->_other_field];



			// Make sure that array for other rows exist on owner

			if (isset($results[$id][$name]) == false OR !is_array($results[$id][$name])) {

				$results[$id][$name] = array();

			}

			

			// Add row to owner

			$results[$id][$name][] = $row;	

		}



		// Return keys

		$newresults = array();

		$i = 0;

		foreach ($results as $row) {

			$key = $keys[$i];

			$newresults[$key] = $row;

			$i++;

		}

		$results = $newresults;



		return $results;

	}



	function _joinOne2One ($results) {

		// Get ID's from results

		$ids_list = array();

		foreach ($results as $row) {

			$ids_list[] = $row[$this->_owner_field];

		}

		$ids_list = array_unique($ids_list);

		$ids_list = implode("', '", $ids_list);



		// Now select rows from other table

		$this->_other_obj->where = "`" . $this->_other_field . "` IN ('" . $ids_list . "')";

		$other = $this->_other_obj->select($this->_other_field);



		// Now match each result up

		$newresults = array();

		foreach ($results as $key => $row) {

			// Get id of row

			$id = $row[$this->_owner_field];



			// Does other row exist?

			if (isset($other[$id])) {

				// Copy other row

				$row[$this->_owner_field] = $other[$id];

			}



			$newresults[$key] = $row;

		}

		$results = $newresults;



		return $results;

	}



	/**#@-*/



}





?>