Session.php

<?php
/* 
 *  $Id$
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information, see
 * <http://www.phpdoctrine.com>.
 */

/**
 * Doctrine_Session
 *
 * @package     Doctrine ORM
 * @url         www.phpdoctrine.com
 * @license     LGPL
 */
abstract class Doctrine_Session extends Doctrine_Configurable implements Countable, IteratorAggregate {
    /**
     * Doctrine_Session is in open state when it is opened and there are no active transactions
     */
    const STATE_OPEN        = 0;
    /**
     * Doctrine_Session is in closed state when it is closed
     */
    const STATE_CLOSED      = 1;
    /**
     * Doctrine_Session is in active state when it has one active transaction
     */
    const STATE_ACTIVE      = 2;
    /**
     * Doctrine_Session is in busy state when it has multiple active transactions
     */
    const STATE_BUSY        = 3;
    /**
     * @var $dbh                            the database handle
     */
    private $dbh;
    /**
     * @see Doctrine_Session::STATE_* constants
     * @var boolean $state                  the current state of the session
     */
    private $state              = 0;
    /**
     * @var integer $transaction_level      the nesting level of transactions, used by transaction methods
     */
    private $transaction_level  = 0;
    /**
     * @var array $tables                   an array containing all the initialized Doctrine_Table objects
     *                                      keys representing Doctrine_Table component names and values as Doctrine_Table objects
     */
    protected $tables           = array();
    /**
     * @var Doctrine_Validator $validator   transaction validator
     */
    protected $validator;
    /**
     * @var array $update                   two dimensional pending update list, the records in
     *                                      this list will be updated when transaction is committed
     */
    protected $update           = array();
    /**
     * @var array $insert                   two dimensional pending insert list, the records in
     *                                      this list will be inserted when transaction is committed
     */
    protected $insert           = array();
    /**
     * @var array $delete                   two dimensional pending delete list, the records in
     *                                      this list will be deleted when transaction is committed
     */
    protected $delete           = array();




    /**
     * the constructor
     *
     * @param Doctrine_Manager $manager     the manager object
     * @param PDO $pdo                      the database handler
     */
    public function __construct(Doctrine_Manager $manager,PDO $pdo) {
        $this->dbh   = $pdo;
        $this->state = Doctrine_Session::STATE_OPEN;

        $this->setParent($manager);

        $this->dbh->setAttribute(PDO::ATTR_CASE, PDO::CASE_NATURAL);
        $this->dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);   

        $this->getAttribute(Doctrine::ATTR_LISTENER)->onOpen($this);
    }
    /**
     * returns the state of this session
     *
     * @see Doctrine_Session::STATE_* constants
     * @return integer          the session state
     */
    public function getState() {
        return $this->state;
    }
    /**
     * returns the manager that created this session
     *
     * @return Doctrine_Manager
     */
    public function getManager() {
        return $this->getParent();
    }
    /**
     * returns the database handler of which this session uses
     *
     * @return object PDO       the database handler
     */
    public function getDBH() {
        return $this->dbh;
    }
    /**
     * query
     * queries the database with Doctrine Query Language
     *
     * @param string $query         DQL query
     * @param array $params         query parameters
     */
    final public function query($query,array $params = array()) {
        $parser = new Doctrine_Query($this);

        return $parser->query($query, $params);
    }
    /**
     * queries the database with limit and offset
     * added to the query and returns a PDOStatement object
     *
     * @param string $query
     * @param integer $limit
     * @param integer $offset
     * @return PDOStatement
     */
    public function select($query,$limit = 0,$offset = 0) {
        if($limit > 0 || $offset > 0)
            $query = $this->modifyLimitQuery($query,$limit,$offset);

        return $this->dbh->query($query);
    }
    /**
     * @param string $query     sql query
     * @param array $params     query parameters
     *
     * @return PDOStatement
     */
    public function execute($query, array $params = array()) {
        if( ! empty($params)) {
            $stmt = $this->dbh->prepare($query);
            $stmt->execute($params);
            return $stmt;
        } else {
            return $this->dbh->query($query);
        }
    }
    /**
     * whether or not this session has table $name initialized
     *
     * @param $mixed $name
     * @return boolean
     */
    public function hasTable($name) {
        return isset($this->tables[$name]);
    }
    /**
     * returns a table object for given component name
     *
     * @param string $name              component name
     * @return object Doctrine_Table
     */
    public function getTable($name) {
        if(isset($this->tables[$name]))
            return $this->tables[$name];

        $class = $name."Table";

        if(class_exists($class) && in_array("Doctrine_Table", class_parents($class))) {
            return new $class($name);
        } else {

            return new Doctrine_Table($name);
        }
    }
    /**
     * returns an array of all initialized tables
     *
     * @return array
     */
    public function getTables() {
        return $this->tables;
    }
    /**
     * returns an iterator that iterators through all 
     * initialized table objects
     *
     * @return ArrayIterator
     */
    public function getIterator() {
        return new ArrayIterator($this->tables);
    }
    /**
     * returns the count of initialized table objects
     *
     * @return integer
     */
    public function count() {
        return count($this->tables);
    }
    /**
     * @param $objTable             a Doctrine_Table object to be added into registry
     * @return boolean
     */
    public function addTable(Doctrine_Table $objTable) {
        $name = $objTable->getComponentName();

        if(isset($this->tables[$name]))
            return false;

        $this->tables[$name] = $objTable;
        return true;
    }
    /**
     * creates a record
     *
     * create                       creates a record
     * @param string $name          component name
     * @return Doctrine_Record      Doctrine_Record object
     */
    public function create($name) {
        return $this->getTable($name)->create();
    }


    /**
     * buildFlushTree
     * builds a flush tree that is used in transactions
     *
     * @return array
     */
    public function buildFlushTree(array $tables) {
        $tree = array();
        foreach($tables as $k => $table) {
            $k = $k.$table;
            if( ! ($table instanceof Doctrine_Table))
                $table = $this->getTable($table);

            $nm     = $table->getComponentName();

            $index  = array_search($nm,$tree);
            if($index === false) {
                $tree[] = $nm;
                $index  = max(array_keys($tree));

                //print "$k -- adding <b>$nm</b>...<br \>";
            }

            $rels = $table->getRelations();
            
            // group relations
            
            foreach($rels as $key => $rel) {
                if($rel instanceof Doctrine_ForeignKey) {
                    unset($rels[$key]);
                    array_unshift($rels, $rel);
                }
            }

            foreach($rels as $rel) {
                $name   = $rel->getTable()->getComponentName();
                $index2 = array_search($name,$tree);
                $type   = $rel->getType();

                // skip self-referenced relations
                if($name === $nm)
                    continue;

                if($rel instanceof Doctrine_ForeignKey) {
                    if($index2 !== false) {
                        if($index2 >= $index)
                            continue;

                        unset($tree[$index]);
                        array_splice($tree,$index2,0,$nm);
                        $index = $index2;
                        
                        //print "$k -- pushing $nm into $index2...<br \>";

                    } else {
                        $tree[] = $name;
                        //print "$k -- adding $nm :$name...<br>";
                    }

                } elseif($rel instanceof Doctrine_LocalKey) {
                    if($index2 !== false) {
                        if($index2 <= $index)
                            continue;

                        unset($tree[$index2]);
                        array_splice($tree,$index,0,$name);

                        //print "$k -- pushing $name into <b>$index</b>...<br \>";

                    } else {
                        //array_splice($tree, $index, 0, $name);
                        array_unshift($tree,$name);
                        $index++;

                        //print "$k -- pushing <b>$name</b> into 0...<br \>";
                    }
                } elseif($rel instanceof Doctrine_Association) {
                    $t = $rel->getAssociationFactory();
                    $n = $t->getComponentName();
                    
                    if($index2 !== false)
                        unset($tree[$index2]);
                    
                    array_splice($tree,$index, 0,$name);
                    $index++;

                    $index3 = array_search($n,$tree);

                    if($index3 !== false) {
                        if($index3 >= $index)
                            continue;

                        unset($tree[$index]);
                        array_splice($tree,$index3,0,$n);
                        $index = $index2;

                        //print "$k -- pushing $nm into $index3...<br \>";

                    } else {
                        $tree[] = $n;
                        //print "$k -- adding $nm :$name...<br>";
                    }
                }
                //print_r($tree);
            }
            //print_r($tree);

        }
        return array_values($tree);
    }

    /**
     * flush                        
     * saves all the records from all tables
     * this operation is isolated using a transaction
     *
     * @return void
     */
    public function flush() {
        $this->beginTransaction();
        $this->saveAll();
        $this->commit();
    }
    /**
     * saveAll                      
     * saves all the records from all tables
     *
     * @return void
     */
    private function saveAll() {
        $tree = $this->buildFlushTree($this->tables);

        foreach($tree as $name) {
            $table = $this->tables[$name];

            foreach($table->getRepository() as $record) {
                $this->save($record);
            }
        }
        foreach($tree as $name) {
            $table = $this->tables[$name];
            foreach($table->getRepository() as $record) {
                $record->saveAssociations();
            }
        }
    }
    /**
     * clear
     * clears all repositories
     *
     * @return void
     */
    public function clear() {
        foreach($this->tables as $k => $table) {
            $table->getRepository()->evictAll();
            $table->clear();
        }
    }
    /**
     * @return void
     */
    public function evictTables() {
        $this->tables = array();
    }
    /**
     * close
     * closes the session
     *
     * @return void
     */
    public function close() {
        $this->getAttribute(Doctrine::ATTR_LISTENER)->onPreClose($this);

        $this->clear();
        $this->state = Doctrine_Session::STATE_CLOSED;
        
        $this->getAttribute(Doctrine::ATTR_LISTENER)->onClose($this);
    }
    /**
     * get the current transaction nesting level
     *
     * @return integer
     */
    public function getTransactionLevel() {
        return $this->transaction_level;
    }
    /**
     * beginTransaction
     * starts a new transaction
     * @return void
     */
    public function beginTransaction() {
        if($this->transaction_level == 0) {

            if($this->getAttribute(Doctrine::ATTR_LOCKMODE) == Doctrine::LOCK_PESSIMISTIC) {
                $this->getAttribute(Doctrine::ATTR_LISTENER)->onPreTransactionBegin($this);
                $this->dbh->beginTransaction();
                $this->getAttribute(Doctrine::ATTR_LISTENER)->onTransactionBegin($this);
            }
            $this->state  = Doctrine_Session::STATE_ACTIVE;
        } else {
            $this->state = Doctrine_Session::STATE_BUSY;
        }
        $this->transaction_level++;
    }
    /**
     * commits the current transaction
     * if lockmode is optimistic this method starts a transaction
     * and commits it instantly
     *
     * @return void
     */
    public function commit() {

        $this->transaction_level--;
    
        if($this->transaction_level == 0) {

    
            if($this->getAttribute(Doctrine::ATTR_LOCKMODE) == Doctrine::LOCK_OPTIMISTIC) {
                $this->getAttribute(Doctrine::ATTR_LISTENER)->onPreTransactionBegin($this);
    
                $this->dbh->beginTransaction();
    
                $this->getAttribute(Doctrine::ATTR_LISTENER)->onTransactionBegin($this);
            }
    
            if($this->getAttribute(Doctrine::ATTR_VLD))
                $this->validator = new Doctrine_Validator();

            try {
                
                $this->bulkInsert();
                $this->bulkUpdate();
                $this->bulkDelete();

                if($this->getAttribute(Doctrine::ATTR_VLD)) {
                    if($this->validator->hasErrors()) {
                        $this->rollback();
                        throw new Doctrine_Validator_Exception($this->validator);
                    }
                }

                $this->dbh->commit();

            } catch(PDOException $e) {
                $this->rollback();

                throw new Doctrine_Exception($e->__toString());
            }

            $this->getAttribute(Doctrine::ATTR_LISTENER)->onTransactionCommit($this);

            $this->delete = array();
            $this->state  = Doctrine_Session::STATE_OPEN;
    
            $this->validator = null;
    
        } elseif($this->transaction_level == 1)
            $this->state = Doctrine_Session::STATE_ACTIVE;
    }
    /**
     * rollback
     * rolls back all transactions
     *
     * this method also listens to onPreTransactionRollback and onTransactionRollback
     * eventlisteners
     *
     * @return void
     */
    public function rollback() {
        $this->getAttribute(Doctrine::ATTR_LISTENER)->onPreTransactionRollback($this);

        $this->transaction_level = 0;
        $this->dbh->rollback();
        $this->state = Doctrine_Session::STATE_OPEN;

        $this->getAttribute(Doctrine::ATTR_LISTENER)->onTransactionRollback($this);
    }
    /**
     * bulkInsert
     * inserts all the objects in the pending insert list into database
     * @return void
     */
    public function bulkInsert() {
        if(empty($this->insert))
            return false;

        foreach($this->insert as $name => $inserts) {
            if( ! isset($inserts[0]))
                continue;

            $record    = $inserts[0];
            $table     = $record->getTable();
            $seq       = $table->getSequenceName();

            $increment = false;
            $keys      = $table->getPrimaryKeys();
            $id        = null;

            if(count($keys) == 1 && $keys[0] == $table->getIdentifier()) {
                $increment = true;
            }

            foreach($inserts as $k => $record) {
                $table->getAttribute(Doctrine::ATTR_LISTENER)->onPreSave($record);
                // listen the onPreInsert event
                $table->getAttribute(Doctrine::ATTR_LISTENER)->onPreInsert($record);


                $this->insert($record);
                if($increment) {
                    if($k == 0) {
                        // record uses auto_increment column

                        $id = $this->dbh->lastInsertID();

                        if( ! $id)
                            $id = $table->getMaxIdentifier();
                    }
    
                    $record->assignIdentifier($id);
                    $id++;
                } else
                    $record->assignIdentifier(true);

                // listen the onInsert event
                $table->getAttribute(Doctrine::ATTR_LISTENER)->onInsert($record);

                $table->getAttribute(Doctrine::ATTR_LISTENER)->onSave($record);
            }
        }
        $this->insert = array();
        return true;
    }
    /**
     * returns maximum identifier values
     *
     * @param array $names          an array of component names
     * @return array
     */   
    public function getMaximumValues(array $names) {
        $values = array();
        foreach($names as $name) {
            $table     = $this->tables[$name];
            $keys      = $table->getPrimaryKeys();
            $tablename = $table->getTableName();

            if(count($keys) == 1 && $keys[0] == $table->getIdentifier()) {
                // record uses auto_increment column

                $sql    = "SELECT MAX(".$table->getIdentifier().") FROM ".$tablename;
                $stmt   = $this->dbh->query($sql);
                $data   = $stmt->fetch(PDO::FETCH_NUM);
                $values[$tablename] = $data[0];

                $stmt->closeCursor();
            }
        }
        return $values;
    }
    /**
     * bulkUpdate
     * updates all objects in the pending update list
     *
     * @return void
     */
    public function bulkUpdate() {
        foreach($this->update as $name => $updates) {
            $ids = array();

            foreach($updates as $k => $record) {
                $record->getTable()->getAttribute(Doctrine::ATTR_LISTENER)->onPreSave($record);
                // listen the onPreUpdate event
                $record->getTable()->getAttribute(Doctrine::ATTR_LISTENER)->onPreUpdate($record);

                $this->update($record);
                // listen the onUpdate event
                $record->getTable()->getAttribute(Doctrine::ATTR_LISTENER)->onUpdate($record);

                $record->getTable()->getAttribute(Doctrine::ATTR_LISTENER)->onSave($record);
            }
        }
        $this->update = array();
    }
    /**
     * bulkDelete
     * deletes all records from the pending delete list
     *
     * @return void
     */
    public function bulkDelete() {
        foreach($this->delete as $name => $deletes) {
            $record = false;
            $ids    = array();
            foreach($deletes as $k => $record) {
                $ids[] = $record->getIncremented();
                $record->assignIdentifier(false);
            }
            if($record instanceof Doctrine_Record) {
                $table  = $record->getTable();

                $params  = substr(str_repeat("?, ",count($ids)),0,-2);
                $query   = "DELETE FROM ".$record->getTable()->getTableName()." WHERE ".$table->getIdentifier()." IN(".$params.")";
                $this->execute($query,$ids);

                $record->getTable()->getCache()->deleteMultiple($ids);
            }
        }
        $this->delete = array();
    }
    /**
     * saves a collection
     *
     * @param Doctrine_Collection $coll
     * @return void
     */
    public function saveCollection(Doctrine_Collection $coll) {
        $this->beginTransaction();

        foreach($coll as $key=>$record):
                $record->save();
        endforeach;

        $this->commit();
    }
    /**
     * deletes all records from collection
     *
     * @param Doctrine_Collection $coll
     * @return void
     */
    public function deleteCollection(Doctrine_Collection $coll) {
        $this->beginTransaction();
        foreach($coll as $k=>$record) {
            $record->delete();
        }
        $this->commit();
    }
    /**
     * saves the given record
     *
     * @param Doctrine_Record $record
     * @return void
     */
    public function save(Doctrine_Record $record) {
        switch($record->getState()):
            case Doctrine_Record::STATE_TDIRTY:
                $this->addInsert($record);
            break;
            case Doctrine_Record::STATE_DIRTY:
            case Doctrine_Record::STATE_PROXY:
                $this->addUpdate($record);
            break;
            case Doctrine_Record::STATE_CLEAN:
            case Doctrine_Record::STATE_TCLEAN:
                // do nothing
            break;
        endswitch;
    }
    /**
     * saves all related records to $record
     *
     * @param Doctrine_Record $record
     */
    final public function saveRelated(Doctrine_Record $record) {
        $saveLater = array();
        foreach($record->getReferences() as $k=>$v) {
            $fk = $record->getTable()->getRelation($k);
            if($fk instanceof Doctrine_ForeignKey ||
               $fk instanceof Doctrine_LocalKey) {
                switch($fk->getType()):
                    case Doctrine_Relation::ONE_COMPOSITE:
                    case Doctrine_Relation::MANY_COMPOSITE:
                        $local = $fk->getLocal();
                        $foreign = $fk->getForeign();

                        if($record->getTable()->hasPrimaryKey($fk->getLocal())) {
                            switch($record->getState()):
                                case Doctrine_Record::STATE_TDIRTY:
                                case Doctrine_Record::STATE_TCLEAN:
                                    $saveLater[$k] = $fk;
                                break;
                                case Doctrine_Record::STATE_CLEAN:
                                case Doctrine_Record::STATE_DIRTY:
                                    $v->save();    
                                break;
                            endswitch;
                        } else {
                            // ONE-TO-ONE relationship
                            $obj = $record->get($fk->getTable()->getComponentName());

                            if($obj->getState() != Doctrine_Record::STATE_TCLEAN)
                                $obj->save();

                        }
                    break;
                endswitch;
            } elseif($fk instanceof Doctrine_Association) {
                $v->save();
            }
        }
        return $saveLater;
    }
    /**
     * updates the given record
     *
     * @param Doctrine_Record $record
     * @return boolean
     */
    private function update(Doctrine_Record $record) {
        $array = $record->getPrepared();

        if(empty($array))
            return false;

        $set   = array();
        foreach($array as $name => $value):
                $set[] = $name." = ?";

                if($value instanceof Doctrine_Record) {
                    switch($value->getState()):
                        case Doctrine_Record::STATE_TCLEAN:
                        case Doctrine_Record::STATE_TDIRTY:
                            $record->save();
                        default:
                            $array[$name] = $value->getIncremented();
                            $record->set($name, $value->getIncremented());
                    endswitch;
                }
        endforeach;

        if(isset($this->validator)) {
            if( ! $this->validator->validateRecord($record)) {
                return false;
            }
        }

        $params   = array_values($array);
        $id       = $record->obtainIdentifier();


        if( ! is_array($id))
            $id = array($id);

        $id     = array_values($id);
        $params = array_merge($params, $id);


        $sql  = "UPDATE ".$record->getTable()->getTableName()." SET ".implode(", ",$set)." WHERE ".implode(" = ? AND ",$record->getTable()->getPrimaryKeys())." = ?";

        $stmt = $this->dbh->prepare($sql);
        $stmt->execute($params);

        $record->assignIdentifier(true);

        return true;
    }
    /**
     * inserts a record into database
     *
     * @param Doctrine_Record $record
     * @return boolean
     */
    private function insert(Doctrine_Record $record) {
        $array = $record->getPrepared();

        if(empty($array))
            return false;

        $seq = $record->getTable()->getSequenceName();

        if( ! empty($seq)) {
            $id             = $this->getNextID($seq);
            $name           = $record->getTable()->getIdentifier();
            $array[$name]   = $id;
        }

        if(isset($this->validator)) {
            if( ! $this->validator->validateRecord($record)) {
                return false;
            }
        }

        $strfields = join(", ", array_keys($array));
        $strvalues = substr(str_repeat("?, ",count($array)),0,-2);

        $sql  = "INSERT INTO ".$record->getTable()->getTableName()." (".$strfields.") VALUES (".$strvalues.")";

        $stmt = $this->dbh->prepare($sql);

        $stmt->execute(array_values($array));

        return true;
    }
    /**
     * deletes all related composites
     * this method is always called internally when a record is deleted
     *
     * @return void
     */
    final public function deleteComposites(Doctrine_Record $record) {
        foreach($record->getTable()->getRelations() as $fk) {
            switch($fk->getType()):
                case Doctrine_Relation::ONE_COMPOSITE:
                case Doctrine_Relation::MANY_COMPOSITE:
                    $obj = $record->get($record->getTable()->getAlias($fk->getTable()->getComponentName()));
                    $obj->delete();
                break;
            endswitch;
        }
    }
    /**
     * deletes this data access object and all the related composites
     * this operation is isolated by a transaction
     * 
     * this event can be listened by the onPreDelete and onDelete listeners
     *
     * @return boolean      true on success, false on failure
     */
    final public function delete(Doctrine_Record $record) {
        switch($record->getState()):
            case Doctrine_Record::STATE_PROXY:
            case Doctrine_Record::STATE_CLEAN:
            case Doctrine_Record::STATE_DIRTY:
                $this->beginTransaction();

                $this->deleteComposites($record);
                $this->addDelete($record);

                $this->commit();
                return true;
            break;
            default:
                return false;
        endswitch;    
    }
    /**
     * adds record into pending insert list
     * @param Doctrine_Record $record
     */
    public function addInsert(Doctrine_Record $record) {
        $name = $record->getTable()->getComponentName();
        $this->insert[$name][] = $record;
    }
    /**
     * adds record into penging update list
     * @param Doctrine_Record $record
     */
    public function addUpdate(Doctrine_Record $record) {
        $name = $record->getTable()->getComponentName();
        $this->update[$name][] = $record;
    }
    /**
     * adds record into pending delete list
     * @param Doctrine_Record $record
     */
    public function addDelete(Doctrine_Record $record) {
        $name = $record->getTable()->getComponentName();
        $this->delete[$name][] = $record;
    }
    /**
     * returns the pending insert list
     *
     * @return array
     */
    public function getInserts() {
        return $this->insert;
    }
    /**
     * returns the pending update list
     *
     * @return array
     */
    public function getUpdates() {
        return $this->update;
    }
    /**
     * returns the pending delete list
     *
     * @return array
     */
    public function getDeletes() {
        return $this->delete;
    }

    /**
     * returns a string representation of this object
     * @return string
     */
    public function __toString() {
        return Doctrine_Lib::getSessionAsString($this);
    }
}