<?php
/*
 * 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.doctrine-project.org>.
 */

namespace Doctrine\ORM\Mapping\Driver;

use Doctrine\Common\Cache\ArrayCache,
    Doctrine\Common\Annotations\AnnotationReader,
    Doctrine\DBAL\Schema\AbstractSchemaManager,
    Doctrine\DBAL\Schema\SchemaException,
    Doctrine\ORM\Mapping\ClassMetadataInfo,
    Doctrine\ORM\Mapping\MappingException,
    Doctrine\Common\Util\Inflector,
    Doctrine\Common\Persistence\Mapping\Driver;

/**
 * The DatabaseDriver reverse engineers the mapping metadata from a database.
 *
 * @license http://www.opensource.org/licenses/lgpl-license.php LGPL
 * @link    www.doctrine-project.org
 * @since   2.0
 * @author  Guilherme Blanco <guilhermeblanco@hotmail.com>
 * @author  Jonathan Wage <jonwage@gmail.com>
 * @author  Benjamin Eberlei <kontakt@beberlei.de>
 */
class DatabaseDriver implements Driver
{
    /**
     * @var AbstractSchemaManager
     */
    private $_sm;

    /**
     * @var array
     */
    private $tables = null;

    private $classToTableNames = array();

    /**
     * @var array
     */
    private $manyToManyTables = array();
    
    /**
     * Initializes a new AnnotationDriver that uses the given AnnotationReader for reading
     * docblock annotations.
     * 
     * @param AnnotationReader $reader The AnnotationReader to use.
     */
    public function __construct(AbstractSchemaManager $schemaManager)
    {
        $this->_sm = $schemaManager;
    }

    private function reverseEngineerMappingFromDatabase()
    {
        if ($this->tables !== null) {
            return;
        }

        foreach ($this->_sm->listTableNames() as $tableName) {
            $tables[$tableName] = $this->_sm->listTableDetails($tableName);
        }

        $this->tables = array();
        foreach ($tables AS $tableName => $table) {
            /* @var $table Table */
            if ($this->_sm->getDatabasePlatform()->supportsForeignKeyConstraints()) {
                $foreignKeys = $table->getForeignKeys();
            } else {
                $foreignKeys = array();
            }

            $allForeignKeyColumns = array();
            foreach ($foreignKeys AS $foreignKey) {
                $allForeignKeyColumns = array_merge($allForeignKeyColumns, $foreignKey->getLocalColumns());
            }
            
            $pkColumns = $table->getPrimaryKey()->getColumns();
            sort($pkColumns);
            sort($allForeignKeyColumns);

            if ($pkColumns == $allForeignKeyColumns) {
                if (count($table->getForeignKeys()) > 2) {
                    throw new \InvalidArgumentException("ManyToMany table '" . $tableName . "' with more or less than two foreign keys are not supported by the Database Reverese Engineering Driver.");
                }

                $this->manyToManyTables[$tableName] = $table;
            } else {
                // lower-casing is necessary because of Oracle Uppercase Tablenames,
                // assumption is lower-case + underscore separated.
                $className = Inflector::classify(strtolower($tableName));
                $this->tables[$tableName] = $table;
                $this->classToTableNames[$className] = $tableName;
            }
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function loadMetadataForClass($className, \Doctrine\Common\Persistence\Mapping\ClassMetadata $metadata)
    {
        $this->reverseEngineerMappingFromDatabase();

        if (!isset($this->classToTableNames[$className])) {
            throw new \InvalidArgumentException("Unknown class " . $className);
        }

        $tableName = $this->classToTableNames[$className];

        $metadata->name = $className;
        $metadata->table['name'] = $tableName;

        $columns = $this->tables[$tableName]->getColumns();
        $indexes = $this->tables[$tableName]->getIndexes();
        try {
            $primaryKeyColumns = $this->tables[$tableName]->getPrimaryKey()->getColumns();
        } catch(SchemaException $e) {
            $primaryKeyColumns = array();
        }
        
        if ($this->_sm->getDatabasePlatform()->supportsForeignKeyConstraints()) {
            $foreignKeys = $this->tables[$tableName]->getForeignKeys();
        } else {
            $foreignKeys = array();
        }

        $allForeignKeyColumns = array();
        foreach ($foreignKeys AS $foreignKey) {
            $allForeignKeyColumns = array_merge($allForeignKeyColumns, $foreignKey->getLocalColumns());
        }

        $ids = array();
        $fieldMappings = array();
        foreach ($columns as $column) {
            $fieldMapping = array();
            if ($primaryKeyColumns && in_array($column->getName(), $primaryKeyColumns)) {
                $fieldMapping['id'] = true;
            } else if (in_array($column->getName(), $allForeignKeyColumns)) {
                continue;
            }

            $fieldMapping['fieldName'] = Inflector::camelize(strtolower($column->getName()));
            $fieldMapping['columnName'] = $column->getName();
            $fieldMapping['type'] = strtolower((string) $column->getType());

            if ($column->getType() instanceof \Doctrine\DBAL\Types\StringType) {
                $fieldMapping['length'] = $column->getLength();
                $fieldMapping['fixed'] = $column->getFixed();
            } else if ($column->getType() instanceof \Doctrine\DBAL\Types\IntegerType) {
                $fieldMapping['unsigned'] = $column->getUnsigned();
            }
            $fieldMapping['nullable'] = $column->getNotNull() ? false : true;

            if (isset($fieldMapping['id'])) {
                $ids[] = $fieldMapping;
            } else {
                $fieldMappings[] = $fieldMapping;
            }
        }

        if ($ids) {
            if (count($ids) == 1) {
                $metadata->setIdGeneratorType(ClassMetadataInfo::GENERATOR_TYPE_AUTO);
            }

            foreach ($ids as $id) {
                $metadata->mapField($id);
            }
        }

        foreach ($fieldMappings as $fieldMapping) {
            $metadata->mapField($fieldMapping);
        }

        foreach ($this->manyToManyTables AS $manyTable) {
            foreach ($manyTable->getForeignKeys() AS $foreignKey) {
                if (strtolower($tableName) == strtolower($foreignKey->getForeignTableName())) {
                    $myFk = $foreignKey;
                    foreach ($manyTable->getForeignKeys() AS $foreignKey) {
                        if ($foreignKey != $myFk) {
                            $otherFk = $foreignKey;
                            break;
                        }
                    }

                    $localColumn = current($myFk->getColumns());
                    $associationMapping = array();
                    $associationMapping['fieldName'] = Inflector::camelize(str_replace('_id', '', strtolower(current($otherFk->getColumns()))));
                    $associationMapping['targetEntity'] = Inflector::classify(strtolower($otherFk->getForeignTableName()));
                    if (current($manyTable->getColumns())->getName() == $localColumn) {
                        $associationMapping['inversedBy'] = Inflector::camelize(str_replace('_id', '', strtolower(current($myFk->getColumns()))));
                        $associationMapping['joinTable'] = array(
                            'name' => strtolower($manyTable->getName()),
                            'joinColumns' => array(),
                            'inverseJoinColumns' => array(),
                        );

                        $fkCols = $myFk->getForeignColumns();
                        $cols = $myFk->getColumns();
                        for ($i = 0; $i < count($cols); $i++) {
                            $associationMapping['joinTable']['joinColumns'][] = array(
                                'name' => $cols[$i],
                                'referencedColumnName' => $fkCols[$i],
                            );
                        }

                        $fkCols = $otherFk->getForeignColumns();
                        $cols = $otherFk->getColumns();
                        for ($i = 0; $i < count($cols); $i++) {
                            $associationMapping['joinTable']['inverseJoinColumns'][] = array(
                                'name' => $cols[$i],
                                'referencedColumnName' => $fkCols[$i],
                            );
                        }
                    } else {
                        $associationMapping['mappedBy'] = Inflector::camelize(str_replace('_id', '', strtolower(current($myFk->getColumns()))));
                    }
                    $metadata->mapManyToMany($associationMapping);
                    break;
                }
            }
        }

        foreach ($foreignKeys as $foreignKey) {
            $foreignTable = $foreignKey->getForeignTableName();
            $cols = $foreignKey->getColumns();
            $fkCols = $foreignKey->getForeignColumns();

            $localColumn = current($cols);
            $associationMapping = array();
            $associationMapping['fieldName'] = Inflector::camelize(str_replace('_id', '', strtolower($localColumn)));
            $associationMapping['targetEntity'] = Inflector::classify($foreignTable);

            for ($i = 0; $i < count($cols); $i++) {
                $associationMapping['joinColumns'][] = array(
                    'name' => $cols[$i],
                    'referencedColumnName' => $fkCols[$i],
                );
            }
            $metadata->mapManyToOne($associationMapping);
        }
    }

    /**
     * {@inheritdoc}
     */
    public function isTransient($className)
    {
        return true;
    }

    /**
     * Return all the class names supported by this driver.
     *
     * IMPORTANT: This method must return an array of class not tables names.
     *
     * @return array
     */
    public function getAllClassNames()
    {
        $this->reverseEngineerMappingFromDatabase();

        return array_keys($this->classToTableNames);
    }
}