<?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\Cache\Adapter;

use Doctrine\DBAL\Connection;
use Doctrine\DBAL\Driver\ServerInfoAwareConnection;
use Doctrine\DBAL\DriverManager;
use Doctrine\DBAL\Exception as DBALException;
use Doctrine\DBAL\Exception\TableNotFoundException;
use Doctrine\DBAL\ParameterType;
use Doctrine\DBAL\Schema\Schema;
use Symfony\Component\Cache\Exception\InvalidArgumentException;
use Symfony\Component\Cache\Marshaller\DefaultMarshaller;
use Symfony\Component\Cache\Marshaller\MarshallerInterface;
use Symfony\Component\Cache\PruneableInterface;

class DoctrineDbalAdapter extends AbstractAdapter implements PruneableInterface
{
    protected $maxIdLength = 255;

    private $marshaller;
    private $conn;
    private $platformName;
    private $serverVersion;
    private $table = 'cache_items';
    private $idCol = 'item_id';
    private $dataCol = 'item_data';
    private $lifetimeCol = 'item_lifetime';
    private $timeCol = 'item_time';
    private $namespace;

    /**
     * You can either pass an existing database Doctrine DBAL Connection or
     * a DSN string that will be used to connect to the database.
     *
     * The cache table is created automatically when possible.
     * Otherwise, use the createTable() method.
     *
     * List of available options:
     *  * db_table: The name of the table [default: cache_items]
     *  * db_id_col: The column where to store the cache id [default: item_id]
     *  * db_data_col: The column where to store the cache data [default: item_data]
     *  * db_lifetime_col: The column where to store the lifetime [default: item_lifetime]
     *  * db_time_col: The column where to store the timestamp [default: item_time]
     *
     * @param Connection|string $connOrDsn
     *
     * @throws InvalidArgumentException When namespace contains invalid characters
     */
    public function __construct($connOrDsn, string $namespace = '', int $defaultLifetime = 0, array $options = [], MarshallerInterface $marshaller = null)
    {
        if (isset($namespace[0]) && preg_match('#[^-+.A-Za-z0-9]#', $namespace, $match)) {
            throw new InvalidArgumentException(sprintf('Namespace contains "%s" but only characters in [-+.A-Za-z0-9] are allowed.', $match[0]));
        }

        if ($connOrDsn instanceof Connection) {
            $this->conn = $connOrDsn;
        } elseif (\is_string($connOrDsn)) {
            if (!class_exists(DriverManager::class)) {
                throw new InvalidArgumentException(sprintf('Failed to parse the DSN "%s". Try running "composer require doctrine/dbal".', $connOrDsn));
            }
            $this->conn = DriverManager::getConnection(['url' => $connOrDsn]);
        } else {
            throw new \TypeError(sprintf('Argument 1 passed to "%s()" must be "%s" or string, "%s" given.', __METHOD__, Connection::class, get_debug_type($connOrDsn)));
        }

        $this->table = $options['db_table'] ?? $this->table;
        $this->idCol = $options['db_id_col'] ?? $this->idCol;
        $this->dataCol = $options['db_data_col'] ?? $this->dataCol;
        $this->lifetimeCol = $options['db_lifetime_col'] ?? $this->lifetimeCol;
        $this->timeCol = $options['db_time_col'] ?? $this->timeCol;
        $this->namespace = $namespace;
        $this->marshaller = $marshaller ?? new DefaultMarshaller();

        parent::__construct($namespace, $defaultLifetime);
    }

    /**
     * Creates the table to store cache items which can be called once for setup.
     *
     * Cache ID are saved in a column of maximum length 255. Cache data is
     * saved in a BLOB.
     *
     * @throws DBALException When the table already exists
     */
    public function createTable()
    {
        $schema = new Schema();
        $this->addTableToSchema($schema);

        foreach ($schema->toSql($this->conn->getDatabasePlatform()) as $sql) {
            $this->conn->executeStatement($sql);
        }
    }

    /**
     * {@inheritdoc}
     */
    public function configureSchema(Schema $schema, Connection $forConnection): void
    {
        // only update the schema for this connection
        if ($forConnection !== $this->conn) {
            return;
        }

        if ($schema->hasTable($this->table)) {
            return;
        }

        $this->addTableToSchema($schema);
    }

    /**
     * {@inheritdoc}
     */
    public function prune(): bool
    {
        $deleteSql = "DELETE FROM $this->table WHERE $this->lifetimeCol + $this->timeCol <= ?";
        $params = [time()];
        $paramTypes = [ParameterType::INTEGER];

        if ('' !== $this->namespace) {
            $deleteSql .= " AND $this->idCol LIKE ?";
            $params[] = sprintf('%s%%', $this->namespace);
            $paramTypes[] = ParameterType::STRING;
        }

        try {
            $this->conn->executeStatement($deleteSql, $params, $paramTypes);
        } catch (TableNotFoundException $e) {
        }

        return true;
    }

    /**
     * {@inheritdoc}
     */
    protected function doFetch(array $ids): iterable
    {
        $now = time();
        $expired = [];

        $sql = "SELECT $this->idCol, CASE WHEN $this->lifetimeCol IS NULL OR $this->lifetimeCol + $this->timeCol > ? THEN $this->dataCol ELSE NULL END FROM $this->table WHERE $this->idCol IN (?)";
        $result = $this->conn->executeQuery($sql, [
            $now,
            $ids,
        ], [
            ParameterType::INTEGER,
            Connection::PARAM_STR_ARRAY,
        ])->iterateNumeric();

        foreach ($result as $row) {
            if (null === $row[1]) {
                $expired[] = $row[0];
            } else {
                yield $row[0] => $this->marshaller->unmarshall(\is_resource($row[1]) ? stream_get_contents($row[1]) : $row[1]);
            }
        }

        if ($expired) {
            $sql = "DELETE FROM $this->table WHERE $this->lifetimeCol + $this->timeCol <= ? AND $this->idCol IN (?)";
            $this->conn->executeStatement($sql, [
                $now,
                $expired,
            ], [
                ParameterType::INTEGER,
                Connection::PARAM_STR_ARRAY,
            ]);
        }
    }

    /**
     * {@inheritdoc}
     */
    protected function doHave(string $id): bool
    {
        $sql = "SELECT 1 FROM $this->table WHERE $this->idCol = ? AND ($this->lifetimeCol IS NULL OR $this->lifetimeCol + $this->timeCol > ?)";
        $result = $this->conn->executeQuery($sql, [
            $id,
            time(),
        ], [
            ParameterType::STRING,
            ParameterType::INTEGER,
        ]);

        return (bool) $result->fetchOne();
    }

    /**
     * {@inheritdoc}
     */
    protected function doClear(string $namespace): bool
    {
        if ('' === $namespace) {
            if ('sqlite' === $this->getPlatformName()) {
                $sql = "DELETE FROM $this->table";
            } else {
                $sql = "TRUNCATE TABLE $this->table";
            }
        } else {
            $sql = "DELETE FROM $this->table WHERE $this->idCol LIKE '$namespace%'";
        }

        try {
            $this->conn->executeStatement($sql);
        } catch (TableNotFoundException $e) {
        }

        return true;
    }

    /**
     * {@inheritdoc}
     */
    protected function doDelete(array $ids): bool
    {
        $sql = "DELETE FROM $this->table WHERE $this->idCol IN (?)";
        try {
            $this->conn->executeStatement($sql, [array_values($ids)], [Connection::PARAM_STR_ARRAY]);
        } catch (TableNotFoundException $e) {
        }

        return true;
    }

    /**
     * {@inheritdoc}
     */
    protected function doSave(array $values, int $lifetime)
    {
        if (!$values = $this->marshaller->marshall($values, $failed)) {
            return $failed;
        }

        $platformName = $this->getPlatformName();
        $insertSql = "INSERT INTO $this->table ($this->idCol, $this->dataCol, $this->lifetimeCol, $this->timeCol) VALUES (?, ?, ?, ?)";

        switch (true) {
            case 'mysql' === $platformName:
                $sql = $insertSql." ON DUPLICATE KEY UPDATE $this->dataCol = VALUES($this->dataCol), $this->lifetimeCol = VALUES($this->lifetimeCol), $this->timeCol = VALUES($this->timeCol)";
                break;
            case 'oci' === $platformName:
                // DUAL is Oracle specific dummy table
                $sql = "MERGE INTO $this->table USING DUAL ON ($this->idCol = ?) ".
                    "WHEN NOT MATCHED THEN INSERT ($this->idCol, $this->dataCol, $this->lifetimeCol, $this->timeCol) VALUES (?, ?, ?, ?) ".
                    "WHEN MATCHED THEN UPDATE SET $this->dataCol = ?, $this->lifetimeCol = ?, $this->timeCol = ?";
                break;
            case 'sqlsrv' === $platformName && version_compare($this->getServerVersion(), '10', '>='):
                // MERGE is only available since SQL Server 2008 and must be terminated by semicolon
                // It also requires HOLDLOCK according to http://weblogs.sqlteam.com/dang/archive/2009/01/31/UPSERT-Race-Condition-With-MERGE.aspx
                $sql = "MERGE INTO $this->table WITH (HOLDLOCK) USING (SELECT 1 AS dummy) AS src ON ($this->idCol = ?) ".
                    "WHEN NOT MATCHED THEN INSERT ($this->idCol, $this->dataCol, $this->lifetimeCol, $this->timeCol) VALUES (?, ?, ?, ?) ".
                    "WHEN MATCHED THEN UPDATE SET $this->dataCol = ?, $this->lifetimeCol = ?, $this->timeCol = ?;";
                break;
            case 'sqlite' === $platformName:
                $sql = 'INSERT OR REPLACE'.substr($insertSql, 6);
                break;
            case 'pgsql' === $platformName && version_compare($this->getServerVersion(), '9.5', '>='):
                $sql = $insertSql." ON CONFLICT ($this->idCol) DO UPDATE SET ($this->dataCol, $this->lifetimeCol, $this->timeCol) = (EXCLUDED.$this->dataCol, EXCLUDED.$this->lifetimeCol, EXCLUDED.$this->timeCol)";
                break;
            default:
                $platformName = null;
                $sql = "UPDATE $this->table SET $this->dataCol = ?, $this->lifetimeCol = ?, $this->timeCol = ? WHERE $this->idCol = ?";
                break;
        }

        $now = time();
        $lifetime = $lifetime ?: null;
        try {
            $stmt = $this->conn->prepare($sql);
        } catch (TableNotFoundException $e) {
            if (!$this->conn->isTransactionActive() || \in_array($platformName, ['pgsql', 'sqlite', 'sqlsrv'], true)) {
                $this->createTable();
            }
            $stmt = $this->conn->prepare($sql);
        }

        // $id and $data are defined later in the loop. Binding is done by reference, values are read on execution.
        if ('sqlsrv' === $platformName || 'oci' === $platformName) {
            $stmt->bindParam(1, $id);
            $stmt->bindParam(2, $id);
            $stmt->bindParam(3, $data, ParameterType::LARGE_OBJECT);
            $stmt->bindValue(4, $lifetime, ParameterType::INTEGER);
            $stmt->bindValue(5, $now, ParameterType::INTEGER);
            $stmt->bindParam(6, $data, ParameterType::LARGE_OBJECT);
            $stmt->bindValue(7, $lifetime, ParameterType::INTEGER);
            $stmt->bindValue(8, $now, ParameterType::INTEGER);
        } elseif (null !== $platformName) {
            $stmt->bindParam(1, $id);
            $stmt->bindParam(2, $data, ParameterType::LARGE_OBJECT);
            $stmt->bindValue(3, $lifetime, ParameterType::INTEGER);
            $stmt->bindValue(4, $now, ParameterType::INTEGER);
        } else {
            $stmt->bindParam(1, $data, ParameterType::LARGE_OBJECT);
            $stmt->bindValue(2, $lifetime, ParameterType::INTEGER);
            $stmt->bindValue(3, $now, ParameterType::INTEGER);
            $stmt->bindParam(4, $id);

            $insertStmt = $this->conn->prepare($insertSql);
            $insertStmt->bindParam(1, $id);
            $insertStmt->bindParam(2, $data, ParameterType::LARGE_OBJECT);
            $insertStmt->bindValue(3, $lifetime, ParameterType::INTEGER);
            $insertStmt->bindValue(4, $now, ParameterType::INTEGER);
        }

        foreach ($values as $id => $data) {
            try {
                $rowCount = $stmt->executeStatement();
            } catch (TableNotFoundException $e) {
                if (!$this->conn->isTransactionActive() || \in_array($platformName, ['pgsql', 'sqlite', 'sqlsrv'], true)) {
                    $this->createTable();
                }
                $rowCount = $stmt->executeStatement();
            }
            if (null === $platformName && 0 === $rowCount) {
                try {
                    $insertStmt->executeStatement();
                } catch (DBALException $e) {
                    // A concurrent write won, let it be
                }
            }
        }

        return $failed;
    }

    private function getPlatformName(): string
    {
        if (isset($this->platformName)) {
            return $this->platformName;
        }

        $platform = $this->conn->getDatabasePlatform();

        switch (true) {
            case $platform instanceof \Doctrine\DBAL\Platforms\MySQLPlatform:
            case $platform instanceof \Doctrine\DBAL\Platforms\MySQL57Platform:
                return $this->platformName = 'mysql';

            case $platform instanceof \Doctrine\DBAL\Platforms\SqlitePlatform:
                return $this->platformName = 'sqlite';

            case $platform instanceof \Doctrine\DBAL\Platforms\PostgreSQLPlatform:
            case $platform instanceof \Doctrine\DBAL\Platforms\PostgreSQL94Platform:
                return $this->platformName = 'pgsql';

            case $platform instanceof \Doctrine\DBAL\Platforms\OraclePlatform:
                return $this->platformName = 'oci';

            case $platform instanceof \Doctrine\DBAL\Platforms\SQLServerPlatform:
            case $platform instanceof \Doctrine\DBAL\Platforms\SQLServer2012Platform:
                return $this->platformName = 'sqlsrv';

            default:
                return $this->platformName = \get_class($platform);
        }
    }

    private function getServerVersion(): string
    {
        if (isset($this->serverVersion)) {
            return $this->serverVersion;
        }

        $conn = $this->conn->getWrappedConnection();
        if ($conn instanceof ServerInfoAwareConnection) {
            return $this->serverVersion = $conn->getServerVersion();
        }

        return $this->serverVersion = '0';
    }

    private function addTableToSchema(Schema $schema): void
    {
        $types = [
            'mysql' => 'binary',
            'sqlite' => 'text',
        ];

        $table = $schema->createTable($this->table);
        $table->addColumn($this->idCol, $types[$this->getPlatformName()] ?? 'string', ['length' => 255]);
        $table->addColumn($this->dataCol, 'blob', ['length' => 16777215]);
        $table->addColumn($this->lifetimeCol, 'integer', ['unsigned' => true, 'notnull' => false]);
        $table->addColumn($this->timeCol, 'integer', ['unsigned' => true]);
        $table->setPrimaryKey([$this->idCol]);
    }
}
