<?php
/**
 * Copyright (c) 2021. ComboStrap, Inc. and its affiliates. All Rights Reserved.
 *
 * This source code is licensed under the GPL license found in the
 * COPYING  file in the root directory of this source tree.
 *
 * @license  GPL 3 (https://www.gnu.org/licenses/gpl-3.0.en.html)
 * @author   ComboStrap <support@combostrap.com>
 *
 */

namespace ComboStrap;

require_once(__DIR__ . '/LogUtility.php');

use helper_plugin_sqlite;
use helper_plugin_sqlite_adapter_pdosqlite;

class Sqlite
{

    /** @var helper_plugin_sqlite $sqlite */
    protected static $sqlite;

    /**
     *
     * @return helper_plugin_sqlite $sqlite
     */
    public static function getSqlite()
    {
        /**
         * sqlite is stored in a static variable
         * because when we run the {@link cli_plugin_combo},
         * we will run in the error:
         * ``
         * failed to open stream: Too many open files
         * ``
         * There is by default a limit of 1024 open files
         * which means that if there is more than 1024 pages, you fail.
         *
         * In test, we are running in different context (ie different root
         * directory for DokuWiki and therefore different $conf
         * and therefore different metadir where sqlite is stored)
         * Because a sql file may be deleted, we may get:
         * ```
         * RuntimeException: HY000 8 attempt to write a readonly database:
         * ```
         * To avoid this error, we check that we are still in the same metadir
         * where the sqlite database is stored. If not, we create a new instance
         *
         */
        global $conf;
        $metaDir = $conf['metadir'];
        $init = true;
        if (self::$sqlite != null) {
            $adapter = self::$sqlite->getAdapter();
            /**
             * Adapter may be null
             * when the SQLite & PDO SQLite
             * are not installed
             * ie: SQLite & PDO SQLite support missing
             */
            if ($adapter != null) {
                $dbFile = $adapter->getDbFile();
                if (file_exists($dbFile)) {
                    if (strpos($dbFile, $metaDir) === 0) {
                        $init = false;
                    } else {
                        self::$sqlite->getAdapter()->closedb();
                        self::$sqlite = null;
                    }
                }
            }
        }
        if ($init) {

            /**
             * Init
             */
            self::$sqlite = plugin_load('helper', 'sqlite');
            if (self::$sqlite == null) {
                # TODO: Man we cannot get the message anymore ['SqliteMandatory'];
                $sqliteMandatoryMessage = "The Sqlite Plugin is mandatory. Some functionalities of the ComboStrap Plugin may not work.";
                LogUtility::log2FrontEnd($sqliteMandatoryMessage, LogUtility::LVL_MSG_ERROR);
                return null;
            }
            $adapter = self::$sqlite->getAdapter();
            if ($adapter == null) {
                self::sendMessageAsNotAvailable();
                return null;
            }

            $adapter->setUseNativeAlter(true);

            // The name of the database (on windows, it should be
            $dbname = strtolower(PluginUtility::PLUGIN_BASE_NAME);
            global $conf;

            $oldDbName = '404manager';
            $oldDbFile = $conf['metadir'] . "/{$oldDbName}.sqlite";
            $oldDbFileSqlite3 = $conf['metadir'] . "/{$oldDbName}.sqlite3";
            if (file_exists($oldDbFile) || file_exists($oldDbFileSqlite3)) {
                $dbname = $oldDbName;
            }

            $init = self::$sqlite->init($dbname, DOKU_PLUGIN . PluginUtility::PLUGIN_BASE_NAME . '/db/');
            if (!$init) {
                # TODO: Message 'SqliteUnableToInitialize'
                $message = "Unable to initialize Sqlite";
                LogUtility::msg($message, MSG_MANAGERS_ONLY);
            } else {
                // regexp implementation
                // https://stackoverflow.com/questions/5071601/how-do-i-use-regex-in-a-sqlite-query/18484596#18484596
                $adapter = self::$sqlite->getAdapter();
                $adapter->create_function('regexp',
                    function ($pattern, $data, $delimiter = '~', $modifiers = 'isuS') {
                        if (isset($pattern, $data) === true) {
                            return (preg_match(sprintf('%1$s%2$s%1$s%3$s', $delimiter, $pattern, $modifiers), $data) > 0);
                        }
                        return null;
                    },
                    4
                );
            }
        }
        return self::$sqlite;

    }

    /**
     * Print debug info to the console in order to resolve
     * RuntimeException: HY000 8 attempt to write a readonly database
     * https://phpunit.readthedocs.io/en/latest/writing-tests-for-phpunit.html#error-output
     * @param helper_plugin_sqlite $sqlite
     */
    public static function printDbInfoAtConsole(helper_plugin_sqlite $sqlite)
    {
        $dbFile = $sqlite->getAdapter()->getDbFile();
        fwrite(STDERR, "Stderr DbFile: " . $dbFile . "\n");
        if (file_exists($dbFile)) {
            fwrite(STDERR, "File does exists\n");
            fwrite(STDERR, "Permission " . substr(sprintf('%o', fileperms($dbFile)), -4) . "\n");
        } else {
            fwrite(STDERR, "File does not exist\n");
        }

        global $conf;
        $metadir = $conf['metadir'];
        fwrite(STDERR, "MetaDir: " . $metadir . "\n");
        $subdir = strpos($dbFile, $metadir) === 0;
        if ($subdir) {
            fwrite(STDERR, "Meta is a subdirectory of the db \n");
        } else {
            fwrite(STDERR, "Meta is a not subdirectory of the db \n");
        }

    }

    /**
     * Json support
     */
    public static function supportJson(): bool
    {

        $sqlite = self::getSqlite();
        if ($sqlite === null) {
            self::sendMessageAsNotAvailable();
            return false;
        }

        $res = $sqlite->query("PRAGMA compile_options");
        $isJsonEnabled = false;
        foreach ($sqlite->res2arr($res) as $row) {
            if ($row["compile_option"] === "ENABLE_JSON1") {
                $isJsonEnabled = true;
                break;
            }
        };
        $sqlite->res_close($res);
        return $isJsonEnabled;
    }

    /**
     * @param helper_plugin_sqlite $sqlite
     * @param string $executableSql
     * @param array $parameters
     * @return bool|\PDOStatement|\SQLiteResult
     */
    public static function queryWithParameters(helper_plugin_sqlite $sqlite, string $executableSql, array $parameters)
    {
        $args = [$executableSql];
        $args = array_merge($args, $parameters);
        return $sqlite->getAdapter()->query($args);
    }

    public static function sendMessageAsNotAvailable(): void
    {
        $sqliteMandatoryMessage = "The Sqlite Php Extension is mandatory. It seems that it's not available on this installation.";
        LogUtility::log2FrontEnd($sqliteMandatoryMessage, LogUtility::LVL_MSG_ERROR);
    }
}