<?php

use Illuminate\Support\Facades\DB;

/**
 * Class MultipleFilesBackup
 * create a backup of this workspace
 *
 * Exports the database and copies the files to an tar archive o several if the max filesize is reached.
 */
class MultipleFilesBackup
{
    private $dir_to_compress = "";
    private $filename = "backUpProcessMaker.tar";
    private $fileSize = "1000";
    // 1 GB by default.
    private $sizeDescriptor = "m";
    //megabytes
    private $tempDirectories = array();

    /* Constructor
     *  @filename contains the path and filename of the comppress file(s).
     *  @size     got the Max size of the compressed files, by default if the $size less to zero will mantains 1000 Mb as Max size.
     */
    public function __construct($filename, $size)
    {
        if (!empty($filename)) {
            $this->filename = $filename;
        }
        if (!empty($size) && (int)$size > 0) {
            $this->fileSize = $size;
        }
    }

    /* Gets workspace information enough to make its backup.
     *  @workspace contains the workspace to be add to the commpression process.
     */
    public function addToBackup($workspace)
    {
        //verifing if workspace exists.
        if (!$workspace->workspaceExists()) {
            echo "Workspace {$workspace->name} not found\n";
            return false;
        }
        //create destination path
        if (!file_exists(PATH_DATA . "upgrade/")) {
            mkdir(PATH_DATA . "upgrade/");
        }
        $tempDirectory = PATH_DATA . "upgrade/" . basename(tempnam(__FILE__, ''));
        mkdir($tempDirectory);
        $metadata = $workspace->getMetadata();
        CLI::logging("Creating temporary files on database...\n");
        $metadata["databases"] = $workspace->exportDatabase($tempDirectory);
        $metadata["directories"] = array("{$workspace->name}");
        $metadata["version"] = 1;
        $metaFilename = "$tempDirectory/{$workspace->name}.meta";
        if (!file_put_contents($metaFilename, str_replace(array(",", "{", "}"), array(",\n  ", "{\n  ", "\n}\n"), G::json_encode($metadata)))) {
            CLI::logging("Could not create backup metadata");
        }
        CLI::logging("Adding database to backup...\n");
        $this->addDirToBackup($tempDirectory);
        CLI::logging("Adding files to backup...\n");
        $this->addDirToBackup($workspace->path);
        $this->tempDirectories[] = $tempDirectory;
    }

    /* Add a directory containing Db files or info files to be commpressed
     *  @directory the name and path of the directory to be add to the commpression process.
     */
    private function addDirToBackup($directory)
    {
        if (!empty($directory)) {
            $this->dir_to_compress .= $directory . " ";
        }
    }

    // Commpress the DB and files into a single or several files with numerical series extentions

    public function letsBackup()
    {
        // creating command
        $CommpressCommand = "tar czv ";
        $CommpressCommand .= $this->dir_to_compress;
        $CommpressCommand .= "| split -b ";
        $CommpressCommand .= $this->fileSize;
        $CommpressCommand .= "m -d - ";
        $CommpressCommand .= $this->filename . ".";
        //executing command to create the files
        echo exec($CommpressCommand);
        //Remove leftovers dirs.
        foreach ($this->tempDirectories as $tempDirectory) {
            CLI::logging("Deleting: " . $tempDirectory . "\n");
            G::rm_dir($tempDirectory);
        }
    }

    /* Restore from file(s) commpressed by letsBackup function, into a temporary directory
     *  @ filename     got the name and path of the compressed file(s), if there are many files with file extention as a numerical series, the extention should be discriminated.
     *  @ srcWorkspace contains the workspace to be restored.
     *  @ dstWorkspace contains the workspace to be overwriting.
     *  @ overwrite    got the option true if the workspace will be overwrite.
     */
    public static function letsRestore($filename, $srcWorkspace, $dstWorkspace = null, $overwrite = true)
    {
        // Needed info:
        // TEMPDIR  /shared/workflow_data/upgrade/
        // BACKUPS  /shared/workflow_data/backups/
        // Creating command  cat myfiles_split.tgz_* | tar xz
        $DecommpressCommand = "cat " . $filename . ".* ";
        $DecommpressCommand .= " | tar xzv";

        $tempDirectory = PATH_DATA . "upgrade/" . basename(tempnam(__FILE__, ''));
        $tempDirectoryHelp = $tempDirectory;

        $parentDirectory = PATH_DATA . "upgrade";
        if (is_writable($parentDirectory)) {
            mkdir($tempDirectory);
        } else {
            throw new Exception("Could not create directory:" . $parentDirectory);
        }
        //Extract all backup files, including database scripts and workspace files
        CLI::logging("Restoring into " . $tempDirectory . "\n");
        chdir($tempDirectory);
        echo exec($DecommpressCommand);
        CLI::logging("\nUncompressed into: " . $tempDirectory . "\n");

        //Search for metafiles in the new standard (the old standard would contain meta files.
        $decommpressedfile = scandir($tempDirectoryHelp . dirname($tempDirectoryHelp), 1);
        $tempDirectory = $tempDirectoryHelp . dirname($tempDirectoryHelp) . "/" . $decommpressedfile[0];

        $metaFiles = glob($tempDirectory . "/*.meta");
        if (empty($metaFiles)) {
            $metaFiles = glob($tempDirectory . "/*.txt");
            if (!empty($metaFiles)) {
                return WorkspaceTools::restoreLegacy($tempDirectory);
            } else {
                throw new Exception("No metadata found in backup");
            }
        } else {
            CLI::logging("Found " . count($metaFiles) . " workspaces in backup:\n");
            foreach ($metaFiles as $metafile) {
                CLI::logging("-> " . basename($metafile) . "\n");
            }
        }
        if (count($metaFiles) > 1 && (!isset($srcWorkspace))) {
            throw new Exception("Multiple workspaces in backup but no workspace specified to restore");
        }
        if (isset($srcWorkspace) && !in_array("$srcWorkspace.meta", array_map(basename, $metaFiles))) {
            throw new Exception("Workspace $srcWorkspace not found in backup");
        }
        foreach ($metaFiles as $metaFile) {
            $metadata = G::json_decode(file_get_contents($metaFile));
            if ($metadata->version != 1) {
                throw new Exception("Backup version {$metadata->version} not supported");
            }
            $backupWorkspace = $metadata->WORKSPACE_NAME;
            if (isset($dstWorkspace)) {
                $workspaceName = $dstWorkspace;
                $createWorkspace = true;
            } else {
                $workspaceName = $metadata->WORKSPACE_NAME;
                $createWorkspace = false;
            }
            if (isset($srcWorkspace) && strcmp($metadata->WORKSPACE_NAME, $srcWorkspace) != 0) {
                CLI::logging(CLI::warning("> Workspace $backupWorkspace found, but not restoring.") . "\n");
                continue;
            } else {
                CLI::logging('> Restoring ' . CLI::info($backupWorkspace) . ' to ' . CLI::info($workspaceName) . "\n");
            }
            $workspace = new WorkspaceTools($workspaceName);
            if ($workspace->workspaceExists()) {
                if ($overwrite) {
                    CLI::logging(CLI::warning("> Workspace $workspaceName already exist, overwriting!") . "\n");
                } else {
                    throw new Exception('Destination workspace already exist (use -o to overwrite)');
                }
            }
            if (file_exists($workspace->path)) {
                G::rm_dir($workspace->path);
            }

            $tempDirectorySite = $tempDirectoryHelp . dirname($workspace->path);

            foreach ($metadata->directories as $dir) {
                CLI::logging("+> Restoring directory '$dir'\n");
                if (!rename("$tempDirectorySite/$dir", $workspace->path)) {
                    throw new Exception("There was an error copying the backup files ($tempDirectory/$dir) to the workspace directory {$workspace->path}.");
                }
            }

            CLI::logging("> Changing file permissions\n");
            $shared_stat = stat(PATH_DATA);
            if ($shared_stat !== false) {
                WorkspaceTools::dirPerms($workspace->path, $shared_stat['uid'], $shared_stat['gid'], $shared_stat['mode']);
            } else {
                CLI::logging(CLI::error("Could not get the shared folder permissions, not changing workspace permissions") . "\n");
            }

            list($dbHost, $dbUser, $dbPass) = @explode(SYSTEM_HASH, G::decrypt(HASH_INSTALLATION, SYSTEM_HASH));

            CLI::logging("> Connecting to system database in '$dbHost'\n");

            try {
                $connectionLestRestore = 'RESTORE';
                InstallerModule::setNewConnection($connectionLestRestore, $dbHost, $dbUser, $dbPass, '', '');
                DB::connection($connectionLestRestore)
                    ->statement("SET NAMES 'utf8'");
                DB::connection($connectionLestRestore)
                    ->statement('SET FOREIGN_KEY_CHECKS=0');
            } catch (Exception $exception) {
                throw new Exception('Could not connect to system database: ' . $exception->getMessage());
            }


            $onedb = false;
            if (strpos($metadata->DB_RBAC_NAME, 'rb_') === false) {
                $onedb = true;
            }

            $newDBNames = $workspace->resetDBInfo($dbHost, $createWorkspace, $onedb);
            $aParameters = ['dbHost' => $dbHost, 'dbUser' => $dbUser, 'dbPass' => $dbPass];

            foreach ($metadata->databases as $db) {
                $dbName = $newDBNames[$db->name];
                CLI::logging("+> Restoring database {$db->name} to $dbName\n");
                $workspace->executeSQLScript($dbName, "$tempDirectory/{$db->name}.sql", $aParameters, 1, $connectionLestRestore);
                $workspace->createDBUser($dbName, $db->pass, "localhost", $dbName, $connectionLestRestore);
                $workspace->createDBUser($dbName, $db->pass, "%", $dbName, $connectionLestRestore);
            }
            $workspace->upgradeCacheView(false);
        }
        CLI::logging("Removing temporary files\n");
        G::rm_dir($tempDirectory);
        CLI::logging(CLI::info("Done restoring") . "\n");
    }
}