<?php

define("DB_USER", 'root'); // 디비유저
define("DB_PASSWORD", ''); // 패스워드
define("DB_NAME", 'evening2'); // 디비명
define("DB_HOST", 'localhost'); // 디비호스트
define("BACKUP_DIR", '.'); // 백업저장용 폴더
define("TABLES", '*'); // 백업하려는 테이블명 (* 은 디비안의 모든 테이블을 백업)
//define("TABLES", 'table1, table2, table3'); // table1, table2, table3 만 백업
define("CHARSET", 'utf8');
define("GZIP_BACKUP_FILE", true);

/**
 * 디비백업 클래스
 */
class Backup_Database {
    var $host;
    var $username;
    var $passwd;
    var $dbName;
    var $charset;
    var $conn;
    var $backupDir;
    var $backupFile;
    var $gzipBackupFile;
    var $output;

    public function __construct($host, $username, $passwd, $dbName, $charset = 'utf8') {
        $this->host            = $host;
        $this->username        = $username;
        $this->passwd          = $passwd;
        $this->dbName          = $dbName;
        $this->charset         = $charset;
        $this->conn            = $this->initializeDatabase();
        $this->backupDir       = BACKUP_DIR ? BACKUP_DIR : '.';
        $this->backupFile      = 'myphp-backup-'.$this->dbName.'-'.date("Ymd_His", time()).'.sql';
        $this->gzipBackupFile  = defined('GZIP_BACKUP_FILE') ? GZIP_BACKUP_FILE : true;
        $this->output          = '';
    }

    protected function initializeDatabase() {
        try {
            $conn = mysqli_connect($this->host, $this->username, $this->passwd, $this->dbName);
            if (mysqli_connect_errno()) {
                throw new Exception('ERROR connecting database: ' . mysqli_connect_error());
                die();
            }
            if (!mysqli_set_charset($conn, $this->charset)) {
                mysqli_query($conn, 'SET NAMES '.$this->charset);
            }
        } catch (Exception $e) {
            print_r($e->getMessage());
            die();
        }

        return $conn;
    }
    
    public function backupTables($tables = '*') {
        try {
            /**
             * Tables to export
             */
            if($tables == '*') {
                $tables = array();
                $result = mysqli_query($this->conn, 'SHOW TABLES');
                while($row = mysqli_fetch_row($result)) {
                    $tables[] = $row[0];
                }
            } else {
                $tables = is_array($tables) ? $tables : explode(',', str_replace(' ', '', $tables));
            }

            $sql = 'CREATE DATABASE IF NOT EXISTS `'.$this->dbName."`;\n\n";
            $sql .= 'USE `'.$this->dbName."`;\n\n";

            /**
             * Iterate tables
             */
            foreach($tables as $table) {
                $this->obfPrint("Backing up `".$table."` table...".str_repeat('.', 50-strlen($table)), 0, 0);

                /**
                 * CREATE TABLE
                 */
                $sql .= 'DROP TABLE IF EXISTS `'.$table.'`;';
                $row = mysqli_fetch_row(mysqli_query($this->conn, 'SHOW CREATE TABLE `'.$table.'`'));
                $sql .= "\n\n".$row[1].";\n\n";

                /**
                 * INSERT INTO
                 */

                $row = mysqli_fetch_row(mysqli_query($this->conn, 'SELECT COUNT(*) FROM `'.$table.'`'));
                $numRows = $row[0];

                // Split table in batches in order to not exhaust system memory
                $batchSize = 1000; // Number of rows per batch
                $numBatches = intval($numRows / $batchSize) + 1; // Number of while-loop calls to perform
                for ($b = 1; $b <= $numBatches; $b++) {

                    $query = 'SELECT * FROM `'.$table.'` LIMIT '.($b*$batchSize-$batchSize).','.$batchSize;
                    $result = mysqli_query($this->conn, $query);
                    $numFields = mysqli_num_fields($result);

                    for ($i = 0; $i < $numFields; $i++) {
                        $rowCount = 0;
                        while($row = mysqli_fetch_row($result)) {
                            $sql .= 'INSERT INTO `'.$table.'` VALUES(';
                            for($j=0; $j<$numFields; $j++) {
                                if (isset($row[$j])) {
                                    $row[$j] = addslashes($row[$j]);
                                    $row[$j] = str_replace("\n","\\n",$row[$j]);
                                    $sql .= '"'.$row[$j].'"' ;
                                } else {
                                    $sql.= 'NULL';
                                }

                                if ($j < ($numFields-1)) {
                                    $sql .= ',';
                                }
                            }

                            $sql.= ");\n";
                        }
                    }

                    $this->saveFile($sql);
                    $sql = '';
                }

                $sql.="\n\n\n";

                $this->obfPrint(" OK");
            }

            if ($this->gzipBackupFile) {
                $this->gzipBackupFile();
            } else {
                $this->obfPrint('Backup file succesfully saved to ' . $this->backupDir.'/'.$this->backupFile, 1, 1);
            }
        } catch (Exception $e) {
            print_r($e->getMessage());
            return false;
        }

        return true;
    }

    protected function saveFile(&$sql) {
        if (!$sql) return false;

        try {

            if (!file_exists($this->backupDir)) {
                mkdir($this->backupDir, 0777, true);
            }

            file_put_contents($this->backupDir.'/'.$this->backupFile, $sql, FILE_APPEND | LOCK_EX);

        } catch (Exception $e) {
            print_r($e->getMessage());
            return false;
        }

        return true;
    }

    protected function gzipBackupFile($level = 9) {
        if (!$this->gzipBackupFile) {
            return true;
        }

        $source = $this->backupDir . '/' . $this->backupFile;
        $dest =  $source . '.gz';

        $this->obfPrint('Gzipping backup file to ' . $dest . '... ', 1, 0);

        $mode = 'wb' . $level;
        if ($fpOut = gzopen($dest, $mode)) {
            if ($fpIn = fopen($source,'rb')) {
                while (!feof($fpIn)) {
                    gzwrite($fpOut, fread($fpIn, 1024 * 256));
                }
                fclose($fpIn);
            } else {
                return false;
            }
            gzclose($fpOut);
            if(!unlink($source)) {
                return false;
            }
        } else {
            return false;
        }

        $this->obfPrint('OK');
        return $dest;
    }

    public function obfPrint ($msg = '', $lineBreaksBefore = 0, $lineBreaksAfter = 1) {
        if (!$msg) {
            return false;
        }

        $output = '';

        if (php_sapi_name() != "cli") {
            $lineBreak = "<br />";
        } else {
            $lineBreak = "\n";
        }

        if ($lineBreaksBefore > 0) {
            for ($i = 1; $i <= $lineBreaksBefore; $i++) {
                $output .= $lineBreak;
            }
        }

        $output .= $msg;

        if ($lineBreaksAfter > 0) {
            for ($i = 1; $i <= $lineBreaksAfter; $i++) {
                $output .= $lineBreak;
            }
        }


        // Save output for later use
        $this->output .= str_replace('<br />', '\n', $output);

        echo $output;


        if (php_sapi_name() != "cli") {
            ob_flush();
        }

        $this->output .= " ";

        flush();
    }

   
    public function getOutput() {
        return $this->output;
    }
}


error_reporting(E_ALL);
set_time_limit(900); // 15 minutes

if (php_sapi_name() != "cli") {
    echo '<div style="font-family: monospace;">';
}

$backupDatabase = new Backup_Database(DB_HOST, DB_USER, DB_PASSWORD, DB_NAME);
$result = $backupDatabase->backupTables(TABLES, BACKUP_DIR) ? 'OK' : 'KO';
$backupDatabase->obfPrint('Backup result: ' . $result, 1);

$output = $backupDatabase->getOutput();

if (php_sapi_name() != "cli") {
    echo '</div>';
}