<?php

class Qs_Debug extends Qs_Db_Obj
{
    protected static $_instance;
    protected $_tableAlias = 'Log';
    protected $_errorReporting = E_ALL;
    protected $_previousErrorReporting = E_ALL;
    /** @var Zend_Log */
    protected $_log;
    protected $_idSession;
    protected $_startId;
    protected $_count;
    protected $_writed = false;
    protected $_writeLog = true;
    protected $_options = array();
    protected $_logBacktrace = false;
    protected static $_errorTypes = array(
        E_ERROR             => array('priority' => Zend_Log::ERR, 'type' => 'Fatal error'),        // 1
        E_WARNING           => array('priority' => Zend_Log::WARN, 'type' => 'Warning'),           // 2
        E_PARSE             => array('priority' => Zend_Log::ERR, 'type' => 'Parse Error'),        // 4
        E_NOTICE            => array('priority' => Zend_Log::NOTICE, 'type' => 'Notice'),          // 8
        E_CORE_ERROR        => array('priority' => Zend_Log::ERR, 'type' => 'Core Error'),         // 16
        E_CORE_WARNING      => array('priority' => Zend_Log::WARN, 'type' => 'Core Warning'),      // 32
        E_COMPILE_ERROR     => array('priority' => Zend_Log::ERR, 'type' => 'Compile Error'),      // 64
        E_COMPILE_WARNING   => array('priority' => Zend_Log::WARN, 'type' => 'Compile Warning'),   // 128
        E_USER_ERROR        => array('priority' => Zend_Log::ERR, 'type' => 'User Error'),         // 256
        E_USER_WARNING      => array('priority' => Zend_Log::WARN, 'type' => 'User Warning'),      // 512
        E_USER_NOTICE       => array('priority' => Zend_Log::NOTICE, 'type' => 'User Notice'),     // 1024
        E_STRICT            => array('priority' => Zend_Log::NOTICE, 'type' => 'Strict'),          // 2048
        E_RECOVERABLE_ERROR => array('priority' => Zend_Log::ERR, 'type' => 'Recoverable Error'),  // 4096
        E_DEPRECATED        => array('priority' => Zend_Log::NOTICE, 'type' => 'Deprecated'),      // 8192
        E_USER_DEPRECATED   => array('priority' => Zend_Log::NOTICE, 'type' => 'User Deprecated'), // 16384
    );

    
    protected function _init()
    {
        $columnMapping = array(
            'priority'   => 'priorityName',
            'message'    => 'message',
            'backtrace'  => 'backtrace',
            'ip'         => 'ip',
            'idSession'  => 'idSession',
            'serverName' => 'serverName',
            'url'        => 'url',
            'added'      => 'timestamp'
        );

        $writer = new Zend_Log_Writer_Db(Qs_Db::getInstance(), Qs_Db::getTableName('Log'), $columnMapping);
        $this->_log = new Zend_Log($writer);
        set_exception_handler(array($this, 'exceptionHandler'));
        if ($this->_writeLog) {
            $select = $this->_db->select();
            $select->from($this->_getPair(), array('maxId' => 'MAX(id)', 'count' => 'COUNT(*)'));
            $data = $this->_db->fetchRow($select);
            if (!empty($data)) {
                $this->_startId = $data['maxId'];
                $this->_count = $data['count'];
            }
        }
        $this->_idSession = Zend_Session::getId();
        $this->_clearOldHistory();
        return $this;
    }
    
    public function getOption($name)
    {
        if (isset($this->_options[$name])) {
            return $this->_options[$name];
        }
        return null;
    }
    
    public function setLogBacktrace($flag)
    {
        $this->_logBacktrace = (bool) $flag;
    }
    
    public function setWriteLog($flag)
    {
        $this->_writeLog = (bool) $flag;
    }

    /**
     * @return Qs_Debug
     * @throws Qs_Exception
     */
    public static function getInstance()
    {
        if (null === Qs_Debug::$_instance) {
            if (!Zend_Registry::isRegistered('config')) {
                throw new Qs_Exception('Config is not registered in Zend_Registry');
            }
            Qs_Debug::$_instance = new Qs_Debug(Zend_Registry::get('config')->debug);
        }
        return Qs_Debug::$_instance;
    }
    
    public function setErrorReporting($errorReporting)
    {
        $this->_previousErrorReporting = $this->_errorReporting;
        $this->_errorReporting = $errorReporting;
        error_reporting($errorReporting);
        set_error_handler(array($this, 'errorHandler'), $this->_errorReporting);
    }
    
    public function getErrorReporting()
    {
        return $this->_errorReporting;
    }
    
    public function restoreErrorReporting()
    {
        $this->_errorReporting = $this->_previousErrorReporting;
        set_error_handler(array($this, 'errorHandler'), $this->_errorReporting);
    }
    
    protected function _clearOldHistory()
    {
        if ($this->_writeLog) {
            if ($this->_count > $this->getOption('clearOverflow')) {
                $select = $this->_db->select();
                $select->from($this->_tableName, 'id')
                       ->order('id DESC')
                       ->limit(1, $this->getOption('clearLimit') - 1);
                if (false !== ($maxId = $this->_db->fetchOne($select))) {
                    $this->_db->delete($this->_tableName, 'id < ' . $this->_db->quote($maxId, Qs_Db::INT_TYPE));
                }
            }
        }
    }
    
    public function errorHandler($errNo, $errMsg, $filename, $linenNum, $errContext)
    {
        $debugMessage = '[' . $errNo . '] ' . $errMsg . '<br />';
        if (null !== $filename && null !== $linenNum) {
            $debugMessage .= 'In line ' . $linenNum . ' of ' . $filename . ".\n";
        }

        if (isset(self::$_errorTypes[$errNo])) {
            $info = self::$_errorTypes[$errNo];
            $priority = $info['priority'];
            $debugMessage = "<b>{$info['type']}:</b> {$debugMessage}";
        } else {
            $priority = Zend_Log::DEBUG;
            $debugMessage = "<b>Unknown Error ({$errNo}):</b> {$debugMessage}";
        }

        // Ignore warnings and notices from lib/Zend
        if (in_array($errNo, array(E_WARNING, E_NOTICE)) && false !== strpos($filename, BASE_PATH . '/lib/Zend')) {
            return true;
        }

        $this->_writeLog($debugMessage, $priority);
        return true;
    }
    
    public static function log($message, $priority = E_WARNING)
    {
        Qs_Debug::getInstance()->errorHandler($priority, $message, null, null, null);
    }
    
    public function writeLog($message, $priority)
    {
        return $this->_writeLog($message, $priority);
    }
    
    protected function _writeLog($message, $priority)
    {
        if (!$this->_writeLog) {
            return false;
        }
        $this->_log->setEventItem('serverName', $_SERVER['SERVER_NAME']);
        $this->_log->setEventItem('ip', $_SERVER['REMOTE_ADDR']);
        $this->_log->setEventItem('idSession', $this->_idSession);
        $this->_log->setEventItem('url', (string)Qs_Request::getUrl());
        if ($this->_logBacktrace) {
            $this->_log->setEventItem('backtrace', gzcompress(serialize(Qs_Debug::_getBackTrace()), 9));
        } else {
            $this->_log->setEventItem('backtrace', null);
        }
        $this->_log->log($message, $priority);
        $this->_writed = true;
        return true;
    }

    /**
     * Remove objects instances from array
     * (раніше приймав занчення по посиланню, в РНР 5.4 вилізла проблема, debug_backtrace повертає масив з посиланнями
     * на об'єкти, тому зміни в $array моломи сайт)
     * @param array $array
     * @return array
     */
    protected static function _removeObjects(array $array)
    {
        $result = array();
        foreach ($array as $key => $value) {
            if (is_array($value)) {
                $result[$key] = Qs_Debug::_removeObjects($value);
            } else if (is_object($value)) {
                $result[$key] = get_class($value) . ' Object';
            } else {
                $result[$key] = $value;
            }
        }
        return $result;
    }
    
    protected static function _getBackTrace()
    {
        $backtrace = debug_backtrace();
        array_shift($backtrace);
        array_shift($backtrace);
        array_shift($backtrace);
        $backtrace = Qs_Debug::_removeObjects($backtrace);
        return $backtrace;
    }
   
    public function getDebugInformation()
    {
        if (!$this->_writeLog || !$this->_writed) {
            return array();
        }
        $select = $this->_db->select();
        $select->from($this->_getPair(), array('added', 'priority', 'message'));
        $select->where("`{$this->_tableAlias}`.`id` > " . $this->_db->quote($this->_startId, Qs_Db::INT_TYPE));
        $select->where("`{$this->_tableAlias}`.`idSession` = " . $this->_db->quote($this->_idSession));
        $select->order($this->_tableAlias . '.id');
        $list = $this->_db->fetchAll($select);
        return $list;
    }
    
    public static function getExceptionMessage(Exception $exception)
    {
        $firstTracePoint = current($exception->getTrace());
        $html = '<br />'
              . '<b>' . $firstTracePoint['class'] . $firstTracePoint['type'] . $firstTracePoint['function'] . '</b>'
              . ' uncaught exception '
              . 'in ' . $exception->getFile() . ' on line <b>' . $exception->getLine() . ''
              . '<br/>'
              . '<span style="color:#DD0000"><b>' . nl2br(strip_tags($exception->getMessage())) . '</b></span>'
              . '<br />';
        if ($exception instanceof Zend_Db_Statement_Exception
            && false !== ($lastQueryProfile = Qs_Db::getInstance()->getProfiler()->getLastQueryProfile())
        ) {
            $html .= '<br/>Last query:<hr/><pre>'
                    . formatSql($lastQueryProfile->getQuery())
                    . '</pre>';
        }
        return $html;
    }

    /**
     * @param Exception $exception
     * @return string
     */
    public static function getExceptionBacktrace($exception)
    {
        $debugBacktrace = $exception->getTrace();
        $debugBacktrace = Qs_Debug::_removeObjects($debugBacktrace);
        return '<b>BACKTRACE</b><br /><pre>' . print_r($debugBacktrace, true) . '</pre>';
    }
    
    protected function _sendExceptionNotification($exception)
    {
        $message   = Qs_Debug::getExceptionMessage($exception);
        $backtrace = Qs_Debug::getExceptionBacktrace($exception);
        $html = $message
              . '<hr />'
              . '<b>URL</b>: <a href="' . Qs_Request::getUrl() . '">' . Qs_Request::getUrl() . '</a>';
        foreach (array('_GET', '_POST', '_COOKIE', '_SERVER', '_ENV') as $name) {
          $html .= '<hr /><b>$' . $name . '</b><br /><pre>' . htmlspecialchars(print_r($GLOBALS[$name], true)) . '</pre>';
        }
        $html .= '<hr />' . $backtrace;
        $notifyEmails = $this->getOption('notifyEmails');
        if (is_array($notifyEmails) && !empty($notifyEmails)) {
            $headers = 'From: debug@' . $_SERVER['SERVER_NAME'] . "\n"
                     . 'Reply-To: no-reply@' . $_SERVER['SERVER_NAME'] . "\n"
                     . 'Content-Type: text/html' . "\n"
                     . 'X-Mailer: PHP/' . phpversion();
            foreach ($notifyEmails as $email) {
                mail($email, 'Error Dump from ' . $_SERVER['SERVER_NAME'], $html, $headers);
            }
        }
        return $this;
    }

    /**
     * @param Exception $exception
     */
    public function exceptionHandler($exception)
    {
        $message   = Qs_Debug::getExceptionMessage($exception);
        $backtrace = Qs_Debug::getExceptionBacktrace($exception);
        $this->_writeLog($exception->getMessage(), 0);
        if (Qs_Constant::get('DEBUG')) {
            die($message . '<hr/>'. $backtrace);
        } 
        $this->_sendExceptionNotification($exception);
        die('Internal error');
    }
    
    public static function processException($exception)
    {
        Qs_Debug::getInstance()->exceptionHandler($exception);
    }
}