<?php
/* vim: set expandtab sw=4 ts=4 sts=4: */
/**
 * file upload functions
 *
 * @package PhpMyAdmin
 */
if (! defined('PHPMYADMIN')) {
    exit;
}

/**
 * File wrapper class
 *
 * @todo when uploading a file into a blob field, should we also consider using
 *       chunks like in import? UPDATE `table` SET `field` = `field` + [chunk]
 *
 * @package PhpMyAdmin
 */
class PMA_File
{
    /**
     * @var string the temporary file name
     * @access protected
     */
    var $_name = null;

    /**
     * @var string the content
     * @access protected
     */
    var $_content = null;

    /**
     * @var string the error message
     * @access protected
     */
    var $_error_message = '';

    /**
     * @var bool whether the file is temporary or not
     * @access protected
     */
    var $_is_temp = false;

    /**
     * @var string type of compression
     * @access protected
     */
    var $_compression = null;

    /**
     * @var integer
     */
    var $_offset = 0;

    /**
     * @var integer size of chunk to read with every step
     */
    var $_chunk_size = 32768;

    /**
     * @var resource file handle
     */
    var $_handle = null;

    /**
     * @var boolean whether to decompress content before returning
     */
    var $_decompress = false;

    /**
     * @var string charset of file
     */
    var $_charset = null;

    /**
     * constructor
     *
     * @param string $name file name
     *
     * @access public
     */
    public function __construct($name = false)
    {
        if ($name) {
            $this->setName($name);
        }
    }

    /**
     * destructor
     *
     * @see     PMA_File::cleanUp()
     * @access  public
     */
    public function __destruct()
    {
        $this->cleanUp();
    }

    /**
     * deletes file if it is temporary, usally from a moved upload file
     *
     * @access  public
     * @return boolean success
     */
    public function cleanUp()
    {
        if ($this->isTemp()) {
            return $this->delete();
        }

        return true;
    }

    /**
     * deletes the file
     *
     * @access  public
     * @return boolean success
     */
    public function delete()
    {
        return unlink($this->getName());
    }

    /**
     * checks or sets the temp flag for this file
     * file objects with temp flags are deleted with object destruction
     *
     * @param boolean $is_temp sets the temp flag
     *
     * @return boolean PMA_File::$_is_temp
     * @access  public
     */
    public function isTemp($is_temp = null)
    {
        if (null !== $is_temp) {
            $this->_is_temp = (bool) $is_temp;
        }

        return $this->_is_temp;
    }

    /**
     * accessor
     *
     * @param string $name file name
     *
     * @return void
     * @access  public
     */
    public function setName($name)
    {
        $this->_name = trim($name);
    }

    /**
     * Gets file content
     *
     * @param boolean $as_binary whether to return content as binary
     * @param integer $offset    starting offset
     * @param integer $length    length
     *
     * @return mixed   the binary file content as a string,
     *                 or false if no content
     *
     * @access  public
     */
    public function getContent($as_binary = true, $offset = 0, $length = null)
    {
        if (null === $this->_content) {
            if ($this->isUploaded() && ! $this->checkUploadedFile()) {
                return false;
            }

            if (! $this->isReadable()) {
                return false;
            }

            if (function_exists('file_get_contents')) {
                $this->_content = file_get_contents($this->getName());
            } elseif ($size = filesize($this->getName())) {
                $this->_content = fread(fopen($this->getName(), 'rb'), $size);
            }
        }

        if (! empty($this->_content) && $as_binary) {
            return '0x' . bin2hex($this->_content);
        }

        if (null !== $length) {
            return substr($this->_content, $offset, $length);
        } elseif ($offset > 0) {
            return substr($this->_content, $offset);
        }

        return $this->_content;
    }

    /**
     * Whether file is uploaded.
     *
     * @access  public
     *
     * @return bool
     */
    public function isUploaded()
    {
        return is_uploaded_file($this->getName());
    }

    /**
     * accessor
     *
     * @access  public
     * @return string  PMA_File::$_name
     */
    public function getName()
    {
        return $this->_name;
    }

    /**
     * Initializes object from uploaded file.
     *
     * @param string $name name of file uploaded
     *
     * @return boolean success
     * @access  public
     */
    public function setUploadedFile($name)
    {
        $this->setName($name);

        if (! $this->isUploaded()) {
            $this->setName(null);
            $this->_error_message = __('File was not an uploaded file.');
            return false;
        }

        return true;
    }

    /**
     * Loads uploaded file from table change request.
     *
     * @param string $key       the md5 hash of the column name
     * @param string $rownumber number of row to process
     *
     * @return boolean success
     * @access  public
     */
    public function setUploadedFromTblChangeRequest($key, $rownumber)
    {
        if (! isset($_FILES['fields_upload'])
            || empty($_FILES['fields_upload']['name']['multi_edit'][$rownumber][$key])
        ) {
            return false;
        }
        $file = PMA_File::fetchUploadedFromTblChangeRequestMultiple(
            $_FILES['fields_upload'],
            $rownumber,
            $key
        );

        // check for file upload errors
        switch ($file['error']) {
        // we do not use the PHP constants here cause not all constants
        // are defined in all versions of PHP - but the correct constants names
        // are given as comment
        case 0: //UPLOAD_ERR_OK:
            return $this->setUploadedFile($file['tmp_name']);
            break;
        case 4: //UPLOAD_ERR_NO_FILE:
            break;
        case 1: //UPLOAD_ERR_INI_SIZE:
            $this->_error_message = __('The uploaded file exceeds the upload_max_filesize directive in php.ini.');
            break;
        case 2: //UPLOAD_ERR_FORM_SIZE:
            $this->_error_message = __('The uploaded file exceeds the MAX_FILE_SIZE directive that was specified in the HTML form.');
            break;
        case 3: //UPLOAD_ERR_PARTIAL:
            $this->_error_message = __('The uploaded file was only partially uploaded.');
            break;
        case 6: //UPLOAD_ERR_NO_TMP_DIR:
            $this->_error_message = __('Missing a temporary folder.');
            break;
        case 7: //UPLOAD_ERR_CANT_WRITE:
            $this->_error_message = __('Failed to write file to disk.');
            break;
        case 8: //UPLOAD_ERR_EXTENSION:
            $this->_error_message = __('File upload stopped by extension.');
            break;
        default:
            $this->_error_message = __('Unknown error in file upload.');
        } // end switch

        return false;
    }

    /**
     * strips some dimension from the multi-dimensional array from $_FILES
     *
     * <code>
     * $file['name']['multi_edit'][$rownumber][$key] = [value]
     * $file['type']['multi_edit'][$rownumber][$key] = [value]
     * $file['size']['multi_edit'][$rownumber][$key] = [value]
     * $file['tmp_name']['multi_edit'][$rownumber][$key] = [value]
     * $file['error']['multi_edit'][$rownumber][$key] = [value]
     *
     * // becomes:
     *
     * $file['name'] = [value]
     * $file['type'] = [value]
     * $file['size'] = [value]
     * $file['tmp_name'] = [value]
     * $file['error'] = [value]
     * </code>
     *
     * @param array  $file      the array
     * @param string $rownumber number of row to process
     * @param string $key       key to process
     *
     * @return array
     * @access  public
     * @static
     */
    public function fetchUploadedFromTblChangeRequestMultiple(
        $file, $rownumber, $key
    ) {
        $new_file = array(
            'name' => $file['name']['multi_edit'][$rownumber][$key],
            'type' => $file['type']['multi_edit'][$rownumber][$key],
            'size' => $file['size']['multi_edit'][$rownumber][$key],
            'tmp_name' => $file['tmp_name']['multi_edit'][$rownumber][$key],
            'error' => $file['error']['multi_edit'][$rownumber][$key],
        );

        return $new_file;
    }

    /**
     * sets the name if the file to the one selected in the tbl_change form
     *
     * @param string $key       the md5 hash of the column name
     * @param string $rownumber number of row to process
     *
     * @return boolean success
     * @access  public
     */
    public function setSelectedFromTblChangeRequest($key, $rownumber = null)
    {
        if (! empty($_REQUEST['fields_uploadlocal']['multi_edit'][$rownumber][$key])
            && is_string($_REQUEST['fields_uploadlocal']['multi_edit'][$rownumber][$key])
        ) {
            // ... whether with multiple rows ...
            return $this->setLocalSelectedFile(
                $_REQUEST['fields_uploadlocal']['multi_edit'][$rownumber][$key]
            );
        } else {
            return false;
        }
    }

    /**
     * Returns possible error message.
     *
     * @access  public
     * @return string  error message
     */
    public function getError()
    {
        return $this->_error_message;
    }

    /**
     * Checks whether there was any error.
     *
     * @access  public
     * @return boolean whether an error occured or not
     */
    public function isError()
    {
        return ! empty($this->_error_message);
    }

    /**
     * checks the superglobals provided if the tbl_change form is submitted
     * and uses the submitted/selected file
     *
     * @param string $key       the md5 hash of the column name
     * @param string $rownumber number of row to process
     *
     * @return boolean success
     * @access  public
     */
    public function checkTblChangeForm($key, $rownumber)
    {
        if ($this->setUploadedFromTblChangeRequest($key, $rownumber)) {
            // well done ...
            $this->_error_message = '';
            return true;
        } elseif ($this->setSelectedFromTblChangeRequest($key, $rownumber)) {
            // well done ...
            $this->_error_message = '';
            return true;
        }
        // all failed, whether just no file uploaded/selected or an error

        return false;
    }

    /**
     * Sets named file to be read from UploadDir.
     *
     * @param string $name file name
     *
     * @return boolean success
     * @access  public
     */
    public function setLocalSelectedFile($name)
    {
        if (empty($GLOBALS['cfg']['UploadDir'])) {
            return false;
        }

        $this->setName(
            PMA_Util::userDir($GLOBALS['cfg']['UploadDir']) . PMA_securePath($name)
        );
        if (! $this->isReadable()) {
            $this->_error_message = __('File could not be read');
            $this->setName(null);
            return false;
        }

        return true;
    }

    /**
     * Checks whether file can be read.
     *
     * @access  public
     * @return boolean whether the file is readable or not
     */
    public function isReadable()
    {
        // suppress warnings from being displayed, but not from being logged
        // any file access outside of open_basedir will issue a warning
        ob_start();
        $is_readable = is_readable($this->getName());
        ob_end_clean();
        return $is_readable;
    }

    /**
     * If we are on a server with open_basedir, we must move the file
     * before opening it. The FAQ 1.11 explains how to create the "./tmp"
     * directory - if needed
     *
     * @todo move check of $cfg['TempDir'] into PMA_Config?
     * @access  public
     * @return boolean whether uploaded fiel is fine or not
     */
    public function checkUploadedFile()
    {
        if ($this->isReadable()) {
            return true;
        }

        if (empty($GLOBALS['cfg']['TempDir'])
            || ! is_writable($GLOBALS['cfg']['TempDir'])
        ) {
            // cannot create directory or access, point user to FAQ 1.11
            $this->_error_message = __('Error moving the uploaded file, see [doc@faq1-11]FAQ 1.11[/doc]');
            return false;
        }

        $new_file_to_upload = tempnam(
            realpath($GLOBALS['cfg']['TempDir']),
            basename($this->getName())
        );

        // suppress warnings from being displayed, but not from being logged
        // any file access outside of open_basedir will issue a warning
        ob_start();
        $move_uploaded_file_result = move_uploaded_file(
            $this->getName(),
            $new_file_to_upload
        );
        ob_end_clean();
        if (! $move_uploaded_file_result) {
            $this->_error_message = __('Error while moving uploaded file.');
            return false;
        }

        $this->setName($new_file_to_upload);
        $this->isTemp(true);

        if (! $this->isReadable()) {
            $this->_error_message = __('Cannot read (moved) upload file.');
            return false;
        }

        return true;
    }

    /**
     * Detects what compression filse uses
     *
     * @todo    move file read part into readChunk() or getChunk()
     * @todo    add support for compression plugins
     * @access  protected
     * @return string MIME type of compression, none for none
     */
    protected function detectCompression()
    {
        // suppress warnings from being displayed, but not from being logged
        // f.e. any file access outside of open_basedir will issue a warning
        ob_start();
        $file = fopen($this->getName(), 'rb');
        ob_end_clean();

        if (! $file) {
            $this->_error_message = __('File could not be read');
            return false;
        }

        /**
         * @todo
         * get registered plugins for file compression

        foreach (PMA_getPlugins($type = 'compression') as $plugin) {
            if ($plugin['classname']::canHandle($this->getName())) {
                $this->setCompressionPlugin($plugin);
                break;
            }
        }
         */

        $test = fread($file, 4);
        $len = strlen($test);
        fclose($file);

        if ($len >= 2 && $test[0] == chr(31) && $test[1] == chr(139)) {
            $this->_compression = 'application/gzip';
        } elseif ($len >= 3 && substr($test, 0, 3) == 'BZh') {
            $this->_compression = 'application/bzip2';
        } elseif ($len >= 4 && $test == "PK\003\004") {
            $this->_compression = 'application/zip';
        } else {
            $this->_compression = 'none';
        }

        return $this->_compression;
    }

    /**
     * Sets whether the content should be decompressed before returned
     *
     * @param boolean $decompress whether to decompres
     *
     * @return void
     */
    public function setDecompressContent($decompress)
    {
        $this->_decompress = (bool) $decompress;
    }

    /**
     * Returns the file handle
     *
     * @return object file handle
     */
    public function getHandle()
    {
        if (null === $this->_handle) {
            $this->open();
        }
        return $this->_handle;
    }

    /**
     * Sets the file handle
     *
     * @param object $handle file handle
     *
     * @return void
     */
    public function setHandle($handle)
    {
        $this->_handle = $handle;
    }


    /**
     * Sets error message for unsupported compression.
     *
     * @return void
     */
    public function errorUnsupported()
    {
        $this->_error_message = sprintf(
            __('You attempted to load file with unsupported compression (%s). Either support for it is not implemented or disabled by your configuration.'),
            $this->getCompression()
        );
    }

    /**
     * Attempts to open the file.
     *
     * @return bool
     */
    public function open()
    {
        if (! $this->_decompress) {
            $this->_handle = @fopen($this->getName(), 'r');
        }

        switch ($this->getCompression()) {
        case false:
            return false;
        case 'application/bzip2':
            if ($GLOBALS['cfg']['BZipDump'] && @function_exists('bzopen')) {
                $this->_handle = @bzopen($this->getName(), 'r');
            } else {
                $this->errorUnsupported();
                return false;
            }
            break;
        case 'application/gzip':
            if ($GLOBALS['cfg']['GZipDump'] && @function_exists('gzopen')) {
                $this->_handle = @gzopen($this->getName(), 'r');
            } else {
                $this->errorUnsupported();
                return false;
            }
            break;
        case 'application/zip':
            if ($GLOBALS['cfg']['ZipDump'] && @function_exists('zip_open')) {
                include_once './libraries/zip_extension.lib.php';
                $result = PMA_getZipContents($this->getName());
                if (! empty($result['error'])) {
                    $this->_error_message = PMA_Message::rawError($result['error']);
                    return false;
                } else {
                    $this->content_uncompressed = $result['data'];
                }
                unset($result);
            } else {
                $this->errorUnsupported();
                return false;
            }
            break;
        case 'none':
            $this->_handle = @fopen($this->getName(), 'r');
            break;
        default:
            $this->errorUnsupported();
            return false;
            break;
        }

        return true;
    }

    /**
     * Returns the character set of the file
     *
     * @return string character set of the file
     */
    public function getCharset()
    {
        return $this->_charset;
    }

    /**
     * Sets the character set of the file
     *
     * @param string $charset character set of the file
     *
     * @return void
     */
    public function setCharset($charset)
    {
        $this->_charset = $charset;
    }

    /**
     * Returns compression used by file.
     *
     * @return string MIME type of compression, none for none
     * @access  public
     */
    public function getCompression()
    {
        if (null === $this->_compression) {
            return $this->detectCompression();
        }

        return $this->_compression;
    }

    /**
     * advances the file pointer in the file handle by $length bytes/chars
     *
     * @param integer $length numbers of chars/bytes to skip
     *
     * @return boolean
     * @todo this function is unused
     */
    public function advanceFilePointer($length)
    {
        while ($length > 0) {
            $this->getNextChunk($length);
            $length -= $this->getChunkSize();
        }
    }

    /**
     * http://bugs.php.net/bug.php?id=29532
     * bzip reads a maximum of 8192 bytes on windows systems
     *
     * @param int $max_size maximum size of the next chunk to be returned
     *
     * @return bool|string
     * @todo this function is unused
     */
    public function getNextChunk($max_size = null)
    {
        if (null !== $max_size) {
            $size = min($max_size, $this->getChunkSize());
        } else {
            $size = $this->getChunkSize();
        }

        // $result = $this->handler->getNextChunk($size);
        $result = '';
        switch ($this->getCompression()) {
        case 'application/bzip2':
            $result = '';
            while (strlen($result) < $size - 8192 && ! feof($this->getHandle())) {
                $result .= bzread($this->getHandle(), $size);
            }
            break;
        case 'application/gzip':
            $result = gzread($this->getHandle(), $size);
            break;
        case 'application/zip':
            /*
             * if getNextChunk() is used some day,
             * replace this code by code similar to the one
             * in open()
             *
            include_once './libraries/unzip.lib.php';
            $import_handle = new SimpleUnzip();
            $import_handle->ReadFile($this->getName());
            if ($import_handle->Count() == 0) {
                $this->_error_message = __('No files found inside ZIP archive!');
                return false;
            } elseif ($import_handle->GetError(0) != 0) {
                $this->_error_message = __('Error in ZIP archive:')
                    . ' ' . $import_handle->GetErrorMsg(0);
                return false;
            } else {
                $result = $import_handle->GetData(0);
            }
             */
            break;
        case 'none':
            $result = fread($this->getHandle(), $size);
            break;
        default:
            return false;
        }

        if ($GLOBALS['charset_conversion']) {
            $result = PMA_convertString($this->getCharset(), 'utf-8', $result);
        } else {
            /**
             * Skip possible byte order marks (I do not think we need more
             * charsets, but feel free to add more, you can use wikipedia for
             * reference: <http://en.wikipedia.org/wiki/Byte_Order_Mark>)
             *
             * @todo BOM could be used for charset autodetection
             */
            if ($this->getOffset() === 0) {
                // UTF-8
                if (strncmp($result, "\xEF\xBB\xBF", 3) == 0) {
                    $result = substr($result, 3);
                    // UTF-16 BE, LE
                } elseif (strncmp($result, "\xFE\xFF", 2) == 0
                    || strncmp($result, "\xFF\xFE", 2) == 0
                ) {
                    $result = substr($result, 2);
                }
            }
        }

        $this->_offset += $size;
        if (0 === $result) {
            return true;
        }
        return $result;
    }

    /**
     * Returns the offset
     *
     * @return integer the offset
     */
    public function getOffset()
    {
        return $this->_offset;
    }

    /**
     * Returns the chunk size
     *
     * @return integer the chunk size
     */
    public function getChunkSize()
    {
        return $this->_chunk_size;
    }

    /**
     * Sets the chunk size
     *
     * @param integer $chunk_size the chunk size
     *
     * @return void
     */
    public function setChunkSize($chunk_size)
    {
        $this->_chunk_size = (int) $chunk_size;
    }

    /**
     * Returns the length of the content in the file
     *
     * @return integer the length of the file content
     */
    public function getContentLength()
    {
        return strlen($this->_content);
    }

    /**
     * Returns whether the end of the file has been reached
     *
     * @return boolean whether the end of the file has been reached
     */
    public function eof()
    {
        if ($this->getHandle()) {
            return feof($this->getHandle());
        } else {
            return ($this->getOffset() >= $this->getContentLength());
        }

    }
}
?>