<?php

/****************************************
 * Example of how to use this uploader class...
 * You can uncomment the following lines (minus the require) to use these as your defaults.
 *
 * // list of valid extensions, ex. array("jpeg", "xml", "bmp")
 * $allowedExtensions = array();
 * // max file size in bytes
 * $sizeLimit = 10 * 1024 * 1024;
 *
 * require('valums-file-uploader/server/php.php');
 * $uploader = new qqFileUploader($allowedExtensions, $sizeLimit);
 *
 * // Call handleUpload() with the name of the folder, relative to PHP's getcwd()
 * $result = $uploader->handleUpload('uploads/');
 *
 * // to pass data through iframe you will need to encode all html tags
 * echo htmlspecialchars(json_encode($result), ENT_NOQUOTES);
 *
 * /******************************************/

/**
 * Handle file uploads via XMLHttpRequest
 */
class qqUploadedFileXhr
{
    /**
     * Save the file to the specified path
     *
     * @return boolean TRUE on success
     */
    function save($path)
    {
        $input = fopen("php://input", "r");
        $temp = tmpfile();
        $realSize = stream_copy_to_stream($input, $temp);
        fclose($input);

        if ($realSize != $this->getSize()) {
            return false;
        }

        $target = fopen($path, "w");
        fseek($temp, 0, SEEK_SET);
        stream_copy_to_stream($temp, $target);
        fclose($target);

        return true;
    }

    function getName()
    {
        return $_GET['qqfile'];
    }

    function getSize()
    {
        if (isset($_SERVER["CONTENT_LENGTH"])) {
            return (int)$_SERVER["CONTENT_LENGTH"];
        } else {
            throw new Exception('Getting content length is not supported.');
        }
    }
}

/**
 * Handle file uploads via regular form post (uses the $_FILES array)
 */
class qqUploadedFileForm
{
    /**
     * Save the file to the specified path
     *
     * @return boolean TRUE on success
     */
    function save($path)
    {
        if (!move_uploaded_file($_FILES['qqfile']['tmp_name'], $path)) {
            return false;
        }

        return true;
    }

    function getName()
    {
        return $_FILES['qqfile']['name'];
    }

    function getSize()
    {
        return $_FILES['qqfile']['size'];
    }
}

class qqFileUploader
{
    protected $allowedExtensions = [];

    protected $file;

    protected $sizeLimit = 10485760;

    protected $uploadName;

    public function getUploadName()
    {
        if (isset($this->uploadName)) {
            return $this->uploadName;
        }
    }

    public function getName()
    {
        if ($this->file) {
            return $this->file->getName();
        }
    }

    /**
     * Returns array('success'=>true) or array('error'=>'error message')
     */
    function handleUpload($uploadDirectory, $replaceOldFile = false)
    {
        if (!is_writable($uploadDirectory)) {
            return ['error' => "Server error. Upload directory isn't writable."];
        }

        if (!$this->file) {
            return ['error' => 'No files were uploaded.'];
        }

        $size = $this->file->getSize();

        if ($size == 0) {
            return ['error' => 'File is empty'];
        }

        if ($size > $this->sizeLimit) {
            return ['error' => 'File is too large'];
        }

        $pathinfo = pathinfo($this->file->getName());
        $filename = $pathinfo['filename'];
        //$filename = md5(uniqid());
        $ext = @$pathinfo['extension'];        // hide notices if extension is empty

        if ($this->allowedExtensions && !in_array(strtolower($ext), $this->allowedExtensions)) {
            $these = implode(', ', $this->allowedExtensions);

            return ['error' => 'File has an invalid extension, it should be one of ' . $these . '.'];
        }

        $ext = ($ext == '') ? $ext : '.' . $ext;

        if (!$replaceOldFile) {
            /// don't overwrite previous files that were uploaded
            while (file_exists($uploadDirectory . $filename . $ext)) {
                $filename .= rand(10, 99);
            }
        }

        $this->uploadName = $filename . $ext;

        if ($this->file->save($uploadDirectory . $filename . $ext)) {
            return ['success' => true];
        } else {
            return [
                'error' => 'Could not save uploaded file.' . 'The upload was cancelled, or server error encountered'
            ];
        }

    }

    protected function toBytes($str)
    {
        $val = trim($str);
        $last = strtolower($str[strlen($str) - 1]);
        switch ($last) {
            case 'g':
                $val *= 1024;
            case 'm':
                $val *= 1024;
            case 'k':
                $val *= 1024;
        }

        return $val;
    }

    private function checkServerSettings()
    {
        $postSize = $this->toBytes(ini_get('post_max_size'));
        $uploadSize = $this->toBytes(ini_get('upload_max_filesize'));

        if ($postSize < $this->sizeLimit || $uploadSize < $this->sizeLimit) {
            $size = max(1, $this->sizeLimit / 1024 / 1024) . 'M';
            die("{'error':'increase post_max_size and upload_max_filesize to $size'}");
        }
    }

    function __construct(array $allowedExtensions = [], $sizeLimit = 10485760)
    {
        $allowedExtensions = array_map("strtolower", $allowedExtensions);

        $this->allowedExtensions = $allowedExtensions;
        $this->sizeLimit = $sizeLimit;

        $this->checkServerSettings();

        if (!empty($_FILES)) {
            $this->file = new qqUploadedFileForm();
        } else if (isset($_GET['qqfile'])) {
            $this->file = new qqUploadedFileXhr();
        } else {
            $this->file = false;
        }
    }
}