<?php
/**
 * Created by PhpStorm.
 * User: crose
 * Date: 4/17/17
 * Time: 11:32 AM
 *
 * Check: CODING.md > Download
 */

namespace IMATHUZH\Qfq\Core\Report;

use IMATHUZH\Qfq\Core\Helper\KeyValueStringParser;
use IMATHUZH\Qfq\Core\Store\Session;
use IMATHUZH\Qfq\Core\Store\Store;
use IMATHUZH\Qfq\Core\Store\Sip;
use IMATHUZH\Qfq\Core\Helper\OnArray;
use IMATHUZH\Qfq\Core\Helper\OnString;
use IMATHUZH\Qfq\Core\Helper\Logger;
use IMATHUZH\Qfq\Core\Helper\Sanitize;
use IMATHUZH\Qfq\Core\Helper\HelperFile;
use IMATHUZH\Qfq\Core\Helper\DownloadPage;
use IMATHUZH\Qfq\Core\QuickFormQuery;

use IMATHUZH\Qfq\Core\Database\Database;
use IMATHUZH\Qfq\Core\Helper\Support;

/**
 * Class Download
 *
 * Documentation: PROTOCOL.md >> Download
 *
 * Param: i=1..n
 *   <i>_mode=direct | html2pdf
 *   <i>_id=<pageId>
 *   <i>_<key i>=<value i>
 *
 * @package qfq
 */
class Download {

    /**
     * @var Store
     */
    private $store = null;

    /**
     * @var Session
     */
    private $session = null;

    /**
     * @var Database
     */
    private $db = null;

    /**
     * @var Html2Pdf
     */
    private $html2pdf = null;

    /**
     * @var string Filename where to write download Information
     */
    private $downloadDebugLog = '';

    /**
     * @var string DOWNLOAD_OUTPUT_FORMAT_RAW | DOWNLOAD_OUTPUT_FORMAT_JSON
     */
    private $outputFormat = DOWNLOAD_OUTPUT_FORMAT_RAW;

    /**
     * @param bool|false $phpUnit
     * @throws \CodeException
     * @throws \DbException
     * @throws \UserFormException
     * @throws \UserReportException
     */
    public function __construct($phpUnit = false) {

        #TODO: rewrite $phpUnit to: "if (!defined('PHPUNIT_QFQ')) {...}"
        $this->session = Session::getInstance($phpUnit);
        $this->store = Store::getInstance('', $phpUnit);
        $this->db = new Database();
        $this->html2pdf = new Html2Pdf($this->store->getStore(STORE_SYSTEM), $phpUnit);

        if (Support::findInSet(SYSTEM_SHOW_DEBUG_INFO_DOWNLOAD, $this->store->getVar(SYSTEM_SHOW_DEBUG_INFO, STORE_SYSTEM))) {
            $this->downloadDebugLog = $this->store->getVar(SYSTEM_SQL_LOG, STORE_SYSTEM);
        }
    }

    /**
     * Concatenate all named files to one PDF file. Return name of new full PDF.
     *
     * @param array $files
     *
     * @return string  - fileName of concatenated file
     * @throws \CodeException
     * @throws \DownloadException
     * @throws \UserFormException
     */
    private function concatPdfFiles(array $files) {

        // Remove empty entries. Might happen if there was no upload
        $files = OnArray::removeEmptyElementsFromArray($files);

        // Check that all files exist and are readable
        foreach ($files AS $filename) {
            if (!is_readable($filename)) {
                throw new \DownloadException("Error reading file $filename. Not found or no permission", ERROR_DOWNLOAD_FILE_NOT_READABLE);
            }
        }

        if (count($files) === 0) {
            return '';
        }

        // Check that all files are of type 'application/pdf'
        foreach ($files AS $filename) {
            $mimetype = mime_content_type($filename);
            if ($mimetype != 'application/pdf') {
                throw new \DownloadException("Error concat file $filename. Mimetype 'application/pdf' expected, got: $mimetype", ERROR_DOWNLOAD_UNEXPECTED_MIME_TYPE);
            }
        }

        if (count($files) == 1) {
            return $files[0];
        }

        $files = OnArray::arrayEscapeshellarg($files);
        $inputFiles = implode(' ', $files);
        if (trim($inputFiles) == '') {
            throw new \DownloadException('No files to concatenate.', ERROR_DOWNLOAD_NO_FILES);
        }

        // Need to create a separate result file, even if it is just a single file (#6929)
        $concatFile = HelperFile::tempnam();
        if (false === $concatFile) {
            throw new \DownloadException('Error creating output file.', ERROR_DOWNLOAD_CREATE_NEW_FILE);
        }

//        $cmd = "pdftk $inputFiles cat output $concatFile 2>&1";  # Outdated. Hard to install on Ubuntu 18. Fails for recent PDFs.
//        $cmd = "qpdf --empty --pages $inputFiles -- $concatFile 2>&1"; # Fails to merge identical files, if they contain references.
        $cmd = "pdfunite $inputFiles $concatFile 2>&1"; // Based on poppler. URLs are preserved. Orientation and size are preserved.

        if ($this->downloadDebugLog != '') {
            Logger::logMessage("Download: $cmd", $this->downloadDebugLog);
        }

        exec($cmd, $output, $rc);

        if ($rc != 0) {
            throw new \DownloadException (json_encode([ERROR_MESSAGE_TO_USER => "Failed to merge PDF file",
                    ERROR_MESSAGE_TO_DEVELOPER => "CMD: " . $cmd . "<br>RC: $rc<br>Output: " . implode("<br>", $output)])
                , ERROR_DOWNLOAD_MERGE_FAILED);
        }

        return $concatFile;
    }

    /**
     * Get the mimetype of $filename and store them in $rcMimetype.
     * Checks if the extension of $outputFilename fit's to the mimetype. If not, append the mimetype extension.
     *
     * @param string $filename
     * @param string $outputFilename
     * @param string $rcMimetype
     *
     * @return string possible updated $outputFilename, according the mimetype.
     */
    private function targetFilenameExtension($filename, $outputFilename, &$rcMimetype) {

        $rcMimetype = mime_content_type($filename);

        return $outputFilename;
    }

    /**
     * Set header type and output $filename. Be careful not to send any additional characters.
     *
     * @param $file
     * @param $outputFilename
     * @throws \DownloadException
     */
    private function outputFile($file, $outputFilename) {

        $json = '';
        $flagJson = ($this->getOutputFormat() === DOWNLOAD_OUTPUT_FORMAT_JSON);

        $outputFilename = $this->targetFilenameExtension($file, $outputFilename, $mimeType);
        $outputFilename = Sanitize::safeFilename($outputFilename); // be sure that there are no problematic chars in the filename. E.g. MacOS X don't like spaces for downloads.

        if ($flagJson) {
            if (false === ($json = json_encode([JSON_TEXT => file_get_contents($file)]))) {
                throw new \DownloadException(json_encode(
                    [ERROR_MESSAGE_TO_USER => 'Error converting to JSON',
                        ERROR_MESSAGE_TO_DEVELOPER => "json_last_error()=" . json_last_error() . ", File=" . $file]), ERROR_DOWNLOAD_JSON_CONVERT);
            }
            $length = strlen($json);

            $mimeType = 'application/json';
        } else {
            $length = filesize($file);
        }

        header("Content-type: $mimeType");
        header("Content-Length: $length");
        if (!$flagJson) {
            // If defined as 'attachment': PDFs are not shown inside the browser (if user configured that). Instead, always a 'save as'-dialog appears (Chrome, FF)
            // header("Content-Disposition: attachment; filename=$outputFilename");
            header("Content-Disposition: inline; filename=\"$outputFilename\"; name=\"$outputFilename\"");
        }
        header("Pragma: no-cache");
        header("Expires: 0");

        if ($flagJson) {
            print $json;
        } else {
            readfile($file);
        }
    }

    /**
     * Interprets $element and fetches corresponding content, either as a file or the content in a variable.
     *
     * @param string $element - U:id=myExport&r=12, u:http://www.nzz.ch/issue?nr=21, f:fileadmin/sample.pdf
     *
     * @param string $downloadMode - DOWNLOAD_MODE_EXCEL | ....
     * @param string $rcData - With $downloadMode=DOWNLOAD_MODE_EXCEL, this contains the rendered code from the given T3 page.
     * @return string filename - already ready or fresh exported. Fresh exported needs to be deleted later.
     * @throws \CodeException
     * @throws \DbException
     * @throws \DownloadException
     * @throws \UserFormException
     * @throws \UserReportException
     * @throws \PhpOffice\PhpSpreadsheet\Exception
     * @throws \PhpOffice\PhpSpreadsheet\Reader\Exception
     * @throws \PhpOffice\PhpSpreadsheet\Writer\Exception
     */
    private function getElement($element, $downloadMode, &$rcData) {

        $filename = '';
        $rcArgs = array();
        $rcSipEncode = false;

        $arr = explode(':', $element, 2);
        if (count($arr) != 2) {
            $possibleReason = ($element === '') ? 'If this is a download link, did you forget to include s:1?' : '';
            throw new \DownloadException("Missing parameter for '$element'. $possibleReason", ERROR_MISSING_REQUIRED_PARAMETER);
        }

        $token = $arr[0];
        $value = $arr[1];
        if ($token === TOKEN_UID) { // extract uid
            $uidParamsArr = explode('&', $value, 2);
            $uid = $uidParamsArr[0];
            $value = $uidParamsArr[1] ?? ''; // additional params
        }

        switch ($token) {
            case TOKEN_URL:
            case TOKEN_URL_PARAM:
            case TOKEN_PAGE:
            case TOKEN_UID:
                $urlParam = OnString::splitParam($value, $rcArgs, $rcSipEncode);
                $urlParamString = KeyValueStringParser::unparse($urlParam, '=', '&');
                if ($rcSipEncode) {
                    $sip = new Sip();
                    $urlParamString = $sip->queryStringToSip($urlParamString, RETURN_URL);
                }

                if ($downloadMode == DOWNLOAD_MODE_EXCEL) {
                    if ($token === TOKEN_UID) {
                        $rcData = $this->getEvaluatedBodytext($uid, $urlParam);
                    } else {
                        $baseUrl = $this->store->getVar(SYSTEM_BASE_URL, STORE_SYSTEM);
                        $rcData = DownloadPage::getContent($urlParamString, $baseUrl);
                    }
                } else {
                    if ($token === TOKEN_UID) {
                        // create tmp html document with bodytext
                        $htmlText = $this->getEvaluatedBodytext($uid, $urlParam);
                        $tmpFilename = HelperFile::tempnam() . '.html';

                        $tmpFile = fopen($tmpFilename, "w") or die('Cannot create file:  ' . $tmpFilename);
                        fwrite($tmpFile, $htmlText);
                        fclose($tmpFile);

                        $rcArgsString = KeyValueStringParser::unparse($rcArgs, '=', '&');
                        $url = Support::mergeUrlComponents('', $tmpFilename, $rcArgsString);
                        $filename = $this->html2pdf->page2pdf($token, $url);
                        HelperFile::cleanTempFiles([$tmpFilename]);

                    } else {
                        $filename = $this->html2pdf->page2pdf($token, $value);
                    }
                }
                break;

            case TOKEN_FILE:
            case TOKEN_FILE_DEPRECATED:
                $filename = $value;
                break;
            default:
                throw new \DownloadException('Unknown token: "' . $token . '"', ERROR_UNKNOWN_TOKEN);
                break;
        }

        return $filename;
    }

    /**
     * @param $uid
     * @param array $urlParam
     *
     * @return string
     * @throws \CodeException
     * @throws \DbException
     * @throws \DownloadException
     * @throws \UserFormException
     * @throws \UserReportException
     * @throws \PhpOffice\PhpSpreadsheet\Exception
     * @throws \PhpOffice\PhpSpreadsheet\Reader\Exception
     * @throws \PhpOffice\PhpSpreadsheet\Writer\Exception
     */
    private function getEvaluatedBodyText($uid, $urlParam) {
        foreach ($urlParam as $key => $paramValue) {
            $this->store->setVar($key, $paramValue, STORE_SIP);
        }

        $dbT3 = $this->store->getVar(SYSTEM_DB_NAME_T3, STORE_SYSTEM);
        $sql = "SELECT bodytext FROM $dbT3.tt_content WHERE uid = ?";
        $tt_content = $this->db->sql($sql, ROW_EXPECT_1, [$uid]);

        $qfq = new QuickFormQuery([T3DATA_BODYTEXT => $tt_content[T3DATA_BODYTEXT]], false, false);
        return $qfq->process();

    }


    /**
     * Creates a ZIP Files of all given $files
     *
     * @param array $files
     *
     * @return string ZIP filename - has to be deleted later.
     * @throws \DownloadException
     */
    private function zipFiles(array $files) {

        $zipFile = HelperFile::tempnam();
        if (false === $zipFile) {
            throw new \DownloadException("Error creating output file.", ERROR_DOWNLOAD_CREATE_NEW_FILE);
        }

        $zip = new \ZipArchive();

        if ($zip->open($zipFile, \ZipArchive::CREATE) !== true) {
            throw new \DownloadException("Error creating/opening new empty zip file: $zipFile", ERROR_IO_OPEN);
        }

        $len = strlen(TMP_FILE_PREFIX);
        $ii = 1;
        foreach ($files AS $filename) {
            $localName = substr($filename, strrpos($filename, '/') + 1);

            if (substr($localName, 0, $len) == TMP_FILE_PREFIX) {
                $localName = 'file-' . $ii;
                $ii++;
            }

            $zip->addFile($filename, $localName);
        }
        $zip->close();

        return $zipFile;
    }

    /**
     * $vars[DOWNLOAD_EXPORT_FILENAME] - Optional. '<new filename>'
     * $vars[DOWNLOAD_MODE] - Optional.  file | pdf | excel | thumbnail | monitor - default is a) 'file' in case of only one or b) 'pdf' in case of multiple sources.
     * HTML to PDF | Excel
     *   <i>_id=<Typo3 pageId>
     *   <i>_<key>=<value i>
     * Direct
     *   <i>_file=<filename>
     *
     * @param array $vars [ DOWNLOAD_EXPORT_FILENAME, DOWNLOAD_MODE, SIP_DOWNLOAD_PARAMETER ]
     *
     * @param string $outputMode OUTPUT_MODE_DIRECT | OUTPUT_MODE_FILE | OUTPUT_MODE_COPY_TO_FILE
     * @return string            Filename of the generated file. The filename only points to a real existing filename with  $outputMode=OUTPUT_MODE_FILE | OUTPUT_MODE_COPY_TO_FILE
     * @throws \CodeException
     * @throws \DbException
     * @throws \DownloadException
     * @throws \UserFormException
     * @throws \UserReportException
     * @throws \PhpOffice\PhpSpreadsheet\Exception
     * @throws \PhpOffice\PhpSpreadsheet\Reader\Exception
     * @throws \PhpOffice\PhpSpreadsheet\Writer\Exception
     */
    private function doElements(array $vars, $outputMode) {

        $tmpFiles = array();

        $workDir = $this->store->getVar(SYSTEM_SITE_PATH, STORE_SYSTEM);
        HelperFile::chdir($workDir);

        $downloadMode = $vars[DOWNLOAD_MODE];

        if ($downloadMode == DOWNLOAD_MODE_MONITOR) {
            $monitor = new Monitor();

            return $monitor->dump($vars[TOKEN_L_FILE], $vars[TOKEN_L_TAIL], $vars[TOKEN_L_APPEND]);
        }

        if ($downloadMode == DOWNLOAD_MODE_THUMBNAIL) {
            // Fake $vars control array.
            $pathFilenameThumbnail = $this->doThumbnail($vars[SIP_DOWNLOAD_PARAMETER]);
            $downloadMode = DOWNLOAD_MODE_FILE;
            $vars[SIP_DOWNLOAD_PARAMETER] = TOKEN_FILE . ':' . $pathFilenameThumbnail;
        }

        $elements = explode(PARAM_DELIMITER, $vars[SIP_DOWNLOAD_PARAMETER]);

        // Get all files / content
        $tmpData = array();
        foreach ($elements as $element) {
            $data = '';
            $tmpFiles[] = $this->getElement($element, $downloadMode, $data);
            if (!empty($data)) {
                $tmpData[] = $data;
            }
        }

        // Export, Concat File(s)
        switch ($downloadMode) {
            case DOWNLOAD_MODE_ZIP:
                $filename = $this->zipFiles($tmpFiles);
                if (empty($vars[DOWNLOAD_EXPORT_FILENAME])) {
                    $vars[DOWNLOAD_EXPORT_FILENAME] = basename($filename);
                }
                break;

            case DOWNLOAD_MODE_EXCEL:
                $excel = new Excel();
                $filename = $excel->process($tmpFiles, $tmpData);
                if (empty($vars[DOWNLOAD_EXPORT_FILENAME])) {
                    if (HelperFile::isQfqTemp($filename)) {
                        $vars[DOWNLOAD_EXPORT_FILENAME] = DOWNLOAD_OUTPUT_FILENAME . ".xlsx";
                    } else {
                        $vars[DOWNLOAD_EXPORT_FILENAME] = basename($filename);
                    }
                }
                break;

            case DOWNLOAD_MODE_FILE:
                $filename = $tmpFiles[0];
                if (empty($vars[DOWNLOAD_EXPORT_FILENAME])) {
                    $vars[DOWNLOAD_EXPORT_FILENAME] = basename($filename);
                }
                break;

            case DOWNLOAD_MODE_PDF:

                $filename = $this->concatPdfFiles($tmpFiles);

                // try to find a meaningful filename
                if (empty($vars[DOWNLOAD_EXPORT_FILENAME])) {
                    if (count($tmpFiles) > 1) {
                        $vars[DOWNLOAD_EXPORT_FILENAME] = DOWNLOAD_OUTPUT_FILENAME . ".pdf";
                    } else {
                        if (HelperFile::isQfqTemp($filename)) {
                            $vars[DOWNLOAD_EXPORT_FILENAME] = DOWNLOAD_OUTPUT_FILENAME . ".pdf";
                        } else {
                            $vars[DOWNLOAD_EXPORT_FILENAME] = basename($filename);
                        }
                    }
                }
                break;

            default:
                throw new \DownloadException("Unknown downloadMode: $downloadMode", ERROR_UNKNOWN_MODE);
                break;
        }

        if ($filename != '' && !file_exists($filename)) {
            throw new \DownloadException(json_encode(
                [ERROR_MESSAGE_TO_USER => 'Can\'t read file',
                    ERROR_MESSAGE_TO_DEVELOPER => "File: $filename"]), ERROR_IO_FILE_EXIST);
        }

        switch ($outputMode) {

            case OUTPUT_MODE_FILE:
                break;

            case OUTPUT_MODE_COPY_TO_FILE:
                HelperFile::copy($filename, $vars[DOWNLOAD_EXPORT_FILENAME]);
                HelperFile::cleanTempFiles([$filename]);
                break;

            case OUTPUT_MODE_DIRECT:
                $this->outputFile($filename, $vars[DOWNLOAD_EXPORT_FILENAME]);
                HelperFile::cleanTempFiles([$filename]);
                $filename = '';
                break;

            default:
                throw new \CodeException('Unkown mode: ' . $outputMode, ERROR_UNKNOWN_MODE);
        }

        return $filename;
    }

    /**
     * @param string $urlParam
     * @return string
     * @throws \CodeException
     * @throws \UserFormException
     * @throws \UserReportException
     */
    private function doThumbnail($urlParam) {

        $thumbnail = new Thumbnail();
        $pathFilenameThumbnail = $thumbnail->process($urlParam, THUMBNAIL_VIA_DOWNLOAD);

        return $pathFilenameThumbnail;
    }

    /**
     * Process download as requested in $vars. Output is either directly send to the browser, or a file which has to be deleted later.
     *
     * @param string|array $vars - If $config is an array, take it, else get values from STORE_SIP
     * @param string $outputMode OUTPUT_MODE_DIRECT | OUTPUT_MODE_FILE
     *
     * @return string
     * @throws \CodeException
     * @throws \DbException
     * @throws \DownloadException
     * @throws \UserFormException
     * @throws \UserReportException
     * @throws \PhpOffice\PhpSpreadsheet\Exception
     * @throws \PhpOffice\PhpSpreadsheet\Reader\Exception
     * @throws \PhpOffice\PhpSpreadsheet\Writer\Exception
     */
    public function process($vars, $outputMode = OUTPUT_MODE_DIRECT) {

        if (!is_array($vars)) {
            $vars = $this->store->getStore(STORE_SIP);
        }

        $this->setOutputFormat(empty($vars[DOWNLOAD_OUTPUT_FORMAT]) ? DOWNLOAD_OUTPUT_FORMAT_RAW : $vars[DOWNLOAD_OUTPUT_FORMAT]);

        return $this->doElements($vars, $outputMode);
    }

    /**
     * @param $outputFormat
     */
    private function setOutputFormat($outputFormat) {
        $this->outputFormat = $outputFormat;
    }

    /**
     * @return string - DOWNLOAD_OUTPUT_FORMAT_RAW | DOWNLOAD_OUTPUT_FORMAT_JSON
     */
    public function getOutputFormat() {
        return $this->outputFormat;
    }
}