/*
 * (c) Copyright Ascensio System SIA 2010-2024
 *
 * This program is a free software product. You can redistribute it and/or
 * modify it under the terms of the GNU Affero General Public License (AGPL)
 * version 3 as published by the Free Software Foundation. In accordance with
 * Section 7(a) of the GNU AGPL its Section 15 shall be amended to the effect
 * that Ascensio System SIA expressly excludes the warranty of non-infringement
 * of any third-party rights.
 *
 * This program is distributed WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR  PURPOSE. For
 * details, see the GNU AGPL at: http://www.gnu.org/licenses/agpl-3.0.html
 *
 * You can contact Ascensio System SIA at 20A-6 Ernesta Birznieka-Upish
 * street, Riga, Latvia, EU, LV-1050.
 *
 * The  interactive user interfaces in modified source and object code versions
 * of the Program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU AGPL version 3.
 *
 * Pursuant to Section 7(b) of the License you must retain the original Product
 * logo when distributing the program. Pursuant to Section 7(e) we decline to
 * grant you any rights under trademark law for use of our trademarks.
 *
 * All the Product's GUI elements, including illustrations and icon sets, as
 * well as technical writing content are licensed under the terms of the
 * Creative Commons Attribution-ShareAlike 4.0 International. See the License
 * terms at http://creativecommons.org/licenses/by-sa/4.0/legalcode
 *
 */

'use strict';

const constants = require('./constants');
const {open} = require('node:fs/promises');

function getImageFormatBySignature(buffer) {
  const length = buffer.length;
  //1000 for svg(xml header and creator comment)
  const startText = buffer.toString('ascii', 0, 1000);

  //jpeg
  // Hex: FF D8 FF
  if (3 <= length && 0xff == buffer[0] && 0xd8 == buffer[1] && 0xff == buffer[2]) {
    return constants.AVS_OFFICESTUDIO_FILE_IMAGE_JPG;
  }

  //bmp ( http://ru.wikipedia.org/wiki/BMP )
  //Hex: 42 4D
  //ASCII: BM
  //Hex (position 6) : 00 00
  //Hex (position 26): 01 00
  //Hex (position 28): 00 || 01 || 04 || 08 || 10 || 18 || 20
  //Hex (position 29): 00
  //Hex (position 30): 00 || 01 || 02 || 03 || 04 || 05
  //Hex (position 31): 00 00 00
  if (
    34 <= length &&
    0x42 == buffer[0] &&
    0x4d == buffer[1] &&
    0x00 == buffer[6] &&
    0x00 == buffer[7] &&
    0x01 == buffer[26] &&
    0x00 == buffer[27] &&
    (0x00 == buffer[28] ||
      0x01 == buffer[28] ||
      0x04 == buffer[28] ||
      0x08 == buffer[28] ||
      0x10 == buffer[28] ||
      0x18 == buffer[28] ||
      0x20 == buffer[28]) &&
    0x00 == buffer[29] &&
    (0x00 == buffer[30] || 0x01 == buffer[30] || 0x02 == buffer[30] || 0x03 == buffer[30] || 0x04 == buffer[30] || 0x05 == buffer[30]) &&
    0x00 == buffer[31] &&
    0x00 == buffer[32] &&
    0x00 == buffer[33]
  ) {
    return constants.AVS_OFFICESTUDIO_FILE_IMAGE_BMP;
  }

  //gif
  //Hex: 47 49 46 38
  //ASCII: GIF8
  //or for GIF87a...
  //Hex: 47 49 46 38 37 61
  //ASCII: GIF87a
  //or for GIF89a...
  //Hex: 47 49 46 38 39 61
  //ASCII: GIF89a
  if (0 == startText.indexOf('GIF8')) {
    return constants.AVS_OFFICESTUDIO_FILE_IMAGE_GIF;
  }
  if (0 == startText.indexOf('GIF87a') || 0 == startText.indexOf('GIF89a')) {
    return constants.AVS_OFFICESTUDIO_FILE_IMAGE_GIF;
  }

  //png
  //Hex: 89 50 4E 47 0D 0A 1A 0A 00 00 00 0D 49 48 44 52
  //ASCII: .PNG........IHDR
  if (
    16 <= length &&
    0x89 == buffer[0] &&
    0x50 == buffer[1] &&
    0x4e == buffer[2] &&
    0x47 == buffer[3] &&
    0x0d == buffer[4] &&
    0x0a == buffer[5] &&
    0x1a == buffer[6] &&
    0x0a == buffer[7] &&
    0x00 == buffer[8] &&
    0x00 == buffer[9] &&
    0x00 == buffer[10] &&
    0x0d == buffer[11] &&
    0x49 == buffer[12] &&
    0x48 == buffer[13] &&
    0x44 == buffer[14] &&
    0x52 == buffer[15]
  ) {
    return constants.AVS_OFFICESTUDIO_FILE_IMAGE_PNG;
  }

  //CR2
  //Hex: 49 49 2A 00 10 00 00 00 43 52
  //ASCII: II*.....CR
  if (
    10 <= length &&
    0x49 == buffer[0] &&
    0x49 == buffer[1] &&
    0x2a == buffer[2] &&
    0x00 == buffer[3] &&
    0x10 == buffer[4] &&
    0x00 == buffer[5] &&
    0x00 == buffer[6] &&
    0x00 == buffer[7] &&
    0x43 == buffer[8] &&
    0x52 == buffer[9]
  ) {
    return constants.AVS_OFFICESTUDIO_FILE_IMAGE_CR2;
  }

  //tiff
  //Hex: 49 49 2A 00
  //ASCII:
  //or for big endian
  //Hex: 4D 4D 00 2A
  //ASCII: MM.*
  //or for little endian
  //Hex: 49 49 2A 00
  //ASCII: II*
  if (4 <= length) {
    if (
      (0x49 == buffer[0] && 0x49 == buffer[1] && 0x2a == buffer[2] && 0x00 == buffer[3]) ||
      (0x4d == buffer[0] && 0x4d == buffer[1] && 0x00 == buffer[2] && 0x2a == buffer[3]) ||
      (0x49 == buffer[0] && 0x49 == buffer[1] && 0x2a == buffer[2] && 0x00 == buffer[3])
    ) {
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_TIFF;
    }
  }

  //wmf
  //Hex: D7 CD C6 9A 00 00
  //or for Windows 3.x
  //Hex: 01 00 09 00 00 03
  if (6 <= length) {
    if (
      (0xd7 == buffer[0] && 0xcd == buffer[1] && 0xc6 == buffer[2] && 0x9a == buffer[3] && 0x00 == buffer[4] && 0x00 == buffer[5]) ||
      (0x01 == buffer[0] && 0x00 == buffer[1] && 0x09 == buffer[2] && 0x00 == buffer[3] && 0x00 == buffer[4] && 0x03 == buffer[5])
    ) {
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_WMF;
    }
  }

  //emf ( http://wvware.sourceforge.net/caolan/ora-wmf.html )
  //Hex: 01 00 00 00
  //Hex (position 40): 20 45 4D 46
  if (
    44 <= length &&
    0x01 == buffer[0] &&
    0x00 == buffer[1] &&
    0x00 == buffer[2] &&
    0x00 == buffer[3] &&
    0x20 == buffer[40] &&
    0x45 == buffer[41] &&
    0x4d == buffer[42] &&
    0x46 == buffer[43]
  ) {
    return constants.AVS_OFFICESTUDIO_FILE_IMAGE_EMF;
  }

  //pcx ( http://www.fileformat.info/format/pcx/corion.htm )
  //Hex (position 0): 0A
  //Hex (position 1): 00 || 01 || 02 || 03 || 04 || 05
  //Hex (position 3): 01 || 02 || 04 || 08 ( Bytes per pixel )
  if (
    4 <= length &&
    0x0a == buffer[0] &&
    (0x00 == buffer[1] || 0x01 == buffer[1] || 0x02 == buffer[1] || 0x03 == buffer[1] || 0x04 == buffer[1] || 0x05 == buffer[1]) &&
    (0x01 == buffer[3] || 0x02 == buffer[3] || 0x04 == buffer[3] || 0x08 == buffer[3])
  ) {
    return constants.AVS_OFFICESTUDIO_FILE_IMAGE_PCX;
  }

  //tga ( http://www.fileformat.info/format/tga/corion.htm )
  //DATA TYPE 1-COLOR-MAPPED IMAGES								: Hex (position 1) : 01 01
  //DATA TYPE 2-TRUE-COLOR IMAGES									: Hex (position 1) : 00 02
  //DATA TYPE 3-BLACK AND WHITE(UNMAPPED) IMAGES					: Hex (position 1) : 00 03
  //DATA TYPE 9-RUN-LENGTH ENCODED(RLE),COLOR-MAPPED IMAGES		: Hex (position 1) : 01 09
  //DATA TYPE 10-RUN-LENGTH ENCODED(RLE),TRUE-COLOR IMAGES		: Hex (position 1) : 00 0A
  //DATA TYPE 11-RUN-LENGTH ENCODED(RLE),BLACK AND WHITE IMAGES	: Hex (position 1) : 00 0B
  // + Bytes per pixel											: Hex (position 16): 0x08 || 0x10 || 0x18 || 0x20
  if (
    17 <= length &&
    ((0x01 == buffer[1] && 0x01 == buffer[2]) ||
      (0x00 == buffer[1] && 0x02 == buffer[2]) ||
      (0x00 == buffer[1] && 0x03 == buffer[2]) ||
      (0x01 == buffer[1] && 0x09 == buffer[2]) ||
      (0x00 == buffer[1] && 0x0a == buffer[2]) ||
      (0x00 == buffer[1] && 0x0b == buffer[2])) &&
    (0x08 == buffer[16] || 0x10 == buffer[16] || 0x18 == buffer[16] || 0x20 == buffer[16])
  ) {
    return constants.AVS_OFFICESTUDIO_FILE_IMAGE_TGA;
  }

  //ras
  //Hex: 59 A6 6A 95
  //ASCII: Y
  if (4 <= length && 0x59 == buffer[0] && 0xa6 == buffer[1] && 0x6a == buffer[2] && 0x95 == buffer[3]) {
    return constants.AVS_OFFICESTUDIO_FILE_IMAGE_RAS;
  }

  //ipod
  //(None or Unknown)

  //psd
  //Hex: 38 42 50 53 00 01 00 00 00 00 00 00 00
  //ASCII: 8BPS
  if (
    13 <= length &&
    0x38 == buffer[0] &&
    0x42 == buffer[1] &&
    0x50 == buffer[2] &&
    0x53 == buffer[3] &&
    0x00 == buffer[4] &&
    0x01 == buffer[5] &&
    0x00 == buffer[6] &&
    0x00 == buffer[7] &&
    0x00 == buffer[8] &&
    0x00 == buffer[9] &&
    0x00 == buffer[10] &&
    0x00 == buffer[11] &&
    0x00 == buffer[12]
  ) {
    return constants.AVS_OFFICESTUDIO_FILE_IMAGE_PSD;
  }

  //ico
  //Hex: 00 00 01 00
  if (4 <= length && 0x00 == buffer[0] && 0x00 == buffer[1] && 0x01 == buffer[2] && 0x00 == buffer[3]) {
    return constants.AVS_OFFICESTUDIO_FILE_IMAGE_ICO;
  }

  //svg
  //todo sax parser
  if (-1 !== startText.indexOf('<svg')) {
    return constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_SVG;
  }

  return constants.AVS_OFFICESTUDIO_FILE_UNKNOWN;
}
exports.getFormatFromString = function (ext) {
  if (!ext) {
    return constants.AVS_OFFICESTUDIO_FILE_UNKNOWN;
  }
  switch (ext.toLowerCase()) {
    case 'docx':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOCX;
    case 'doc':
    case 'wps':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOC;
    case 'odt':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_ODT;
    case 'rtf':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_RTF;
    case 'txt':
    case 'xml':
    case 'xslt':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_TXT;
    case 'htm':
    case 'html':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_HTML;
    case 'mht':
    case 'mhtml':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_MHT;
    case 'epub':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_EPUB;
    case 'fb2':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_FB2;
    case 'mobi':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_MOBI;
    case 'docm':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOCM;
    case 'dotx':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOTX;
    case 'dotm':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOTM;
    case 'fodt':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_ODT_FLAT;
    case 'ott':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_OTT;
    case 'oform':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_OFORM;
    case 'docxf':
      return constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOCXF;

    case 'pptx':
      return constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPTX;
    case 'ppt':
    case 'dps':
      return constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPT;
    case 'odp':
      return constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_ODP;
    case 'ppsx':
      return constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPSX;
    case 'pptm':
      return constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPTM;
    case 'ppsm':
      return constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPSM;
    case 'potx':
      return constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_POTX;
    case 'potm':
      return constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_POTM;
    case 'fodp':
      return constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_ODP_FLAT;
    case 'otp':
      return constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_OTP;
    case 'odg':
      return constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_ODG;

    case 'xlsx':
      return constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLSX;
    case 'xls':
    case 'et':
      return constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLS;
    case 'ods':
      return constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_ODS;
    case 'csv':
      return constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_CSV;
    case 'xlsm':
      return constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLSM;
    case 'xltx':
      return constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLTX;
    case 'xltm':
      return constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLTM;
    case 'xlsb':
      return constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLSB;
    case 'fods':
      return constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_ODS_FLAT;
    case 'ots':
      return constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_OTS;

    case 'jpeg':
    case 'jpe':
    case 'jpg':
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_JPG;
    case 'tif':
    case 'tiff':
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_TIFF;
    case 'tga':
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_TGA;
    case 'gif':
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_GIF;
    case 'png':
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_PNG;
    case 'emf':
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_EMF;
    case 'wmf':
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_WMF;
    case 'bmp':
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_BMP;
    case 'cr2':
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_CR2;
    case 'pcx':
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_PCX;
    case 'ras':
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_RAS;
    case 'psd':
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_PSD;
    case 'ico':
      return constants.AVS_OFFICESTUDIO_FILE_IMAGE_ICO;

    case 'pdf':
      return constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_PDF;
    case 'pdfa':
      return constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_PDFA;
    case 'swf':
      return constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_SWF;
    case 'djvu':
      return constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_DJVU;
    case 'xps':
      return constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_XPS;
    case 'svg':
      return constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_SVG;
    case 'htmlr':
      return constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_HTMLR;
    case 'doct':
      return constants.AVS_OFFICESTUDIO_FILE_TEAMLAB_DOCY;
    case 'xlst':
      return constants.AVS_OFFICESTUDIO_FILE_TEAMLAB_XLSY;
    case 'pptt':
      return constants.AVS_OFFICESTUDIO_FILE_TEAMLAB_PPTY;
    case 'ooxml':
      return constants.AVS_OFFICESTUDIO_FILE_OTHER_OOXML;
    case 'odf':
      return constants.AVS_OFFICESTUDIO_FILE_OTHER_ODF;
    case 'vsdx':
      return constants.AVS_OFFICESTUDIO_FILE_DRAW_VSDX;
    case 'vssx':
      return constants.AVS_OFFICESTUDIO_FILE_DRAW_VSSX;
    case 'vstx':
      return constants.AVS_OFFICESTUDIO_FILE_DRAW_VSTX;
    case 'vsdm':
      return constants.AVS_OFFICESTUDIO_FILE_DRAW_VSDM;
    case 'vssm':
      return constants.AVS_OFFICESTUDIO_FILE_DRAW_VSSM;
    case 'vstm':
      return constants.AVS_OFFICESTUDIO_FILE_DRAW_VSTM;
    default:
      return constants.AVS_OFFICESTUDIO_FILE_UNKNOWN;
  }
};
exports.getStringFromFormat = function (format) {
  switch (format) {
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOCX:
      return 'docx';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOC:
      return 'doc';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_ODT:
      return 'odt';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_RTF:
      return 'rtf';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_TXT:
      return 'txt';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_HTML:
      return 'html';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_MHT:
      return 'mht';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_EPUB:
      return 'epub';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_FB2:
      return 'fb2';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_MOBI:
      return 'mobi';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOCM:
      return 'docm';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOTX:
      return 'dotx';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOTM:
      return 'dotm';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_ODT_FLAT:
      return 'fodt';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_OTT:
      return 'ott';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOC_FLAT:
      return 'doc';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOCX_FLAT:
      return 'docx';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_HTML_IN_CONTAINER:
      return 'doc';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOCX_PACKAGE:
      return 'xml';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_OFORM:
      return 'oform';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOCXF:
      return 'docxf';
    case constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_OFORM_PDF:
      return 'pdf';

    case constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPTX:
      return 'pptx';
    case constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPT:
      return 'ppt';
    case constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_ODP:
      return 'odp';
    case constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPSX:
      return 'ppsx';
    case constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPTM:
      return 'pptm';
    case constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPSM:
      return 'ppsm';
    case constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_POTX:
      return 'potx';
    case constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_POTM:
      return 'potm';
    case constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_ODP_FLAT:
      return 'fodp';
    case constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_OTP:
      return 'otp';
    case constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPTX_PACKAGE:
      return 'xml';
    case constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_ODG:
      return 'odg';

    case constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLSX:
      return 'xlsx';
    case constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLS:
      return 'xls';
    case constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_ODS:
      return 'ods';
    case constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_CSV:
      return 'csv';
    case constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLSM:
      return 'xlsm';
    case constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLTX:
      return 'xltx';
    case constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLTM:
      return 'xltm';
    case constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLSB:
      return 'xlsb';
    case constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_ODS_FLAT:
      return 'fods';
    case constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_OTS:
      return 'ots';
    case constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLSX_FLAT:
      return 'xlsx';
    case constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLSX_PACKAGE:
      return 'xml';

    case constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_PDF:
    case constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_PDFA:
      return 'pdf';
    case constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_SWF:
      return 'swf';
    case constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_DJVU:
      return 'djvu';
    case constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_XPS:
      return 'xps';
    case constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_SVG:
      return 'svg';
    case constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_HTMLR:
      return 'htmlr';

    case constants.AVS_OFFICESTUDIO_FILE_OTHER_HTMLZIP:
      return 'zip';
    case constants.AVS_OFFICESTUDIO_FILE_OTHER_JSON:
      return 'json';

    case constants.AVS_OFFICESTUDIO_FILE_IMAGE:
      return 'zip';
    case constants.AVS_OFFICESTUDIO_FILE_IMAGE_JPG:
      return 'jpg';
    case constants.AVS_OFFICESTUDIO_FILE_IMAGE_TIFF:
      return 'tiff';
    case constants.AVS_OFFICESTUDIO_FILE_IMAGE_TGA:
      return 'tga';
    case constants.AVS_OFFICESTUDIO_FILE_IMAGE_GIF:
      return 'gif';
    case constants.AVS_OFFICESTUDIO_FILE_IMAGE_PNG:
      return 'png';
    case constants.AVS_OFFICESTUDIO_FILE_IMAGE_EMF:
      return 'emf';
    case constants.AVS_OFFICESTUDIO_FILE_IMAGE_WMF:
      return 'wmf';
    case constants.AVS_OFFICESTUDIO_FILE_IMAGE_BMP:
      return 'bmp';
    case constants.AVS_OFFICESTUDIO_FILE_IMAGE_CR2:
      return 'cr2';
    case constants.AVS_OFFICESTUDIO_FILE_IMAGE_PCX:
      return 'pcx';
    case constants.AVS_OFFICESTUDIO_FILE_IMAGE_RAS:
      return 'ras';
    case constants.AVS_OFFICESTUDIO_FILE_IMAGE_PSD:
      return 'psd';
    case constants.AVS_OFFICESTUDIO_FILE_IMAGE_ICO:
      return 'ico';

    case constants.AVS_OFFICESTUDIO_FILE_CANVAS_WORD:
    case constants.AVS_OFFICESTUDIO_FILE_CANVAS_SPREADSHEET:
    case constants.AVS_OFFICESTUDIO_FILE_CANVAS_PRESENTATION:
    case constants.AVS_OFFICESTUDIO_FILE_CANVAS_PDF:
      return 'bin';
    case constants.AVS_OFFICESTUDIO_FILE_OTHER_OLD_DOCUMENT:
    case constants.AVS_OFFICESTUDIO_FILE_TEAMLAB_DOCY:
      return 'doct';
    case constants.AVS_OFFICESTUDIO_FILE_TEAMLAB_XLSY:
      return 'xlst';
    case constants.AVS_OFFICESTUDIO_FILE_OTHER_OLD_PRESENTATION:
    case constants.AVS_OFFICESTUDIO_FILE_OTHER_OLD_DRAWING:
    case constants.AVS_OFFICESTUDIO_FILE_TEAMLAB_PPTY:
      return 'pptt';
    case constants.AVS_OFFICESTUDIO_FILE_OTHER_OOXML:
      return 'ooxml';
    case constants.AVS_OFFICESTUDIO_FILE_OTHER_ODF:
      return 'odf';
    case constants.AVS_OFFICESTUDIO_FILE_DRAW_VSDX:
      return 'vsdx';
    case constants.AVS_OFFICESTUDIO_FILE_DRAW_VSSX:
      return 'vssx';
    case constants.AVS_OFFICESTUDIO_FILE_DRAW_VSTX:
      return 'vstx';
    case constants.AVS_OFFICESTUDIO_FILE_DRAW_VSDM:
      return 'vsdm';
    case constants.AVS_OFFICESTUDIO_FILE_DRAW_VSSM:
      return 'vssm';
    case constants.AVS_OFFICESTUDIO_FILE_DRAW_VSTM:
      return 'vstm';
    default:
      return '';
  }
};
exports.getImageFormat = function (ctx, buffer) {
  let format = constants.AVS_OFFICESTUDIO_FILE_UNKNOWN;
  try {
    //signature
    format = getImageFormatBySignature(buffer);
  } catch (e) {
    ctx.logger.error('error getImageFormat: %s', e.stack);
  }
  return format;
};
exports.isDocumentFormat = function (format) {
  return (
    0 !== (format & constants.AVS_OFFICESTUDIO_FILE_DOCUMENT) ||
    format === constants.AVS_OFFICESTUDIO_FILE_CANVAS_WORD ||
    format === constants.AVS_OFFICESTUDIO_FILE_TEAMLAB_DOCY
  );
};
exports.isSpreadsheetFormat = function (format) {
  return (
    0 !== (format & constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET) ||
    format === constants.AVS_OFFICESTUDIO_FILE_CANVAS_SPREADSHEET ||
    format === constants.AVS_OFFICESTUDIO_FILE_TEAMLAB_XLSY
  );
};
exports.isPresentationFormat = function (format) {
  return (
    0 !== (format & constants.AVS_OFFICESTUDIO_FILE_PRESENTATION) ||
    format === constants.AVS_OFFICESTUDIO_FILE_CANVAS_PRESENTATION ||
    format === constants.AVS_OFFICESTUDIO_FILE_TEAMLAB_PPTY
  );
};
exports.isOOXFormat = function (format) {
  return (
    constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOCX === format ||
    constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOCM === format ||
    constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOTX === format ||
    constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOTM === format ||
    constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_OFORM === format ||
    constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_DOCXF === format ||
    constants.AVS_OFFICESTUDIO_FILE_DOCUMENT_OFORM_PDF === format ||
    constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPTX === format ||
    constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPSX === format ||
    constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPTM === format ||
    constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_PPSM === format ||
    constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_POTX === format ||
    constants.AVS_OFFICESTUDIO_FILE_PRESENTATION_POTM === format ||
    constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLSX === format ||
    constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLSM === format ||
    constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLTX === format ||
    constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLTM === format
  );
};
exports.isBrowserEditorFormat = function (format) {
  return (
    constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_PDF === format ||
    constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_PDFA === format ||
    constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_DJVU === format ||
    constants.AVS_OFFICESTUDIO_FILE_CROSSPLATFORM_XPS === format
  );
};
function getDocumentFormatBySignature(buffer) {
  if (!buffer) {
    return constants.AVS_OFFICESTUDIO_FILE_UNKNOWN;
  }
  const text = buffer.toString('latin1');
  // Check for binary DOCT format.
  if (4 <= text.length && text[0] === 'D' && text[1] === 'O' && text[2] === 'C' && text[3] === 'Y') {
    return constants.AVS_OFFICESTUDIO_FILE_CANVAS_WORD;
  }

  // Check for binary XLST format
  if (4 <= text.length && text[0] === 'X' && text[1] === 'L' && text[2] === 'S' && text[3] === 'Y') {
    return constants.AVS_OFFICESTUDIO_FILE_CANVAS_SPREADSHEET;
  }

  // Check for binary PPTT format
  if (4 <= text.length && text[0] === 'P' && text[1] === 'P' && text[2] === 'T' && text[3] === 'Y') {
    return constants.AVS_OFFICESTUDIO_FILE_CANVAS_PRESENTATION;
  }

  // Unknown format
  return constants.AVS_OFFICESTUDIO_FILE_UNKNOWN;
}

/**
 * Определяет формат Office документов по ZIP сигнатуре
 * @param {Buffer} buffer - Буфер с данными файла
 * @returns {number} Константа формата или AVS_OFFICESTUDIO_FILE_UNKNOWN
 */
function getOfficeZipFormatBySignature(buffer) {
  const length = buffer.length;

  // Check ZIP signature (PK header)
  if (
    4 <= length &&
    0x50 == buffer[0] &&
    0x4b == buffer[1] &&
    (0x03 == buffer[2] || 0x05 == buffer[2] || 0x07 == buffer[2]) && // ZIP version markers
    0x04 == buffer[3]
  ) {
    const searchFromEnd = 8192; // Search last 8KB where central directory located
    const startPos = Math.max(0, length - searchFromEnd);

    // Helper function for direct byte search in ZIP central directory
    const searchOfficeFile = filename => {
      const searchBytes = Buffer.from(filename, 'utf8');
      const searchLen = searchBytes.length;
      const endPos = Math.max(0, length - searchLen);

      for (let i = endPos; i >= startPos; i--) {
        let match = true;
        for (let j = 0; j < searchLen; j++) {
          if (buffer[i + j] !== searchBytes[j]) {
            match = false;
            break;
          }
        }
        if (match) return true;
      }
      return false;
    };

    // Check for Excel files
    if (searchOfficeFile('xl/workbook.xml')) {
      return constants.AVS_OFFICESTUDIO_FILE_SPREADSHEET_XLSX;
    }
  }

  return constants.AVS_OFFICESTUDIO_FILE_UNKNOWN;
}

async function getDocumentFormatByFile(file) {
  const firstBytesLen = 100;
  let buffer;
  let fd;
  try {
    fd = await open(file, 'r');
    const stream = fd.createReadStream({start: 0, end: firstBytesLen});
    const chunks = [];
    for await (const chunk of stream) {
      chunks.push(Buffer.from(chunk));
    }
    buffer = Buffer.concat(chunks);
  } finally {
    await fd?.close();
  }
  return getDocumentFormatBySignature(buffer);
}
exports.getDocumentFormatBySignature = getDocumentFormatBySignature;
exports.getDocumentFormatByFile = getDocumentFormatByFile;
exports.getOfficeZipFormatBySignature = getOfficeZipFormatBySignature;