<?php
/**
 * Copyright (C) 2013-2024 Combodo SAS
 *
 * This file is part of iTop.
 *
 * iTop is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * iTop is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 */

use Combodo\iTop\Application\WebPage\WebPage;
use Combodo\iTop\Service\Events\EventData;
use Combodo\iTop\Service\Events\EventService;


/**
 * ormDocument
 * encapsulate the behavior of a binary data set that will be stored an attribute of class AttributeBlob 
 *
 * @package     itopORM
 */
class ormDocument
{
	/**
	 * @var string For content that should be displayed in the browser
	 * @link https://developer.mozilla.org/fr/docs/Web/HTTP/Headers/Content-Disposition#syntaxe
	 * @since 3.1.0
	 */
	public const ENUM_CONTENT_DISPOSITION_INLINE = 'inline';
	/**
	 * @var string For content that should be downloaded on the device. Mind that "attachment" Content-Disposition has nothing to do with the "Attachment" class from the DataModel.
	 * @link https://developer.mozilla.org/fr/docs/Web/HTTP/Headers/Content-Disposition#syntaxe
	 * @since 3.1.0
	 */
	public const ENUM_CONTENT_DISPOSITION_ATTACHMENT = 'attachment';

	/**
	 * @var int Default downloads count of the document, should always be 0.
	 * @since 3.1.0
	 */
	public const DEFAULT_DOWNLOADS_COUNT = 0;
	private static $aKnownExtensions = [
		'xlsx' => 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
		'xltx' => 'application/vnd.openxmlformats-officedocument.spreadsheetml.template',
		'potx' => 'application/vnd.openxmlformats-officedocument.presentationml.template',
		'ppsx' => 'application/vnd.openxmlformats-officedocument.presentationml.slideshow',
		'pptx' => 'application/vnd.openxmlformats-officedocument.presentationml.presentation',
		'sldx' => 'application/vnd.openxmlformats-officedocument.presentationml.slide',
		'docx' => 'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
		'dotx' => 'application/vnd.openxmlformats-officedocument.wordprocessingml.template',
		'xlam' => 'application/vnd.ms-excel.addin.macroEnabled.12',
		'xlsb' => 'application/vnd.ms-excel.sheet.binary.macroEnabled.12',
		'jpg'  => 'image/jpeg',
		'jpeg' => 'image/jpeg',
		'gif'  => 'image/gif',
		'png'  => 'image/png',
		'pdf'  => 'application/pdf',
		'doc'  => 'application/msword',
		'dot'  => 'application/msword',
		'xls'  => 'application/vnd.ms-excel',
		'ppt'  => 'application/vnd.ms-powerpoint',
		'vsd'  => 'application/x-visio',
		'vdx'  => 'application/visio.drawing',
		'odt'  => 'application/vnd.oasis.opendocument.text',
		'ods'  => 'application/vnd.oasis.opendocument.spreadsheet',
		'odp'  => 'application/vnd.oasis.opendocument.presentation',
		'zip'  => 'application/zip',
		'txt'  => 'text/plain',
		'htm'  => 'text/html',
		'html' => 'text/html',
		'exe'  => 'application/octet-stream',
	];

	public static function GetKnownExtensions(): array
	{
		return self::$aKnownExtensions;
	}

	protected $m_data;
	protected $m_sMimeType;
	protected $m_sFileName;
	/**
	 * @var int $m_iDownloadsCount Number of times the document has been downloaded (through the standard API!). Note that download from the browser's cache won't appear.
	 * @since 3.1.0
	 */
	private $m_iDownloadsCount;

	/**
	 * Constructor
	 *
	 * @param null $data
	 * @param string $sMimeType
	 * @param string $sFileName
	 * @param int $iDownloadsCount
	 *
	 * @since 3.1.0 N°2889 Add $iDownloadsCount parameter
	 */
	public function __construct($data = null, $sMimeType = 'text/plain', $sFileName = '', $iDownloadsCount = self::DEFAULT_DOWNLOADS_COUNT)
	{
		$this->m_data = $data;
		$this->m_sMimeType = $sMimeType;
		$this->m_sFileName = $sFileName;
		$this->m_iDownloadsCount = $iDownloadsCount;
	}

	/**
	 * @param string $sPath Absolute path of the document to read
	 *
	 * @return \ormDocument
	 * @throws \Exception
	 */
	public static function FromFile(string $sPath): ormDocument
	{
		$sPath = utils::RealPath($sPath, APPROOT);
		if (false === $sPath) {
			throw new Exception("Failed to load the file '$sPath'. The file does not exist or the current process is not allowed to access it.");
		}
		$sData = @file_get_contents($sPath);
		if (false === $sData) {
			throw new Exception("Failed to load the file '$sPath'. The file does not exist or the current process is not allowed to access it.");
		}
		$sExtension = strtolower(pathinfo($sPath, PATHINFO_EXTENSION));
		$sFileName = basename($sPath);

		$sMimeType = 'text/plain';
		if (array_key_exists($sExtension, ormDocument::$aKnownExtensions)) {
			$sMimeType = ormDocument::$aKnownExtensions[$sExtension];
		} else if (extension_loaded('fileinfo')) {
			$fInfo = new finfo(FILEINFO_MIME);
			$sMimeType = $fInfo->file($sPath);
		}

		return new ormDocument($sData, $sMimeType, $sFileName);
	}

	public function __toString()
	{
	    if($this->IsEmpty()) return '';

		return MyHelpers::beautifulstr($this->m_data, 100, true);
	}

	public function IsEmpty()
	{
		return ($this->m_data == null);
	}

	/**
	 * @param \ormDocument $oCompared
	 *
	 * @return bool True if the current ormDocument is equals to $oCompared EXCEPT for its download count. False if any other property is different OR if count is the same.
	 * @since 3.1.0 N°6502
	 */
	public function EqualsExceptDownloadsCount(ormDocument $oCompared): bool
	{
		// First checking equality on others properties
		if ($oCompared->GetData() !== $this->GetData()) {
			return false;
		}
		if ($oCompared->GetMimeType() !== $this->GetMimeType()) {
			return false;
		}
		if ($oCompared->GetFileName() !== $this->GetFileName()) {
			return false;
		}

		// Finally check equality of the download count
		if ($oCompared->GetDownloadsCount() === $this->GetDownloadsCount()) {
			return false;
		} else {
			return true;
		}
	}
	
	public function GetMimeType()
	{
		return $this->m_sMimeType;
	}
	public function GetMainMimeType()
	{
		$iSeparatorPos = strpos($this->m_sMimeType, '/');
		if ($iSeparatorPos > 0)
		{
			return substr($this->m_sMimeType, 0, $iSeparatorPos);
		}
		return $this->m_sMimeType;
	}

	/**
	 * @return int size in bits
	 * @uses strlen which returns the no of bits used
	 * @since 2.7.0
	 */
	public function GetSize()
	{
		return strlen($this->m_data);
	}

	/**
	 * @param int $precision
	 *
	 * @return string
	 * @uses utils::BytesToFriendlyFormat()
	 */
	public function GetFormattedSize($precision = 2)
	{
		$bytes = $this->GetSize();
		return utils::BytesToFriendlyFormat($bytes, $precision);
	}
	public function GetData()
	{
		return $this->m_data;
	}

	public function GetFileName()
	{
		return $this->m_sFileName;
	}

	/**
	 * @see static::DownloadDocument()
	 * @see static::$m_iDownloadsCount
	 * @return int Number of times the document has been downloaded (through the standard API!)
	 * @since 3.1.0
	 */
	public function GetDownloadsCount(): int
	{
		// Force cast to get 0 instead of null on fields prior to the features that have never been downloaded.
		return (int) $this->m_iDownloadsCount;
	}

	/**
	 * Increase the number of downloads of the document by $iNumber
	 *
	 * @param int $iNumber Step to increase the counter with, default is 1.
	 * @return void
	 * @since 3.1.0
	 */
	public function IncreaseDownloadsCount($iNumber = 1): void
	{
		$this->m_iDownloadsCount += $iNumber;
	}

	public function GetAsHTML()
	{
		$sResult = '';
		if ($this->IsEmpty()) {
			// If the filename is not empty, display it, this is used
			// by the creation wizard while the file has not yet been uploaded
			$sResult = utils::EscapeHtml($this->GetFileName());
		} else {
			$data = $this->GetData();
			$sSize = utils::BytesToFriendlyFormat(strlen($data));
			$iDownloadsCount = $this->GetDownloadsCount();
			$sDownloadsCountForHtml = utils::HtmlEntities(Dict::Format('Core:ormValue:ormDocument:DownloadsCount', $iDownloadsCount));
			$sDownloadsCountTooltipForHtml = utils::HtmlEntities(Dict::Format('Core:ormValue:ormDocument:DownloadsCount+', $iDownloadsCount));
			$sResult = utils::EscapeHtml($this->GetFileName()).' ('.$sSize.' / '.$sDownloadsCountForHtml.' <i class="fas fa-cloud-download-alt" data-tooltip-content="'.$sDownloadsCountTooltipForHtml.'"></i>)<br/>';
		}
		return $sResult;
	}
		
	/**
	 * Returns an hyperlink to display the document *inline*
	 * @return string
	 */	 	 	
	public function GetDisplayLink($sClass, $Id, $sAttCode)
	{
		$sUrl = $this->GetDisplayURL($sClass, $Id, $sAttCode);

		return "<a href=\"$sUrl\" target=\"_blank\" >".utils::EscapeHtml($this->GetFileName())."</a>\n";
	}
	
	/**
	 * Returns an hyperlink to download the document (content-disposition: attachment)
	 * @return string
	 */	 	 	
	public function GetDownloadLink($sClass, $Id, $sAttCode)
	{
		$sUrl = $this->GetDownloadURL($sClass, $Id, $sAttCode);

		return "<a href=\"$sUrl\">".utils::EscapeHtml($this->GetFileName())."</a>\n";
	}

	/**
	 * Returns an URL to display a document like an image
	 * @return string
	 */
	public function GetDisplayURL($sClass, $Id, $sAttCode)
	{
		$sSignature = $this->GetSignature();
		// TODO: When refactoring this with the URLMaker system, mind to also change calls in the portal (look for the "p_object_document_display" route)
		return utils::GetAbsoluteUrlAppRoot() . "pages/ajax.render.php?operation=display_document&class=$sClass&id=$Id&field=$sAttCode&s=$sSignature&cache=86400";
	}

	/**
	 * Returns an URL to download a document like an image (uses HTTP caching)
	 * @return string
	 */
	public function GetDownloadURL($sClass, $Id, $sAttCode)
	{
		// Compute a signature to reset the cache anytime the data changes (this is acceptable if used only with icon files)
		$sSignature = $this->GetSignature();
		// TODO: When refactoring this with the URLMaker system, mind to also change calls in the portal (look for the "p_object_document_display" route)
		return utils::GetAbsoluteUrlAppRoot() . "pages/ajax.document.php?operation=download_document&class=$sClass&id=$Id&field=$sAttCode&s=$sSignature&cache=86400";
	}

	public function IsPreviewAvailable()
	{
		$bRet = false;
		switch($this->GetMimeType())
		{
			case 'image/png':
			case 'image/jpg':
			case 'image/jpeg':
			case 'image/gif':
			case 'image/bmp':
			case 'image/svg+xml':
			$bRet = true;
			break;
		}
		return $bRet;
	}

	/**
	 * Downloads a document to the browser, either as 'inline' or 'attachment'
	 *
	 * @param WebPage $oPage The web page for the output
	 * @param string $sClass Class name of the object
	 * @param mixed $id Identifier of the object
	 * @param string $sAttCode Name of the attribute containing the document to download
	 * @param string $sContentDisposition Either 'inline' or 'attachment'
	 * @param string $sSecretField The attcode of the field containing a "secret" to be provided in order to retrieve the file
	 * @param string $sSecretValue The value of the secret to be compared with the value of the attribute $sSecretField
	 *
	 * @return void
	 */
	public static function DownloadDocument(WebPage $oPage, $sClass, $id, $sAttCode, $sContentDisposition = 'attachment', $sSecretField = null, $sSecretValue = null)
	{
		try
		{
			$oObj = MetaModel::GetObject($sClass, $id, false, false);
			if (!is_object($oObj))
			{
				// If access to the document is not granted, check if the access to the host object is allowed
				$oObj = MetaModel::GetObject($sClass, $id, false, true);
				if ($oObj instanceof Attachment) {
					$sItemClass = $oObj->Get('item_class');
					$sItemId = $oObj->Get('item_id');
					$oHost = MetaModel::GetObject($sItemClass, $sItemId, false, false);
					if (!is_object($oHost)) {
						$oObj = null;
					}
				}
				if (!is_object($oObj)) {
					throw new Exception("Invalid id ($id) for class '$sClass' - the object does not exist or you are not allowed to view it");
				}
			}
			if (($sSecretField != null) && ($oObj->Get($sSecretField) != $sSecretValue))
			{
				usleep(200);
				throw new Exception("Invalid secret for class '$sClass' - the object does not exist or you are not allowed to view it");
			}
			/** @var \ormDocument $oDocument */
			$oDocument = $oObj->Get($sAttCode);
			if (is_object($oDocument))
			{
				$aEventData = array(
					'debug_info' => $oDocument->GetFileName(),
					'object' => $oObj,
					'att_code' => $sAttCode,
					'document' => $oDocument,
					'content_disposition' => $sContentDisposition,
					);
				EventService::FireEvent(new EventData(\EVENT_DOWNLOAD_DOCUMENT, $sClass, $aEventData));
				$oPage->TrashUnexpectedOutput();
				$oPage->SetContentType($oDocument->GetMimeType());
				$oPage->SetContentDisposition($sContentDisposition,$oDocument->GetFileName());
				$oPage->add($oDocument->GetData());

				// Update downloads count only when content disposition is set to "attachment" as other disposition are to display the document within the page
				if($sContentDisposition === static::ENUM_CONTENT_DISPOSITION_ATTACHMENT) {
					$oDocument->IncreaseDownloadsCount();
					$oObj->Set($sAttCode, $oDocument);
					// $oObj can be a \DBObject or \cmdbAbstractObject so we ahve to protect it
					if (method_exists($oObj, 'AllowWrite')) {
						// AllowWrite method is implemented in cmdbAbstractObject, but $oObject could be a DBObject or CMDBObject
						$oObj->AllowWrite();
					}
					$oObj->DBUpdate();
				}
			}
		}
		catch(Exception $e)
		{
			$oPage->p($e->getMessage());
		}
	}

	/**
	 * Resize an image so that it fits in the given dimensions
	 * @param int $iMaxImageWidth Maximum width for the resized image
	 * @param int $iMaxImageHeight Maximum height for the resized image
	 * @param array|null $aFinalDimensions Image dimensions after resizing or null if unable to read the image
	 * @return ormDocument The resampled image
	 *
	 */
	public function ResizeImageToFit(int $iMaxWidth, int $iMaxHeight, array|null &$aFinalDimensions = null) : static
	{
		$aFinalDimensions = null;
		// If gd extension is not loaded, we put a warning in the log and return the image as is
		if (extension_loaded('gd') === false) {
			IssueLog::Warning('Image could not be resized as the "gd" extension does not seem to be loaded. Its dimensions will remain the same instead of ' . $iMaxWidth . 'x' . $iMaxHeight);
			return $this;
		}
		$oGdImage = false;
		switch($this->GetMimeType()) {
			case 'image/gif':
			case 'image/jpeg':
			case 'image/png':
				$oGdImage = @imagecreatefromstring($this->GetData());
				break;
			default:
				// Unsupported image type, return the image as-is
				return $this;
		}

		if ($oGdImage === false) {
			IssueLog::Warning('Image could not be resized as . It will remain as imagecreatefromstring could not read its data.Its dimensions will remain the same instead of ' . $iMaxWidth . 'x' . $iMaxHeight);
			return $this;
		}

		$iWidth = imagesx($oGdImage);
		$iHeight = imagesy($oGdImage);

		if ( ($iMaxWidth === 0 || $iWidth <= $iMaxWidth) && ($iMaxHeight === 0 || $iHeight <= $iMaxHeight)) {
			// No need to resize
			$aFinalDimensions = [
				'width' => $iWidth,
				'height' =>$iHeight
			];
			return $this;
		}

		$fScale = 1.0;
		if ($iMaxWidth > 0) {
			$fScale = min($fScale, $iMaxWidth / $iWidth);
		}
		if ($iMaxHeight > 0) {
			$fScale = min($fScale, $iMaxHeight / $iHeight);
		}
		$iNewWidth = (int)($iWidth * $fScale);
		$iNewHeight = (int)($iHeight * $fScale);

		$oNewGdImage = imagecreatetruecolor($iNewWidth, $iNewHeight);


		$aFinalDimensions = [
			'width' => $iNewWidth,
			'height' =>$iNewHeight
		];

		// Preserve transparency
		if($this->GetMimeType() == "image/gif" || $this->GetMimeType() == "image/png") {
			imagecolortransparent($oNewGdImage, imagecolorallocatealpha($oNewGdImage, 0, 0, 0, 127));
			imagealphablending($oNewGdImage, false);
			imagesavealpha($oNewGdImage, true);
		}
		imagecopyresampled($oNewGdImage, $oGdImage, 0, 0, 0, 0, $iNewWidth, $iNewHeight, $iWidth, $iHeight);

		ob_start();
		switch ($this->GetMimeType()) {
			case 'image/gif':
			imagegif($oNewGdImage); // send image to output buffer
			break;

			case 'image/jpeg':
			imagejpeg($oNewGdImage, null, 80); // null = send image to output buffer, 80 = good quality
			break;

			case 'image/png':
			imagepng($oNewGdImage, null, 5); // null = send image to output buffer, 5 = medium compression
			break;
		}
		$oResampledImage = new ormDocument(ob_get_contents(), $this->GetMimeType(), $this->GetFileName());
		@ob_end_clean();

		imagedestroy($oGdImage);
		imagedestroy($oNewGdImage);

		return $oResampledImage;

	}

	/**
	 * @return string
	 */
	public function GetSignature(): string
	{
		return md5($this->GetData() ?? '');
	}


}