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	<title>Download Link Generator for Drive™</title>
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	<div style="max-width:680px; margin:0 auto; padding-top: 10px; line-height: 130%;">
	
	<h3 style="text-align:center;">Download Link Generator for Drive™</h3>
	
	<p style="text-align:center;"><a href="https://github.com/yasirkula/DownloadLinkGeneratorForGoogleDrive">Source Code</a> | <a href="https://gsuite.google.com/marketplace/app/download_link_generator_for_drive/631283629814">Marketplace</a></p>
	
	<p>This Drive™ extension/add-on lets you generate direct download links for the files in your Drive™ storage. Simply right click the file/folder in your Drive™ and select <i>Open with-&gt;Download Link Generator</i>. When a folder is selected, download links for all the files in that folder are generated. If <i>Download Link Generator</i> button isn't present, then you may first need to authorize this extension by clicking the <i>Authorize</i> button below.</p>
	
	<p>For the generated download links to work everywhere, you need to make the file/folder public. To do this, you can right click the file/folder, select <i>Get link</i> and change visibility from <i>Restricted</i> to <i>Anyone with the link</i>.</p>
	
	<details><summary><b>Privacy Notice <i>(click to expand)</i></b></summary>
	
	<p>This extension accesses the metadata of the selected file/folder and reads its download link from that metadata. All communications with the Drive™ servers is handled via the official <i>Drive™ Javascript API</i> and your Drive™ data is not stored in any way in our databases. This extension's use of information received from Google APIs adheres to <a href="https://developers.google.com/terms/api-services-user-data-policy#additional_requirements_for_specific_api_scopes">Google API Services User Data Policy</a>, including the Limited Use requirements.</p>
	
	<p>Regarding the "<i>See information about your Google Drive files</i>" permission asked during the authorization:</p>
	
	<ul>
		<li><b>The titles and descriptions of your files:</b> names and the download links of the files that you've opened with this extension will be accessed</li>
		<li><b>The names and email addresses of people you share files with:</b> this extension doesn't access this info, this is just a generic text explaining the extents of the permission that this extension asks for. It doesn't necessarily mean that the extension accesses that data</li>
		<li><b>Your folders and how files are organized:</b> when a folder is opened with this extension, names and download links of all files inside that directory will be read by this extension</li>
	</ul>
	
	<p>This extension is hosted at <i>yasirkula.net</i> website and is subject to its <a href="https://yasirkula.net/privacy-policy/">Privacy Policy</a>.</p>
	
	</details>
	
	<p><hr /></p>
	
	<div id="authorize-div" style="display:none">
		<b>You need to authorize access to Drive first:</b> <button id="authorize-button" onclick="handleAuthClick()">Authorize</button>
	</div>
	
	<p id="pre-check-error" style="color:red; display:none;"></p>
	
	<p id="result-filters" style="display:none">
		Display results for: 
		<select onchange="onResultsTypeChanged(this.selectedIndex)">
			<option selected>Download links</option>
			<option>Preview links</option>
			<option>Image embed links</option>
		</select><br />
		
		<input type="checkbox" id="result-table-toggle-input" onchange="onResultsDisplayMethodChanged(this)">
		<label for="result-table-toggle-input">Display results as table</label>
	</p>
	
	</div>
	
	<pre id="status" style="max-width:680px; margin:0 auto;" class="wordwrapped"><b>Status: <span style="color:blue;">connecting to Drive™ servers, please wait... <i>(If nothing happens, please make sure that pop-ups are enabled and try again since authorization is handled via a pop-up)</i></span></b></pre><br />
	
	<div id="result-download-links-holder" style="display:block">
		<pre id="result-download-links" style="display:table; margin:0 auto;"></pre>
		<table id="result-download-links-table" style="display:none; margin:0 auto;"></table><br />
	</div>
	
	<div id="result-preview-links-holder" style="display:none">
		<pre id="result-preview-links" style="display:table; margin:0 auto;"></pre>
		<table id="result-preview-links-table" style="display:none; margin:0 auto;"></table><br />
	</div>
	
	<div id="result-embed-links-holder" style="display:none">
		<pre id="result-embed-links" style="display:table; margin:0 auto;"></pre>
		<table id="result-embed-links-table" style="display:none; margin:0 auto;"></table><br />
	</div>
	
	<pre id="error" style="color: red; max-width:680px; margin:0 auto;" class="wordwrapped"></pre>
	
	<script>
	var CLIENT_ID = 'YOUR_APP_CLIENT_ID';
	var API_KEY = 'YOUR_APP_API_KEY';
	var DISCOVERY_DOC = 'https://www.googleapis.com/discovery/v1/apis/drive/v3/rest';
	var SCOPES = 'https://www.googleapis.com/auth/drive.install https://www.googleapis.com/auth/drive.metadata.readonly';

	var statusText = document.getElementById( 'status' );
	var errorText = document.getElementById( 'error' );
	var preCheckErrorText = document.getElementById( 'pre-check-error' );
	var authorizeButton = document.getElementById( 'authorize-div' );
	var resultFilters = document.getElementById( 'result-filters' );
	
	var resultDownloadLinksHolder = document.getElementById('result-download-links-holder');
	var resultDownloadLinksText = document.getElementById('result-download-links');
	var resultDownloadLinksTable = document.getElementById('result-download-links-table');
	
	var resultPreviewLinksHolder = document.getElementById('result-preview-links-holder');
	var resultPreviewLinksText = document.getElementById('result-preview-links');
	var resultPreviewLinksTable = document.getElementById('result-preview-links-table');
	
	var resultEmbedLinksHolder = document.getElementById('result-embed-links-holder');
	var resultEmbedLinksText = document.getElementById('result-embed-links');
	var resultEmbedLinksTable = document.getElementById('result-embed-links-table');
	
	var userId = "";
	var preCheckError = "You need to right click a file/folder in Drive and select 'Open with->Download Link Generator'.";
	
	var gapiInited = false;
	var gisInited = false;
	var tokenClient;
	
	var openedMultipleFilesAtOnce = false;
	var openedFileIdsStack = [];
	var waitingFoldersStack = [];
	
	function gapiLoaded()
	{
		gapi.load( 'client', initializeGapiClient );
	}
	
	async function initializeGapiClient()
	{
		await gapi.client.init( {
			apiKey: API_KEY,
			discoveryDocs: [DISCOVERY_DOC]
		} );

		gapiInited = true;
		checkAuth();
	}
	
	function gisLoaded()
	{
		tokenClient = google.accounts.oauth2.initTokenClient( {
			client_id: CLIENT_ID,
			scope: SCOPES,
			callback: ''
		} );
		
		gisInited = true;
		checkAuth();
	}
	
	function checkAuth()
	{
		if( !gapiInited || !gisInited )
			return;
		
		var parameters = getQueryVariable( 'state' );
		if( parameters && parameters.length > 0 )
		{
			var parametersJSON = JSON.parse( parameters );
			if( parametersJSON )
			{
				if( parametersJSON.action == "open" )
				{
					if( parametersJSON.ids )
					{
						if( parametersJSON.ids.length > 0 )
						{
							for( var i = 0; i < parametersJSON.ids.length; i++ ) 
								openedFileIdsStack.push( parametersJSON.ids[i] );
							
							openedMultipleFilesAtOnce = ( openedFileIdsStack.length > 1 );
							preCheckError = "";
						}
					}
					else
						preCheckError = "Download links can't be generated for documents created in Drive. You should first convert the document to a downloadable format (e.g. .doc, .docx, .ppt, .xls).";
				}
				else if( parametersJSON.action == "create" && parametersJSON.folderId )
				{
					openedFileIdsStack.push( parametersJSON.folderId );
					preCheckError = "";
				}
				else
					preCheckError = "Invalid state, please try again.";
				
				if( parametersJSON.userId )
					userId = parametersJSON.userId;
			}
		}
		
		tokenClient.callback = handleAuthResult;
		
		tokenClient.requestAccessToken( {
			prompt: 'none',
			hint: userId
		} );
	}
	
	function handleAuthClick()
	{
		tokenClient.requestAccessToken( {
			prompt: 'select_account',
			hint: userId
		} );
		
		return false;
	}

	function handleAuthResult( authResult )
	{
		if( authResult && !authResult.error && google.accounts.oauth2.hasGrantedAllScopes( authResult, 'https://www.googleapis.com/auth/drive.metadata.readonly' ) )
		{
			authorizeButton.style.display = 'none';
			
			if( preCheckError.length > 0 )
			{
				statusText.innerHTML = "";
				preCheckErrorText.style.display = 'block';
				preCheckErrorText.innerHTML = "<b>" + preCheckError + "</b>";
			}
			else
			{
				resultFilters.style.display = 'block';
				statusText.innerHTML = "<b>Status: <span style=\"color:blue;\">generating download link(s), please wait...</span></b>";
				
				getDownloadLinkForOpenedFileOrFolder( openedFileIdsStack.shift() );
			}
		}
		else
		{
			authorizeButton.style.display = 'block';
			preCheckErrorText.style.display = 'none';
			statusText.innerHTML = "";
		}
	}
	
	function getDownloadLinkForOpenedFileOrFolder( fileId )
	{
		var request = gapi.client.drive.files.get({
			'fileId': fileId,
			'fields': "mimeType, name, webContentLink, webViewLink",
			'supportsAllDrives': "true"
		});
		
		request.execute( function( resp )
		{
			if( !resp.error )
			{
				if( resp.mimeType == 'application/vnd.google-apps.folder' )
				{
					// If a single folder is opened, don't start the returned relative paths with this folder's name
					// Otherwise, start the relative paths with the folder's name to distinguish between all opened files and folders
					var relativePath = openedMultipleFilesAtOnce ? (resp.name + "/") : "";
					getDownloadLinksInFolderRecursively( fileId, relativePath );
				}
				else
				{
					resp.id = fileId;
					onFileRetrieved(resp.name, resp, true);
					downloadLinksForOpenedFileOrFolderAreGenerated();
				}
			}
			else
				handleError( resp.error );
		});
	}
	
	function downloadLinksForOpenedFileOrFolderAreGenerated()
	{
		if( openedFileIdsStack.length > 0 )
			getDownloadLinkForOpenedFileOrFolder( openedFileIdsStack.shift() );
		else
			statusText.innerHTML = "<b>Status: <span style=\"color:green;\">finished</span></b>";
	}
	
	function getDownloadLinksInFolderRecursively( folderId, relativePath )
	{
		var getFiles = function(request) 
		{
			request.execute(function(resp) 
			{
				if( !resp.error )
				{
					var files = resp.files;
					if (files && files.length > 0) 
					{
						for (var i = 0; i < files.length; i++) 
							onFileRetrieved(relativePath + files[i].name, files[i], false);
					}
					
					if (resp.nextPageToken)
						getFiles(getListFilesRequest(folderId, false, resp.nextPageToken));
					else
					{
						if( waitingFoldersStack.length > 0 )
						{
							var folderToEnter = waitingFoldersStack.shift();
							console.log( "Entering folder: " + folderToEnter._relativePath );
							getDownloadLinksInFolderRecursively( folderToEnter._id, folderToEnter._relativePath );
						}
						else
							downloadLinksForOpenedFileOrFolderAreGenerated();
					}
				}
				else
					handleError( resp.error );
			});
		};
		
		var getFolders = function(request) 
		{
			request.execute(function(resp) 
			{
				if( !resp.error )
				{
					var folders = resp.files;
					if (folders && folders.length > 0) 
					{
						for (var i = 0; i < folders.length; i++) 
						{
							var folder = folders[i];
							if (folder.webViewLink)
								onPreviewLinkRetrieved(relativePath + folder.name + "/", folder.webViewLink);
							
							waitingFoldersStack.push( { _id: folder.id, _relativePath: relativePath + folder.name + "/" } );
						}
					}
					
					if (resp.nextPageToken)
						getFolders(getListFilesRequest(folderId, true, resp.nextPageToken));
					else
						getFiles(getListFilesRequest(folderId, false, null));
				}
				else
					handleError( resp.error );
			});
		};
		
		getFolders(getListFilesRequest(folderId, true, null));
	}
	
	function getListFilesRequest(folderId, listFolders, nextPageToken)
	{
		var query =
		{
			'q': "trashed=false and '" + folderId + "' in parents and mimeType " + (listFolders ? "=" : "!=") + " 'application/vnd.google-apps.folder'",
			'pageSize': 1000,
			'fields': "nextPageToken, files(id, name, webViewLink" + (listFolders ? "" : ", webContentLink") + ")",
			'includeItemsFromAllDrives': "true",
			'supportsAllDrives': "true"
		};
		
		if (nextPageToken != null)
			query.pageToken = nextPageToken;
		
		return gapi.client.drive.files.list(query);
	}
	
	function handleError( err )
	{
		console.log( "ERROR: " + JSON.stringify( err ) );
		
		var reason = "";
		var msg = "";
		
		if( err.errors && err.errors.length > 0 )
		{
			reason = err.errors[0].reason;
			msg = err.errors[0].message;
		}
		else if( err.data && err.data.length > 0 )
		{
			reason = err.data[0].reason;
			msg = err.data[0].message;
		}
		
		if( err.code == 401 )
		{
			handleAuthClick();
		}
		else if( err.code == 403 )
		{
			if( reason == "rateLimitExceeded" || reason == "userRateLimitExceeded" )
				errorText.innerHTML = "Too many requests; try again in a minute.";
			else if( reason == "dailyLimitExceeded" )
				errorText.innerHTML = "App reached daily limit (just wow O_O ); service will be available tomorrow.";
			else
				errorText.innerHTML = err.code + ": " + err.message + "(" + reason + ": " + msg + ")\r\n";
		}
		else
		{
			errorText.innerHTML = err.code + ": " + err.message + " (" + reason + ": " + msg + ")\r\n";
		}
		
		statusText.innerHTML = "<b>Status: <span style=\"color:red;\">see error log below</span></b>";
	}
	
	function onFileRetrieved(relativePath, file, showWarningForUnavailableFiles)
	{
		if (file.webContentLink || showWarningForUnavailableFiles)
			onDownloadLinkRetrieved(relativePath, file.webContentLink);
		if (file.webViewLink || showWarningForUnavailableFiles)
			onPreviewLinkRetrieved(relativePath, file.webViewLink);
		if (file.id || showWarningForUnavailableFiles)
			onEmbedLinkRetrieved(relativePath, file.id ? ("https://lh3.googleusercontent.com/d/" + file.id) : null); // Credit: https://stackoverflow.com/a/70143719/2373034
	}
	
	function onDownloadLinkRetrieved(relativePath, link)
	{
		updateResult(relativePath, link, resultDownloadLinksText, resultDownloadLinksTable);
	}
	
	function onPreviewLinkRetrieved(relativePath, link)
	{
		updateResult(relativePath, link, resultPreviewLinksText, resultPreviewLinksTable);
	}
	
	function onEmbedLinkRetrieved(relativePath, link)
	{
		updateResult(relativePath, link, resultEmbedLinksText, resultEmbedLinksTable);
	}
	
	function updateResult(relativePath, link, resultText, resultTable)
	{
		var newRow = resultTable.insertRow(-1);
		newRow.insertCell(0).innerHTML = "<pre>" + relativePath + "</pre>";
		if (link != null)
		{
			resultText.innerHTML += relativePath + " <a href=\"" + link + "\">" + link + "</a>\r\n";
			newRow.insertCell(1).innerHTML = "<pre><a href=\"" + link + "\">" + link + "</a></pre>";
		}
		else
		{
			resultText.innerHTML += relativePath + " Link couldn't be fetched\r\n";
			newRow.insertCell(1).innerHTML = "<pre>Link couldn't be fetched</pre>";
		}
	}
	
	function onResultsDisplayMethodChanged(checkbox)
	{
		resultDownloadLinksText.style.display = resultPreviewLinksText.style.display = resultEmbedLinksText.style.display = checkbox.checked ? 'none' : 'table';
		resultDownloadLinksTable.style.display = resultPreviewLinksTable.style.display = resultEmbedLinksTable.style.display = checkbox.checked ? 'table' : 'none';
	}
	
	function onResultsTypeChanged(resultsType)
	{
		resultDownloadLinksHolder.style.display = (resultsType == "0") ? 'block' : 'none';
		resultPreviewLinksHolder.style.display = (resultsType == "1") ? 'block' : 'none';
		resultEmbedLinksHolder.style.display = (resultsType == "2") ? 'block' : 'none';
	}
	
	// Credit: https://css-tricks.com/snippets/javascript/get-url-variables/
	function getQueryVariable( variable )
	{
		var query = window.location.search;
		if( !query || query.length === 0 )
			return "";
		
		var vars = query.substring( 1 ).split( "&" );
		for( var i = 0; i < vars.length; i++ )
		{
			var pair = vars[i].split( "=" );
			if( pair[0] == variable )
				return decodeURIComponent( pair[1].replace( /\+/g, ' ' ) );
		}
		
		return "";
	}
	</script>
	<script async defer src="https://apis.google.com/js/api.js"
		onload="this.onload=function(){};gapiLoaded()"
		onreadystatechange="if (this.readyState === 'complete') this.onload()">
	</script>
	<script async defer src="https://accounts.google.com/gsi/client"
		onload="this.onload=function(){};gisLoaded()"
		onreadystatechange="if (this.readyState === 'complete') this.onload()">
	</script>
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