Support downloading of multiple photos.

This commit adds a contextmenu entry to download a single and multiple
photos via selection. So far, not for guests.

php/Access/Admin.php

@@ -61,6 +61,7 @@ final class Admin extends Access {
 
 			// $_GET functions
 			case 'Album::getArchive':       self::getAlbumArchiveAction(); break;
+			case 'Photo::getArchive':       self::getPhotoArchiveAction(); break;
 			case 'Photo::getPhoto':         self::getPhotoFileAction(); break;
 
 		}
@@ -341,6 +342,15 @@ final class Admin extends Access {
 
 	}
 
+	private static function getPhotoArchiveAction() {
+
+		Validator::required(isset($_GET['photoIDs']), __METHOD__);
+
+		$photo = new Photo($_GET['photoIDs']);
+		$photo->getArchive();
+
+	}
+
 	private static function getPhotoFileAction() {
 
 		Validator::required(isset($_GET['photoID']), __METHOD__);

php/Modules/Photo.php

@@ -948,6 +948,33 @@ final class Photo {
 
 	}
 
+	/**
+	 * Starts a download of photos.
+	 * @return resource|boolean Sends a ZIP-file or returns false on failure.
+	 */
+	public function getArchive() {
+
+		// Check dependencies
+		Validator::required(isset($this->photoIDs), __METHOD__);
+
+		// Call plugins
+		Plugins::get()->activate(__METHOD__, 0, func_get_args());
+
+		$archive = new Archive('Photos');
+
+		$query   = Database::prepare(Database::get(), 'SELECT title, url FROM ? WHERE id IN (?)', array(LYCHEE_TABLE_PHOTOS, $this->photoIDs));
+
+        if (!$archive->addPhotos('', $query)) return false;
+
+		$archive->send();
+
+		// Call plugins
+		Plugins::get()->activate(__METHOD__, 1, func_get_args());
+
+		return true;
+
+	}
+
 	/**
 	 * Sets the title of a photo.
 	 * @return boolean Returns true when successful.

src/scripts/contextMenu.js

@@ -244,6 +244,7 @@ contextMenu.photo = function(photoID, e) {
 	// in order to keep the selection
 
 	let items = [
+		{ title: build.iconic('cloud-download') + 'Download', fn: () => photo.getPhoto(photoID) },
 		{ title: build.iconic('star') + 'Star', fn: () => photo.setStar([ photoID ]) },
 		{ title: build.iconic('tag') + 'Tags', fn: () => photo.editTags([ photoID ]) },
 		{ },
@@ -268,6 +269,7 @@ contextMenu.photoMulti = function(photoIDs, e) {
 	// in order to keep the selection and multiselect
 
 	let items = [
+		{ title: build.iconic('cloud-download') + 'Download All', fn: () => photo.getArchive(photoIDs) },
 		{ title: build.iconic('star') + 'Star All', fn: () => photo.setStar(photoIDs) },
 		{ title: build.iconic('tag') + 'Tag All', fn: () => photo.editTags(photoIDs) },
 		{ },

src/scripts/photo.js

@@ -647,6 +647,20 @@ photo.getPhoto = function(photoID) {
 
 }
 
+photo.getArchive = function(photoIDs) {
+
+	let link
+	let url = `${ api.path }?function=Photo::getArchive&photoIDs=${ photoIDs.join(',') }`
+
+	if (location.href.indexOf('index.html')>0) link = location.href.replace(location.hash, '').replace('index.html', url)
+	else                                       link = location.href.replace(location.hash, '') + url
+
+	if (lychee.publicMode===true) link += `&password=${ encodeURIComponent(password.value) }`
+
+	location.href = link
+
+}
+
 photo.getDirectLink = function() {
 
 	let url = ''