simplified "go back" functionality

backend/src/config.js

@@ -18,7 +18,8 @@ const config = {
     secretAccessKey: process.env.AWS_SECRET_ACCESS_KEY || '',
     prefix: process.env.AWS_S3_PREFIX || 'afeefb9d49f5b7977577876b99532ac7',
     // Timeout configuration (in milliseconds)
-    connectionTimeout: parseInt(process.env.AWS_S3_CONNECTION_TIMEOUT, 10) || 5000,
+    connectionTimeout:
+      parseInt(process.env.AWS_S3_CONNECTION_TIMEOUT, 10) || 5000,
     requestTimeout: parseInt(process.env.AWS_S3_REQUEST_TIMEOUT, 10) || 30000,
     // Retry configuration
     maxAttempts: parseInt(process.env.AWS_S3_MAX_ATTEMPTS, 10) || 3,
@@ -26,7 +27,8 @@ const config = {
     maxSockets: parseInt(process.env.AWS_S3_MAX_SOCKETS, 10) || 50,
     keepAlive: process.env.AWS_S3_KEEP_ALIVE !== 'false',
     // Presigned URL expiry (in seconds)
-    presignExpirySeconds: parseInt(process.env.AWS_S3_PRESIGN_EXPIRY, 10) || 3600,
+    presignExpirySeconds:
+      parseInt(process.env.AWS_S3_PRESIGN_EXPIRY, 10) || 3600,
   },
   bcrypt: {
     saltRounds: 12,

backend/src/db/api/base.api.js

@@ -131,7 +131,9 @@ class GenericDBApi {
     }
 
     // Apply custom transformers
-    for (const [field, transformer] of Object.entries(this.FIELD_TRANSFORMERS)) {
+    for (const [field, transformer] of Object.entries(
+      this.FIELD_TRANSFORMERS,
+    )) {
       if (mapped[field] !== undefined) {
         mapped[field] = transformer(mapped[field]);
       }

backend/src/db/api/projects.js

@@ -35,14 +35,7 @@ class ProjectsDBApi extends GenericDBApi {
   }
 
   static get CSV_FIELDS() {
-    return [
+    return ['id', 'name', 'slug', 'description', 'logo_url', 'createdAt'];
-      'id',
-      'name',
-      'slug',
-      'description',
-      'logo_url',
-      'createdAt',
-    ];
   }
 
   static get AUTOCOMPLETE_FIELD() {
@@ -63,7 +56,8 @@ class ProjectsDBApi extends GenericDBApi {
       favicon_url: data.favicon_url || null,
       og_image_url: data.og_image_url || null,
       design_width: data.design_width !== undefined ? data.design_width : null,
-      design_height: data.design_height !== undefined ? data.design_height : null,
+      design_height:
+        data.design_height !== undefined ? data.design_height : null,
     };
   }
 

backend/src/db/api/tour_pages.js

@@ -94,8 +94,7 @@ class Tour_pagesDBApi extends GenericDBApi {
         data.background_video_end_time !== undefined
           ? data.background_video_end_time
           : null,
-      design_width:
+      design_width: data.design_width !== undefined ? data.design_width : null,
-        data.design_width !== undefined ? data.design_width : null,
       design_height:
         data.design_height !== undefined ? data.design_height : null,
       requires_auth: data.requires_auth || false,

backend/src/db/migrations/20260331054340-remove-duplicate-element-type-defaults.js

@@ -60,6 +60,8 @@ module.exports = {
 
   async down(_queryInterface, _Sequelize) {
     // Cannot restore deleted duplicates
-    console.log('Down migration not applicable - duplicates cannot be restored.');
+    console.log(
+      'Down migration not applicable - duplicates cannot be restored.',
+    );
   },
 };

backend/src/db/migrations/20260331063424-cleanup-invalid-element-type-defaults.js

@@ -63,9 +63,7 @@ module.exports = {
       },
     );
 
-    console.log(
+    console.log(`Deleted ${idsToDelete.length} invalid element_type_defaults.`);
-      `Deleted ${idsToDelete.length} invalid element_type_defaults.`,
-    );
     console.log(
       `Deleted ${deletedProjectDefaults.length} invalid project_element_defaults.`,
     );

backend/src/db/migrations/20260403000001-add-background-video-settings.js

@@ -18,11 +18,15 @@ module.exports = {
       allowNull: false,
       defaultValue: true,
     });
-    await queryInterface.addColumn('tour_pages', 'background_video_start_time', {
+    await queryInterface.addColumn(
-      type: Sequelize.DECIMAL(10, 1),
+      'tour_pages',
-      allowNull: true,
+      'background_video_start_time',
-      defaultValue: null,
+      {
-    });
+        type: Sequelize.DECIMAL(10, 1),
+        allowNull: true,
+        defaultValue: null,
+      },
+    );
     await queryInterface.addColumn('tour_pages', 'background_video_end_time', {
       type: Sequelize.DECIMAL(10, 1),
       allowNull: true,
@@ -31,10 +35,19 @@ module.exports = {
   },
 
   async down(queryInterface, _Sequelize) {
-    await queryInterface.removeColumn('tour_pages', 'background_video_autoplay');
+    await queryInterface.removeColumn(
+      'tour_pages',
+      'background_video_autoplay',
+    );
     await queryInterface.removeColumn('tour_pages', 'background_video_loop');
     await queryInterface.removeColumn('tour_pages', 'background_video_muted');
-    await queryInterface.removeColumn('tour_pages', 'background_video_start_time');
+    await queryInterface.removeColumn(
-    await queryInterface.removeColumn('tour_pages', 'background_video_end_time');
+      'tour_pages',
+      'background_video_start_time',
+    );
+    await queryInterface.removeColumn(
+      'tour_pages',
+      'background_video_end_time',
+    );
   },
 };

backend/src/routes/file.js

@@ -27,11 +27,17 @@ router.post('/presign', jsonParser, async (req, res) => {
   const { urls } = req.body || {};
 
   if (!Array.isArray(urls) || urls.length === 0) {
-    return res.status(400).json(createErrorResponse('urls array required', 'MISSING_URLS'));
+    return res
+      .status(400)
+      .json(createErrorResponse('urls array required', 'MISSING_URLS'));
   }
 
   if (urls.length > 50) {
-    return res.status(400).json(createErrorResponse('Maximum 50 URLs per request', 'TOO_MANY_URLS'));
+    return res
+      .status(400)
+      .json(
+        createErrorResponse('Maximum 50 URLs per request', 'TOO_MANY_URLS'),
+      );
   }
 
   // Validate that all URLs are non-empty strings
@@ -39,24 +45,43 @@ router.post('/presign', jsonParser, async (req, res) => {
     (url) => typeof url !== 'string' || !url.trim(),
   );
   if (invalidUrls.length > 0) {
-    return res.status(400).json(createErrorResponse('All URLs must be non-empty strings', 'INVALID_URL_FORMAT'));
+    return res
+      .status(400)
+      .json(
+        createErrorResponse(
+          'All URLs must be non-empty strings',
+          'INVALID_URL_FORMAT',
+        ),
+      );
   }
 
   // Validate paths for security (no traversal, no protocols)
   const unsafeUrls = urls.filter((url) => !isValidPath(url));
   if (unsafeUrls.length > 0) {
     log.warn({ unsafeUrls }, 'Presign request with invalid paths rejected');
-    return res.status(400).json(createErrorResponse('Invalid file paths detected', 'INVALID_PATH', {
+    return res.status(400).json(
-      invalidPaths: unsafeUrls,
+      createErrorResponse('Invalid file paths detected', 'INVALID_PATH', {
-    }));
+        invalidPaths: unsafeUrls,
+      }),
+    );
   }
 
   try {
     const presignedUrls = await services.generatePresignedUrls(urls);
     res.json({ presignedUrls });
   } catch (error) {
-    log.error({ err: error, urlCount: urls.length }, 'Failed to generate presigned URLs');
+    log.error(
-    res.status(500).json(createErrorResponse('Failed to generate presigned URLs', 'PRESIGN_ERROR'));
+      { err: error, urlCount: urls.length },
+      'Failed to generate presigned URLs',
+    );
+    res
+      .status(500)
+      .json(
+        createErrorResponse(
+          'Failed to generate presigned URLs',
+          'PRESIGN_ERROR',
+        ),
+      );
   }
 });
 

backend/src/routes/users.js

@@ -13,7 +13,7 @@ const router = createEntityRouter('users', UsersService, UsersDBApi, {
 // Note: This needs to be added BEFORE the router is exported
 // The factory already registered this route, so we add middleware to sanitize
 const originalGetById = router.stack.find(
-  (layer) => layer.route?.path === '/:id' && layer.route?.methods?.get
+  (layer) => layer.route?.path === '/:id' && layer.route?.methods?.get,
 );
 
 if (originalGetById) {

backend/src/services/assets.js

@@ -93,12 +93,14 @@ class AssetsService extends BaseService {
 
     // Pre-generate reversed video for video assets (async, doesn't block response)
     if (assetType === 'video' && data.storage_key) {
-      AssetsService.preGenerateReversedVideo(asset, currentUser).catch((err) => {
+      AssetsService.preGenerateReversedVideo(asset, currentUser).catch(
-        logger.error(
+        (err) => {
-          { err, assetId: asset.id },
+          logger.error(
-          'Failed to pre-generate reversed video (non-blocking)',
+            { err, assetId: asset.id },
-        );
+            'Failed to pre-generate reversed video (non-blocking)',
-      });
+          );
+        },
+      );
     }
 
     return asset;
@@ -131,7 +133,9 @@ class AssetsService extends BaseService {
       // Check if reversed variant already exists (shouldn't happen on create, but safety check)
       const existingAsset = await AssetsDBApi.findBy({ id: asset.id });
       const variants = existingAsset?.asset_variants_asset || [];
-      const existingReversed = variants.find((v) => v.variant_type === 'reversed');
+      const existingReversed = variants.find(
+        (v) => v.variant_type === 'reversed',
+      );
 
       if (existingReversed) {
         log.debug('Reversed variant already exists');
@@ -172,7 +176,10 @@ class AssetsService extends BaseService {
       );
 
       log.info(
-        { reversedKey, sizeMb: (reversedBuffer.length / (1024 * 1024)).toFixed(2) },
+        {
+          reversedKey,
+          sizeMb: (reversedBuffer.length / (1024 * 1024)).toFixed(2),
+        },
         'Pre-generated reversed video successfully',
       );
 

backend/src/services/file.js

@@ -33,18 +33,25 @@ let gcloudHash = null;
 let uploadSessionManager = null;
 
 const getFileStorageProvider = () => {
-  const provider = (process.env.FILE_STORAGE_PROVIDER || '').trim().toLowerCase();
+  const provider = (process.env.FILE_STORAGE_PROVIDER || '')
+    .trim()
+    .toLowerCase();
   if (provider) return provider;
 
   const hasS3 = Boolean(
-    config.s3.bucket && config.s3.region &&
+    config.s3.bucket &&
-    config.s3.accessKeyId && config.s3.secretAccessKey
+    config.s3.region &&
+    config.s3.accessKeyId &&
+    config.s3.secretAccessKey,
   );
   if (hasS3) return 's3';
 
   const hasGCloud = Boolean(
-    process.env.GC_PROJECT_ID && process.env.GC_CLIENT_EMAIL &&
+    process.env.GC_PROJECT_ID &&
-    process.env.GC_PRIVATE_KEY && config.gcloud.bucket && config.gcloud.hash
+    process.env.GC_CLIENT_EMAIL &&
+    process.env.GC_PRIVATE_KEY &&
+    config.gcloud.bucket &&
+    config.gcloud.hash,
   );
   if (hasGCloud) return 'gcloud';
 
@@ -67,14 +74,17 @@ const getS3Provider = () => {
       keepAlive: config.s3.keepAlive,
     });
 
-    logger.info({
+    logger.info(
-      provider: 's3',
+      {
-      bucket: config.s3.bucket,
+        provider: 's3',
-      region: config.s3.region,
+        bucket: config.s3.bucket,
-      connectionTimeout: config.s3.connectionTimeout,
+        region: config.s3.region,
-      requestTimeout: config.s3.requestTimeout,
+        connectionTimeout: config.s3.connectionTimeout,
-      maxAttempts: config.s3.maxAttempts,
+        requestTimeout: config.s3.requestTimeout,
-    }, 'S3 storage provider initialized');
+        maxAttempts: config.s3.maxAttempts,
+      },
+      'S3 storage provider initialized',
+    );
   }
   return s3Provider;
 };
@@ -144,7 +154,11 @@ const getErrorMessage = (error, operation = 'process') => {
   const errorName = error?.name || '';
   const errorCode = error?.code || '';
 
-  if (errorName === 'NoSuchKey' || errorName === 'NotFound' || errorName === 'NoSuchBucket') {
+  if (
+    errorName === 'NoSuchKey' ||
+    errorName === 'NotFound' ||
+    errorName === 'NoSuchBucket'
+  ) {
     return 'File not found';
   }
   if (errorName === 'AccessDenied' || errorName === 'InvalidAccessKeyId') {
@@ -203,17 +217,25 @@ const uploadFile = async (folder, req, res) => {
     const processFile = require('../middlewares/upload');
     await processFile(req, res);
 
-    if (!req.file) return res.status(400).send(createErrorResponse('Please upload a file!', 'MISSING_FILE'));
+    if (!req.file)
+      return res
+        .status(400)
+        .send(createErrorResponse('Please upload a file!', 'MISSING_FILE'));
 
     const filename = req.body.filename;
-    if (!filename) return res.status(400).send(createErrorResponse('Missing filename', 'MISSING_FILENAME'));
+    if (!filename)
+      return res
+        .status(400)
+        .send(createErrorResponse('Missing filename', 'MISSING_FILENAME'));
 
     const privateUrl = `${folder}/${filename}`;
     let publicUrl = '';
 
     if (provider === 's3') {
       const s3 = getS3Provider();
-      const result = await s3.upload(privateUrl, req.file.buffer, { contentType: req.file.mimetype });
+      const result = await s3.upload(privateUrl, req.file.buffer, {
+        contentType: req.file.mimetype,
+      });
       publicUrl = result.url;
     } else if (provider === 'gcloud') {
       const { bucket, hash } = getGCloudBucket();
@@ -225,7 +247,9 @@ const uploadFile = async (folder, req, res) => {
         blobStream.on('finish', resolve);
         blobStream.end(req.file.buffer);
       });
-      publicUrl = format(`https://storage.googleapis.com/${bucket.name}/${blob.name}`);
+      publicUrl = format(
+        `https://storage.googleapis.com/${bucket.name}/${blob.name}`,
+      );
     } else {
       const local = getLocalProvider();
       await local.upload(privateUrl, req.file.buffer);
@@ -240,7 +264,14 @@ const uploadFile = async (folder, req, res) => {
     });
   } catch (error) {
     log.error({ err: error, provider }, 'Failed to upload file');
-    return res.status(500).send(createErrorResponse(`Could not upload the file. ${error.message || error}`, 'UPLOAD_ERROR'));
+    return res
+      .status(500)
+      .send(
+        createErrorResponse(
+          `Could not upload the file. ${error.message || error}`,
+          'UPLOAD_ERROR',
+        ),
+      );
   }
 };
 
@@ -249,12 +280,22 @@ const downloadFile = async (req, res) => {
   const privateUrl = req.query.privateUrl;
   const log = req.log || logger;
 
-  if (!privateUrl) return res.status(400).send(createErrorResponse('Missing privateUrl parameter', 'MISSING_PARAMETER'));
+  if (!privateUrl)
+    return res
+      .status(400)
+      .send(
+        createErrorResponse(
+          'Missing privateUrl parameter',
+          'MISSING_PARAMETER',
+        ),
+      );
 
   // Validate path
   if (!isValidPath(privateUrl)) {
     log.warn({ privateUrl }, 'Invalid file path requested');
-    return res.status(400).send(createErrorResponse('Invalid file path', 'INVALID_PATH'));
+    return res
+      .status(400)
+      .send(createErrorResponse('Invalid file path', 'INVALID_PATH'));
   }
 
   res.setHeader('Cross-Origin-Resource-Policy', 'cross-origin');
@@ -279,7 +320,8 @@ const downloadFile = async (req, res) => {
       const result = await s3.download(privateUrl, { signal });
 
       if (result.contentType) res.setHeader('Content-Type', result.contentType);
-      if (result.contentLength) res.setHeader('Content-Length', result.contentLength);
+      if (result.contentLength)
+        res.setHeader('Content-Length', result.contentLength);
 
       if (typeof result.body.pipe === 'function') {
         result.body.pipe(res);
@@ -290,7 +332,10 @@ const downloadFile = async (req, res) => {
         res.send(result.body);
       }
 
-      log.debug({ provider, privateUrl, duration: Date.now() - startTime }, 'File downloaded');
+      log.debug(
+        { provider, privateUrl, duration: Date.now() - startTime },
+        'File downloaded',
+      );
     } else if (provider === 'gcloud') {
       const { bucket, hash } = getGCloudBucket();
       const file = bucket.file(`${hash}/${privateUrl}`);
@@ -298,7 +343,9 @@ const downloadFile = async (req, res) => {
       if (exists) {
         file.createReadStream().pipe(res);
       } else {
-        res.status(404).send(createErrorResponse('File not found', 'NOT_FOUND'));
+        res
+          .status(404)
+          .send(createErrorResponse('File not found', 'NOT_FOUND'));
       }
     } else {
       res.download(path.join(config.uploadDir, privateUrl));
@@ -316,17 +363,24 @@ const downloadFile = async (req, res) => {
     const statusCode = provider === 's3' ? getS3ErrorStatusCode(error) : 500;
     const errorMessage = getErrorMessage(error, 'download');
 
-    log.error({
+    log.error(
-      err: error,
+      {
-      provider,
+        err: error,
-      privateUrl,
+        provider,
-      statusCode,
+        privateUrl,
-      errorName: error?.name,
+        statusCode,
-      errorCode: error?.code,
+        errorName: error?.name,
-    }, 'Failed to download file');
+        errorCode: error?.code,
+      },
+      'Failed to download file',
+    );
 
     if (!res.headersSent) {
-      return res.status(statusCode).send(createErrorResponse(errorMessage, error?.name || 'DOWNLOAD_ERROR'));
+      return res
+        .status(statusCode)
+        .send(
+          createErrorResponse(errorMessage, error?.name || 'DOWNLOAD_ERROR'),
+        );
     }
   }
 };
@@ -339,7 +393,8 @@ const downloadFile = async (req, res) => {
  * @returns {Promise<{ success: boolean, error?: Error }>}
  */
 const deleteFile = async (privateUrl, options = {}) => {
-  if (!privateUrl) return { success: false, error: new Error('Missing privateUrl') };
+  if (!privateUrl)
+    return { success: false, error: new Error('Missing privateUrl') };
 
   const { throwOnError = false } = options;
   const provider = getFileStorageProvider();
@@ -435,11 +490,15 @@ const uploadBuffer = async (privateUrl, buffer, options = {}) => {
       blobStream.on('finish', resolve);
       blobStream.end(buffer);
     });
-    return { url: `https://storage.googleapis.com/${bucket.name}/${blob.name}` };
+    return {
+      url: `https://storage.googleapis.com/${bucket.name}/${blob.name}`,
+    };
   } else {
     const local = getLocalProvider();
     await local.upload(privateUrl, buffer);
-    return { url: `/api/file/download?privateUrl=${encodeURIComponent(privateUrl)}` };
+    return {
+      url: `/api/file/download?privateUrl=${encodeURIComponent(privateUrl)}`,
+    };
   }
 };
 
@@ -448,13 +507,15 @@ const uploadBuffer = async (privateUrl, buffer, options = {}) => {
 // ============================================================================
 
 const sanitizeFolder = (folder) => {
-  const value = String(folder || '').trim().replace(/^\/+|\/+$/g, '');
+  const value = String(folder || '')
-  return (!value || value.includes('..')) ? null : value;
+    .trim()
+    .replace(/^\/+|\/+$/g, '');
+  return !value || value.includes('..') ? null : value;
 };
 
 const sanitizeFilename = (filename) => {
   const value = path.basename(String(filename || '').trim());
-  return (!value || value === '.' || value === '..') ? null : value;
+  return !value || value === '.' || value === '..' ? null : value;
 };
 
 const initUploadSession = async (req, res) => {
@@ -472,9 +533,20 @@ const initUploadSession = async (req, res) => {
     const size = Number(req.body?.size);
     const contentType = String(req.body?.contentType || '').trim();
 
-    if (!folder || !filename) return res.status(400).send(createErrorResponse('Invalid folder or filename', 'INVALID_INPUT'));
+    if (!folder || !filename)
-    if (!Number.isInteger(totalChunks) || totalChunks <= 0) return res.status(400).send(createErrorResponse('Invalid totalChunks', 'INVALID_INPUT'));
+      return res
-    if (!Number.isFinite(size) || size < 0) return res.status(400).send(createErrorResponse('Invalid file size', 'INVALID_INPUT'));
+        .status(400)
+        .send(
+          createErrorResponse('Invalid folder or filename', 'INVALID_INPUT'),
+        );
+    if (!Number.isInteger(totalChunks) || totalChunks <= 0)
+      return res
+        .status(400)
+        .send(createErrorResponse('Invalid totalChunks', 'INVALID_INPUT'));
+    if (!Number.isFinite(size) || size < 0)
+      return res
+        .status(400)
+        .send(createErrorResponse('Invalid file size', 'INVALID_INPUT'));
 
     const sessionId = sessionManager.createSession({
       userId: req.currentUser.id,
@@ -485,7 +557,10 @@ const initUploadSession = async (req, res) => {
       contentType,
     });
 
-    log.info({ sessionId, folder, filename, totalChunks, size }, 'Upload session initialized');
+    log.info(
+      { sessionId, folder, filename, totalChunks, size },
+      'Upload session initialized',
+    );
 
     return res.status(200).send({
       sessionId,
@@ -494,7 +569,14 @@ const initUploadSession = async (req, res) => {
     });
   } catch (error) {
     log.error({ err: error }, 'Failed to initialize upload session');
-    return res.status(500).send(createErrorResponse('Failed to initialize upload session', 'SESSION_INIT_ERROR'));
+    return res
+      .status(500)
+      .send(
+        createErrorResponse(
+          'Failed to initialize upload session',
+          'SESSION_INIT_ERROR',
+        ),
+      );
   }
 };
 
@@ -506,7 +588,12 @@ const getUploadSession = async (req, res) => {
     const sessionManager = getUploadSessionManager();
     const session = sessionManager.readMeta(sessionId);
 
-    if (!session) return res.status(404).send(createErrorResponse('Upload session not found', 'SESSION_NOT_FOUND'));
+    if (!session)
+      return res
+        .status(404)
+        .send(
+          createErrorResponse('Upload session not found', 'SESSION_NOT_FOUND'),
+        );
     if (session.userId !== req.currentUser.id) return res.sendStatus(403);
 
     return res.status(200).send({
@@ -518,7 +605,14 @@ const getUploadSession = async (req, res) => {
   } catch (error) {
     const log = req.log || logger;
     log.error({ err: error }, 'Failed to get upload session');
-    return res.status(500).send(createErrorResponse('Failed to get upload session', 'SESSION_GET_ERROR'));
+    return res
+      .status(500)
+      .send(
+        createErrorResponse(
+          'Failed to get upload session',
+          'SESSION_GET_ERROR',
+        ),
+      );
   }
 };
 
@@ -532,15 +626,27 @@ const uploadChunk = async (req, res) => {
     const chunkIndex = Number(req.params.chunkIndex);
 
     if (!Number.isInteger(chunkIndex) || chunkIndex < 0) {
-      return res.status(400).send(createErrorResponse('Invalid chunk index', 'INVALID_INPUT'));
+      return res
+        .status(400)
+        .send(createErrorResponse('Invalid chunk index', 'INVALID_INPUT'));
     }
 
     const sessionManager = getUploadSessionManager();
     const session = sessionManager.readMeta(sessionId);
 
-    if (!session) return res.status(404).send(createErrorResponse('Upload session not found', 'SESSION_NOT_FOUND'));
+    if (!session)
+      return res
+        .status(404)
+        .send(
+          createErrorResponse('Upload session not found', 'SESSION_NOT_FOUND'),
+        );
     if (session.userId !== req.currentUser.id) return res.sendStatus(403);
-    if (chunkIndex >= session.totalChunks) return res.status(400).send(createErrorResponse('Chunk index is out of range', 'INVALID_INPUT'));
+    if (chunkIndex >= session.totalChunks)
+      return res
+        .status(400)
+        .send(
+          createErrorResponse('Chunk index is out of range', 'INVALID_INPUT'),
+        );
 
     // Collect chunk data
     const chunks = [];
@@ -558,7 +664,11 @@ const uploadChunk = async (req, res) => {
     });
   } catch (error) {
     log.error({ err: error }, 'Failed to upload chunk');
-    return res.status(500).send(createErrorResponse('Failed to upload chunk', 'CHUNK_UPLOAD_ERROR'));
+    return res
+      .status(500)
+      .send(
+        createErrorResponse('Failed to upload chunk', 'CHUNK_UPLOAD_ERROR'),
+      );
   }
 };
 
@@ -572,18 +682,32 @@ const finalizeUploadSession = async (req, res) => {
     const sessionManager = getUploadSessionManager();
     const session = sessionManager.readMeta(sessionId);
 
-    if (!session) return res.status(404).send(createErrorResponse('Upload session not found', 'SESSION_NOT_FOUND'));
+    if (!session)
+      return res
+        .status(404)
+        .send(
+          createErrorResponse('Upload session not found', 'SESSION_NOT_FOUND'),
+        );
     if (session.userId !== req.currentUser.id) return res.sendStatus(403);
 
     // Verify all chunks exist
     for (let i = 0; i < session.totalChunks; i++) {
       if (!sessionManager.chunkExists(sessionId, i)) {
-        return res.status(400).send(createErrorResponse(`Missing chunk ${i}`, 'MISSING_CHUNK', { missingChunk: i }));
+        return res
+          .status(400)
+          .send(
+            createErrorResponse(`Missing chunk ${i}`, 'MISSING_CHUNK', {
+              missingChunk: i,
+            }),
+          );
       }
     }
 
     // Assemble file to temp location
-    const assembledPath = path.join(config.uploadDir, `assembled_${sessionId}_${Date.now()}`);
+    const assembledPath = path.join(
+      config.uploadDir,
+      `assembled_${sessionId}_${Date.now()}`,
+    );
     await sessionManager.assembleChunks(sessionId, assembledPath);
 
     const privateUrl = `${session.folder}/${session.filename}`;
@@ -594,13 +718,20 @@ const finalizeUploadSession = async (req, res) => {
       if (provider === 's3') {
         const s3 = getS3Provider();
         const data = fs.readFileSync(assembledPath);
-        const result = await s3.upload(privateUrl, data, { contentType: session.contentType });
+        const result = await s3.upload(privateUrl, data, {
+          contentType: session.contentType,
+        });
         publicUrl = result.url;
       } else if (provider === 'gcloud') {
         const { bucket, hash } = getGCloudBucket();
         const blob = bucket.file(`${hash}/${privateUrl}`);
-        await pipeline(fs.createReadStream(assembledPath), blob.createWriteStream({ resumable: false }));
+        await pipeline(
-        publicUrl = format(`https://storage.googleapis.com/${bucket.name}/${blob.name}`);
+          fs.createReadStream(assembledPath),
+          blob.createWriteStream({ resumable: false }),
+        );
+        publicUrl = format(
+          `https://storage.googleapis.com/${bucket.name}/${blob.name}`,
+        );
       } else {
         const local = getLocalProvider();
         const data = fs.readFileSync(assembledPath);
@@ -624,7 +755,14 @@ const finalizeUploadSession = async (req, res) => {
     });
   } catch (error) {
     log.error({ err: error }, 'Failed to finalize upload session');
-    return res.status(500).send(createErrorResponse('Failed to finalize upload session', 'SESSION_FINALIZE_ERROR'));
+    return res
+      .status(500)
+      .send(
+        createErrorResponse(
+          'Failed to finalize upload session',
+          'SESSION_FINALIZE_ERROR',
+        ),
+      );
   }
 };
 
@@ -651,7 +789,7 @@ const generatePresignedUrls = async (urls) => {
   await Promise.all(
     urls.map(async (url) => {
       presignedUrls[url] = await s3.getSignedUrl(url, expirySeconds);
-    })
+    }),
   );
 
   return presignedUrls;

backend/src/services/file/UploadSessionManager.js

@@ -76,7 +76,10 @@ class UploadSessionManager {
    * Get chunk file path
    */
   getChunkPath(sessionId, chunkIndex) {
-    return path.join(this.getChunksDir(sessionId), `${String(chunkIndex)}.part`);
+    return path.join(
+      this.getChunksDir(sessionId),
+      `${String(chunkIndex)}.part`,
+    );
   }
 
   /**
@@ -238,7 +241,9 @@ class UploadSessionManager {
           return;
         }
 
-        const updatedAt = new Date(meta.updatedAt || meta.createdAt || 0).getTime();
+        const updatedAt = new Date(
+          meta.updatedAt || meta.createdAt || 0,
+        ).getTime();
         if (!updatedAt || now - updatedAt > this.ttlMs) {
           this.removeSession(sessionId);
         }

backend/src/services/tour_pages.js

@@ -2,11 +2,7 @@
  * Tour Pages Service
  *
  * Extends the factory service with reversed video generation for back navigation transitions.
- *
+ * Reversed videos are always generated for forward navigation elements to support back navigation.
- * Supports two back navigation modes:
- * 1. target_page: Back button has its own transitionVideoUrl - reversed video generated for it
- * 2. history: Back button uses forward element from previous page - reversed video generated
- *    for forward elements when project has any history-mode back buttons
  */
 
 const Tour_pagesDBApi = require('../db/api/tour_pages');
@@ -17,8 +13,6 @@ const { downloadToBuffer, uploadBuffer } = require('./file');
 const videoProcessing = require('./videoProcessing');
 const { logger } = require('../utils/logger');
 
-// Cache for project history-mode status (cleared per request cycle)
-const projectHistoryModeCache = new Map();
 const projectRegenInProgress = new Set();
 const singleReverseGenerationInProgress = new Set();
 const reverseGenerationPromiseByStorageKey = new Map();
@@ -37,10 +31,11 @@ class TourPagesService extends BaseService {
    */
   static async create(data, currentUser) {
     // Process reversed videos and get updated ui_schema_json
-    const updatedData = await TourPagesService.processReversedVideosAndUpdateSchema(
+    const updatedData =
-      data,
+      await TourPagesService.processReversedVideosAndUpdateSchema(
-      currentUser,
+        data,
-    );
+        currentUser,
+      );
 
     return super.create(updatedData, currentUser);
   }
@@ -51,13 +46,15 @@ class TourPagesService extends BaseService {
   static async update(data, id, currentUser) {
     // Fetch existing page to get projectId (not included in update request body)
     const existingPage = await Tour_pagesDBApi.findBy({ id });
-    const projectId = existingPage?.projectId || data.projectId || data.project_id;
+    const projectId =
+      existingPage?.projectId || data.projectId || data.project_id;
 
     // Process reversed videos and get updated ui_schema_json
-    const updatedData = await TourPagesService.processReversedVideosAndUpdateSchema(
+    const updatedData =
-      { ...data, projectId, id },
+      await TourPagesService.processReversedVideosAndUpdateSchema(
-      currentUser,
+        { ...data, projectId, id },
-    );
+        currentUser,
+      );
 
     return super.update(updatedData, id, currentUser);
   }
@@ -88,94 +85,16 @@ class TourPagesService extends BaseService {
     return isForward && hasTarget && element.transitionVideoUrl;
   }
 
-  /**
-   * Check if any page in the project has a history-mode back button.
-   * Uses per-request caching to avoid repeated queries.
-   *
-   * @param {string} projectId - Project ID
-   * @returns {Promise<boolean>}
-   */
-  static async projectHasHistoryModeBackButton(projectId) {
-    if (!projectId) return false;
-
-    // Check cache first
-    if (projectHistoryModeCache.has(projectId)) {
-      return projectHistoryModeCache.get(projectId);
-    }
-
-    const { rows: pages } = await Tour_pagesDBApi.findAll(
-      { projectId },
-      { attributes: ['id', 'ui_schema_json'] },
-    );
-
-    logger.info(
-      { projectId, pageCount: pages.length },
-      'Checking project for history-mode back buttons',
-    );
-
-    for (const page of pages) {
-      const uiSchema =
-        typeof page.ui_schema_json === 'string'
-          ? JSON.parse(page.ui_schema_json || '{}')
-          : page.ui_schema_json || {};
-
-      if (!uiSchema.elements || !Array.isArray(uiSchema.elements)) continue;
-
-      for (const element of uiSchema.elements) {
-        const isBack = TourPagesService.isBackElement(element);
-
-        logger.debug(
-          {
-            pageId: page.id,
-            elementType: element.type,
-            navType: element.navType,
-            navBackMode: element.navBackMode,
-            isBack,
-          },
-          'Checking element for history mode',
-        );
-
-        if (isBack && element.navBackMode === 'history') {
-          logger.info(
-            { pageId: page.id, elementType: element.type },
-            'Found history-mode back button',
-          );
-          projectHistoryModeCache.set(projectId, true);
-          return true;
-        }
-      }
-    }
-
-    logger.info({ projectId }, 'No history-mode back buttons found in project');
-    projectHistoryModeCache.set(projectId, false);
-    return false;
-  }
-
-  /**
-   * Clear project cache (call at end of request or after project changes)
-   * @param {string} projectId - Project ID to clear, or undefined to clear all
-   */
-  static clearProjectCache(projectId) {
-    if (projectId) {
-      projectHistoryModeCache.delete(projectId);
-    } else {
-      projectHistoryModeCache.clear();
-    }
-  }
-
   /**
    * Process reversed videos and update ui_schema_json with reversed URLs.
    * Returns data with updated ui_schema_json.
    *
-   * Handles two cases:
+   * Generates reversed videos for all navigation elements with transitions.
-   * 1. Back navigation elements with transitionVideoUrl - always generate reversed
-   * 2. Forward navigation elements when project uses history-mode back navigation
    *
    * @param {Object} data - Page data with ui_schema_json
    * @param {Object} currentUser - Current user for permissions
    * @param {Object} options - Processing options
-   * @param {boolean} options._forceForwardReversed - Force processing forward elements
+   * @param {boolean} options._skipHistoryModeCheck - Skip initial regeneration check
-   * @param {boolean} options._skipHistoryModeCheck - Skip initial history mode check
    */
   static async processReversedVideosAndUpdateSchema(
     data,
@@ -202,43 +121,9 @@ class TourPagesService extends BaseService {
     // Get project ID
     const projectId = data.projectId || data.project_id || data.project;
 
-    // Check if this page being saved has a history-mode back button
-    // This is used to trigger regeneration of other pages' forward elements
-    let thisPageHasHistoryMode = false;
-
-    for (const element of uiSchema.elements) {
-      if (
-        TourPagesService.isBackElement(element) &&
-        element.navBackMode === 'history'
-      ) {
-        thisPageHasHistoryMode = true;
-        break;
-      }
-    }
-
-    // Check if project already has history-mode back buttons (from other pages)
-    // Skip this check if we're in regeneration mode to avoid recursion
-    let projectHasHistoryMode = options._forceForwardReversed || false;
-
-    if (!projectHasHistoryMode && projectId && !options._skipHistoryModeCheck) {
-      // Invalidate cache since we're about to save changes
-      TourPagesService.clearProjectCache(projectId);
-      projectHasHistoryMode =
-        await TourPagesService.projectHasHistoryModeBackButton(projectId);
-    }
-
-    // Combined check: process forward elements if project uses history mode OR this page enables it
-    const shouldProcessForward =
-      projectHasHistoryMode || thisPageHasHistoryMode;
-
     logger.info(
-      {
+      { projectId },
-        thisPageHasHistoryMode,
+      'Processing reversed videos for navigation elements',
-        projectHasHistoryMode,
-        shouldProcessForward,
-        projectId,
-      },
-      'History mode detection result',
     );
 
     let wasModified = false;
@@ -247,8 +132,8 @@ class TourPagesService extends BaseService {
       const isBack = TourPagesService.isBackElement(element);
       const isForward = TourPagesService.isForwardElementWithTarget(element);
 
-      // Determine if this element needs reversed video
+      // Always generate reversed videos for navigation elements with transitions
-      const needsReversed = isBack || (shouldProcessForward && isForward);
+      const needsReversed = isBack || isForward;
 
       logger.debug(
         {
@@ -260,7 +145,6 @@ class TourPagesService extends BaseService {
           hasTransitionVideo: Boolean(element.transitionVideoUrl),
           targetPageSlug: element.targetPageSlug,
           targetPageId: element.targetPageId,
-          shouldProcessForward,
         },
         'Evaluating element for reversed video',
       );
@@ -366,7 +250,12 @@ class TourPagesService extends BaseService {
    * @param {Object} task.currentUser
    * @param {string} [task.pageId]
    */
-  static enqueueSingleReverseGeneration({ projectId, storageKey, currentUser, pageId }) {
+  static enqueueSingleReverseGeneration({
+    projectId,
+    storageKey,
+    currentUser,
+    pageId,
+  }) {
     if (!projectId || !storageKey) return;
 
     const taskKey = `${projectId}:${storageKey}`;
@@ -392,7 +281,9 @@ class TourPagesService extends BaseService {
         );
 
         if (!reversedUrl) {
-          log.warn('Background reversed variant generation finished without result');
+          log.warn(
+            'Background reversed variant generation finished without result',
+          );
           return;
         }
 
@@ -435,7 +326,10 @@ class TourPagesService extends BaseService {
           excludePageId,
         );
       } catch (err) {
-        logger.error({ err, projectId }, 'Background project regeneration failed');
+        logger.error(
+          { err, projectId },
+          'Background project regeneration failed',
+        );
       } finally {
         projectRegenInProgress.delete(projectId);
       }
@@ -650,22 +544,26 @@ class TourPagesService extends BaseService {
 
         for (const element of uiSchema.elements) {
           // Process both forward elements AND back elements with their own transition
-          const isForward = TourPagesService.isForwardElementWithTarget(element);
+          const isForward =
+            TourPagesService.isForwardElementWithTarget(element);
           const isBackWithTransition =
             TourPagesService.isBackElement(element) &&
             element.transitionVideoUrl;
 
-          log.debug({
+          log.debug(
-            pageId: page.id,
+            {
-            elementType: element.type,
+              pageId: page.id,
-            navType: element.navType,
+              elementType: element.type,
-            isForward,
+              navType: element.navType,
-            isBackWithTransition,
+              isForward,
-            hasTransitionVideo: Boolean(element.transitionVideoUrl),
+              isBackWithTransition,
-            hasReverseVideo: Boolean(element.reverseVideoUrl),
+              hasTransitionVideo: Boolean(element.transitionVideoUrl),
-            targetPageSlug: element.targetPageSlug,
+              hasReverseVideo: Boolean(element.reverseVideoUrl),
-            targetPageId: element.targetPageId,
+              targetPageSlug: element.targetPageSlug,
-          }, 'Checking element in regeneration');
+              targetPageId: element.targetPageId,
+            },
+            'Checking element in regeneration',
+          );
 
           // Skip if neither forward nor back-with-transition
           if (!isForward && !isBackWithTransition) {

backend/src/services/users.js

@@ -6,7 +6,9 @@ const config = require('../config');
 const AuthService = require('./auth');
 
 // Generate base service from factory
-const BaseUsersService = createEntityService(UsersDBApi, { entityName: 'Users' });
+const BaseUsersService = createEntityService(UsersDBApi, {
+  entityName: 'Users',
+});
 
 /**
  * Users service with email invitation functionality

backend/src/services/videoProcessing.js

@@ -33,13 +33,20 @@ async function reverseVideo(inputBuffer, filename) {
     await new Promise((resolve, reject) => {
       ffmpeg(inputPath)
         .outputOptions([
-          '-vf', 'reverse',
+          '-vf',
-          '-af', 'areverse',
+          'reverse',
-          '-c:v', 'libx264',
+          '-af',
-          '-preset', 'fast',
+          'areverse',
-          '-crf', '23',
+          '-c:v',
-          '-c:a', 'aac',
+          'libx264',
-          '-movflags', '+faststart',
+          '-preset',
+          'fast',
+          '-crf',
+          '23',
+          '-c:a',
+          'aac',
+          '-movflags',
+          '+faststart',
         ])
         .output(outputPath)
         .on('start', (cmd) => logger.debug({ cmd }, 'FFmpeg command'))

frontend/src/components/Constructor/ElementEditorPanel.tsx

@@ -322,7 +322,6 @@ export function ElementEditorPanel({
                         selectedElement.transitionReverseMode || 'auto_reverse'
                       }
                       reverseVideoUrl={selectedElement.reverseVideoUrl || ''}
-                      navBackMode={selectedElement.navBackMode}
                       allowedNavigationTypes={allowedNavigationTypes}
                       iconAssetOptions={assetOptions.icon}
                       transitionVideoOptions={assetOptions.transitionVideo}

frontend/src/components/ElementSettings/NavigationSettingsSectionCompact.tsx

@@ -31,7 +31,6 @@ interface NavigationSettingsSectionCompactProps {
   transitionVideoUrl: string;
   transitionReverseMode: 'auto_reverse' | 'separate_video';
   reverseVideoUrl: string;
-  navBackMode?: 'target_page' | 'history';
   allowedNavigationTypes: NavigationElementType[];
   iconAssetOptions: AssetOption[];
   transitionVideoOptions: AssetOption[];
@@ -68,7 +67,6 @@ const NavigationSettingsSectionCompact: React.FC<
   transitionVideoUrl,
   transitionReverseMode,
   reverseVideoUrl,
-  navBackMode,
   allowedNavigationTypes,
   iconAssetOptions,
   transitionVideoOptions,
@@ -186,31 +184,16 @@ const NavigationSettingsSectionCompact: React.FC<
         )}
       </div>
 
-      {/* Back Navigation Mode - only shown for back buttons */}
+      {/* Back navigation info text */}
       {currentKind === 'back' && (
-        <div>
+        <p className='text-[11px] italic text-gray-500'>
-          <label className='mb-1 block text-[11px] font-semibold text-gray-600'>
+          Back button returns to the previous page using the original forward
-            Back Navigation Mode
+          transition in reverse.
-          </label>
+        </p>
-          <select
-            className='w-full rounded border border-gray-300 px-2 py-1 text-xs'
-            value={navBackMode || 'target_page'}
-            onChange={(e) => onChange('navBackMode', e.target.value)}
-          >
-            <option value='target_page'>Fixed target page</option>
-            <option value='history'>Previous page (browser-like)</option>
-          </select>
-          {navBackMode === 'history' && (
-            <p className='mt-1 text-[11px] text-gray-500'>
-              Returns to the page user came from, using the original forward
-              transition in reverse.
-            </p>
-          )}
-        </div>
       )}
 
-      {/* Only show target page and transition settings for forward buttons OR back buttons with target_page mode */}
+      {/* Only show target page and transition settings for forward buttons */}
-      {(currentKind === 'forward' || navBackMode !== 'history') && (
+      {currentKind === 'forward' && (
         <>
           <div>
             <label className='mb-1 block text-[11px] font-semibold text-gray-600'>

frontend/src/components/RuntimePresentation.tsx

@@ -46,6 +46,7 @@ import { logger } from '../lib/logger';
 import {
   resolveNavigationTarget,
   isTransitionBlocking,
+  isBackNavigation,
 } from '../lib/navigationHelpers';
 import type { TransitionPhase } from '../types/presentation';
 import type { CanvasElement } from '../types/constructor';
@@ -396,7 +397,7 @@ export default function RuntimePresentation({
         resolvedTargetPageId: navTarget?.pageId,
         transitionVideoUrl: element.transitionVideoUrl,
         hasTransition: Boolean(element.transitionVideoUrl),
-        navBackMode: element.navBackMode,
+        isBack: isBackNavigation(element),
         previousPageId: navContext.previousPageId,
       });
 

frontend/src/lib/elementDefaults.ts

@@ -110,7 +110,6 @@ export const TYPE_SPECIFIC_DEFAULTS: Partial<
     navDisabled: false,
     iconUrl: '',
     transitionReverseMode: 'auto_reverse',
-    navBackMode: 'target_page',
   },
   tooltip: {
     iconUrl: '',
@@ -490,7 +489,6 @@ export const buildElementSettings = (
       element.transitionReverseMode,
     );
     addIfNotEmpty(settings, 'reverseVideoUrl', element.reverseVideoUrl);
-    addIfNotEmpty(settings, 'navBackMode', element.navBackMode);
   }
 
   // Tooltip type settings

frontend/src/lib/navigationHelpers.ts

@@ -121,7 +121,7 @@ export const resolveHistoryBackTarget = (
 /**
  * Resolve target page from element navigation properties.
  * Supports both targetPageSlug (new) and targetPageId (legacy).
- * Also supports history-based back navigation when navBackMode='history'.
+ * Back navigation always uses history mode - returns to previous page.
  *
  * @param element - Element with navigation properties
  * @param pages - Available pages to search
@@ -133,8 +133,8 @@ export const resolveNavigationTarget = (
   pages: RuntimePage[],
   context?: NavigationContext,
 ): NavigationTarget | null => {
-  // Handle history-based back navigation
+  // Back navigation ALWAYS uses history mode
-  if (isBackNavigation(element) && element.navBackMode === 'history') {
+  if (isBackNavigation(element)) {
     return resolveHistoryBackTarget(
       pages,
       context?.currentPageSlug || '',
@@ -142,7 +142,7 @@ export const resolveNavigationTarget = (
     );
   }
 
-  // Standard target_page mode logic
+  // Forward navigation: resolve target page
   const targetPageSlug = element.targetPageSlug;
   const legacyTargetPageId = element.targetPageId;
 
@@ -158,15 +158,13 @@ export const resolveNavigationTarget = (
     return null;
   }
 
-  const isBack = isBackNavigation(element);
-
   return {
     page: targetPage,
     pageId: targetPage.id,
     transitionVideoUrl: element.transitionVideoUrl,
     transitionReverseMode: element.transitionReverseMode,
     reverseVideoUrl: element.reverseVideoUrl,
-    isBack,
+    isBack: false,
   };
 };
 

frontend/src/pages/constructor.tsx

@@ -33,6 +33,7 @@ import {
   resolveNavigationTarget,
   hasPlayableTransition,
   getNavigationDirection,
+  isBackNavigation,
 } from '../lib/navigationHelpers';
 import {
   mergeElementWithDefaults,
@@ -1034,8 +1035,8 @@ const ConstructorPage = ({ mode = 'constructor' }: ConstructorPageProps) => {
         const navTarget = resolveNavigationTarget(element, pages, navContext);
 
         if (!navTarget) {
-          // History mode back buttons need navigation history
+          // Back buttons always use history, forward buttons use target page
-          if (element.navBackMode === 'history') {
+          if (isBackNavigation(element)) {
             if (!navContext.previousPageId) {
               setErrorMessage(
                 'No previous page in history. Navigate to another page first.',
@@ -1053,17 +1054,16 @@ const ConstructorPage = ({ mode = 'constructor' }: ConstructorPageProps) => {
           return;
         }
 
-        // For history mode, use transition from navTarget (the forward element that brought us here)
+        // For back navigation, use transition from navTarget (the forward element that brought us here)
-        // For target_page mode, use the element's own transition settings
+        // For forward navigation, use the element's own transition settings
-        const transitionSource =
+        const transitionSource = isBackNavigation(element)
-          element.navBackMode === 'history'
+          ? {
-            ? {
+              type: element.type,
-                type: element.type,
+              transitionVideoUrl: navTarget.transitionVideoUrl,
-                transitionVideoUrl: navTarget.transitionVideoUrl,
+              transitionReverseMode: navTarget.transitionReverseMode,
-                transitionReverseMode: navTarget.transitionReverseMode,
+              reverseVideoUrl: navTarget.reverseVideoUrl,
-                reverseVideoUrl: navTarget.reverseVideoUrl,
+            }
-              }
+          : element;
-            : element;
 
         // Check if transition can be played using shared helper
         if (!hasPlayableTransition(transitionSource, direction)) {

frontend/src/types/constructor.ts

@@ -230,8 +230,6 @@ export interface CanvasElement extends BaseCanvasElement {
   reverseVideoUrl?: string;
   /** Storage key for the reversed transition video (pre-generated by backend) */
   transitionReversedStorageKey?: string;
-  /** Back navigation mode: 'target_page' navigates to fixed slug, 'history' uses page history */
-  navBackMode?: 'target_page' | 'history';
   transitionDurationSec?: number;
   // Gallery Carousel Settings
   galleryCarouselPrevIconUrl?: string;

frontend/src/types/presentation.ts

@@ -84,8 +84,6 @@ export interface NavigableElement {
   reverseVideoUrl?: string;
   navType?: 'forward' | 'back';
   navDisabled?: boolean;
-  /** Back navigation mode: 'target_page' navigates to fixed slug, 'history' uses page history */
-  navBackMode?: 'target_page' | 'history';
 }
 
 /**