Feature Specification: Folder Organization

1. Overview & Vision

Folder Organization allows users to structure their digital workspace logically. It provides a recursive hierarchical system for grouping files, mirroring traditional file systems while adding cloud-native benefits like multi-tenant isolation and programmatic management.

2. Personas & Stakeholders

Persona	Goal
User	Create logical categories for documents (e.g., "Project X", "Invoices").
Manager	Organize team assets for better findability.
HR Admin	Maintain structured records for employees.

3. User Stories

• As a user, I want to create nested folders so I can organize my project assets by phase.
• As a user, I want to move files between folders so I can archive finished work.
• As an admin, I want to delete a folder and all its contents in one action.

4. Functional Requirements (FR)

• REQ-FO-001: Support for unlimited nested folder depth.
• REQ-FO-002: Unique folder names within the same parent directory (case-insensitive).
• REQ-FO-003: Rename a folder via a single PATCH request.
• REQ-FO-004: Recursive deletion of folders and all associated files and share links.

5. Non-Functional Requirements (NFR)

• Performance: Directory listing for 1000+ items < 300ms.
• Integrity: Orphaned files MUST NOT exist after folder deletion.

6. Business Logic & Rules

• Validation: Folder names cannot contain reserved system characters (e.g., /, \).
• Owner Inheritance: New folders inherit the organizationId of the creator.
• Rename Authorization: Non-admin users can only rename folders they created (created_by).

7. User Interface (UI/UX)

• Breadcrumb Navigation: Dynamic trail for quick upward navigation.
• Tree View: Left-rail expandable folder structure.
• Interactions: Drag-and-drop to move; Right-click context menus.

8. Information Architecture

• Integrated within the primary Drive Explorer.
• Path-based URL routing (e.g., /drive/folders/:id).

9. Data Model & Persistence

• Table: folders.
• Constraint: Self-referencing parentId with ON DELETE CASCADE (metadata only).

10. API & Service Layer

• GET /api/folders — list folders, filtered by parentId
• POST /api/folders — create folder
• PATCH /api/folders/:id — rename folder ({ name: string })
• DELETE /api/folders/:id — recursive delete

11. Integration Patterns

• Events: Moving a folder triggers a background job to update any external search indexes.

12. Security & Permissions

• RBAC: drive:write required to create/modify folders.
• Tenant Lock: API prevents fetching or modifying folders belonging to another orgId.

13. Error Handling & Resilience

• Recursive Cleanup: Service layer ensures S3 objects are deleted when SQL folders are removed.
• Conflict detection: Standard 409 Conflict for duplicate names.

14. Performance & Scalability

• Materialized paths (planned for v1.3) to optimize deep-tree queries.
• Pagination for large directory listings.

15. Globalization & i18n

• Support for multi-byte (Unicode) folder names.

16. Accessibility (a11y)

• Accessible tree components with keyboard navigation (Up/Down/Left/Right).
• Aria-labels for folder actions.

17. Observability & Analytics

• Tracking of "Directory Depth" to identify potential UX friction points.

18. Testing & Quality

• Recursive logic unit tests.
• E2E testing of the rename and recursive delete workflows.

19. Constraints & Assumptions

• Assumes SQL level triggers or application logic handle recursive S3 cleanup.

20. Future Enhancements

• Move folders to a different parent (change parentId).
• Bulk rename and bulk move operations.
• Shared Folders (cross-user permissions within an org).
• Color-coded folder icons.