**As a** user,

**I want to** preview a document without downloading or opening it,

**So that** I can quickly check if it’s the file I need.

**Description**

Users need the ability to quickly preview documents directly from the search results or document list, without having to download or open them in an external application. This feature should support common file types and provide a seamless, secure, and responsive experience. The preview should present the main content of the document and include basic navigation controls, ensuring users can efficiently determine if a file meets their needs. Access permissions must be enforced to maintain document security.

**Acceptance Criteria**


# 1. Preview Availability


**Given** a document is displayed in the search results or document list
**When** the user views the list
**Then** the system provides a "Preview" button or icon next to each document.


# 2. Supported File Types


**Given** the user clicks the "Preview" button
**When** the document is of a supported type (PDF, DOCX, XLSX, TXT, images)
**Then** the system opens a preview window or modal within the application.


# 3. Quick Access


**Given** the user clicks the "Preview" button
**When** the action is performed
**Then** the preview opens without requiring a full download or launching an external application.


# 4. Content Visibility


**Given** the preview window/modal is open
**When** the document is displayed
**Then** the system shows the main content (first few pages for documents, full image for images, etc.).


# 5. Navigation Controls


**Given** the preview window/modal is open
**When** the document supports navigation (e.g., multi-page PDFs)
**Then** the user has access to basic controls such as scrolling, paging, or zooming.


# 6. Performance


**Given** the user requests a preview for a document up to 10MB
**When** the preview is loading
**Then** the content loads within 2 seconds.


# 7. Security


**Given** the user does not have permission to view a document
**When** the user clicks the "Preview" button
**Then** the system prevents access and does not display the preview.


# 8. Error Handling


**Given** the user clicks the "Preview" button for an unsupported file type
**When** the action is performed
**Then** the system displays a friendly message, such as "Preview not available for this file type."