# Background Email Processing User Stories & Acceptance Criteria

## User Stories

### Primary User Stories

#### 1. Automated Email Processing
**As a** user with configured email folders  
**I want** my emails to be automatically processed in the background  
**So that** I don't have to manually trigger email organization

**Acceptance Criteria:**
- [ ] Background task runs periodically to process emails for all users
- [ ] Only processes emails in folders with `organize_enabled = true`
- [ ] Processes emails according to all folder rules, moving emails as needed to the appropriate folder
- [ ] Respects priority field for folders
- [ ] Marks processed emails to avoid reprocessing
- [ ] Updates folder pending counts after processing
- [ ] Handles processing errors gracefully without stopping other folders
- [ ] Respects folder priority when processing (high priority first)

#### 2. Email Processing Status Tracking
**As a** user  
**I want** to see the status of email processing  
**So that** I can understand how many emails are pending organization

**Acceptance Criteria:**
- [ ] Pending email count is displayed for each folder
- [ ] Count updates in real-time after processing
- [ ] Processed email tracking prevents duplicate processing
- [ ] Email processing history is maintained

#### 3. Batch Email Processing
**As a** user with many emails  
**I want** emails to be processed in batches  
**So that** the system doesn't become unresponsive with large mailboxes

**Acceptance Criteria:**
- [ ] Emails are processed in configurable batch sizes
- [ ] Processing progress is tracked per batch
- [ ] Failed batches don't affect other batches
- [ ] System resources are managed efficiently during processing

#### 4. Error Handling & Recovery
**As a** user  
**I want** email processing errors to be handled gracefully  
**So that** temporary issues don't stop all email organization

**Acceptance Criteria:**
- [ ] Individual email processing failures don't stop folder processing
- [ ] Connection errors to IMAP servers are retried
- [ ] Transient errors are logged but don't halt processing
- [ ] Permanent failures are flagged for user attention
- [ ] Error notifications are sent for critical failures

#### 5. Processing Controls
**As a** user  
**I want** control over when emails are processed  
**So that** I can manage processing during preferred times

**Acceptance Criteria:**
- [ ] Users can enable/disable automatic processing per folder
- [ ] Users can trigger manual processing for specific folders
- [ ] Processing can be paused and resumed
- [ ] Processing schedule can be configured

### Secondary User Stories

#### 6. Performance Monitoring
**As a** system administrator  
**I want** to monitor email processing performance  
**So that** I can identify and resolve bottlenecks

**Acceptance Criteria:**
- [ ] Processing time metrics are collected
- [ ] Success/failure rates are tracked
- [ ] Resource usage during processing is monitored
- [ ] Performance alerts are sent for degraded performance

#### 7. Accessibility
**As a** user with disabilities  
**I want** email processing status to be accessible  
**So that** I can understand processing through assistive technologies

**Acceptance Criteria:**
- [ ] Processing status updates are announced by screen readers
- [ ] Visual indicators have proper contrast ratios
- [ ] Processing notifications are keyboard navigable
- [ ] Error messages are clear and descriptive

## Technical Requirements

### Backend Requirements
- [ ] Background task scheduler implementation
- [ ] IMAP connection management for processing
- [ ] Email processing logic with rule evaluation
- [ ] Processed email tracking system
- [ ] Error handling and logging mechanisms
- [ ] Performance monitoring and metrics collection

### Frontend Requirements
- [ ] Pending email count display
- [ ] Processing status indicators
- [ ] Manual processing controls
- [ ] Error notification UI
- [ ] Real-time updates for processing status

### Integration Requirements
- [ ] Integration with IMAP service for email access
- [ ] Integration with folder management system
- [ ] Integration with processed emails tracking
- [ ] API endpoints for manual processing controls

## Non-Functional Requirements

### Performance
- Process emails at a rate of at least 10 emails per second
- Background task execution interval configurable (default: 5 minutes)
- Memory usage capped to prevent system resource exhaustion
- Processing of large mailboxes (100k+ emails) completes without timeouts

### Reliability
- 99.5% uptime for background processing
- Automatic recovery from transient errors
- Graceful degradation when external services are unavailable
- Data consistency maintained during processing failures

### Scalability
- Support for 1000+ concurrent users
- Horizontal scaling of processing workers
- Efficient database queries for email tracking
- Load balancing of processing tasks across workers
