# Changelog

All notable changes to the Trax Media Processing Platform will be documented in this file.

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [2.0.0] - 2024-12-30

### Added
- **V2 Schema Migration**: Complete database schema upgrade for v2 features
  - New `speaker_profiles` table for speaker diarization and identification
  - New `v2_processing_jobs` table for individual transcript processing
  - Enhanced `transcription_results` table with v2-specific columns
  - Backward compatibility layer for v1 clients
  - Comprehensive data migration utilities

- **Speaker Profile Management**:
  - Speaker profile creation and management
  - Voice characteristics storage in JSONB format
  - Speaker embedding support for identification
  - Sample count tracking for speaker profiles
  - User association for speaker profiles

- **V2 Processing Jobs**:
  - Individual transcript processing job tracking
  - Progress monitoring with percentage tracking
  - Job type support (enhancement, diarization, etc.)
  - Parameter storage in JSONB format
  - Error handling and result data storage

- **Enhanced Transcription Results**:
  - Pipeline version tracking (v1, v2, v3, v4)
  - Enhanced content storage for improved transcriptions
  - Speaker diarization content storage
  - Merged content from multiple sources
  - Domain-specific processing support
  - Accuracy estimation for v2 processing
  - Speaker count tracking
  - Quality warnings and processing metadata

- **Backward Compatibility Layer**:
  - V1 to V2 format conversion utilities
  - V2 to V1 format conversion for existing clients
  - Migration utilities for v1 transcripts
  - Feature detection and summary utilities
  - Automatic migration of existing data

- **Repository Layer**:
  - `SpeakerProfileRepository` with CRUD operations
  - `V2ProcessingJobRepository` with job management
  - Protocol-based design for easy swapping and testing
  - Comprehensive error handling and validation
  - Search and statistics capabilities

- **Data Migration Scripts**:
  - Bulk migration of existing transcript data
  - Specific transcript migration capabilities
  - Migration validation and rollback procedures
  - Comprehensive error handling and logging
  - Migration statistics and reporting

- **Alembic Migration**:
  - Complete schema migration script
  - Proper indexes and foreign key constraints
  - Downgrade path for rollback procedures
  - Data preservation during migration

### Changed
- **Database Schema**: Updated to support v2 features while maintaining backward compatibility
- **Transcription Results**: Enhanced with v2-specific columns (nullable for compatibility)
- **Repository Pattern**: Implemented protocol-based interfaces for better testing
- **Error Handling**: Improved error handling throughout the data layer
- **Performance**: Added indexes for v2-specific queries and operations

### Technical Details
- **Registry Pattern**: All models use the registry pattern to prevent SQLAlchemy errors
- **UTC Timestamps**: All timestamps use UTC timezone consistently
- **JSONB Support**: Extensive use of PostgreSQL JSONB for flexible data storage
- **Protocol Interfaces**: Service interfaces use typing.Protocol for easy swapping
- **Comprehensive Testing**: Full test suite with real database testing
- **Documentation**: Updated DB-SCHEMA.md and CHANGELOG.md with v2 details

### Migration Notes
- **Backward Compatible**: All v2 columns are nullable, allowing v1 clients to continue working
- **Automatic Migration**: Existing transcripts are automatically migrated to v2 format
- **Rollback Support**: Complete rollback procedures available if needed
- **Data Preservation**: All existing data is preserved during migration

### Testing & Validation
- **Schema Tests**: All 15 v2 schema migration tests pass successfully
- **Test Database**: Properly configured `trax_test` database for isolated testing
- **Foreign Key Testing**: Validated all foreign key relationships and constraints
- **Backward Compatibility**: Verified v1 data works correctly with v2 schema
- **Helper Methods**: Created reusable test helpers for complex data setup

### Lessons Learned
- **Test Database Setup**: Always create separate test database before running schema tests
- **Dependency Order**: When testing foreign key relationships, create parent records first
- **Schema Matching**: Ensure test expectations match actual database schema (column types, nullability)
- **Helper Functions**: Create reusable test helpers for complex data setup
- **Migration Testing**: Test both upgrade and downgrade paths for migrations

## [0.2.0] - 2024-12-30

### Added
- **Batch Processing System**: Comprehensive batch processing capabilities
  - Batch job creation and management
  - Task type support (transcribe, enhance, youtube, download, preprocess)
  - Priority-based task processing
  - Retry mechanism with configurable limits
  - Processing time and error tracking
  - Resource monitoring integration

- **Enhanced Task Management**:
  - Task data storage in JSONB format
  - Priority levels for task processing
  - Status tracking with state machine
  - Error message storage and retry logic
  - Result data storage for completed tasks

- **Resource Management**:
  - Worker count configuration
  - Memory limit monitoring
  - CPU usage tracking
  - Processing time measurement
  - Resource optimization

### Changed
- **Database Schema**: Added batch processing tables and enhanced existing tables
- **Task Processing**: Improved task handling with better error recovery
- **Performance**: Enhanced performance monitoring and optimization

## [0.1.1] - 2024-12-25

### Added
- **AI Enhancement Service**: Enhanced transcription capabilities
  - Enhanced content storage in transcripts table
  - Quality validation and accuracy tracking
  - Processing time measurement
  - Quality warnings and error handling
  - Caching support for enhancement results

### Changed
- **Transcription Quality**: Improved accuracy and quality metrics
- **Performance**: Enhanced processing time tracking
- **Error Handling**: Better error reporting and warnings

## [0.1.0] - 2024-12-19

### Added
- **Core Platform**: Initial release of Trax Media Processing Platform
  - YouTube video metadata extraction
  - Media file download and storage
  - Basic transcription with Whisper API
  - Audio processing metadata tracking
  - Export functionality (JSON and TXT formats)

- **Database Schema**: Complete initial database design
  - YouTube videos metadata storage
  - Media files download tracking
  - Transcription results storage
  - Audio processing metadata
  - Export history tracking

- **CLI Interface**: Command-line interface for platform operations
  - YouTube video processing
  - Media file management
  - Transcription operations
  - Export functionality
  - Progress tracking and status reporting

- **Core Services**:
  - YouTube service for metadata extraction
  - Media service for file management
  - Transcription service with Whisper integration
  - Export service for multiple formats
  - Audio processing service

### Technical Features
- **PostgreSQL Database**: Full PostgreSQL support with JSONB
- **SQLAlchemy ORM**: Modern SQLAlchemy 2.0+ with async support
- **Alembic Migrations**: Database schema versioning and migration
- **Registry Pattern**: Prevents SQLAlchemy "multiple classes" errors
- **Async/Await**: Full async support throughout the platform
- **Error Handling**: Comprehensive error handling and logging
- **Testing**: Full test suite with real database testing

### Performance Features
- **Download-First Architecture**: Always download media before processing
- **Audio Optimization**: Convert to 16kHz mono WAV for processing
- **Caching Strategy**: Multi-layer caching with different TTLs
- **Batch Processing**: Queue-based batch processing with progress tracking
- **Resource Management**: Memory and CPU limit enforcement

## [Unreleased]

### Planned Features
- **Version 2.1.0**: Advanced Speaker Features
  - Speaker clustering and identification
  - Voice fingerprinting
  - Speaker confidence scoring
  - Multi-language speaker support

- **Version 2.2.0**: Enhanced Processing
  - Real-time processing capabilities
  - Advanced quality metrics
  - Processing pipeline optimization
  - Performance monitoring

- **Version 3.0.0**: Enterprise Features
  - Multi-tenant support
  - Advanced analytics and reporting
  - API rate limiting and quotas
  - Enterprise integration features

### Technical Improvements
- **Performance Optimization**: Further performance improvements
- **Scalability**: Enhanced scalability for large-scale processing
- **Monitoring**: Advanced monitoring and alerting
- **Security**: Enhanced security features
- **Documentation**: Comprehensive API documentation

---

## Migration Guide

### Upgrading to v2.0.0

1. **Backup Database**: Create a complete backup before migration
2. **Run Alembic Migration**: Execute the v2 schema migration
3. **Run Data Migration**: Execute the data migration script
4. **Validate Migration**: Run validation to ensure data integrity
5. **Update Application**: Update application code to use v2 features

### Rollback Procedure

If issues arise during migration:

1. **Stop Application**: Stop all application instances
2. **Run Rollback Migration**: Execute the rollback migration script
3. **Verify Data**: Ensure all data is intact
4. **Restart Application**: Restart with v1 compatibility mode

### Compatibility Notes

- **V1 Clients**: Continue to work without modification
- **V2 Features**: Available for new implementations
- **Data Migration**: Automatic migration of existing data
- **API Compatibility**: Backward compatible API endpoints

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## Contributing

When contributing to this project, please:

1. Follow the existing code style and patterns
2. Add appropriate tests for new features
3. Update documentation for any schema changes
4. Follow the migration guidelines for database changes
5. Ensure backward compatibility when possible

## Support

For support and questions:

- Check the documentation in the `docs/` directory
- Review the database schema documentation
- Consult the migration guides
- Check the troubleshooting documentation
