TODO.md

TODO.md - Android Google Drive Sync Library

Track outstanding tasks, features, and improvements

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Phase 1: Project Setup

• Create Gradle project structure with library and sample modules
• Configure build.gradle.kts with required dependencies
• Set up Hilt dependency injection
• Configure detekt for code quality
• Create .gitignore with appropriate rules
• Set up GitHub Actions CI pipeline
• Configure library publishing (Maven)

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Phase 2: Core Infrastructure

Authentication Module (auth/)

• Implement GoogleAuthManager with Google Sign-In
• Handle OAuth2 token management and refresh
• Create AuthState sealed class for auth states
• Create AuthResult sealed class for auth operations
• Create AuthConfig data class for configuration
• Add sign-out and account switching support
• Write unit tests for auth flows (requires Android framework mocking)

Drive Operations Module (drive/)

• Implement DriveService wrapper for Drive API v3
• Create DriveFileOperations for CRUD operations
  • Upload file (create/update)
  • Download file
  • Delete file
  • List files with pagination
  • Get file metadata
• Implement DriveFolderManager for folder hierarchy
  • Create folder
  • Find folder by name/path
  • Ensure folder hierarchy exists
• Define DriveModels data classes (DriveFile, DriveFolder, DriveOperationResult, etc.)
• Write comprehensive tests

Local File Module (local/)

• Implement LocalFileManager for local file I/O
• Create FileHasher with MD5 and SHA256 support
• Implement FileFilter for include/exclude patterns
  • Glob pattern matching
  • Extension filtering
  • Size filtering
  • Hidden file handling
• Write tests for FileFilter
• Write tests for FileHasher

Resilience Module (resilience/)

• Implement RetryPolicy with exponential backoff
• Create NetworkMonitor for connectivity checking
• Implement SyncProgressManager for progress tracking
• Write tests for RetryPolicy

Dependency Injection (di/)

• Create GoogleSyncModule Hilt module
• Configure all singleton dependencies

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Phase 3: Sync Engine

Sync Core (sync/)

• Implement SyncManager as main orchestrator
• Create SyncEngine with core sync logic
  • Upload flow with checksum comparison
  • Download flow with checksum comparison
  • Full bidirectional sync
  • Delta sync (changes only)
• Implement SyncPolicy strategies
  • Upload-only mode
  • Download-only mode
  • Bidirectional mode
  • Mirror mode (exact replica)
• Create ConflictResolver with policies
  • LOCAL_WINS
  • REMOTE_WINS
  • NEWER_WINS
  • KEEP_BOTH
  • ASK_USER (callback)
  • SKIP
• Implement SyncState tracking
• Add progress reporting via Flow
• Write tests for ConflictResolver
• Write tests for SyncModels
• Write tests for SyncEngine (integration tests)

Cache Layer (cache/)

• Implement SyncCache for metadata caching
• Create manifest caching with disk persistence
• Define CacheConfig for invalidation rules
• Add cache persistence (JSON file-based)
• Write cache tests

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Phase 4: Resilience & Background Sync

Resilience Module (resilience/)

• Implement RetryPolicy with exponential backoff
• Create NetworkMonitor for connectivity checking
• Implement error recovery via retry policies
• Add operation queueing for offline support
• Handle rate limiting gracefully
• Write resilience tests

Worker Module (worker/)

• Implement SyncWorker for WorkManager
• Create SyncScheduler for periodic scheduling
• Define SyncScheduleConfig configuration
• Add one-time sync work support
• Implement sync notifications (optional)
• Write worker tests

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Phase 5: Public API

API Module (api/)

• Design and implement GoogleSyncClient class
• Create SyncClientConfigBuilder builder
• Define SyncResult sealed class hierarchy
• Implement progress observation via StateFlow
• Create SyncOptions for operation customization
• Add backup/restore API
  • Create ZIP backup
  • Restore from backup
  • List available backups
• Write API documentation (KDoc)
• Create integration tests

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Phase 6: Persistence (Optional)

Database Module (db/)

• Create SyncDatabase with Room
• Define SyncStateEntity for tracking
• Implement SyncStateDao with queries
• Add migration support
• Write database tests

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Phase 7: Sample App

• Create sample app module
• Implement sign-in screen
• Create sync status dashboard
• Add file browser with file management
• Implement manual sync trigger
• Add settings for sync configuration
• Show sync history/logs
• Test on multiple devices

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Phase 8: Documentation & Polish

Documentation

• Write comprehensive README.md
• Create INTEGRATION.md guide
• Document CONFIGURATION.md options
• Write TROUBLESHOOTING.md
• Add inline code examples
• Create API reference (KDoc)

Quality Assurance

• Achieve 80%+ test coverage
• Pass all detekt checks (with baseline for complex methods)
• Review and optimize performance
• Memory leak testing
• Large file handling tests
• Stress testing with many files

Release Preparation

• Version 1.0.0 feature freeze
• Final documentation review
• Create CHANGELOG.md
• Prepare Maven Central publishing
• Create GitHub release

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Future Enhancements (Post 1.0)

Features

• Support for Google Drive Shared Drives
• Selective folder sync (choose specific folders)
• Real-time sync with Drive push notifications
• Encryption at rest (encrypt files before upload)
• Multi-device safety with instance ID validation
• Sync metadata file for change detection
• Batch processing with rate limit avoidance
• Progress timeout monitoring
• Compression before upload
• Bandwidth throttling
• Sync pause/resume
• Sync queue with priority

Platform Support

• Kotlin Multiplatform (KMP) support
• Desktop (JVM) support
• iOS via KMP

Integrations

• Support for other cloud providers (OneDrive, Dropbox)
• SAF (Storage Access Framework) integration
• Content provider support

Performance

• Chunked upload for large files
• Parallel upload/download
• Resume interrupted transfers
• Smart batching of operations

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Known Issues

Track bugs and issues here

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Notes

• Reference vane-client-manager for proven patterns
• Reference vane-spark-notes for sync implementation details
• Prioritize reliability over features
• Test on real devices with real Drive accounts
• Consider quota limits and rate limiting

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Last Updated: 2026-01-13