Implement Offline Maps and Navigation

[HordRicJr]

Description

HordMaps needs robust offline functionality to provide navigation services even without internet connectivity, including downloadable maps and cached route data.

Tasks to Complete

Offline Map Tiles

• Implement tile downloading for specific regions
• Add map region selection UI for downloads
• Create efficient tile storage and indexing system
• Implement background tile downloading
• Add download progress tracking and management

Offline Navigation

• Cache route data for offline use
• Implement offline route calculation algorithms
• Add offline POI search functionality
• Create offline geocoding capabilities
• Support offline turn-by-turn navigation

Data Management

• Implement intelligent cache management
• Add storage usage monitoring and cleanup
• Create data compression for offline maps
• Add selective data download options
• Implement cache expiration and refresh strategies

User Interface

• Add offline maps management screen
• Create download region selection tool
• Show offline availability indicators
• Add storage usage visualization
• Implement offline mode toggle

Sync and Updates

• Add automatic map updates when online
• Implement differential updates for map data
• Create sync status indicators
• Add manual refresh options
• Handle data conflicts and versioning

Performance Optimization

• Optimize offline data access speed
• Implement efficient tile rendering from storage
• Add background processing for data management
• Optimize battery usage during offline operations
• Implement smart caching strategies

Error Handling

• Handle graceful degradation when data unavailable
• Add clear indicators for offline limitations
• Implement fallback mechanisms
• Create user-friendly error messages
• Add recovery options for corrupted data

Technical Requirements

• Use SQLite or similar for efficient data storage
• Implement proper database indexing for fast queries
• Follow platform storage guidelines and limitations
• Ensure data integrity and consistency
• Add proper error handling and recovery mechanisms

Hacktoberfest Notes

Great for developers interested in data management and offline-first applications! Perfect for contributors who want to work on complex caching and storage systems.

Resources

• Flutter SQLite
• Offline-First Development
• Map Tiles Standards

[yashraj4]

Apart from what's already there in offline_service.dart file, I would like to propose the following changes considering what all u have mentioned:

1. Data Storage: Migrating to SQLite

The current implementation stores map tiles as individual files. I suggest we move to an SQLite database so that we can query and delete cache data easily. Since the downloads are atomic, it also prevents data corruption if the process is interrupted.

Inside schema there will be two tables: offline_regions and map_tiles.

2. Offline Navigation

1. When a user generates a route online, we can save the route data (coordinates, turn-by-turn instructions, etc.) to the SQLite database.
2. We can download and store POI and geocoding data for the offline regions the user has saved.

3. Background Downloading

I suggest using a package like flutter_downloader or workmanager for this.

4. Optimization

1. We can implement a LRU policy to automatically clear out old, unused map tiles when the cache is full.
2. We can prompt users to update their offline maps after a certain amount of time has passed.
3. We can provide more informative error messages to the user if a download fails and offer a "retry" option.

Please let me know your thoughts on this and I request u to assign me this issue.

Thank you!