This directory contains the server-side code for the Flashcard Learning App.

• index.ts - Main Hono app setup, route mounting, and static file serving
• storage.ts - Blob storage utilities for user data persistence
• routes/ - API endpoint implementations

• Handles user login and initialization
• Creates new user data if doesn't exist

• CRUD operations for flashcard decks
• Cascade deletion of cards when deck is deleted

• CRUD operations for flashcards
• Validates deck existence before card creation

• Fetches due cards based on spaced repetition
• Processes card reviews and updates SM-2 parameters

• Retrieves user statistics
• Saves completed study sessions

• Exports user data as JSON
• Imports user data from JSON backup

All routes (except login) require X-Username header for user identification.

Hono's onError is configured to throw errors for full stack traces.

1. Load user data from blob storage
2. Perform in-memory operations
3. Save back to blob storage

1. Create new file in routes/
2. Export a Hono instance
3. Mount in index.ts with app.route()
4. Add X-Username header check if needed