The SQLite Explorer has been successfully migrated from server-rendered JSX with HTMX to a React SPA with Hono backend, following Val Town best practices.

project-sqlite/
├── backend/
│   └── index.http.ts          # Main Hono server with API routes
├── frontend/
│   ├── components/
│   │   ├── Icons.tsx          # SVG icon components
│   │   ├── Table.tsx          # Query results table
│   │   ├── TablesList.tsx     # Database schema browser
│   │   ├── EditorSection.tsx  # SQL editor with CodeMirror
│   │   └── Separator.tsx      # Panel separators
│   ├── hooks/
│   │   ├── useCodeEditor.ts   # Editor state & SQL extraction
│   │   ├── useQueryExecution.ts # Query execution logic
│   │   ├── useTableSelection.ts # Table selection & persistence
│   │   └── useDownload.ts     # Download functionality
│   ├── App.tsx                # Main application component
│   ├── main.tsx               # React entry point
│   ├── index.html             # HTML template
│   ├── reset.css              # CSS reset
│   └── style.css              # Application styles
└── shared/
    ├── types.ts               # Shared TypeScript types
    ├── sqlHelpers.ts          # SQL parsing utilities
    └── exportHelpers.ts       # CSV/JSON export functions

• React 18.2.0 - UI framework
• @uiw/react-codemirror - SQL code editor
• @codemirror/lang-sql - SQL syntax highlighting
• TailwindCSS (twind) - Utility-first CSS via CDN
• Custom CSS - Layout and component styles

• Hono 4 - Lightweight web framework
• Val Town SQLite - Database (Turso/libSQL)
• Val Town utilities - File serving, auth, iframe handling

• sql-query-identifier - SQL statement parsing
• @json2csv/plainjs - CSV export

✅ All original features preserved:

• Database schema browser (tables & views)
• SQL editor with syntax highlighting
• Query execution with results display
• CSV and JSON export
• Query persistence per table (localStorage)
• Keyboard shortcuts (Cmd+Enter to run)
• Password authentication
• Error handling and display

✅ Architecture improvements:

• React state management (hooks-based)
• Clean separation of concerns
• Reusable components
• TypeScript types for type safety
• API-based data fetching
• Better code organization

The backend exposes the following REST API endpoints:

• GET /api/schema - Returns all tables and views
• POST /api/query - Executes SQL query, returns results
• GET /api/download/csv?query=... - Downloads results as CSV
• GET /api/download/json?query=... - Downloads results as JSON
• GET / - Serves React application
• GET /frontend/* - Serves frontend assets
• GET /shared/* - Serves shared utilities

1. Initial Load

   • Backend serves frontend/index.html
   • React app bootstraps via frontend/main.tsx
   • App component mounts and fetches database schema

2. Table Selection

   • User clicks table/view in sidebar
   • useTableSelection hook loads saved query from localStorage OR generates default SELECT * FROM table
   • Editor updates with query

3. Query Execution

   • User edits SQL in CodeMirror editor
   • Press Cmd+Enter or click Run button
   • useCodeEditor extracts statement at cursor position
   • useQueryExecution sends POST to /api/query
   • Results displayed in table below editor

4. Data Export

   • Click Download CSV/JSON button
   • useDownload hook triggers download from /api/download/*
   • Browser downloads file

The app uses React hooks for state management:

• App.tsx - Global state (schema, selected table)
• useCodeEditor - Editor content, cursor position, statement extraction
• useQueryExecution - Query results, errors, loading state
• useTableSelection - Table selection, localStorage sync
• useDownload - Download operations

• Application loads without errors
• Database schema loads and displays in sidebar
• Clicking a table loads default SELECT query
• SQL editor has syntax highlighting
• Code editor accepts text input
• Cmd+Enter executes query
• Run button executes query
• Query results display correctly in table
• SQL errors display in red text

• Download CSV button works
• Download JSON button works
• Buttons are disabled when editor is empty
• Buttons are enabled when editor has content
• Loading indicator shows during query execution
• Saved queries persist in localStorage
• Selecting a table loads saved query (if exists)

• Empty query handling
• Invalid SQL error messages
• Multi-statement SQL (executes statement at cursor)
• Large result sets display properly
• Views vs tables distinguished by icons

1. Ensure the project is in the Val Town recommended structure
2. The main entry point is backend/index.http.ts
3. The file should be set as type "http"
4. All authentication and iframe handling is already configured

For local development outside Val Town, you'll need to:

1. Replace Val Town-specific imports:

   • https://esm.town/v/std/sqlite → Use better-sqlite3 or Turso client
   • https://esm.town/v/std/utils → Implement file serving manually
   • Remove Val Town auth middleware (or implement custom auth)

2. Set up a dev server with Vite or similar

• ❌ HTMX (replaced with React state + fetch)
• ❌ Hyperscript (replaced with React event handlers)
• ❌ code-mirror web component (replaced with @uiw/react-codemirror)
• ❌ Server-side JSX rendering (now client-side React)

• ✅ React components and hooks
• ✅ TypeScript types
• ✅ REST API endpoints
• ✅ Client-side state management
• ✅ Better code organization
• ✅ DownloadSVG icon

• 🔄 Form submission → API calls via fetch
• 🔄 Hyperscript click handlers → React onClick
• 🔄 HTMX target swapping → React state updates
• 🔄 Server-rendered components → Client-rendered React
• 🔄 Inline scripts → React hooks

• Panel resizing is visual only (resize functionality not yet implemented)
  • Can use react-resizable-panels library if needed
• Authentication still uses Val Town-specific middleware
• File serving uses Val Town utilities

Potential improvements to consider:

• Query history panel (show recent queries)
• Saved queries UI (beyond localStorage)
• Query formatting button (using sql-formatter)
• Dark mode support
• Table schema viewer (show column names/types)
• Query execution time display
• Result pagination for large datasets
• Export options (limit rows, custom filename)
• Keyboard shortcut help panel
• Multiple tabs for queries

• Check browser console for errors
• Verify /frontend/index.html is being served
• Check that all imports resolve correctly

• Check backend console for errors
• Verify /api/query endpoint is accessible
• Check authentication is working

• Verify CodeMirror dependencies loaded from esm.sh
• Check React version is pinned to 18.2.0
• Look for import errors in browser console

• Check /api/download/* endpoints
• Verify query parameter is being passed
• Check browser download settings

• Val Town Docs
• React Docs
• Hono Docs
• CodeMirror 6 Docs

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Migration completed on: 2025-11-14 Framework: React 18 + Hono 4 Status: Ready for testing