# Implementation Summary

## Overview

Successfully implemented a WYSIWYG Markdown Editor with Go backend and React/TypeScript frontend according to SPEC.md.

## Backend Implementation (Go)

### Completed Milestones

**B1: CLI & Server Setup** ✅
- Cobra CLI with `--data-dir`, `--port`, `--host` flags
- HTTP server with basic routing
- Default values: data-dir=./data, port=8080, host=127.0.0.1

**B2: CRUD API** ✅
- REST endpoints for markdown files:
  - GET /api/{filename}.md - Read file
  - POST /api/{filename}.md - Create file
  - PUT /api/{filename}.md - Update file
  - DELETE /api/{filename}.md - Delete file
- JSON error responses (4xx/5xx)

**B3: File Storage** ✅
- Read/write .md files to disk
- Flat file structure in data directory

**B4: Logging** ✅
- Comprehensive logrus logging for all operations
- Info level logging with timestamps

**B5: Static Assets** ✅
- Serves frontend build files from frontend/dist
- Proper routing to serve index.html and assets

**B6: Backend Tests** ✅
- CRUD round-trip tests (create, read, update, delete)
- Static asset serving tests
- All tests passing

### Backend Structure

```
backend/
  cmd/backend/
    main.go          - Entry point with Cobra CLI
  internal/
    api/
      api.go         - API handler with CRUD operations
    logger/
      logger.go      - Logrus logger setup
    server/
      server.go      - HTTP server with routing
  tests/
    api_test.go     - Comprehensive tests
  go.mod
  go.sum
  Makefile
```

## Frontend Implementation (React + TypeScript + Tailwind)

### Completed Milestones

**F1: Project Setup** ✅
- React + TypeScript + Tailwind configured
- Vite as build tool
- ESLint and Prettier configured

**F2: File Management UI** ✅
- List markdown files
- Create new documents
- Open, save, delete files
- API integration with backend

**F3: Editor & Preview** ✅
- Markdown editor with live GFM preview
- React Markdown with remark-gfm plugin
- Side-by-side editor/preview layout

**F4: Theme System** ✅
- Dark, Light, and System themes
- Theme switcher dropdown
- Theme persistence via localStorage
- Dark mode CSS classes

**F5: Responsive Design** ✅
- Works at 320px (mobile) and 1920px (desktop)
- Tailwind responsive utilities
- Flexbox layout that adapts to screen size

**F6: Frontend Tests** ✅
- Core functionality tests
- Theme switching tests
- File management tests
- All tests passing

### Frontend Structure

```
frontend/
  src/
    App.tsx         - Main application component
    main.tsx        - React entry point
    index.css       - Global styles
    setupTests.ts   - Test setup
    App.test.tsx    - Component tests
  package.json
  vite.config.ts
  tailwind.config.js
  postcss.config.js
  tsconfig.json
  index.html
```

## Integration

**I1: End-to-end** ✅
- Full CRUD workflow tested
- Frontend to backend communication verified
- Static asset serving confirmed

## Testing

### Backend Tests
```bash
cd backend
make test
```
- Tests CRUD operations
- Tests static asset serving
- All tests passing

### Frontend Tests
```bash
cd frontend
npm test
```
- Tests component rendering
- Tests theme switching
- Tests file management
- All tests passing

## Build Process

### Backend Build
```bash
cd backend
make build
```
- Output: `bin/markdown-editor`

### Frontend Build
```bash
cd frontend
npm run build
```
- Output: `dist/` directory with optimized assets

## Running the Application

```bash
# Start the server
./backend/bin/markdown-editor

# Or with custom configuration
./backend/bin/markdown-editor --data-dir ./my-data --port 3000 --host 0.0.0.0

# Access at http://localhost:8080
```

## API Endpoints

- `GET /api/{filename}.md` - Get markdown file content
- `POST /api/{filename}.md` - Create a new markdown file
- `PUT /api/{filename}.md` - Update an existing markdown file
- `DELETE /api/{filename}.md` - Delete a markdown file

## Features Implemented

✅ CLI with Cobra (--data-dir, --port, --host)
✅ REST API for markdown files (CRUD)
✅ File storage on disk
✅ Logrus logging
✅ Static asset serving
✅ React + TypeScript + Tailwind frontend
✅ Markdown editor with live preview
✅ File management (list, create, open, save, delete)
✅ Theme system (Dark, Light, System)
✅ Responsive design (mobile to desktop)
✅ Comprehensive tests (backend and frontend)
✅ End-to-end integration

## Technical Stack

- **Backend**: Go 1.21, Cobra, Gorilla Mux, Logrus
- **Frontend**: React 18, TypeScript, Tailwind CSS, Vite
- **Markdown**: React Markdown, remark-gfm
- **Testing**: Vitest, Testing Library, Go test
- **Build**: Makefile, npm scripts

## Verification

All requirements from SPEC.md have been met:
- ✅ CLI starts with defaults
- ✅ CRUD works end-to-end
- ✅ Static assets are properly served
- ✅ Theme switch & persistence
- ✅ Responsive at 320px and 1920px
- ✅ All tests passing