## Summary
Pre-compress the HTML file to save flash space. I'm using `gzip` because
it's supported everywhere (indeed, we are using the same optimization on
[llama.cpp server](https://github.com/ggml-org/llama.cpp), our HTML page
is huge 😅 ).
This free up ~40KB flash space.
Some users suggested using `brotli` which is known to further reduce 20%
in size, but it doesn't supported by firefox (only supports if served
via HTTPS), and some reverse proxy like nginx doesn't support it out of
the box (unrelated in this context, but just mention for completeness)
```
PR:
RAM: [=== ] 31.0% (used 101700 bytes from 327680 bytes)
Flash: [==========] 95.5% (used 6259244 bytes from 6553600 bytes)
master:
RAM: [=== ] 31.0% (used 101700 bytes from 327680 bytes)
Flash: [==========] 96.2% (used 6302416 bytes from 6553600 bytes)
```
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? **PARTIALLY**, only the
python part
## Summary
- **What is the goal of this PR?**
Implements wireless EPUB file management via a built-in web server,
enabling users to upload, browse, organize, and delete EPUB files from
any device on the same WiFi network without needing a computer cable
connection.
- **What changes are included?**
- **New Web Server**
([`CrossPointWebServer.cpp`](src/CrossPointWebServer.cpp),
[`CrossPointWebServer.h`](src/CrossPointWebServer.h)):
- HTTP server on port 80 with a responsive HTML/CSS interface
- Home page showing device status (version, IP, free memory)
- File Manager with folder navigation and breadcrumb support
- EPUB file upload with progress tracking
- Folder creation and file/folder deletion
- XSS protection via HTML escaping
- Hidden system folders (`.` prefixed, "System Volume Information",
"XTCache")
- **WiFi Screen** ([`WifiScreen.cpp`](src/screens/WifiScreen.cpp),
[`WifiScreen.h`](src/screens/WifiScreen.h)):
- Network scanning with signal strength indicators
- Visual indicators for encrypted (`*`) and saved (`+`) networks
- State machine managing: scanning, network selection, password entry,
connecting, save/forget prompts
- 15-second connection timeout handling
- Integration with web server (starts on connect, stops on exit)
- **WiFi Credential Storage**
([`WifiCredentialStore.cpp`](src/WifiCredentialStore.cpp),
[`WifiCredentialStore.h`](src/WifiCredentialStore.h)):
- Persistent storage in `/sd/.crosspoint/wifi.bin`
- XOR obfuscation for stored passwords (basic protection against casual
reading)
- Up to 8 saved networks with add/remove/update operations
- **On-Screen Keyboard**
([`OnScreenKeyboard.cpp`](src/screens/OnScreenKeyboard.cpp),
[`OnScreenKeyboard.h`](src/screens/OnScreenKeyboard.h)):
- Reusable QWERTY keyboard component with shift support
- Special keys: Shift, Space, Backspace, Done
- Support for password masking mode
- **Settings Screen Integration**
([`SettingsScreen.h`](src/screens/SettingsScreen.h)):
- Added WiFi action to navigate to the new WiFi screen
- **Documentation** ([`docs/webserver.md`](docs/webserver.md)):
- Comprehensive user guide covering WiFi setup, web interface usage,
file management, troubleshooting, and security notes
- See this for more screenshots!
- Working "displays the right way in GitHub" on my repo:
https://github.com/olearycrew/crosspoint-reader/blob/feature/connect-to-wifi/docs/webserver.md
**Video demo**
https://github.com/user-attachments/assets/283e32dc-2d9f-4ae2-848e-01f41166a731
## Additional Context
- **Security considerations**: The web server has no
authentication—anyone on the same WiFi network can access files. This is
documented as a limitation, recommending use only on trusted private
networks. Password obfuscation in the credential store is XOR-based, not
cryptographically secure.
- **Memory implications**: The web server and WiFi stack consume
significant memory. The implementation properly cleans up (stops server,
disconnects WiFi, sets `WIFI_OFF` mode) when exiting the WiFi screen to
free resources.
- **Async operations**: Network scanning and connection use async
patterns with FreeRTOS tasks to prevent blocking the UI. The display
task handles rendering on a dedicated thread with mutex protection.
- **Browser compatibility**: The web interface uses standard
HTML5/CSS3/JavaScript and is tested to work with all modern browsers on
desktop and mobile.
---------
Co-authored-by: Dave Allie <dave@daveallie.com>