lianli_207_lcd: Instructions file for Codex

AGENTS.md - Lian Li Lancool 207 LCD Driver

Project Overview

Linux driver for the Lian Li Lancool 207 Digital LCD screen. This Python 3.12+ project communicates with the LCD via USB, renders system stats (CPU/GPU/RAM/Network), and pushes images to the display.

Build Commands

Installation

# Using uv (recommended)
uv sync

# Using pip
pip install -e .

System Installation (requires root)

# Install with systemd service (requires background image path)
sudo ./install.sh /path/to/background.jpg

# Reinstall/reload after changes
sudo ./reinstall.sh

# Uninstall completely
sudo ./uninstall.sh

# Check service status
journalctl -u lcd-driver -f

Running the driver (development)

lcd-driver <background_image>

Type checking (only tool configured)

# Run basedpyright
basedpyright lcd_driver/

# Or using pyright directly if installed
pyright lcd_driver/

Building the package

python -m build

Running a single test

No tests exist yet. To add tests, use pytest:

pytest tests/                    # Run all tests
pytest tests/test_file.py        # Run specific test file
pytest tests/test_file.py::test_function_name  # Run specific test

Code Style Guidelines

General

• Python 3.12+ required
• Follow PEP 8 with 100 character line limit
• Use type hints for all function signatures and variables when beneficial
• Run basedpyright before committing - it must pass without errors

Imports

• Standard library imports first
• Third-party imports second
• Local imports last
• Use absolute imports (e.g., from lcd_driver import foo)
• Separate import groups with a single blank line

# Correct
import os
import sys
import struct
import time

import usb.core
import usb.util
from PIL import Image, ImageDraw, ImageFont

from lcd_driver import utils

Naming Conventions

• Use snake_case for functions, variables, and methods
• Use SCREAMING_SNAKE_CASE for constants
• Use PascalCase for classes
• Use descriptive names - avoid single letters except in tight loops