README.typ

= RayGreet
  This document is generated by `README.typ` using #link("https://pandoc.org/")[pandoc].

  == Installation
    
    === Pre-requist
      + Install #link("https://ziglang.org/download/")[zig] programming language (version: master branch)
      + Clone this repo using command `git clone --single-branch -b main --depth=1 'https://git.sr.ht/~meow_king/raygreet'`
      + Clone #link("https://github.com/raysan5/raylib")[raylib] as `./lib/raylib`, you can run the following command
      ```bash
cd ./raygreet
rm ./lib/raylib # remove the original symbol link in this repo
git clone --single-branch -b master --depth=1 'https://github.com/raysan5/raylib.git' ./lib/raylib
      ```
      
    === Manually Build
      If you have #link("https://github.com/casey/just")[just] installed, then run command `just install`.
      Or you need to run the following command:
      ```bash
sudo zig build -Doptimize=ReleaseSafe -Dplatform_drm
sudo cp ./zig-out/bin/raygreet /usr/bin/raygreet
sudo chmod a+s /usr/bin/raygreet
      ```
      Check the file permission by `ls -l /usr/bin/raygreet`, if you see
      ```
      -rwsr-sr-x 1 root root 1052768 Feb 14 10:36 /usr/bin/raygreet
      ```
      and `s` is the fourth character and the file is owned by `root`, then we installed it successfully. \
      `s` means this file is always executed as the file owner (in this case, `root`), so we are in `input` group and can
      access `/dev/input/event*` files, which is required by Raylib. However, instead of
      ```
      sudo chmod a+s /usr/bin/raygreet
      ```
      You can also make `greeter` user in `input` group using the following command
      ```bash
      sudo usermod greeter -a -G input
      ```
    
  == Develop

    === Test in TTY
      + You need #link("https://git.sr.ht/~kennylevinsen/greetd/tree")[fakegreet], which can built with the following command
      ```bash
git clone --single-branch -b master --depth=1 'https://git.sr.ht/~kennylevinsen/greetd'
cd ./greetd
cargo build # use `--release` to build in release mode
cp ./target/debug/fakegreet ~/.local/bin/
      ```
      + Change to `TTY<number>` using key `Ctrl + Alt + F<number>`
      + then run `just run-drm` or
      ```bash
zig build -Dplatform_drm
sudo fakegreet "./zig-out/bin/raygreet"
      ```

  == Current Issues
    
    1. Only officially support US keyboards. Other keyboards may have wrong mappings for some keys.
    It is due to that Raylib currently uses a US keymap to map #link("https://en.wikipedia.org/wiki/Scancode")[scancode]
    to key code. See #link("https://github.com/raysan5/raylib/blob/7ec43022c177cbf00b27c9e9ab067bd6889957a4/src/platforms/rcore_drm.c#L145")[raylib source]. \
    You can test it in TTY to see if it works correctly.

    Here is the #link("https://github.com/raysan5/raylib/discussions/3773")[discussion]. 
    
    Developer notes: \
    1. evdev key code:  /usr/share/X11/xkb/keycodes/evdev
    2. scancode: /usr/include/linux/input-event-codes.h

= TODO
  1. support choosing start session at runtime (and store the last choice)