#!/bin/bash
# =============================================== #
# enter.sh v2.0; job79                            #
# Dev container enter script. Handles setting up  #
# different dev containers, resuming sessions and #
# automatic container updates.                    #
# =============================================== #
set -eu
log() { printf '\e[%sm%s\e[0m %s\n' "${3:-36}" "${2:-○}" "$1"; }
arg() { echo -n " $@"; }

# run_args returns the podman run arguments required for
# starting a new container.
run_args() {
  arg "--name $name"

  # Disable some security settings so host directories can
  # be mounted without problems.
  arg "--security-opt label=disable" # disable labeling so mounts don't need to be labeled.
  arg "--userns=keep-id"             # required for ~/.ssh which is usually 700.

  # Configure options to get host-spawn to work inside the
  # container.
  [ -e "/run/user/$UID/bus" ] && arg "-v /run/user/$UID/bus:/tmp/bus" # Use host dbus.
  arg "-e HOST_HOME=$HOME"                                            # Used to translate container path to host.
  arg "-e CONTAINER_NAME=$name"

  # Use host networking.
  arg "--net=host"

  # Mount the wayland socket. Required to get the system
  # clipbard (wl-copy) and gui applications working.
  [ -e "/run/user/$UID/wayland-0" ] && arg "-v /run/user/$UID/wayland-0:/run/user/1000/wayland-0"
  arg "--device /dev/dri" # mount gpu devices for gpu acceleration.

  # Mount the ssh socket, directory and the git config
  # directory. This gets the host ssh and git configuration
  # working inside the container.
  [ -e "$SSH_AUTH_SOCK" ] && arg "-v $SSH_AUTH_SOCK:/run/user/1000/ssh-auth-sock"
  [ -d "$HOME/.ssh" ] && arg "-v $HOME/.ssh:/home/user/.ssh"
  [ -d "$HOME/.config/git" ] && arg "-v $HOME/.config/git:/home/user/.config/git"

  # Add a volume for the home directory so it survives
  # container updates.
  arg "-v $name:/home/user:copy"

  # Add custom user configuration.
  config_file="$script_dir/containers/$name/config.sh"
  [ -f "${config_file}" ] && source "${config_file}"
}

### MAIN ###
script_dir="$(dirname "$(realpath "$0")")"
name=$(<"$script_dir/state/last-name")
registry=$(<"$script_dir/state/registry")
pull=false

while test $# -gt 0; do
  case "$1" in
  -p) pull=true ;;
  -*) log "unknown argument '$1'" 'x' 31 ;;
  *)
    name="$1"
    echo "$1" >"$script_dir/state/last-name"
    ;;
  esac
  shift
done

if [ "$(podman container inspect "$name" -f {{.State.Running}} 2>&1)" != 'true' ] || [ "$pull" = true ]; then
  log "fetching devcontainer updates..."
  if [ "$(podman container inspect "$name" -f {{.Image}} 2>&1)" != "$(podman pull -q "$registry/$name" 2>&1)" ] || [ "$pull" = true ]; then
    if [ $? -eq 0 ]; then
      log "container image downloaded" '✓' 32
    else
      log "failed to download container image" 'x' 31
    fi
    podman container rm -f -t 1 "$name" 1>/dev/null
    podman run -td $(run_args) "$registry/$name"
  else
    log "no updates available" '✓' 32
  fi
fi

podman start "$name" 1>/dev/null
podman exec -e ENTER_DIR="${PWD/#$HOME/\~}" --detach-keys "ctrl-@" -it "$name" bash -l