#!/bin/sh
# =============================================== #
# enter.sh v1.0; job79                            #
# Enter into an existing or new dev container and #
# automatically handle dev container updates.     #
# =============================================== #
set -e

# podman_run opens a shell into a newly created dev container.
podman_run() {
  args="--name $name"
  arg() { args="$args $@"; }

  # Automatically update the container when a newer
  # image is available.
  [ "$no_pull" = 1 ] || arg "--pull newer"

  # Disable some security settings to make it possible to mount
  # host directories without problems.
  arg "--security-opt label=disable" # disable labeling so mounts don't need to be labbeled.
  arg "--userns=keep-id"             # required for ~/.ssh which is usually 700.
  arg "--net=host"                   # use host networking

  # Mount the wayland socket. Required to get the system
  # clipbard (wl-copy) working.
  arg "-v /run/user/$UID/wayland-0:/run/user/1000/wayland-0"

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

  # Mount host directories with programming projects.
  [ -d ~/Documents ] && arg "-v $HOME/Documents:/home/user/Documents"
  [ -d ~/.dev ] && arg "-v $HOME/.dev:/home/user/.dev"

  # Add volumes for .local and .cache so these survive
  # container restarts.
  arg "-v $name-local:/home/user/.local"
  arg "-v $name-cache:/home/user/.cache"
  podman run -it $args "$image"
}

# podman_exec opens a shell into an existing dev container.
podman_exec() { podman exec -it "$name" bash -l; }

# podman_start starts a stopped existing dev container.
podman_start() { podman start "$name" 1>/dev/null; }

# podman_delete deletes a dev container.
podman_delete() { podman container rm -f -t 1 "$name" 1>/dev/null; }

### MAIN ###
name="dev"
image="git.plabble.org/job79/dev:latest"

while test $# -gt 0; do
  case "$1" in
  --recreate | -r) podman_delete ;;
  --no-pull | -np) no_pull=1 ;;
  -*) echo "unknown option '$1'" ;;
  *) name="$1" ;;
  esac
  shift
done

if ! podman container exists "$name"; then
  podman_run
  exit
fi

if [ "$(podman container inspect "$name" -f {{.State.Running}} 2>&1)" = 'true' ]; then
  podman_exec
  exit
fi

if [ "$no_pull" = 1 ]; then
  podman_start
  podman_exec
  exit
fi

iid="$(podman image inspect "$image" -f {{.Id}})"
podman pull "$image"
if [ "$(podman image inspect "$image" -f {{.Id}})" != "$iid" ]; then
  # When container is stopped and a newer image is available,
  # recreate the container instead of starting the existing one.
  podman_delete
  podman_run
else
  podman_start
  podman_exec
fi