#!/usr/bin/env bash
set -euo pipefail

image="${DEVENV_IMAGE:-devenv}"
container="${DEVENV_CONTAINER:-devenv}"
home_volume="${DEVENV_HOME_VOLUME:-${container}-home}"
build_context="${DEVENV_BUILD_CONTEXT:-https://github.com/zhuorantan/devenv.git}"
workspace="${PWD}"
root=0
action=run

usage() {
    cat <<EOF
Usage: $0 [-r|--root] [-w|--workspace DIR] [command...]
       $0 build [--local]
       $0 clean
       $0 reset

Options:
  --local          Build image from current directory instead of GitHub
  -r, --root           Run the container command as root
  -w, --workspace DIR  Host path mounted at /workspace

Environment:
  DEVENV_IMAGE      Image name to build/run, default: devenv
  DEVENV_BUILD_CONTEXT Docker build context, default: GitHub repo
  DEVENV_CONTAINER  Container name, default: devenv
  DEVENV_HOME_VOLUME Home volume name, default: <container>-home
EOF
}

build_image() {
    docker build -t "$image" "$build_context"
}

case "${1:-}" in
build)
    action=build
    shift
    ;;
clean)
    docker rm -f "$container" >/dev/null 2>&1 || true
    exit
    ;;
reset)
    printf 'Delete container %s and home volume %s? [y/N] ' "$container" "$home_volume" >&2
    read -r answer
    case "$answer" in
    y | Y | yes | YES) ;;
    *)
        printf 'Reset cancelled.\n' >&2
        exit
        ;;
    esac
    docker rm -f "$container" >/dev/null 2>&1 || true
    docker volume rm "$home_volume" >/dev/null 2>&1 || true
    exit
    ;;
-h | --help | help)
    usage
    exit
    ;;
esac

while [[ "$#" -gt 0 ]]; do
    case "$1" in
    --local)
        if [[ "$action" == "build" ]]; then
            build_context=.
            shift
        else
            usage >&2
            exit 2
        fi
        ;;
    -r | --root)
        root=1
        shift
        ;;
    -w | --workspace)
        [[ "${2:-}" ]] || {
            usage >&2
            exit 2
        }
        workspace="$2"
        shift 2
        ;;
    --)
        shift
        break
        ;;
    -*)
        usage >&2
        exit 2
        ;;
    *)
        break
        ;;
    esac
done

if [[ "$action" == "build" ]]; then
    build_image
    exit
fi

if ! docker image inspect "$image" >/dev/null 2>&1; then
    build_image
fi

uid="$(id -u)"
gid="$(id -g)"
home_mount=/home/me
if [[ "$root" == "1" ]]; then
    uid=0
    gid=0
    home_mount=/root
fi

args=(
    --name "$container"
    --hostname "$(hostname -s)-devenv"
    --rm
    -it
    --detach-keys ctrl-@,ctrl-@
    --security-opt seccomp=unconfined
    --security-opt apparmor=unconfined
    -e "HOST_UID=$uid"
    -e "HOST_GID=$gid"
    -v "$home_volume:$home_mount"
    -v "$workspace:/workspace"
)

if [[ -S /var/run/docker.sock ]]; then
    args+=(-v /var/run/docker.sock:/var/run/docker.sock)
fi

if [[ "$(uname -s)" == "Darwin" && -n "${SSH_AUTH_SOCK:-}" ]]; then
    args+=(
        -e SSH_AUTH_SOCK=/ssh-agent
        -v /run/host-services/ssh-auth.sock:/ssh-agent
    )
elif [[ -S "${SSH_AUTH_SOCK:-}" ]]; then
    args+=(
        -e SSH_AUTH_SOCK=/ssh-agent
        -v "$SSH_AUTH_SOCK:/ssh-agent"
    )
fi

docker run "${args[@]}" "$image" "$@"