#!/bin/sh
#
# Copyright © 2018 Red Hat, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#


source /etc/os-release

toolbox_container="fedora-toolbox-$USER:$VERSION_ID"
toolbox_prompt="🔹[\u@\h \W]\\$ "

base_toolbox_image="fedora-toolbox:$VERSION_ID"
toolbox_image="fedora-toolbox-$USER:$VERSION_ID"
working_container_name="fedora-toolbox-$USER-working-container"


create()
{
    if ! buildah images --noheading | grep --quiet $toolbox_image; then
        if ! buildah from --name $working_container_name $base_toolbox_image >/dev/null 2>&1; then
            echo "$0: failed to create working container"
            exit 1
        fi

        if ! buildah containers --noheading | grep --quiet $working_container_name; then
            echo "$0: failed to create working container"
            exit 1
        fi

        if ! buildah run $working_container_name -- useradd \
                     --no-create-home \
                     --uid $UID \
                     --groups wheel \
                     $USER \
                     >/dev/null 2>&42; then
            buildah rmi $working_container_name >/dev/null 2>&42
            echo "$0: failed to create user $USER with UID $UID"
            exit 1
        fi

        if ! buildah run $working_container_name -- passwd -d $USER >/dev/null 2>&42; then
            buildah rmi $working_container_name >/dev/null 2>&42
            echo "$0: failed to remove password for user $USER"
            exit 1
        fi

        if ! buildah config --volume $HOME $working_container_name >/dev/null 2>&42; then
            buildah rmi $working_container_name >/dev/null 2>&42
            echo "$0: failed to configure volume for $HOME"
            exit 1
        fi

        if ! buildah config --volume $XDG_RUNTIME_DIR $working_container_name >/dev/null 2>&42; then
            buildah rmi $working_container_name >/dev/null 2>&42
            echo "$0: failed to configure volume for /run/user/$UID"
            exit 1
        fi

        if ! buildah config --user $USER $working_container_name >/dev/null 2>&42; then
            buildah rmi $working_container_name >/dev/null 2>&42
            echo "$0: failed to configure the default user as $USER"
            exit 1
        fi

        if ! buildah config --workingdir $HOME $working_container_name >/dev/null 2>&42; then
            buildah rmi $working_container_name >/dev/null 2>&42
            echo "$0: failed to configure the initial working directory to $HOME"
            exit 1
        fi

        if ! buildah commit --rm $working_container_name $toolbox_image >/dev/null 2>&42; then
            buildah rmi $working_container_name >/dev/null 2>&42
            echo "$0: failed to create image $toolbox_image"
            exit 1
        fi
    fi

    if ! podman create \
                 --hostname toolbox \
                 --interactive \
                 --name $toolbox_container \
                 --network host \
                 --privileged \
                 --security-opt label=disable \
                 --tty \
                 --volume $HOME:$HOME \
                 --volume $XDG_RUNTIME_DIR:$XDG_RUNTIME_DIR \
                 $toolbox_image \
                 /bin/sh >/dev/null 2>&42; then
        echo "$0: failed to create container $toolbox_container"
        exit 1
    fi
}


enter()
{
    if ! podman start $toolbox_container >/dev/null 2>&42; then
        echo "$0: failed to start container $toolbox_container"
        exit 1
    fi

    podman exec \
            --env COLORTERM=$COLORTERM \
            --env DBUS_SESSION_BUS_ADDRESS=$DBUS_SESSION_BUS_ADDRESS \
            --env DESKTOP_SESSION=$DESKTOP_SESSION \
            --env DISPLAY=$DISPLAY \
            --env LANG=$LANG \
            --env PS1="$toolbox_prompt" \
            --env SHELL=$SHELL \
            --env SSH_AUTH_SOCK=$SSH_AUTH_SOCK \
            --env TERM=$TERM \
            --env VTE_VERSION=$VTE_VERSION \
            --env XDG_CURRENT_DESKTOP=$XDG_CURRENT_DESKTOP \
            --env XDG_DATA_DIRS=$XDG_DATA_DIRS \
            --env XDG_MENU_PREFIX=$XDG_MENU_PREFIX \
            --env XDG_RUNTIME_DIR=$XDG_RUNTIME_DIR \
            --env XDG_SEAT=$XDG_SEAT \
            --env XDG_SESSION_DESKTOP=$XDG_SESSION_DESKTOP \
            --env XDG_SESSION_ID=$XDG_SESSION_ID \
            --env XDG_SESSION_TYPE=$XDG_SESSION_TYPE \
            --env XDG_VTNR=$XDG_VTNR \
            --interactive \
            --tty \
            $toolbox_container \
            $SHELL -l 2>&42
}


usage()
{
    echo "Usage: $0 [-v | --verbose ] create"
    echo "   or: $0 [-v | --verbose ] enter"
    echo "   or: $0 --help"
}


exec 42>/dev/null

while [[ "$1" == -* ]]; do
    case $1 in
        -h | --help )
            usage
            exit
            ;;
        -v | --verbose )
            exec 42>&2
            ;;
        * )
            echo "$0: unrecognized option '$1'"
            echo "Try '$0 --help' for more information."
            exit 1
    esac
    shift
done

if [ "$1" == "" ]; then
    echo "$0: missing command"
    echo "Try '$0 --help' for more information."
    exit 1
fi

op=$1
case $op in
    create )
        create
        exit
        ;;
    enter )
        enter
        exit
        ;;
    * )
        echo "$0: unrecognized command '$1'"
        echo "Try '$0 --help' for more information."
        exit 1
esac