#!/bin/bash

set -eu

function fail_one()
{
    echo >&2 "FAILURE when processing $CONTAINER_ID ($NAME_OF_CONTAINER), step: " "$@"
    RC=1
}

cd -P "$(dirname "$(readlink -f "$0")" )"

if [[ "$PWD" != "$(printf %q "$PWD" )" ]]
then
    echo >&2 "WARNING: path seems unsafe: $PWD"
fi

SCRIPT_ROOT="$PWD"
cd ..
INFRA_ROOT="$PWD"

CONTAINER_IDS=( "$@" )

if [[ "${#CONTAINER_IDS[@]}" == 0 ]]
then
    echo "No container ID supplied on command line, doing them all."
    mapfile -t CONTAINER_IDS < <( docker ps --format "{{.ID}}" )
fi

RC=0

echo Will process these containers:
printf '%s\n' "${CONTAINER_IDS[@]}"

for CONTAINER_ID in "${CONTAINER_IDS[@]}"
do
    echo "Processing $CONTAINER_ID"
    TMPFILE=$(mktemp)
    docker exec -u root $CONTAINER_ID bash -c "export LC_ALL=C ; apt-get update ; apt-get upgrade -y --dry-run" | tee $TMPFILE
    trap "rm $TMPFILE" EXIT
    if grep "0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded." $TMPFILE
    then
	echo "No update needed."
	continue
    fi

    PATH_OF_CONTAINER="$( docker inspect --format='{{ index .Config.Labels "com.docker.compose.project.working_dir" }}' $CONTAINER_ID )"
    NAME_OF_CONTAINER="$( docker inspect --format='{{ .Name }}' $CONTAINER_ID )"

    echo "IMPORTANT: updating container $NAME_OF_CONTAINER from $PATH_OF_CONTAINER"

    cd $PATH_OF_CONTAINER
    docker-compose pull || { fail_one "pull" ; continue ; }
    docker-compose build --no-cache || { fail_one "build" ; continue ; }
    docker-compose up -d || { fail_one "switch to newly built container" ; continue ; }
done