#!/bin/bash
DirName="$(basename "$PWD" | tr '[:upper:]' '[:lower:]')"
ServiceName="$1"
ContainerName="$(docker ps --format '{{.Names}}' | grep "${DirName}_${ServiceName}" | head -n 1)"

if [ $# == 0 ]; then
  echo >&2 'usage: dsh <service name> [...command]'
  exit 1
fi

if [ -z "$ContainerName" ]; then
  echo >&2 "error: no container "${DirName}_${ServiceName}" found"
  exit 1
fi

shift 1
case $# in
  0) docker exec -ti "$ContainerName" /bin/bash ;;
  *) docker exec -ti "$ContainerName" "$@" ;;
esac