#!/bin/bash
declare targets=(dev arm amd deploy private multi)
declare OPTION; declare OPTARG; declare OPTIND

usage() {                                 # Function: Print a help message.
  echo "Image Build Script: Creates one or more images using a target in the docker-bake.hcl file"
  echo "USAGE: $0 <setup options> buildtarget <imagename, imageuser>"
  echo "valid targets: ${targets[*]};  default: dev"
  echo no argument options:
  echo "-c try out the image by starting a container terminal therein, for dev target this is the default;"
  echo "-x exclude distro from image name;"
  echo "-n for --no_cache"
  echo "-p push to repository; after build push to repository default is hub.docker.common (not need for deploy target)"
  echo required argument options:
  echo "-t <TAG> tag following : in output image name (i.e.  REPO/USER/NAME:TAG), default: latest"
  echo "-u <USER>;  repository user prefix in output image name (i.e.  REPO/USER/NAME:TAG)"
  echo "-r <REPO>;  private repo name, do not use for hub.docker.com (docker.io)"
  echo "-b <BASE_IMAGE>;  used in FROM in Dockerfile, default is official distro image (e.g. alpine:latest)"
}

exit_abnormal() {                         # Function: Exit with error.
  usage
  exit ${1:-1}
}


while getopts ':b:d:t:ncr:u:pxh' OPTION; do
  # echo processing: option:$OPTION argument:$OPTARG index:$OPTIND remaining:${@:$OPTIND}
  case "$OPTION" in
  b)
  # CUSTOM BASE IMAGE
    BASE_IMAGE=$OPTARG
    ;;
  d)
  #   LINUX_DISTRO=$OPTARG
    LINUX_DISTRO=$OPTARG
    ;;
  x)
  #  Exclude distro from image name
    exclude_distro=true
    ;;
  t)
    TAG=$OPTARG
    ;;
  u)
    RUSER=$OPTARG
    ;;
  c)
    try=true
      ;;
  p)
    push=true
      ;;
  n) 
    nocache="--no-cache" 
  ;;
  r)  
    REPO=$OPTARG
  ;;  
  h)  
    exit_abnormal 0
  ;;
  *)  
      echo "unknown $0 option -$OPTARG"
      exit_abnormal 4
  ;;
  esac
done

shift $((OPTIND - 1))

target=${1:-dev} 
LINUX_DISTRO=${LINUX_DISTRO:-alpine}
name=$2
RUSER=${3:-$RUSER}

IMAGE_NAME=$([[ $RUSER ]] && echo ${RUSER}/)${name}$([[ (! $exclude_distro) && $name ]] && echo "-")$([[ ! $exclude_distro ]] && echo ${LINUX_DISTRO})
if [[ $BASE_IMAGE ]]; then
echo determining DISTRO of base image: $BASE_IMAGE
 LINUX_DISTRO=$(./image-distro $BASE_IMAGE)
 [[ ! $LINUX_DISTRO ]] && echo "unable to get base image OS for: $BASE_IMAGE, aborting build" && exit 1
 else 
 BASE_IMAGE=$LINUX_DISTRO
fi

# BASE_IMAGE=$([[ $BASE_IMAGE == *:* ]] && echo $BASE_IMAGE || echo $BASE_IMAGE:latest)
#$([[ ! $BASE_IMAGE == *:* ]] && echo :latest)

export BASE_IMAGE
export TAG
export IMAGE_NAME
export LINUX_DISTRO

echo "building with base image: $BASE_IMAGE, output image name => $IMAGE_NAME"
echo "Linux Distro: $LINUX_DISTRO"
echo "***** using build target: $target  ****"
docker buildx bake --print $target
echo "******************"
read  -n 1 -p "do you want to continue [y]=>" REPLY
[[ $REPLY != "y" ]] && echo -e "\n" && exit 0

[[ ! "${targets[@]}" =~ $target ]] && echo $target is not a valid target && echo valid targets are: ${targets[@]} && exit 4

builder=default
if [ $target == "deploy" ]; then 
    builder=deploy 
    if ! docker buildx ls | grep -q deploy ; then
        echo multiarch deploy builder does not exist, creating with docker-container driver 
        docker buildx create --name deploy --driver docker-container >/dev/null
        docker buildx ls | grep deploy
    fi
fi

[[ $target == "private" && ! $REPO ]] && echo "must use '-r <private repo>' if building to private repo" && exit 3 

docker buildx --builder ${builder} bake ${nocache} ${target} 2>&1 | tee build.log

if [[ $target == "private" ]]; then 
    ./push -a -r $REPO $IMAGE_NAME
    ./push -r $REPO $IMAGE_NAME
  else 
    if [[ $push && (! $target == "dev")  ]];then 
      echo pushing now
      ./push $([[ $target == "arm" ]] && echo -a) -r $REPO $IMAGE_NAME
    fi
fi

[[ $try || $target == "dev" ]] && ./try $([[ $target == "deploy" ]] && echo -p)  $name $RUSER