#!/bin/bash

# ---------------------------------------------------------------------------
# build.sh – Build and push Docker images
#
# Usage:
#   ./build.sh [OPTIONS]
#
# Options:
#   -s, --snapshot            Version from git ref for prototyping
#   -r, --release             Version from .env for releases
#   -v, --version VERSION     Custom version
#   -p, --push                Push images after build
#   -o, --only SERVICE        Only build this service (repeatable)
#   -h, --help                Show this help
#
# Examples:
#   ./build.sh -r -p
#   ./build.sh -s -o frontend
#   ./build.sh -v dev -o backend -o frontend
# ---------------------------------------------------------------------------

# -e: Exit immediately if any command returns a non-zero exit code
# -u: Treat unset variables as errors
# -o pipefail: Make pipelines fail if any command in the pipe fails, not just the last one
set -euo pipefail

#cd to script dir
pushd "$(dirname "${BASH_SOURCE[0]}")" > /dev/null
SCRIPT_DIR="$(pwd)"
source "${SCRIPT_DIR}/.env"
# read from .env: 
#   REGISTRY, IMAGE_NAME, IMAGE_VERSION, SNAPSHOT_TAG
#   SERVICES (subfolder name = image suffix)
popd > /dev/null

#default: build snapshot
VERSION="${IMAGE_VERSION}-${SNAPSHOT_TAG}" # read from .env

PUSH=false
ONLY=()

usage() {
  sed -n '/^# Usage:/,/^# ---/p' "$0" | sed 's/^# //' | sed 's/^#//'
  exit 0
}

# --- parse arguments -------------------------------------------------------
while [[ $# -gt 0 ]]; do
  case $1 in
    -s|--snapshot)  VERSION="${IMAGE_TAG}-SNAPSHOT$(git rev-parse --short HEAD 2>/dev/null || echo "local")"; shift ;;
    -r|--release)   VERSION="${IMAGE_TAG}"; shift ;;
    -v|--version)   VERSION="$2"; shift 2 ;;
    -p|--push)      PUSH=true; shift ;;
    -o|--only)      ONLY+=("$2"); shift 2 ;;
    -h|--help)      usage ;;
    *) echo "Unknown option: $1" >&2; exit 1 ;;
  esac
done

# if --only was given, filter SERVICES down to those entries
if [[ ${#ONLY[@]} -gt 0 ]]; then
  SERVICES=("${ONLY[@]}")
fi

echo "============================================"
echo "  Docker Build - ${IMAGE_NAME}"
echo ""
echo "  Services : ${SERVICES[*]}"
echo "  Version  : ${VERSION}"
echo "  Registry : ${REGISTRY}"
echo "  Push     : ${PUSH}"
echo "============================================"

# --- build ------------------------------------------------------------------
for SERVICE in "${SERVICES[@]}"; do
  IMAGE="${REGISTRY}/${IMAGE_NAME}-${SERVICE}:${VERSION}"
  echo ""
  echo ">>> Building ${SERVICE}: ${IMAGE}"
  docker build --tag "${IMAGE}" "${SCRIPT_DIR}/${SERVICE}"
  echo "    ${SERVICE} built successfully."
done

# --- push -------------------------------------------------------------------
if $PUSH; then
  docker login "${REGISTRY}" # read from .env
  for SERVICE in "${SERVICES[@]}"; do
    IMAGE="${REGISTRY}/${IMAGE_NAME}-${SERVICE}:${VERSION}"
    echo ""
    echo ">>> Pushing ${IMAGE}"
    docker push "${IMAGE}"
  done
  echo ""
  echo "Images pushed successfully."
fi

echo ""
echo "Done."
for SERVICE in "${SERVICES[@]}"; do
  echo "  ${SERVICE} → ${REGISTRY}/${IMAGE_NAME}-${SERVICE}:${VERSION}"
done