#!/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
#   -b, --backend-only        Only build backend
#   -f, --frontend-only       Only build frontend
#   -h, --help                Show this help
#
# Examples:
#   ./build.sh -r -p
#   ./build.sh -s -frontend-only
#   ./build.sh -v dev
# ---------------------------------------------------------------------------

# -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]}")"
SCRIPT_DIR="$(pwd)"
source "${SCRIPT_DIR}/.env"
popd

#default: snapshot
VERSION="${IMAGE_TAG}-SNAPSHOT$(git rev-parse --short HEAD 2>/dev/null || echo "local")"

PUSH=false
BUILD_BACKEND=true
BUILD_FRONTEND=true

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 ;;
    -b|--backend-only)  BUILD_FRONTEND=false; shift ;;
    -f|--frontend-only) BUILD_BACKEND=false; shift ;;
    -h|--help)       usage ;;
    *) echo "Unknown option: $1" >&2; exit 1 ;;
  esac
done

# --- derive image names -----------------------------------------------------
registry_prefix="${REGISTRY}/"
BACKEND_IMAGE="${registry_prefix}${IMAGE_NAME}-backend:${VERSION}"
FRONTEND_IMAGE="${registry_prefix}${IMAGE_NAME}-frontend:${VERSION}"

#SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

echo "============================================"
echo "  ${IMAGE_NAME} - Docker Build"
echo "  Version  : ${VERSION}"
echo "  Registry : ${REGISTRY}"
echo "  Push     : ${PUSH}"
echo "============================================"

# --- build ------------------------------------------------------------------
if $BUILD_BACKEND; then
  echo ""
  echo ">>> Building backend: ${BACKEND_IMAGE}"
  docker build \
    --tag "${BACKEND_IMAGE}" \
    "${SCRIPT_DIR}/backend"
  echo "    Backend built successfully."
fi

if $BUILD_FRONTEND; then
  echo ""
  echo ">>> Building frontend: ${FRONTEND_IMAGE}"
  docker build \
    --tag "${FRONTEND_IMAGE}" \
    "${SCRIPT_DIR}/frontend"
  echo "    Frontend built successfully."
fi

# --- push -------------------------------------------------------------------
if $PUSH; then
  docker login ${REGISTRY}

  if $BUILD_BACKEND; then
    echo ""
    echo ">>> Pushing ${BACKEND_IMAGE}"
    docker push "${BACKEND_IMAGE}"
  fi
  if $BUILD_FRONTEND; then
    echo ""
    echo ">>> Pushing ${FRONTEND_IMAGE}"
    docker push "${FRONTEND_IMAGE}"
  fi
  echo ""
  echo "Images pushed successfully."
fi

echo ""
echo "Done."
if $BUILD_BACKEND;  then echo "  Backend  → ${BACKEND_IMAGE}"; fi
if $BUILD_FRONTEND; then echo "  Frontend → ${FRONTEND_IMAGE}"; fi