#!/usr/bin/env bash
set -eo pipefail

echo "---> Node Buildpack"

# 1. GET ARGS
layers_dir=$1
plan_path=$3

# shellcheck source=/dev/null
. generate-project.sh "${layers_dir}"

# 2. Install build deps
# shellcheck source=/dev/null
. generate-layers.sh "${layers_dir}"
generate_deps_layer build-deps
generate_deps_layer run-deps

# 3. install node
generate_stack_layer node "${plan_path}" true

# shellcheck source=/dev/null
. init-stack

# 4. install node modules
node_modules_layer_dir="${layers_dir}/node_modules"
mkdir -p "${node_modules_layer_dir}"/profile.d
# Compares previous package.json checksum to the current package.json
local_package_checksum=$(sha256sum package.json | cut -d ' ' -f 1 || echo 'not found')
remote_package_checksum='not found'
if [[ -f "${node_modules_layer_dir}.toml" ]]; then
  remote_package_checksum=$(yj <"${node_modules_layer_dir}.toml" -t | jq -r .metadata.version 2>/dev/null || echo 'not found')
fi

if [[ -f package.json && "${local_package_checksum}" == "${remote_package_checksum}" ]]; then
  echo "---> Reusing package.json"
elif [[ -f package.json ]]; then
  echo "---> Installing package.json with npm install."
  cp package.json "${node_modules_layer_dir}"
  cd "${node_modules_layer_dir}" && npm install && cd -
  cat >"${node_modules_layer_dir}.toml" <<EOL
[types]
cache = true
build = true
launch = true

[metadata]
version = "${local_package_checksum}"
EOL
  cat >"${node_modules_layer_dir}"/profile.d/copy_node_modules.sh <<EOL
# only execute at runtime
if [ -z "\$INIT_STACK" ]; then
  cp -rf ${node_modules_layer_dir}/node_modules $(pwd)
fi
EOL
fi

json_get_key() {
  local file="$1"
  local key="$2"

  if test -f "$file"; then
    jq -c -M --raw-output "$key // \"\"" <"$file" || return 1
  else
    echo ""
  fi
}

build_script=$(json_get_key "package.json" ".scripts.build")
if [[ $build_script ]]; then
  npm run build
fi

generate-launch.sh "${layers_dir}"