#!/bin/bash -eux
#
# Copyright (C) 2023 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

# This script is used to build widevine apex bundle

readonly -a ARCHS=(
  "arm"
  "arm64"
  "arm64only"
  "x86"
  "x86_64"
  "x86_64only"
)


function die() { format=$1; shift; printf >&2 "$format\n" "$@"; exit 1; }


# $@: additional build targets
# inputs: none
# outputs: ${DIST_DIR}/${arch}/${apex}-base.zip
function build_modules() {
  # keep DIST_DIR to override for each arch
  local dist_dir="${DIST_DIR}"
  for arch in "${ARCHS[@]}"; do
    # override DIST_DIR for each arch
    DIST_DIR="${dist_dir}/${arch}" \
    TARGET_PRODUCT="widevine_generic" \
    TARGET_BASE_PRODUCT="build/target/product/module_${arch}.mk" \
    build/soong/soong_ui.bash --make-mode "$@" \
        ALWAYS_EMBED_NOTICES=true \
        apps_only \
        dist \
        lint-check
  done
  # restore DIST_DIR
  DIST_DIR="${dist_dir}"
}


# $1: apex
# inputs: ${DIST_DIR}/${arch}/${apex}-base.zip
# outputs: ${DIST_DIR}/${apex}.aab
function build_bundle() {
  local -r apex=$1

  # collect base.zip files
  local -a zips
  for arch in "${ARCHS[@]}"; do
    zips+=("${DIST_DIR}/${arch}/${apex}-base.zip")
  done
  local -ra zips

  # extract bundle_config.json from one of zip files
  unzip -o -d "${TMPDIR}/${apex}" "${zips[0]}" bundle_config.json

  # merge base.zip files
  local -r base_zip="${TMPDIR}/${apex}/base.zip"
  ${MERGE_ZIPS} \
    -ignore-duplicates \
    -stripFile bundle_config.json \
    "${base_zip}" \
    "${zips[@]}"

  # Use prebuilt bundletool JAR
  # build bundle
  "${JAVA_EXE}" -jar "${BUNDLETOOL_PREBUILT_JAR}" build-bundle \
    --overwrite \
    --modules "${base_zip}" \
    --config "${TMPDIR}/${apex}/bundle_config.json" \
    --output "${DIST_DIR}/${apex}.aab"
}


# inputs: ${DIST_DIR}/${arch}/${apex}-base.zip
# outputs: ${DIST_DIR}/${apex}.aab
function build_bundles() {
  # Assume TARGET_BUILD_APPS is set in the environment
  local app
  for app in ${TARGET_BUILD_APPS}; do
    build_bundle "${app}"
  done
}


# inputs: ${DIST_DIR}/${apex}.aab
# outputs: ${DIST_DIR}/dev_keys_signed/${apex}/${apex}.apks
function sign_bundles() {
  ${DEV_SIGN_BUNDLE} \
    --java_binary_path "${JAVA_EXE}" \
    --input_dir "${DIST_DIR}" \
    --output_dir "${DIST_DIR}/dev_keys_signed"
}


function configure_build() {
  # Assign to a variable and eval that, since bash ignores any error status from
  # the command substitution if it's directly on the eval line.
  local -r vars="$(TARGET_PRODUCT='' build/soong/soong_ui.bash --dumpvars-mode \
    --vars="ANDROID_JAVA_HOME TMPDIR OUT_DIR TARGET_BUILD_APPS DIST_DIR")"
  eval "${vars}"

  # Define prebuilt bundletool path and JAVA_EXE
  # Assume exactly one JAR matches
  local -a jar_matches=(prebuilts/bundletool/bundletool-all-*.jar)
  declare -gr BUNDLETOOL_PREBUILT_JAR="${jar_matches[0]}"
  declare -gr JAVA_EXE="${ANDROID_JAVA_HOME}/bin/java"

  # Keep declarations for built tools
  declare -gr MERGE_ZIPS=${OUT_DIR}/host/linux-x86/bin/merge_zips
  declare -gr DEV_SIGN_BUNDLE=${OUT_DIR}/host/linux-x86/bin/dev_sign_bundle
}


function main() {
  [[ -e "build/make/core/Makefile" ]] || die "$0 must be run from the top of the Android source tree."
  configure_build

  build_modules merge_zips dev_sign_bundle
  build_bundles # use prebuilt bundletool & merge_zips
  sign_bundles # use built dev_sign_bundle
}


main