#!/bin/bash

# Copyright 2022 The Fuchsia Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

set -e

# This script is used to fetch the prebuilt that is needed by driver build.

readonly REPO_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." >/dev/null 2>&1 && pwd)"
readonly BAZELISK_TOOL="${REPO_ROOT}/tools/bazel"
readonly OVERRIDE_SDK="${REPO_ROOT}/fuchsia_sdk.tar.gz"
readonly WORKSPACE_NAME="$(basename "$REPO_ROOT")"
readonly SDK_WORKSPACE_DIR="${REPO_ROOT}/bazel-${WORKSPACE_NAME}/external/fuchsia_sdk"

function get_os {
  uname -s | tr '[:upper:]' '[:lower:]'
}

function get_arch {
  local ARCH="$(uname -m)"
  case "${ARCH}" in
    x86_64)
      ARCH=amd64
      ;;
    aarch64)
      ARCH=arm64
      ;;
  esac
  echo "$ARCH"
}

create_symlink() {
  local TOOL
  TOOL="$1"
  SYMLINK="$2"
  mkdir -p "$(dirname "${SYMLINK}")"
  ln -f -s "${TOOL}" "${SYMLINK}"
}

create_bazel_symlink() {
  local BAZELISK_BIN="${REPO_ROOT}/vendor/bazelisk/bazelisk-$(get_os)-$(get_arch)"
  if [[ ! -x "${BAZELISK_BIN}" ]]; then
     >&2 echo "Bazel wrapper not supported in this OS/architecture. Could not find executable: ${BAZELISK_BIN}"
     exit 1
  fi
  create_symlink "$BAZELISK_BIN" "$BAZELISK_TOOL"
}

create_tools_symlinks() {
  create_symlink "${SDK_WORKSPACE_DIR}/tools/x64/ffx" ${REPO_ROOT}/tools/ffx
}

# TODO: this is probably not needed when the DDK becomes part of the core SDK.
update_sdk_from_archive() {
  SDK_ARCHIVE="$1"
  if [[ ! -f "$SDK_ARCHIVE" ]]; then
    echo "ERROR: sdk archive cannot be found: $SDK_ARCHIVE"
    exit 1
  fi
  echo "Copying SDK archive to ${OVERRIDE_SDK}..."
  rsync --checksum "$SDK_ARCHIVE" "$OVERRIDE_SDK"
  echo "Done copying SDK archive."
}

# TODO: this is probably not needed when the DDK becomes part of the core SDK.
update_sdk_from_local_build() {
  SDK_OUT="$1"
  PBM_OUT="$2"
  if [[ ! -d "$SDK_OUT" ]]; then
    echo "ERROR: cannot find a directory in $SDK_OUT"
    exit 1
  fi
  if [[ ! -d "$PBM_OUT" ]]; then
    echo "ERROR: cannot find a directory in $PBM_OUT"
    exit 1
  fi

  PBM_FILES=(
      $PBM_OUT/./gen/build/images/virtual_device.json
      $PBM_OUT/./gen/build/images/emulator_flags.json.template
      $PBM_OUT/./gen/build/images/product_bundle.json
      $PBM_OUT/./obj/build/images/fuchsia/fuchsia/fvm.blk
      $PBM_OUT/./multiboot.bin
      $PBM_OUT/./fuchsia.zbi
      $SDK_OUT/./amber-files
  )
  SDK_ARCHIVE="${SDK_OUT}/sdk/archive/core.tar.gz"
  DDK_ARCHIVE="${SDK_OUT}/sdk/archive/ddk.tar.gz"
  if [[ ! -f "$SDK_ARCHIVE" ]]; then
    echo "ERROR: cannot find the core SDK archive, make sure your 'fx set' has"
    echo "       '--args=build_sdk_archives=true' and that you build"
    echo "       'fx build :default sdk sdk:ddk': $SDK_ARCHIVE"
    exit 1
  fi
  if [[ ! -f "$DDK_ARCHIVE" ]]; then
    echo "ERROR: cannot find the DDK archive, make sure your 'fx set' has"
    echo "       '--args=build_sdk_archives=true' and that you build"
    echo "       'fx build :default sdk sdk:ddk': $DDK_ARCHIVE"
    exit 1
  fi

  for f in "${PBM_FILES[@]}"; do
    if [[ ! -e "$f" ]]; then
      echo "ERROR: cannot find file needed to run the emulator. Make sure your"
      echo "       'fx set' does NOT have '--args=build_sdk_archives=true'"
      echo "       and that you build with 'fx build :default sdk': $f"
      exit 1
    fi
  done

  if [[ -d "$OVERRIDE_SDK" ]]; then
    echo "Removing old SDK in $OVERRIDE_SDK"
    rm -f "$OVERRIDE_SDK"
  fi

  echo "Syncing SDK from local build..."
  TMP_CORE_DIR="$(mktemp -d)"
  TMP_DDK_DIR="$(mktemp -d)"
  tar xzf "${SDK_OUT}/sdk/archive/core.tar.gz" -C "${TMP_CORE_DIR}"
  tar xzf "${SDK_OUT}/sdk/archive/ddk.tar.gz" -C "${TMP_DDK_DIR}"
  mv "${TMP_DDK_DIR}/meta/manifest.json" "${TMP_DDK_DIR}/meta/ddk_manifest.json" 

  rsync -aR "${PBM_FILES[@]}" "$TMP_CORE_DIR"
  tar czvf "$OVERRIDE_SDK" -C "$TMP_CORE_DIR" . -C "$TMP_DDK_DIR" .
  rm -Rf "$TMP_CORE_DIR" "$TMP_DDK_DIR"
  echo "Done syncing SDK from local build."
}

syntax() {
    echo "   $(basename $0)"
    echo "      fetch from CIPD the SDK defined in WORKSPACE.bazel or use"
    echo "      ${OVERRIDE_SDK##REPO_ROOT/} if one is present."
    echo
    echo "   $(basename $0) --sdk-archive SDK_TARGZ"
    echo "      load an SDK and the emulator product bundle files from the"
    echo "      given tar.gz archive. See README.md on how to generate this archive."
    echo
    echo "   $(basename $0) --sdk-local FUCHSIA_OUT_SDK --product-bundle-local FUCHSIA_OUT_PRODUCT_BUNDLE"
    echo "      copy the SDK from a build directory of a local Fuchsia tree,"
    echo "      and copy the product bundle files for the emulator from another"
    echo "      build directory. See README.md for more information."
}

main() {
  if [[ $# -gt 0 ]]; then
    if [[ "$1" == "--sdk-archive" && $# -eq 2 ]]; then
      update_sdk_from_archive "$2"
    elif [[ $# -eq 4 && "$1" == "--sdk-local" && "$3" == "--product-bundle-local" ]]; then
      update_sdk_from_local_build $2 $4
    elif [[ $# -eq 4 && "$3" == "--sdk-local" && "$1" == "--product-bundle-local" ]]; then
      update_sdk_from_local_build $4 $2
    else
      echo "Invalid syntax."
      syntax
      exit 1
    fi
  fi

  create_bazel_symlink
  create_tools_symlinks
  # symlink to compile commands
  ln -f -s "${REPO_ROOT}/bazel-bin/src/compile_commands.json" "${REPO_ROOT}/compile_commands.json"
}

main "$@"