#!/usr/bin/env bash
# Copyright 2017 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 -eo pipefail; [[ "${TRACE}" ]] && set -x

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

readonly CIPD_CLIENT_VERSION="${CIPD_CLIENT_VERSION:-$(cat ${SCRIPT_DIR}/.cipd_version)}"
readonly CIPD_CLIENT_URL="${CIPD_CLIENT_URL:-https://chrome-infra-packages.appspot.com}"

declare HOST_PLATFORM="$(uname -s | tr '[:upper:]' '[:lower:]')"
case "${HOST_PLATFORM}" in
  linux)
    readonly HOST_PLATFORM="linux"
    ;;
  darwin)
    readonly HOST_PLATFORM="mac"
    ;;
  *)
    echo "Unknown operating system."
    exit 1
esac

HOST_ARCH="$(uname -m | tr '[:upper:]' '[:lower:]')"
case "${HOST_ARCH}" in
  x86_64|amd64)
    readonly HOST_ARCH="amd64"
    ;;
  arm*)
    readonly HOST_ARCH="${HOST_ARCH}"
    ;;
  *86)
    readonly HOST_ARCH=386
    ;;
  *)
    echo "Unknown machine architecture."
    exit 1
esac

readonly URL="${CIPD_CLIENT_URL}/client?platform=${HOST_PLATFORM}-${HOST_ARCH}&version=${CIPD_CLIENT_VERSION}"
readonly CLIENT="${SCRIPT_DIR}/.cipd_client"

readonly USER_AGENT="buildtools/$(git -C ${SCRIPT_DIR} rev-parse HEAD 2>/dev/null || echo "???")"


# clean_bootstrap bootstraps the client from scratch using 'curl'.
function clean_bootstrap() {
  echo "Bootstrapping cipd client for ${HOST_PLATFORM}-${HOST_ARCH}..."
  local CLIENT_TMP="$(mktemp -p "${SCRIPT_DIR}" 2>/dev/null || mktemp "${SCRIPT_DIR}/.cipd_client.XXXXXXX")"
  if hash curl 2> /dev/null ; then
    curl -f --progress-bar "${URL}" -A "${USER_AGENT}"  -L -o "${CLIENT_TMP}"
    chmod +x "${CLIENT_TMP}"
  else
    echo "The \`curl\` command is missing, download ${URL} as ${CLIENT}, set +x, and then re-run this command" 1>&2
    exit 1
  fi
  mv "${CLIENT_TMP}" "${CLIENT}"
}

# self_update asks the existing client to update itself, if necessary.
function self_update() {
  "${CLIENT}" selfupdate -version "${CIPD_CLIENT_VERSION}" -service-url "${CIPD_CLIENT_URL}"
}

if [[ ! -x "${CLIENT}" ]]; then
  clean_bootstrap
fi

export CIPD_HTTP_USER_AGENT_PREFIX="${USER_AGENT}"
if ! self_update ; then
  echo -n "[31;1mCIPD selfupdate failed. " 1>&2
  echo "Trying to bootstrap the CIPD client from scratch... [0m" 1>&2
  clean_bootstrap
  if ! self_update ; then  # need to run it again to setup .cipd_version file
    echo -n "[31;1mBootstrap from scratch failed, something is seriously broken[0m " 1>&2
    echo "run \`CIPD_HTTP_USER_AGENT_PREFIX=${USER_AGENT}/manual ${CLIENT} selfupdate -version '${CIPD_CLIENT_VERSION}'\` to diagnose if this is repeating." 1>&2
    echo "[0m" 1>&2
  fi
fi

exec "${CLIENT}" "${@}"