#!/usr/bin/env bash
set -eu
interactive_pkgs=libsdl2-dev
gem5=false
qemu=true
submodules='buildroot linux'
y=
while getopts gpqt OPT; do
  case "$OPT" in
    g)
      gem5=true
      ;;
    p)
      submodules="${submodules} parsec-benchmark"
      ;;
    q)
      qemu=false
      ;;
    t)
      interactive_pkgs=
      y=-y
      ;;
  esac
done
shift $(($OPTIND - 1))

## apt-get

pkgs="\
automake \
bc \
build-essential \
coreutils \
cpio \
expect \
git \
moreutils \
tmux \
unzip \
vinagre \
wget \
"
if "$gem5"; then
  pkgs="$pkgs \
ccache \
gcc-aarch64-linux-gnu \
gcc-arm-linux-gnueabi \
libgoogle-perftools-dev \
protobuf-compiler \
python-dev \
python-pip \
scons \
"
fi
command -v apt-get >/dev/null 2>&1 || {
  cat <<EOF
apt-get not found. You're on your own for installing dependencies.

On Ubuntu they are:

$pkgs
EOF
  exit 0
}

# Without this started failing in kernel 4.15 with:
# Makefile:932: *** "Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel".  Stop.                                                       
pkgs="$pkgs libelf-dev"

# https://stackoverflow.com/questions/20010199/determining-if-a-process-runs-inside-lxc-docker
if [ -f /.dockerenv ]; then
  # --jobs is not available in git 2.7.4 from Ubuntu 16.04.
  gitjobs=
  mysudo=
  # https://askubuntu.com/questions/496549/error-you-must-put-some-source-uris-in-your-sources-list
  sed -Ei 's/^# deb-src/deb-src/' /etc/apt/sources.list
  y=-y
else
  gitjobs="--jobs $(nproc)"
  mysudo=sudo
fi
$mysudo apt-get update $y
# Building SDL for QEMU in Buildroot was rejected upstream because it adds many dependencies:
# https://patchwork.ozlabs.org/patch/770684/
# We are just using the host SDL for now, if it causes too much problems we might remove it.
# libsdl2-dev needs to be installed separatedly from sudo apt-get build-dep qemu
# because Ubuntu 16.04's QEMU uses SDL 1.
$mysudo apt-get install $y \
  $pkgs \
  $interactive_pkgs \
;
if "$qemu"; then
  $mysudo apt-get build-dep $y qemu
fi
if "$gem5"; then
  # Generate graphs of config.ini under m5out.
  pip install --user pydot
fi

## Submodules

if "$qemu"; then
  submodules="${submodules} qemu"
fi
if "$gem5"; then
  submodules="${submodules} gem5"
fi
submodules="$(for submodule in ${submodules}; do printf "submodules/${submodule} "; done)"
(
  set -e
  # Shallow cloning saves a considerable amount of time, specially because of the linux kernel.
  # However, git submodules are buggy as usual, and this is the best way I've found to get it done:
  # https://stackoverflow.com/questions/2144406/git-shallow-submodules/47374702#47374702
  # In particular:
  # - `shallow = true` on the submodule has no effect for the non default educational branches of our submodules
  # - QEMU's submodules point to commits that are neither under branches nor tags, and so `--shallow-submodules` fails
  git submodule update --depth 1 $gitjobs --init -- ${submodules}
  if "$qemu"; then
    git -C submodules/qemu submodule update --init --recursive
  fi
) &
# https://unix.stackexchange.com/questions/65532/why-does-set-e-not-work-inside-subshells-with-parenthesis-followed-by-an-or
wait $! || git submodule update --init --recursive -- $submodules