#! /usr/bin/env sh

FIRMWARE_URL="http://downloads.bremen.freifunk.net/firmware/"
LOCAL_SUFFIX="bremen"
GLUON_DIR="gluon/"
KEYFILE="$HOME/.ecdsakey"

set -eu

if which realpath > /dev/null; then
  GLUON_SITEDIR="$(dirname "$(realpath "$0")")"
else
  GLUON_SITEDIR="$(dirname "$(readlink -f "$0")")"
fi
export GLUON_SITEDIR

get_GLUON_TAG() {
  if ! git --git-dir="${GLUON_DIR}/.git" describe --exact-match; then
    echo 'The gluon tree is not checked out at a tag.'
    echo 'Please use `git checkout <tagname>` to use an official gluon release'
    echo 'or build it manually. Only with at a tag we can autogenerate the'
    echo 'release string!'
    exit 1
  fi
}

get_last_release() {
  branch="$1"
  wget -q -O- "${FIRMWARE_URL}/${branch}/sysupgrade/${branch}.manifest" | \
    awk 'parse == 1 { print $2; exit } /^$/ { parse=1 }'
}

is_based_on() {
  [ "${1#$2}" != "${1}" ]
  return $?
}

extract_local_version() {
  local_version_tmp="${1#*+${LOCAL_SUFFIX}}"
  echo "${local_version_tmp%~testing}"
}

if [ "$#" = 0 ]; then
  cat <<USAGE
Usage: $(basename $0) [--debug] <branch>

This script takes the intended branch, "testing" or "stable", as the single
parameter. It then tries to autodetermine the correct release name, builds
gluon for the corresponding branch and all supported platforms (excluding
x86*), and optionally signs it if an ecdsutils keyfile is found (standard path:
~/.ecdsakey)
USAGE
  exit 1
fi

debug=
if [ "$1" = "--debug" ]; then
    debug=1
    shift
fi

GLUON_BRANCH="$1"

if [ "$GLUON_BRANCH" != "testing" -a "$GLUON_BRANCH" != "stable" ]; then
  echo "Branch not supported yet!"
  exit 1
fi

GLUON_TAG="$(get_GLUON_TAG)"
# remove prefixed "v"
GLUON_TAG="${GLUON_TAG#v}"

statefile="${GLUON_SITEDIR}/.build.${GLUON_BRANCH}.${GLUON_TAG}"
cont=false

if [ -f "$statefile" ]; then
  echo "A previous build for this version was aborted."
  echo "These were the parameters:"
  cat "$statefile"
  echo "You can now either continue the previous build or begin a new one"
  echo "and overwrite the old state file."
  read -p "Do you want to continue the previous build? [Yn] " answer
  case "${answer:-y}" in
    [yY]*)
      . "$statefile"
      cont=true
      ;;
    *)
      rm "$statefile"
      ;;
  esac
fi
if ! $cont; then
  echo "Building Gluon ${GLUON_TAG} as ${GLUON_BRANCH}"
  last_release_testing="$(get_last_release testing)"
  last_release_stable="$(get_last_release stable)"
  echo "Last release in branch testing was ${last_release_testing}"
  if is_based_on "$last_release_testing" "$GLUON_TAG"; then
    local_version="$(extract_local_version "$last_release_testing")"
    if [ "$GLUON_BRANCH" != "stable" ]; then
      local_version="$(($local_version + 1))"
    fi
  elif [ "$GLUON_BRANCH" = "stable" ] && is_based_on "$last_release_stable" "$GLUON_TAG"; then
    local_version="$(extract_local_version "$last_release_stable")"
    local_version="$(($local_version + 1))"
  else
    # new gluon version => reset local version number
    local_version=1
  fi
  if [ "$GLUON_BRANCH" = "testing" ]; then
    local_version="${local_version}~testing"
  fi
  auto_determined_release="${GLUON_TAG}+${LOCAL_SUFFIX}${local_version}"
  read -p "Release name for this build [default: ${auto_determined_release}]: " GLUON_RELEASE
  GLUON_RELEASE="${GLUON_RELEASE:-$auto_determined_release}"

  cat > "$statefile" <<EOF
GLUON_TAG="${GLUON_TAG}"
GLUON_BRANCH="${GLUON_BRANCH}"
GLUON_RELEASE="${GLUON_RELEASE}"
EOF
fi

if [ "$GLUON_BRANCH" = "stable" ]; then
    export GLUON_PRIORITY=7
fi

# calculate number of threads
if [ -z "$debug" ]; then
    proc_num="$(($(grep -c '^processor\s' /proc/cpuinfo) + 1))"
else
    proc_num=1
fi

cd "$GLUON_DIR"
export GLUON_BRANCH GLUON_RELEASE
if ! $cont; then
  make update ${debug:+V=s}
fi

for target in ar71xx-generic ar71xx-nand mpc85xx-generic x86-generic; do
  env_target="$(echo "$target" | tr '-' '_')"
  set +u
  if eval "[ \"\$TARGET_${env_target}_DONE\" = 1 ]"; then
    continue
  fi
  set -u
  echo "Building target ${target}"
  if $cont; then
    cont=false
  else
    make clean GLUON_TARGET="$target" ${debug:+V=s}
  fi
  make -j${proc_num} GLUON_TARGET="$target" ${debug:+V=s}
  echo "TARGET_${env_target}_DONE=1" >> "$statefile"
done
make manifest
cd ..

if [ -n "$KEYFILE" -a -r "$KEYFILE" ]; then
  "${GLUON_DIR}/contrib/sign.sh" "$KEYFILE" "${GLUON_DIR}/output/images/sysupgrade/${GLUON_BRANCH}.manifest"
fi

rm "$statefile"