#!/bin/bash -e

garlicPrefix=@garlicPrefix@
garlicTemp=@garlicTemp@
sshHost=@sshHost@
PATH=@PATH@

#garlicPrefix=/mnt/garlic
#garlicTemp=/tmp/garlic
#sshHost=mn1
#PATH=/nix/store/yjkcxbf0y1jdlbj0axghlg2fndc4dqkz-patchelf-0.11/bin:/nix/store/6is25fyx29d731idycngl7qmgcax5xng-gcc-wrapper-9.3.0/bin:/nix/store/h986r9i2j9x5z8i5g8aj0z8jdd129wyx-gcc-9.3.0/bin:/nix/store/48dypl6qdsj3vdzh7hjg5qnngfpdcz7h-glibc-2.31-bin/bin:/nix/store/zmac3n79ayg4fdqgznmi2v3lmcprzx4g-coreutils-8.31/bin:/nix/store/dmnnqr6j7kqgcr357b5qwiwvjvg2yyhd-binutils-wrapper-2.31.1/bin:/nix/store/gmi6xrkl95h6iypv00dvdpm3f4md9i6i-binutils-2.31.1/bin:/nix/store/48dypl6qdsj3vdzh7hjg5qnngfpdcz7h-glibc-2.31-bin/bin:/nix/store/zmac3n79ayg4fdqgznmi2v3lmcprzx4g-coreutils-8.31/bin:/nix/store/a41ky6icdgxa54jzps32gfgcrdyx94hs-rsync-3.1.3/bin:/nix/store/sxll2dlamfm32xd2nyfx7v8mlnx0gxks-openssh-8.3p1/bin:/nix/store/3gp7gv5z9jj3g92czxadvgphpwiviv28-nix-2.3.7/bin:/nix/store/zmac3n79ayg4fdqgznmi2v3lmcprzx4g-coreutils-8.31/bin:/nix/store/f2hn65ksj194nmy58nrjikv9r9w25irh-findutils-4.7.0/bin:/nix/store/m39n3m5c7r22b3ma2phnwmp0jj8a5jja-diffutils-3.7/bin:/nix/store/ray7jgwsr5xbxp28wvr427vywd08nz9s-gnused-4.8/bin:/nix/store/gzc092gzsanvym4c6sjgh22dsh9fzj4s-gnugrep-3.4/bin:/nix/store/mn412q9rz9afdrhl9v2ybf605r91wzl2-gawk-5.1.0/bin:/nix/store/xca341k5x5b4hcmi310gjhdlgqm4l56m-gnutar-1.32/bin:/nix/store/zvb8qad72bz6j7ia60dcsf3dfncxxqc7-gzip-1.10/bin:/nix/store/9pb8zp3zyykw09rg60f2nv32plamhd7h-bzip2-1.0.6.0.1-bin/bin:/nix/store/fm2p1d8w9sx4gbaf8qfv2rsailsyhvm3-gnumake-4.3/bin:/nix/store/npfsrhkjww5q7sax7p7ijcrj3wlbrxn7-bash-4.4-p23/bin:/nix/store/72m0m8v6mbp58vbngjgv5pn2scqhs6kk-patch-2.7.6/bin:/nix/store/7vh7fckk2srlkmmkfhs9y85icwm9rhj5-xz-5.2.5-bin/bin

usage() { echo "Usage: garlic [-RFwv] trebuchet" 1>&2; exit 1; }

findClosure() {
  what=$1
  from=$2
  mexp=$(nix-store -qR "$from" | grep -E -- "$what")
  n=$(echo "$mexp" | awk 'BEGIN { count=0 } NF { count++ } END { print count }')
  if [ $n -eq 0 ]; then
    >&2 echo "$exp: $what not found"
    exit 1
  fi
  if [ $n -gt 1 ]; then
    >&2 echo "$exp: multiple $what found"
    exit 1
  fi
  echo "$mexp"
}

findExperiment() {
  grep -o -- "/nix/store/.*-experiment" "$1"
}

drvFromOutput() {
  nix-store -q --deriver $1
}

checkTrebuchet() {
  if [ ! -e "$trebuchet" ]; then
    >&2 echo "$trebuchet: not found"
    exit 1
  fi

  if [ ! -f "$trebuchet" ]; then
    >&2 echo "$trebuchet: not a file"
    exit 1
  fi

  # FIXME: We need a better way to determine a trebuchet
  if [ -z "$(grep "This trebuchet launches" $trebuchet)" ]; then
    >&2 echo "$trebuchet: not a trebuchet"
    exit 1
  fi

  return 0
}

checkExperiment() {
  if [ ! -e "$experiment" ]; then
    >&2 echo "$experiment: not found"
    exit 1
  fi

  if [ ! -f "$experiment" ]; then
    >&2 echo "$experiment: not a file"
    exit 1
  fi

  # FIXME: We need a better way to determine a experiment
  if [ -z "$(grep "This is an experiment" $experiment)" ]; then
    >&2 echo "$experiment: not an experiment"
    exit 1
  fi

  return 0
}

checkMountpoint() {
  if [ ! -e "$garlicPrefix/garlic.control" ]; then
    >&2 echo "error: missing $garlicPrefix/garlic.control"
    >&2 echo "Is the mountpoint enabled?"
    exit 1
  fi
}

do_fetch() {
  expName=$(basename $experiment)
  user=$(ssh -G "$sshHost" | awk '/^user /{print $2}')
  exp=$garlicPrefix/$user/out/$expName

  if [ ! -e "$exp" ]; then
    echo "missing experiment: $exp"
    exit 1
  fi

  cwd=$(pwd)

  repeat=1
  while [ 1 ]; do
    repeat=0
    cd $exp
    test $verbose && >&2 echo "$exp: checking units"

    for unit in *-unit; do
      cd $exp/$unit
      if [ ! -e status ]; then
        
        test $verbose && >&2 echo "$unit: no status"
        repeat=1
      else
        st=$(cat status)
        test $verbose && >&2 echo "$unit: $st"
        if [ "$st" != "completed" ]; then
          repeat=1
        fi
      fi
    done

    if [ $repeat -eq 0 ]; then
      break
    fi

    if [ $waitResults -eq 1 ]; then
      #echo "waiting 3 seconds to try again"
      sleep 3
    else
      break
    fi
  done

  if [ $repeat -eq 1 ]; then
    >&2 echo "$exp: execution incomplete"
    exit 1
  fi

  cd "$cwd"

  test $verbose && >&2 echo "$exp: execution complete, fetching results"

  mkdir -p $garlicTemp

  rsync -rt --copy-links \
    --include='*/*/garlic_config.json' \
    --include='*/*/std*.log' \
    --include='*/*/*/std*.log' \
    --include='*/*/*/.garlic' \
    --include='*/*/*/.garlic/*' \
    --exclude='*/*/*/*' \
    $exp $garlicTemp

  nix-build -E "(with import ./default.nix; \
    garlic.pp.store { \
      experimentStage = import \"$experimentDrv\";
      trebuchetStage = import \"$trebuchetDrv\";
    })"

  rm -rf $garlicTemp/$expName
}

do_run() {

  >&2 $trebuchet
}

waitResults=1
verbose=
operation=
target=
enableRun=
enableFetch=

while getopts "vwRF" o; do
  case "${o}" in
    R) enableRun=1 ;;
    F) enableFetch=1 ;;
    w) waitResults=0 ;;
    v) verbose=1 ;;
    *) usage ;;
  esac
done
shift $((OPTIND-1))
trebuchet="$1"

if [ -z "$enableRun" -a -z "$enableFetch" ]; then
  >&2 echo "missing operation"
  usage
fi

if [ -z "$trebuchet" ]; then
  >&2 echo "missing experiment"
  usage
fi

checkMountpoint

checkTrebuchet $trebuchet

experiment=$(findExperiment "$trebuchet")
checkExperiment $experiment

trebuchetDrv=$(drvFromOutput $trebuchet)
experimentDrv=$(drvFromOutput $experiment)

if [ $enableRun ]; then do_run; fi
if [ $enableFetch ]; then do_fetch; fi