#!/bin/bash
#
# Git post-receive hook to update Patchwork patches after Git pushes
#
# Copyright © 2010 martin f. krafft <madduck@madduck.net>
# Released under the GNU General Public License v2 or later.
set -eu

#TODO: the state map should really live in the repo's git-config

# Use semicolon as separator to allow for state names with spaces
STATE_MAP="refs/heads/master:Accepted;refs/heads/master-next:Master Next;refs/heads/ross/mut:Master Under Test;refs/heads/morty:morty-master;refs/heads/pyro:pyro-master;refs/heads/rocko:rocko-master"
#
# ignore all commits already present in these refs
# e.g.,
#   EXCLUDE="refs/heads/upstream refs/heads/other-project"
#
EXCLUDE=""

PWDIR=/usr/local/patchwork/patchwork

if [ -d "$PWDIR" ]; then
      if [ ! -w "$PWDIR/post-receive_logs" ]; then
              echo "E: Post-receive hook has no write permissions in patchwork path." >&2
              exit 1
      fi
else
      echo "E: Invalid patchwork path in post-receive hook" >&2
      exit 1
fi

do_exit=0
trap "do_exit=1" INT

# Create a folder for the post-receive hook logs
ERR_LOG_FILE=$PWDIR/post-receive_logs/post_receive.log
if [ ! -f "$ERR_LOG_FILE" ]; then
    mkdir -p "`dirname \"$ERR_LOG_FILE\"`" 2>/dev/null
fi

get_patchwork_hash()
{
  local hash
  hash="$(git -C $2 show -C $1 | python $PWDIR/parser.py --hash)"
  echo $hash
  test -n "$hash"
}

get_patch_id()
{
  local id
  id=$($PWDIR/bin/pwclient info -h $1 2>>$ERR_LOG_FILE \
    | sed -rne 's,- id[[:space:]]*: ,,p')
  echo $id
  test -n "$id"
}

set_patch_state()
{
  $PWDIR/bin/pwclient update -s $2 -c $3 $1 2>>$ERR_LOG_FILE
}

get_patch_state()
{
  state=$($PWDIR/bin/pwclient info $1 2>>$ERR_LOG_FILE \
    | sed -rne 's,- state[[:space:]]*: ,,p')
  echo $state
  test -n "$state"
}

update_patches()
{
  local cnt; cnt=0
  local workdir; workdir=$4
  local revparse;
  local revs;
  if [ -z "${EXCLUDE}" ]; then
    revparse="rev-parse"
  else
    revparse="rev-parse --not "${EXCLUDE}""
  fi
  revs=$(git -C "$workdir" "$revparse" |
         git -C "$workdir" rev-list --stdin --no-merges --reverse "${1}".."${2}")
  IFS=$'\n'; for rev in $revs; do
    if [ X"$do_exit" = X"1" ]; then
      echo "$(date) I: exiting..." >> $ERR_LOG_FILE 2>/dev/null
      break
    fi
    hash=$(get_patchwork_hash "$rev" "$workdir") \
      || { echo "$(date) E: failed to hash rev $rev." >> $ERR_LOG_FILE 2>/dev/null; continue; }
    id=$(get_patch_id $hash) \
      || { echo "$(date) E: failed to find patch for rev $rev." >> $ERR_LOG_FILE 2>/dev/null; continue; }
    state=""
    state=$(get_patch_state "$id") \
      || { echo "$(date) E: failed to find current state for patch ID-$id." >> $ERR_LOG_FILE 2>/dev/null; }
    if [ "$state" = "Accepted" ]; then
      echo "$(date) I: Skipping patch ID-$id because already is in \"Accepted\" state." >> $ERR_LOG_FILE 2>/dev/null; continue;
    fi
    reason="$(set_patch_state $id $3 $rev)" \
      || { echo "$(date) E: failed to update patch ID-$id${reason:+: $reason}." >> $ERR_LOG_FILE- 2>/dev/null; continue; }
    echo "$(date) I: patch ID-$id updated to state \"$3\" using commit $rev." >> $ERR_LOG_FILE 2>/dev/null
    cnt=$(($cnt + 1))
  done
  echo -e "$(date) I: $cnt patch(es) updated to state \"$3\"." >> $ERR_LOG_FILE 2>/dev/null
}

while read oldrev newrev refname workdir; do
  found=0
  IFS=';'
  for i in $STATE_MAP; do
    key="${i%:*}"
    IFS=' '
    if [ "$key" = "$refname" ]; then
      echo -e "\n$(date) I: Started patch-update attempt from commit $oldrev to commit $newrev." >> $ERR_LOG_FILE 2>/dev/null
      update_patches $oldrev $newrev "${i#*:}" $workdir
      found=1
      break
    fi
  done
  if [ $found -eq 0 ]; then
    echo "$(date) E: STATE_MAP has no mapping for branch $refname" >> $ERR_LOG_FILE 2>/dev/null
  fi
done