#!/bin/bash
# Purpose: detect modified files in config tree and execute
#          any defined service modifications
################################################################################

set -e
set -u

if ! [ -r /usr/share/ngcp-ngcpcfg/functions/main ] ; then
  printf "Error: /usr/share/ngcp-ngcpcfg/functions/main could not be read. Exiting.\n" >&2
  exit 1
fi

. /usr/share/ngcp-ngcpcfg/functions/main

# main script

cd "$CONFIG_POOL"

DRYRUN='false'
if [[ "${1:-}" == "test" ]] || [[ "${1:-}" == "--dry-run" ]]; then
  DRYRUN='true'
elif [[ -n "${1:-}" ]] ; then
  log_error "Unsupported option(s) given: $*"
  log_info  "Did you mean '--dry-run'?"
  exit 1
fi
log_debug "DRYRUN = $DRYRUN"

TMPFILE="$(mktemp)"

# unify service calls
unifyer() {
  file="$1"

  # make sure services are listed just once to
  # avoid re-execution of services (which will
  # happen if /etc/foo/ngcpcfg.services exists
  # and several file inside /etc/foo are modified)
  if ! grep -q "^${file}$" "$TMPFILE" ; then
    echo "$file" >> $TMPFILE
  fi
}

# NOTES:
# * 'git ls-files -o' also shows ignored files
# * 'git status --porcelain |grep '^?? ' not available in git 1.5

# The 'git diff' command fixes a strange race condition where 'git diff-index'
# lists *all* generated file(s) where the time stamp differs, resulting in a
# list of *all* generated files (which is not what we want).
# After running 'git diff' the following 'git diff-index ...' command lists
# only the modified files as we want and need it. See BTS #211 for bugreport.
git diff &>/dev/null

for file in $(git diff-index --name-only HEAD) ; do
  if [ -r "$file" ] && [ -r "${SERVICES_POOL}/${file}".services ] ; then
    log_debug "unifyer ${SERVICES_POOL}/${file}.services"
    unifyer "${SERVICES_POOL}/${file}".services
  elif [ -r "$file" ] && [ -r $SERVICES_POOL/"$(dirname $file)"/ngcpcfg.services ] ; then
    log_debug "unifyer ${SERVICES_POOL}/$(dirname $file)/ngcpcfg.services"
    unifyer "${SERVICES_POOL}"/"$(dirname $file)/ngcpcfg.services"
  fi
done

exec_wrapper() {
  # normalize path (get rid of "./" and "//")
  line="$(echo $1 | sed -e 's/\.\///g ; s/\/\//\//g')"

  if $DRYRUN ; then
    log_info "TEST MODE: Would execute action for ${line}"
    return 0
  fi

  log_info "Executing action for $line"
  if [ -x "$line" ] ; then
    log_debug "$line"
    if ! "$line" ; then
      log_warn "$line returned with error code, continuing anyway."
    fi
  elif [ -r "$line" ] ; then
    log_debug "bash $line"
    if ! bash "$line" ; then
      log_warn "$line returned with error code, continuing anyway."
    fi
  else
    log_error "Error: $line could not be read."
    exit 1
  fi
}

for line in $(cat $TMPFILE) ; do
  exec_wrapper "$line"
done

rm -f "$TMPFILE"

## END OF FILE #################################################################