#!/usr/bin/env bash
#
#   Licensed under the Apache License, Version 2.0 (the "License");
#   you may not use this file except in compliance with the License.
#   You may obtain a copy of the License at
#
#       http://www.apache.org/licenses/LICENSE-2.0
#
#   Unless required by applicable law or agreed to in writing, software
#   distributed under the License is distributed on an "AS IS" BASIS,
#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#   See the License for the specific language governing permissions and
#   limitations under the License.

if [ "${TESTPATCHDEBUG}" == "true" ] ; then
  set -x
fi

BASEDIR=$(pwd)
TASKNAME="MODERNIZER"
OP=""
TEMPDIR=""
REPORTDIR=""
STDOUT="/dev/null"
SUMMARYFILE=""

###############################################################################
cleanupAndExit() {
  exit "$1"
}
###############################################################################
printUsage() {
  echo "Usage: $0 --taskname | (--op=pre|post|report --tempdir=<TEMP DIR> --reportdir=<REPORT DIR> --summaryfile=<SUMMARY FILE>)"
  echo
}
###############################################################################
parseArgs() {
  for i in "$@"
  do
    case $i in
    --taskname)
      echo ${TASKNAME}
      exit 0
      ;;
    --op=*)
      OP=${i#*=}
      ;;
    --tempdir=*)
      TEMPDIR=${i#*=}
      ;;
    --reportdir=*)
      REPORTDIR=${i#*=}
      ;;
    --summaryfile=*)
      SUMMARYFILE=${i#*=}
      ;;
    --verbose)
      STDOUT="/dev/stdout"
      ;;
    -D*)
      MVNPASSTHRU="${MVNPASSTHRU} $i"
      ;;
    -P*)
      MVNPASSTHRU="${MVNPASSTHRU} $i"
      ;;
    esac
  done
  if [[ -z "${TASKNAME}" || -z "${OP}" || -z "${TEMPDIR}" || -z "${REPORTDIR}" || -z "${SUMMARYFILE}" ]]; then
    echo "Missing options"
    echo
    printUsage
    cleanupAndExit 1
  fi
  if [[ "${OP}" != "pre" && "${OP}" != "post" && "${OP}" != "report" ]] ; then
    echo "Invalid operation"
    echo
    printUsage
    cleanupAndExit 1
  fi
}
###############################################################################

verify_and_save_modernizer_output() {
  BRANCH_LABEL=$1
  REPORT_SUFFIX=$2
  output_txt=${REPORTDIR}/${TASKNAME}-${REPORT_SUFFIX}.txt

  echo "[TRACE] Saving modernizer output in ${BRANCH_LABEL}"
  echo "[TRACE] mvn clean compile modernizer:modernizer ${MVNPASSTHRU} | tee ${output_txt} >> ${STDOUT}"

  mvn clean compile modernizer:modernizer ${MVNPASSTHRU} | tee "${output_txt}" >> ${STDOUT}
  exitCode=${PIPESTATUS[0]}
  echo "EXITVALUE $exitCode" | tee -a "${output_txt}"
  echo "[TRACE] Modernizer output in ${BRANCH_LABEL} verified and saved"
}

check_modernizer_errors() {
    output_txt_clean="${REPORTDIR}/${TASKNAME}-clean.txt"
    output_txt_patch="${REPORTDIR}/${TASKNAME}-patch.txt"
    echo "[TRACE] grep -c '.*ERROR.*Prefer' ${output_txt_clean}"
    cleanModernizerErrors=$(grep -c '.*ERROR.*Prefer' "${output_txt_clean}")
    echo "[TRACE] Modernizer errors before patch: $cleanModernizerErrors"
    echo "[TRACE] grep -c '.*ERROR.*Prefer' ${output_txt_patch}"
    patchModernizerErrors=$(grep -c '.*ERROR.*Prefer' "${output_txt_patch}")
    echo "[TRACE] Modernizer errors after patch: $patchModernizerErrors"
    newModernizerErrors=$(( patchModernizerErrors - cleanModernizerErrors))

    if ! grep -lq 'EXITVALUE 0' "${output_txt_clean}"; then
        REPORT+=("{color:red}-1{color} Error during executing modernizer plugin on HEAD")
        return 1
    fi
    if ! grep -lq 'EXITVALUE 0' "${output_txt_patch}"; then
        REPORT+=("{color:red}-1{color} Error during executing modernizer plugin on PATCH")
        return 1
    fi

    if [ $newModernizerErrors -gt 0 ] ; then
        REPORT+=("{color:red}-1{color} the patch seems to introduce $newModernizerErrors new modernizer error(s)")
    fi

    if [ $newModernizerErrors -lt 0 ] ; then
        fixedModernizerErrors=$((-newModernizerErrors))
        REPORT+=("{color:green}+1{color} the patch fixes $fixedModernizerErrors modernizer error(s)")
    fi
    sed_extract="s@.*${BASEDIR}([^:]*):.*@\\1@g"

    cleanClassLines=$(grep '.*ERROR.*Prefer' "${output_txt_clean}" | sed -E "${sed_extract}" | sort | uniq -c)
    patchClassLines=$(grep '.*ERROR.*Prefer' "${output_txt_patch}" | sed -E "${sed_extract}" | sort | uniq -c)

    diffClassLines=$(diff <(echo "${cleanClassLines}") <(echo "${patchClassLines}") | grep '>\s*[^-]' | awk '{ print $3}')
    if [ -n "${diffClassLines}" ]; then
      for class_name in ${diffClassLines}; do
        oldErrorNumInClass=$(grep -c "${class_name}" "${output_txt_clean}")
        newErrorNumInClass=$(grep -c "${class_name}" "${output_txt_patch}")
        newErrorInClass=$(( newErrorNumInClass - oldErrorNumInClass ))
        if [ $newErrorInClass -gt 0 ] ; then
            REPORT+=("{color:red}-1{color} the patch introduces ${newErrorInClass} new warning(s) in ${class_name}")
        fi
      done
      return 1
    fi

    return 0
}

parseArgs "$@"

echo "  Running modernizer op=$OP"

case $OP in
  pre)
    verify_and_save_modernizer_output HEAD clean
    ;;
  post)
    verify_and_save_modernizer_output PATCH patch
    ;;
  report)
    REPORT=()
    if check_modernizer_errors; then
      echo "{color:green}+1 ${TASKNAME}{color}" >> "$SUMMARYFILE"
    else
      echo "{color:red}-1 ${TASKNAME}{color}" >> "$SUMMARYFILE"
    fi
    for line in "${REPORT[@]}" ; do
      echo ".    ${line}" >> "$SUMMARYFILE"
    done
    ;;
esac

exit 0