#!/bin/bash

utility="clang-format"
utility_version="$("$utility" --version 2>/dev/null)" || {
  echo "$utility not found in path!"
  exit 1
}

regex="version ([0-9]+).([0-9]+).([0-9]+)"
declare -i major=0
declare -i minor=0
declare -i patch=0
declare -i required_major=9
declare -i required_minor=0
declare -i required_patch=0

if [[ "$utility_version" =~ $regex ]]; then
  major="${BASH_REMATCH[1]}"
  minor="${BASH_REMATCH[2]}"
  patch="${BASH_REMATCH[3]}"
fi

if ((major < required_major)) || ((minor < required_minor)) || ((patch < required_patch)); then
  echo "$utility $required_major.$required_minor.$required_patch required, but is $major.$minor.$patch"
  exit 1
fi

help() {
  echo "Usage: $0 [OPTION]..."
  echo "Formats source code in the repository, applying formatting in place by default"
  echo ""
  echo "-h, --help        Print Help"
  echo "-d, --dry-run     Dry run formatters, returning 0 when code passes, 1 otherwise"
  echo ""
  echo "Exit status:"
  echo "0 if code required no formatting"
  echo "non-zero exit status otherwise"
}

dry_run() {
  find runtime \
    \( -path "runtime/thirdparty" -o -path "runtime/tests/gocr" -o -path "runtime/tests/TinyEKF" -o -path "runtime/tests/CMSIS_5_NN" -o -path "runtime/tests/sod" -o -path "runtime/tests/**/thirdparty" \) -prune -false -o \
    -type f \( -iname \*.h -o -iname \*.c -o -iname \*.s \) -print |
    xargs clang-format -Werror -n -ferror-limit=0
}

format() {
  find runtime \
    \( -path "runtime/thirdparty" -o -path "runtime/tests/gocr" -o -path "runtime/tests/TinyEKF" -o -path "runtime/tests/CMSIS_5_NN" -o -path "runtime/tests/sod" -o -path "runtime/tests/**/thirdparty" \) -prune -false -o \
    -type f \( -iname \*.h -o -iname \*.c -o -iname \*.s \) -print |
    xargs clang-format -i
}

case $1 in
  "-h" | "--help") help ;;
  "-d" | "--dry-run") dry_run ;;
  "") format ;;
esac