#!/usr/bin/env bash

# This script runs black on all Python files in the repo.

set -uo pipefail

# Apply black.
echo -e "Formatting Python files..."
PY_FILES=$(git ls-files -- '*SConstruct' '*SCsub' '*.py' ':!:.git/*' ':!:thirdparty/*')
black -l 120 $PY_FILES

diff=$(git diff --color)

# If no diff has been generated all is OK, clean up, and exit.
if [ -z "$diff" ] ; then
    printf "\e[1;32m*** Files in this commit comply with the black style rules.\e[0m\n"
    exit 0
fi

# A diff has been created, notify the user, clean up, and exit.
printf "\n\e[1;33m*** The following changes must be made to comply with the formatting rules:\e[0m\n\n"
# Perl commands replace trailing spaces with `·` and tabs with `<TAB>`.
printf "%s\n" "$diff" | perl -pe 's/(.*[^ ])( +)(\e\[m)$/my $spaces="·" x length($2); sprintf("$1$spaces$3")/ge' | perl -pe 's/(.*[^\t])(\t+)(\e\[m)$/my $tabs="<TAB>" x length($2); sprintf("$1$tabs$3")/ge'

printf "\n\e[1;91m*** Please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\e[0m\n"
exit 1