#!/bin/bash

exec 1>&2

# paths to check and re-format
sources="src unittests"
formatter="clang-format -i"
version=$($formatter --version | grep -o '[0-9\.]*')

if [[ "17.0.0" > "$version" ]]; then
    cat <<EOF

                                    ERROR
-----------------------------------------------------------------------------
            A minimum of version 17 of `which clang-format` is required.
            Your version is $version.
            Please fix paths and run again.
-----------------------------------------------------------------------------

EOF
    exit 3
fi

# check there is no .h headers, only .hpp
wrong_headers=$(find $sources -name "*.h" | sed 's/^/        - /')
if [[ ! -z "$wrong_headers" ]]; then
    cat <<EOF

                                    ERROR
-----------------------------------------------------------------------------
       Found .h headers in the source code. Please rename them to .hpp:

$wrong_headers
-----------------------------------------------------------------------------

EOF
    exit 2
fi

function grep_code {
    grep -l "${1}" ${sources} -r --include \*.hpp --include \*.cpp
}

if [[ "$OSTYPE" == "darwin"* ]]; then
    # make all includes to be <...> style
    grep_code '#include ".*"' | xargs sed -i '' -E 's|#include "(.*)"|#include <\1>|g'

    # make local includes to be "..." style
    main_src_dirs=$(find ./src -maxdepth 1 -type d -exec basename {} \; | tr '\n' '|' | sed 's/|$//' | sed 's/|/\\|/g')
    grep_code "#include <\($main_src_dirs\)/.*>" | xargs sed -i '' -E "s|#include <(($main_src_dirs)/.*)>|#include \"\1\"|g"
else
    # make all includes to be <...> style
    grep_code '#include ".*"' | xargs sed -i -E 's|#include "(.*)"|#include <\1>|g'

    # make local includes to be "..." style
    main_src_dirs=$(find ./src -type d -maxdepth 1 -exec basename {} \; | paste -sd '|' | sed 's/|/\\|/g')
    grep_code "#include <\($main_src_dirs\)/.*>" | xargs sed -i -E "s|#include <(($main_src_dirs)/.*)>|#include \"\1\"|g"
fi

first=$(git diff $sources)
find $sources -type f \( -name '*.cpp' -o -name '*.hpp' -o -name '*.ipp' \) -print0 | xargs -0 $formatter
second=$(git diff $sources)
changes=$(diff <(echo "$first") <(echo "$second") | wc -l | sed -e 's/^[[:space:]]*//')

if [ "$changes" != "0" ]; then
    cat <<\EOF

                                   WARNING
-----------------------------------------------------------------------------
  Automatically re-formatted code with `clang-format` - commit was aborted.
  Please manually add any updated files and commit again.
-----------------------------------------------------------------------------

EOF
    exit 1
fi