set -x # verbose mode

set -e # stop executing after error

echo "Starting Jekyll diff script"

mkdir /jekyll-diff-action

mkdir /jekyll-diff-action/new

mkdir /jekyll-diff-action/old

mkdir /jekyll-diff-action/workspace

cp --archive /github/workspace/. /jekyll-diff-action/workspace

chmod -R a+w /jekyll-diff-action

cd /jekyll-diff-action/workspace

if [ "$GITHUB_EVENT_NAME" = "pull_request" ]; then

echo "PR mode"

common_ancestor_sha="$(git merge-base $GITHUB_SHA origin/$GITHUB_BASE_REF)" # find the closest common ancestor between the PR branch and the target branch

api_url="$(cat $GITHUB_EVENT_PATH | jq --raw-output '.pull_request.comments_url')"

echo "Commit mode"

common_ancestor_sha="$(git rev-parse HEAD^1)"

api_url="https://api.github.com/repos/${GITHUB_REPOSITORY}/commits/${GITHUB_SHA}/comments"

jekyll build --trace --destination /jekyll-diff-action/new

git checkout --force $common_ancestor_sha

jekyll build --trace --destination /jekyll-diff-action/old

diff="$(diff --recursive --new-file --unified=0 /jekyll-diff-action/old /jekyll-diff-action/new || true)" # 'or true' because a non-identical diff outputs 1 as the exit status

comment="\`\`\`diff

curl --include --verbose --fail \

-H "Accept: application/json" \

-H "Content-Type:application/json" \

-H "Authorization: token ${GITHUB_TOKEN}" \

--request POST --data "$(jq --null-input --arg escaped_diff "$comment" '{body: $escaped_diff}')" \

echo "Done"