#!/usr/bin/env bash
# Clones or updates the repo to WORKSPACE_DIR/<repo-name> and checks out the
# target commit. Sets REPO_DIR in $GITHUB_ENV on success.
#
# Required env vars (provided by GitHub Actions context):
#   WORKSPACE_DIR, GITHUB_SERVER_URL, GITHUB_REPOSITORY, github.sha,
#   github.ref, github.ref_name, github.event.repository.name
# Optional:
#   WORKFLOW secret (used as OAuth token for private repos)
set -euo pipefail

REPO_NAME="${REPO_NAME}"
REPO_DIR="${WORKSPACE_DIR}/${REPO_NAME}"
TOKEN="${TOKEN:-}"

if [ -n "$TOKEN" ]; then
  REPO_URL="https://oauth2:${TOKEN}@${GITHUB_SERVER_URL#https://}/${GITHUB_REPOSITORY}.git"
else
  REPO_URL="${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}.git"
fi

if [ -d "$REPO_DIR" ]; then
  if [ -d "$REPO_DIR/.git" ]; then
    cd "$REPO_DIR"
    git clean -fdx
    git reset --hard
    git fetch --all --tags --force --prune --prune-tags
  else
    rm -rf "$REPO_DIR"
  fi
fi

if [ ! -d "$REPO_DIR/.git" ]; then
  mkdir -p "$WORKSPACE_DIR"
  git clone "$REPO_URL" "$REPO_DIR"
  cd "$REPO_DIR"
fi

if git -C "$REPO_DIR" cat-file -e "${TARGET_SHA}^{commit}" 2>/dev/null; then
  git -C "$REPO_DIR" checkout -f "$TARGET_SHA"
else
  if [ -n "${TARGET_REF:-}" ]; then
    git -C "$REPO_DIR" fetch origin "$TARGET_REF"
    git -C "$REPO_DIR" checkout -f FETCH_HEAD
  else
    git -C "$REPO_DIR" checkout -f "$TARGET_REF_NAME"
  fi
fi

git config --global --add safe.directory "$REPO_DIR"
echo "REPO_DIR=$REPO_DIR" >> "$GITHUB_ENV"