#!/usr/bin/env bash
# sync_upstream_knoe_db.sh — Pull upstream knoe-db changes into a review branch.
#
# Usage:
#   ./scripts/sync_upstream_knoe_db.sh [--dry-run]
#
# What it does:
#   1. Ensures the 'upstream-knoe-db' remote points to git@git.knoe.dev:knoe-dev/knoe-db.git
#   2. Fetches the upstream default branch
#   3. Creates a timestamped branch  upstream/knoe-db/YYYYMMDD  from the fetch
#   4. Prints next steps for review and merge
#
# Run from the knoe-db/ subdirectory or the repo root (script auto-detects).

set -euo pipefail

UPSTREAM_REMOTE="upstream-knoe-db"
UPSTREAM_URL="git@git.knoe.dev:knoe-dev/knoe-db.git"
UPSTREAM_BRANCH="main"          # adjust if upstream uses a different default branch
DATE_TAG="$(date +%Y%m%d)"
REVIEW_BRANCH="upstream/knoe-db/${DATE_TAG}"
DRY_RUN=false

# ── argument parsing ──────────────────────────────────────────────────────────
for arg in "$@"; do
  case "$arg" in
    --dry-run) DRY_RUN=true ;;
    *) echo "Unknown argument: $arg" >&2; exit 1 ;;
  esac
done

run() {
  if $DRY_RUN; then
    echo "[dry-run] $*"
  else
    "$@"
  fi
}

# ── locate the knoe-db git worktree ───────────────────────────────────────────
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
REPO_ROOT="$(cd "${SCRIPT_DIR}/.." && pwd)"
KNOE_DB_DIR="${REPO_ROOT}/knoe-db"

if [ ! -d "${KNOE_DB_DIR}/.git" ] && [ ! -f "${KNOE_DB_DIR}/.git" ]; then
  # knoe-db may be a plain directory inside a mono-repo; operate from repo root
  GIT_DIR="${REPO_ROOT}"
else
  GIT_DIR="${KNOE_DB_DIR}"
fi

echo "==> Working in git repo: ${GIT_DIR}"
cd "${GIT_DIR}"

# ── ensure we are on a clean working tree ────────────────────────────────────
if ! $DRY_RUN; then
  if ! git diff --quiet || ! git diff --cached --quiet; then
    echo "ERROR: Working tree has uncommitted changes. Stash or commit before syncing." >&2
    exit 1
  fi
fi

# ── add / verify upstream remote ─────────────────────────────────────────────
if git remote get-url "${UPSTREAM_REMOTE}" &>/dev/null; then
  CURRENT_URL="$(git remote get-url "${UPSTREAM_REMOTE}")"
  if [ "${CURRENT_URL}" != "${UPSTREAM_URL}" ]; then
    echo "==> Updating remote '${UPSTREAM_REMOTE}' URL to ${UPSTREAM_URL}"
    run git remote set-url "${UPSTREAM_REMOTE}" "${UPSTREAM_URL}"
  else
    echo "==> Remote '${UPSTREAM_REMOTE}' already set to ${UPSTREAM_URL}"
  fi
else
  echo "==> Adding remote '${UPSTREAM_REMOTE}' → ${UPSTREAM_URL}"
  run git remote add "${UPSTREAM_REMOTE}" "${UPSTREAM_URL}"
fi

# ── fetch upstream ────────────────────────────────────────────────────────────
echo "==> Fetching ${UPSTREAM_REMOTE}/${UPSTREAM_BRANCH} …"
run git fetch "${UPSTREAM_REMOTE}" "${UPSTREAM_BRANCH}"

# ── create review branch ──────────────────────────────────────────────────────
if git show-ref --verify --quiet "refs/heads/${REVIEW_BRANCH}"; then
  echo "==> Branch '${REVIEW_BRANCH}' already exists — skipping creation."
  echo "    Delete it first if you want a fresh sync:  git branch -D ${REVIEW_BRANCH}"
else
  echo "==> Creating review branch '${REVIEW_BRANCH}' from ${UPSTREAM_REMOTE}/${UPSTREAM_BRANCH}"
  run git checkout -b "${REVIEW_BRANCH}" "${UPSTREAM_REMOTE}/${UPSTREAM_BRANCH}"
  run git checkout -        # return to previous branch
fi

# ── summary ───────────────────────────────────────────────────────────────────
echo ""
echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
echo "  Upstream sync complete."
echo ""
echo "  Review branch : ${REVIEW_BRANCH}"
echo "  Upstream      : ${UPSTREAM_URL} (${UPSTREAM_BRANCH})"
echo ""
echo "  Next steps:"
echo "    1. Inspect the incoming changes:"
echo "       git log main..${REVIEW_BRANCH} --oneline"
echo "       git diff main...${REVIEW_BRANCH} -- knoe-db/"
echo ""
echo "    2. Check out the review branch and resolve any conflicts:"
echo "       git checkout ${REVIEW_BRANCH}"
echo ""
echo "    3. Merge (or cherry-pick) into main when satisfied:"
echo "       git checkout main"
echo "       git merge --no-ff ${REVIEW_BRANCH} -m 'chore(knoe-db): merge upstream ${DATE_TAG}'"
echo ""
echo "    4. Push and open a PR / MR for team review."
echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"