#!/usr/bin/env bash

set -euo pipefail

ROOT_DIR="$(git rev-parse --show-toplevel 2>/dev/null || pwd)"
RUN_NODE_TOOL="$ROOT_DIR/scripts/pre-commit/run-node-tool.sh"
FILTER_FILES="$ROOT_DIR/scripts/pre-commit/filter-staged-files.mjs"

if [[ ! -x "$RUN_NODE_TOOL" ]]; then
  echo "Missing helper: $RUN_NODE_TOOL" >&2
  exit 1
fi

if [[ ! -f "$FILTER_FILES" ]]; then
  echo "Missing helper: $FILTER_FILES" >&2
  exit 1
fi

GIT_DIR="$(git rev-parse --git-dir 2>/dev/null || true)"
if [[ -n "$GIT_DIR" ]] && \
  { [[ -f "$GIT_DIR/MERGE_HEAD" ]] || \
    [[ -f "$GIT_DIR/CHERRY_PICK_HEAD" ]] || \
    [[ -f "$GIT_DIR/REVERT_HEAD" ]] || \
    [[ -f "$GIT_DIR/REBASE_HEAD" ]] || \
    [[ -d "$GIT_DIR/rebase-merge" ]] || \
    [[ -d "$GIT_DIR/rebase-apply" ]]; }; then
  # Sequencer commits stage the operation result, not just the user's local edits.
  exit 0
fi

# Security: avoid option-injection from malicious file names (e.g. "--all", "--force").
# Robustness: NUL-delimited file list handles spaces/newlines safely.
# Compatibility: use read loops instead of `mapfile` so this runs on macOS Bash 3.x.
files=()
while IFS= read -r -d '' file; do
  files+=("$file")
done < <(git diff --cached --name-only --diff-filter=ACMR -z)

if [ "${#files[@]}" -eq 0 ]; then
  exit 0
fi

restage_files=()
for file in "${files[@]}"; do
  if ! git check-ignore --no-index -q -- "$file"; then
    restage_files+=("$file")
  fi
done

format_files=()
while IFS= read -r -d '' file; do
  format_files+=("$file")
done < <(node "$FILTER_FILES" format -- "${restage_files[@]}")

if [ "${#format_files[@]}" -gt 0 ]; then
  "$RUN_NODE_TOOL" oxfmt --write --no-error-on-unmatched-pattern "${format_files[@]}"
fi

if [ "${#restage_files[@]}" -gt 0 ]; then
  git add -- "${restage_files[@]}"
fi