#!/usr/bin/env bash
set -euo pipefail

usage() {
  cat <<'EOF'
usage: scripts/worktree-clean [--dry-run] [--delete-branch] <branch-name|folder-name>

Remove a branch worktree under branches/ AFTER its PR is merged or closed. This
is the ONLY helper that deletes anything, and it deletes nothing unless you
invoke it explicitly. It refuses to remove a worktree with uncommitted changes
(no --force is offered). With --delete-branch it also deletes the local branch,
but only with a safe `git branch -d` (fails unless the branch is merged).

Pass the branch name (with slashes) so --delete-branch can resolve it; the
folder is branches/<branch-with-slashes-replaced-by-dashes>.

Examples:
  scripts/worktree-clean --dry-run fix/issue-123-example
  scripts/worktree-clean --delete-branch fix/issue-123-example
EOF
}

dry_run=0
del_branch=0
while [[ "${1:-}" == --* ]]; do
  case "$1" in
    --dry-run) dry_run=1 ;;
    --delete-branch) del_branch=1 ;;
    --help) usage; exit 0 ;;
    *) usage >&2; exit 2 ;;
  esac
  shift
done

if [[ $# -ne 1 ]]; then
  usage >&2
  exit 2
fi

branch="$1"
worktree_name="${branch//\//-}"

script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
repo_root="$(cd "$script_dir/.." && pwd)"
worktree_path="$repo_root/branches/$worktree_name"

if [[ ! -d "$worktree_path" ]]; then
  printf 'No such worktree: %s\n' "$worktree_path" >&2
  exit 1
fi

if [[ "$dry_run" -eq 1 ]]; then
  printf 'repo: %s\n' "$repo_root"
  printf 'worktree: %s\n' "$worktree_path"
  printf 'delete-branch: %s\n' "$del_branch"
  printf 'commands:\n'
  printf '  git -C %q fetch prgs --prune\n' "$repo_root"
  printf '  git -C %q worktree remove %q\n' "$repo_root" "$worktree_path"
  if [[ "$del_branch" -eq 1 ]]; then
    printf '  git -C %q branch -d %q\n' "$repo_root" "$branch"
  fi
  exit 0
fi

git -C "$repo_root" fetch prgs --prune
# No --force: `git worktree remove` fails on uncommitted changes, on purpose.
git -C "$repo_root" worktree remove "$worktree_path"
printf 'removed worktree: %s\n' "$worktree_path"

if [[ "$del_branch" -eq 1 ]]; then
  # Safe delete only: refuses to drop an unmerged branch.
  git -C "$repo_root" branch -d "$branch"
  printf 'deleted branch: %s\n' "$branch"
fi