#!/usr/bin/env bash
# SessionStart hook: refuse to let a severed dotfiles link go unnoticed.
#
# Claude Code writes settings with an atomic temp+rename. Through the stow layer that can
# replace ~/.config/claude/<file> (a symlink into the repo) with a plain FILE holding whatever
# snapshot the writing process had in memory -- silently freezing every later repo edit out
# of the live config. It happened on 2026-09-15 23:31: a stale copy dropped four hook events
# (git-guard among them) and nobody noticed for an hour. link.sh heals the identical case but
# only when run; this makes every session start say so instead.
#
# Read-only: it never relinks. Exit 2 on SessionStart shows stderr to the user and the session
# continues. Exit 0 when everything resolves into the repo.
set -u
src="$HOME/.config/claude"
bad=""
for f in settings.json statusline.py keybindings.json CLAUDE.md link.sh; do
  p="$src/$f"
  [ -e "$p" ] || continue
  if [ ! -L "$p" ]; then bad="$bad  $p is a plain file (should be a symlink into the dots repo)"$'\n'; fi
done
# the ~/.claude side too: link.sh's own guard covers it, but only when link.sh runs
for f in settings.json keybindings.json CLAUDE.md statusline.py; do
  p="$HOME/.claude/$f"
  [ -e "$p" ] || continue
  case "$(readlink -f "$p")" in
    *"/.dots/"*) ;;
    *) bad="$bad  $p resolves to $(readlink -f "$p"), not into the dots repo"$'\n' ;;
  esac
done
[ -z "$bad" ] && exit 0
printf 'DRIFT: Claude config has broken out of the dots repo; the live config is a stale copy.\n%s  fix: review with `diff`, then `bash ~/.config/claude/link.sh` (heals identical copies, warns otherwise)\n' "$bad" >&2
exit 2