#!/usr/bin/env bash
# =============================================================================
# lib/clean-start.sh — single source of truth for the pre-session reset.
# Caller must already be INSIDE the genome checkout.
# Aligns the working tree to origin/<base>. Never force-pushes a shared branch.
# Tolerates a missing remote branch (first-setup scenario).
# NOTE: sourced library — no `set -euo pipefail` (would leak into the caller).
# =============================================================================

clean_start() {
  local base="${INGEST_BASE:-main}"
  git fetch -q origin || return 1
  git switch -q "$base" 2>/dev/null || git checkout -q -b "$base" || return 1
  if git ls-remote --exit-code --heads origin "$base" >/dev/null 2>&1; then
    git reset -q --hard "origin/${base}" || return 1
  fi
  git clean -q -fd || return 1
}