#!/bin/bash
# Verify an RFS flist manifest: inspect, tree, and optional mount test (best-effort)
# This script is safe to run on developer machines; mount test may require root and FUSE policy.

set -euo pipefail

HERE="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# shellcheck source=/dev/null
source "${HERE}/common.sh"

usage() {
  cat <<'EOF'
Usage: scripts/rfs/verify-flist.sh -m path/to/manifest.fl [--tree] [--mount] [--mountpoint DIR]

Actions:
  - Inspect manifest metadata (always)
  - Tree view of entries (--tree)
  - Optional mount test (--mount) to a temporary or given mountpoint

Notes:
  - Mount test typically requires root and proper FUSE configuration.
  - On success, a quick directory listing is shown, then the mount is unmounted.
EOF
}

section() { echo -e "\n==== $* ====\n"; }

MANIFEST=""
DO_TREE=0
DO_MOUNT=0
MOUNTPOINT=""

# Parse args
if [[ $# -eq 0 ]]; then
  usage
  exit 1
fi

while [[ $# -gt 0 ]]; do
  case "$1" in
    -m|--manifest)
      MANIFEST="${2:-}"; shift 2;;
    --tree)
      DO_TREE=1; shift;;
    --mount)
      DO_MOUNT=1; shift;;
    --mountpoint)
      MOUNTPOINT="${2:-}"; shift 2;;
    -h|--help)
      usage; exit 0;;
    *)
      echo "Unknown argument: $1" >&2; usage; exit 1;;
  esac
done

if [[ -z "${MANIFEST}" || ! -f "${MANIFEST}" ]]; then
  log_error "Manifest not found: ${MANIFEST:-<empty>}"
  exit 1
fi

# Ensure rfs binary is available
rfs_common_locate_rfs

section "Inspecting manifest"
safe_execute "${RFS_BIN}" flist inspect -m "${MANIFEST}" || {
  log_warn "rfs flist inspect failed (old rfs?)"
  log_warn "Try: ${RFS_BIN} inspect ${MANIFEST}"
}

if [[ ${DO_TREE} -eq 1 ]]; then
  section "Listing manifest tree"
  safe_execute "${RFS_BIN}" flist tree -m "${MANIFEST}" 2>/dev/null || {
    log_warn "rfs flist tree failed; attempting fallback 'tree'"
    safe_execute "${RFS_BIN}" tree -m "${MANIFEST}" || true
  }
fi

if [[ ${DO_MOUNT} -eq 1 ]]; then
  section "Mount test"
  if [[ "$(id -u)" -ne 0 ]]; then
    log_warn "Mount test skipped: requires root (uid 0)"
  else
    # Decide mountpoint
    local_mp_created=0
    if [[ -z "${MOUNTPOINT}" ]]; then
      MOUNTPOINT="$(mktemp -d /tmp/rfs-mnt.XXXXXX)"
      local_mp_created=1
    else
      mkdir -p "${MOUNTPOINT}"
    fi
    log_info "Mounting ${MANIFEST} -> ${MOUNTPOINT}"
    set +e
    # Best-effort background mount
    (setsid "${RFS_BIN}" mount -m "${MANIFEST}" "${MOUNTPOINT}" >/tmp/rfs-mount.log 2>&1) &
    mpid=$!
    sleep 2
    ls -la "${MOUNTPOINT}" | head -n 50 || true
    # Try to unmount and stop background process
    umount "${MOUNTPOINT}" 2>/dev/null || fusermount -u "${MOUNTPOINT}" 2>/dev/null || true
    kill "${mpid}" 2>/dev/null || true
    set -e
    if [[ ${local_mp_created} -eq 1 ]]; then
      rmdir "${MOUNTPOINT}" 2>/dev/null || true
    fi
    log_info "Mount test done (see /tmp/rfs-mount.log if issues)"
  fi
fi

section "Verify complete"
log_info "Manifest: ${MANIFEST}"