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

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# shellcheck disable=SC1091
source "${SCRIPT_DIR}/common.sh"

STEP="5g-dial"

run_dial() {
  local rc

  export TERM="${TERM:-xterm}"
  export LANG="${LANG:-C.UTF-8}"
  export LC_ALL="${LC_ALL:-C.UTF-8}"

  blitz_log "${STEP}" "dial-env" "start" "TERM=${TERM} LANG=${LANG} LC_ALL=${LC_ALL} interface=${BLITZ_5G_INTERFACE}" 0

  if blitz_run "${STEP}" "dial" python3 rndis_dial.py --serial-port "${BLITZ_5G_SERIAL_PORT}" --interface "${BLITZ_5G_INTERFACE}"; then
    return 0
  fi

  rc=$?
  blitz_log "${STEP}" "dial-retry" "start" "first dial attempt failed rc=${rc}; retrying after 3s" "${rc}"
  sleep 3
  blitz_run "${STEP}" "dial-retry" python3 rndis_dial.py --serial-port "${BLITZ_5G_SERIAL_PORT}" --interface "${BLITZ_5G_INTERFACE}"
}

wait_for_serial() {
  local serial_port="$1"
  local timeout_sec="$2"
  local waited=0

  while (( waited < timeout_sec )); do
    if [[ -e "${serial_port}" ]]; then
      blitz_log "${STEP}" "wait-serial" "success" "serial_port=${serial_port} waited_sec=${waited}" 0
      return 0
    fi
    if (( waited == 0 || waited % 5 == 0 )); then
      blitz_log "${STEP}" "wait-serial" "waiting" "serial_port=${serial_port} waited_sec=${waited}" 0
    fi
    sleep 1
    waited=$(( waited + 1 ))
  done

  blitz_log "${STEP}" "wait-serial" "failure" "serial_port=${serial_port} timeout_sec=${timeout_sec}" 1
  return 1
}

wait_for_route() {
  local target_ip="$1"
  local timeout_sec="$2"
  local expected_interface="${3:-}"
  local waited=0
  local route_output

  while (( waited < timeout_sec )); do
    route_output="$(blitz_route_ready "${target_ip}" "${expected_interface}" || true)"
    if [[ -n "${route_output}" ]]; then
      blitz_log "${STEP}" "route-check" "success" "target_ip=${target_ip} interface=${expected_interface:-auto} route=${route_output}" 0
      return 0
    fi
    if (( waited == 0 || waited % 5 == 0 )); then
      blitz_log "${STEP}" "route-check" "waiting" "target_ip=${target_ip} interface=${expected_interface:-auto} waited_sec=${waited}" 0
    fi
    sleep 1
    waited=$(( waited + 1 ))
  done

  blitz_log "${STEP}" "route-check" "failure" "target_ip=${target_ip} interface=${expected_interface:-auto} timeout_sec=${timeout_sec}" 1
  return 1
}

blitz_load_boot_env
blitz_require_root "${STEP}"
blitz_require_command ip "${STEP}"
blitz_require_command python3 "${STEP}"
blitz_require_file "${BLITZ_5G_DIAL_DIR}/rndis_dial.py" "${STEP}"

if [[ -z "${BLITZ_TIME_SERVER_IP}" ]]; then
  blitz_log "${STEP}" "precheck" "failure" "BLITZ_TIME_SERVER_IP is empty and no fallback could be derived" 1
  exit 1
fi
if [[ -z "${BLITZ_5G_INTERFACE:-}" ]]; then
  blitz_log "${STEP}" "precheck" "failure" "BLITZ_5G_INTERFACE must not be empty" 1
  exit 1
fi

route_output="$(blitz_route_ready "${BLITZ_TIME_SERVER_IP}" "${BLITZ_5G_INTERFACE}" || true)"
if [[ -n "${route_output}" ]]; then
  blitz_log "${STEP}" "dial" "already_up" "target_ip=${BLITZ_TIME_SERVER_IP} interface=${BLITZ_5G_INTERFACE} route=${route_output}" 0
  exit 0
fi

wait_for_serial "${BLITZ_5G_SERIAL_PORT}" "${BLITZ_5G_SERIAL_WAIT_SEC}"

pushd "${BLITZ_5G_DIAL_DIR}" >/dev/null
run_dial
popd >/dev/null

wait_for_route "${BLITZ_TIME_SERVER_IP}" "${BLITZ_5G_ROUTE_WAIT_SEC}" "${BLITZ_5G_INTERFACE}"
blitz_log "${STEP}" "complete" "success" "5G dial completed and route is ready on ${BLITZ_5G_INTERFACE}" 0