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

SCRIPT_DIR=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)
LIB_DIR=${SCRIPT_DIR}/lib

# shellcheck source=lib/common.sh
source "${LIB_DIR}/common.sh"

on_error() {
  local exit_code=$1
  local line_no=$2
  log_err "脚本在第 ${line_no} 行发生错误，退出码 ${exit_code}。"
  exit "${exit_code}"
}
trap 'on_error "$?" "$LINENO"' ERR

# shellcheck source=lib/storage.sh
source "${LIB_DIR}/storage.sh"
# shellcheck source=lib/persist.sh
source "${LIB_DIR}/persist.sh"
# shellcheck source=lib/iptables_ops.sh
source "${LIB_DIR}/iptables_ops.sh"
# shellcheck source=lib/env_check.sh
source "${LIB_DIR}/env_check.sh"
# shellcheck source=lib/rules_mgr.sh
source "${LIB_DIR}/rules_mgr.sh"

: "${IPF_SKIP_ENV_CHECK:=0}"

usage() {
  cat <<USAGE
用法:
  ./iptables-forward.sh
  ./iptables-forward.sh --batch add <proto> <listen_port> <target_ip> <target_port> <ipver> [desc]
  ./iptables-forward.sh --batch delete <uuid>
  ./iptables-forward.sh --batch list
  ./iptables-forward.sh --batch save
  ./iptables-forward.sh --batch env
  ./iptables-forward.sh --help

说明:
  - proto: tcp / udp / both
  - ipver: 4 / 6 / both
  - 当 ipver=both 时，target_ip 需使用 IPv4,IPv6 形式，例如 127.0.0.1,::1
USAGE
}

bootstrap() {
  if [[ ${IPF_SKIP_ENV_CHECK} != 1 ]]; then
    env_check_all
  fi
  storage_init
}

render_main_menu() {
  local status persist count width
  status=$(env_status_summary)
  count=$(storage_count)
  if persist_available; then
    persist='[✓]'
  else
    persist='[!]'
  fi

  if use_box_ui; then
    width=$(term_width)
    if (( width > 78 )); then
      width=78
    fi
    box_top "${width}"
    box_line "${width}" "${IPF_APP_NAME}"
    box_separator "${width}"
    box_line "${width}" "状态: ${status}    规则数: ${count}    持久化: ${persist}"
    box_separator "${width}"
    box_line "${width}" '[1] 查看所有转发规则'
    box_line "${width}" '[2] 添加新的转发规则'
    box_line "${width}" '[3] 删除现有转发规则'
    box_line "${width}" '[4] 查看系统环境状态'
    box_line "${width}" '[5] 立即保存到磁盘'
    box_line "${width}" '[0] 退出'
    box_bottom "${width}"
  else
    printf '%s\n' "${IPF_APP_NAME}"
    printf '状态: %s | 规则数: %s | 持久化: %s\n' "${status}" "${count}" "${persist}"
    printf '[1] 查看所有转发规则\n'
    printf '[2] 添加新的转发规则\n'
    printf '[3] 删除现有转发规则\n'
    printf '[4] 查看系统环境状态\n'
    printf '[5] 立即保存到磁盘\n'
    printf '[0] 退出\n'
  fi
}

main_menu_loop() {
  local choice
  while true; do
    render_main_menu
    choice=$(prompt_input '请选择 [0-5]' '')
    case ${choice} in
      1) cmd_list ;;
      2) cmd_add ;;
      3) cmd_delete ;;
      4) cmd_show_env_status ;;
      5)
        cmd_save_rules
        pause_return
        ;;
      0)
        log_info '已退出。'
        return 0
        ;;
      *)
        log_warn '无效选择，请输入 0-5。'
        ;;
    esac
  done
}

run_batch() {
  local action=${1-}
  shift || true
  case ${action} in
    add)
      if (($# < 5)); then
        usage
        return 1
      fi
      cmd_add_batch "$@"
      ;;
    delete)
      if (($# != 1)); then
        usage
        return 1
      fi
      cmd_delete_uuid "$1"
      ;;
    list)
      storage_list
      ;;
    save)
      cmd_save_rules
      ;;
    env)
      env_check_all
      ;;
    *)
      usage
      return 1
      ;;
  esac
}

main() {
  case ${1-} in
    --help|-h)
      usage
      return 0
      ;;
  esac

  require_root || return $?
  bootstrap

  if (($# == 0)); then
    main_menu_loop
    return 0
  fi

  case ${1-} in
    --batch)
      shift
      run_batch "$@"
      ;;
    *)
      usage
      return 1
      ;;
  esac
}

main "$@"