#!/bin/sh
# Boot from a local disk installation

CONFIG_BOOT_GUI_MENU_NAME='Heads Boot Menu'

. /etc/functions
. /etc/config

mount_boot()
{
  # Mount local disk if it is not already mounted
  if ! grep -q /boot /proc/mounts ; then
    mount -o ro /boot \
      || recovery "Unable to mount /boot"
  fi
}


last_half=X
while true; do
  MAIN_MENU_OPTIONS=""
  unset totp_confirm
  # update the TOTP code every thirty seconds
  date=`date "+%Y-%m-%d %H:%M:%S"`
  seconds=`date "+%s"`
  half=`expr \( $seconds % 60 \) / 30`
  if [ "$CONFIG_TPM" = n ]; then
    TOTP="NO TPM"
  elif [ "$half" != "$last_half" ]; then
    last_half=$half;
    TOTP=`unseal-totp`
    if [ $? -ne 0 ]; then
      whiptail --clear --title "ERROR: TOTP Generation Failed!" \
        --menu "ERROR: Heads couldn't generate the TOTP code.\n\nIf you have just reflashed your BIOS, you will need to generate a new TOTP secret.\n\nIf you have not just reflashed your BIOS, THIS COULD INDICATE TAMPERING!\n\nHow would you like to proceed?" 20 60 4 \
        'g' ' Generate new TOTP secret' \
        'i' ' Ignore error and continue to default boot menu' \
        'x' ' Exit to recovery shell' \
        2>/tmp/whiptail || recovery "GUI menu failed"

      totp_confirm=$(cat /tmp/whiptail)
    fi
  fi

  if [ "$totp_confirm" = "i" -o -z "$totp_confirm" ]; then 
    whiptail --clear --title "$CONFIG_BOOT_GUI_MENU_NAME" \
      --menu "$date\nTOTP code: $TOTP" 20 60 8 \
      'y' ' Default boot' \
      'r' ' TOTP does not match, refresh code' \
      'n' ' TOTP does not match after refresh, troubleshoot' \
      'm' ' Show OS boot menu' \
      'u' ' USB boot' \
      'g' ' Generate new TOTP secret' \
      'x' ' Exit to recovery shell' \
      2>/tmp/whiptail || recovery "GUI menu failed"

    totp_confirm=$(cat /tmp/whiptail)
  fi

  if [ "$totp_confirm" = "x" ]; then
    recovery "User requested recovery shell"
  fi

  if [ "$totp_confirm" = "r" ]; then
    continue
  fi

  if [ "$totp_confirm" = "n" ]; then
    if (whiptail --title "TOTP code mismatched" \
      --yesno "TOTP code mismatches could indicate either TPM tampering or clock drift:\n\nTo correct clock drift: 'date -s HH:MM:SS'\nand save it to the RTC: 'hwclock -w'\nthen reboot and try again.\n\nWould you like to exit to a recovery console?" 30 60) then
      echo ""
      echo "To correct clock drift: 'date -s HH:MM:SS'"
      echo "and save it to the RTC: 'hwclock -w'"
      echo "then reboot and try again"
      echo ""
      recovery "TOTP mismatch"
    else
      continue
    fi
  fi

  if [ "$totp_confirm" = "u" ]; then
    exec /bin/usb-init
    continue
  fi

  if [ "$totp_confirm" = "g" ]; then
    if (whiptail --title 'Generate new TOTP secret' \
        --yesno "This will erase your old secret and replace it with a new one!\n\nDo you want to proceed?" 16 60) then
      echo "Scan the QR code to add the new TOTP secret"
      /bin/seal-totp
      echo "Once you have scanned the QR code, hit Enter to reboot"
      read
      /bin/reboot
    else
      echo "Returning to the main menu"
    fi
    continue
  fi

  if [ "$totp_confirm" = "m" ]; then
    # Try to select a kernel from the menu
    mount_boot
    kexec-select-boot -m -b /boot -c "grub.cfg" -g
    continue
  fi

  if [ "$totp_confirm" = "y" -o -n "$totp_confirm" ]; then
    # Try to boot the default
    mount_boot
	  DEFAULT_FILE=`find /boot/kexec_default.*.txt 2>/dev/null | head -1`
    if [ -r "$DEFAULT_FILE" ]; then
      kexec-select-boot -b /boot -c "grub.cfg" \
      || recovery "Failed default boot"
    else
      if (whiptail --title 'No Default Boot Option Configured' \
          --yesno "There is no default boot option configured yet. Would you like to load a menu of boot options? Otherwise you will return to the main menu." 16 60) then
        kexec-select-boot -m -b /boot -c "grub.cfg" -g
      else
        echo "Returning to the main menu"
      fi
      continue
    fi
  fi

done

recovery "Something failed during boot"