#!/bin/bash
# Copyright 2017 The Fuchsia Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

### make a zedboot USB key

## usage: fx mkzedboot [options] <usb device>
##  -f  force writing to a non-usb target

set -e

source "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"/lib/image_build_vars.sh

force=false
if [[ "$1" == "-f" ]]; then
  shift
  force=true
fi

is_usb() {
  if ! ${force}; then
    fx-command-run list-usb-disks | grep "$1"
  fi
}

USB_DEVICE="$1"
if [[ -z "${USB_DEVICE}" ]]; then
  echo >&2 "device argument required"
  echo "USB disks:"
  fx-command-run list-usb-disks
  exit 1
fi
if ! is_usb "${USB_DEVICE}"; then
  echo >&2 "${USB_DEVICE} does not look like a USB device, use -f to force, or pick from below"
  echo "USB disks:"
  fx-command-run list-usb-disks
  exit 1
fi

echo >&2 "Changing ownership of ${USB_DEVICE} to ${USER}"
sudo chown "${USER}" "${USB_DEVICE}"

# Linux doesn't automount things aggressively, so no work to do.
unmountcmd=""
# MacOS is really persistent about remounting disks after the raw block device
# is closed, so, keep doing this. In the future we will replace CGPT with our
# own tool that can do everything in one shot, like make-fuchsia-vol does. The
# hack here keeps an open reference to the disk device, which prevents
# re-initialization of the gpt driver.
if [[ "$(uname)" == "Darwin" ]]; then
  echo
  echo "### NOTE:"
  echo "### NOTE: Click 'ignore' on any MacOS disk dialog boxes"
  echo "### NOTE:"
  echo

  unmountcmd="diskutil quiet unmountDisk ${USB_DEVICE}"
fi

# Destroy any existing GPT/MBR on the device and re-create
echo "Create new GPT partition table... "
$unmountcmd
"${FUCHSIA_BUILD_DIR}/tools/cgpt" create "${USB_DEVICE}"
$unmountcmd
"${FUCHSIA_BUILD_DIR}/tools/cgpt" boot -p "${USB_DEVICE}"
$unmountcmd
echo "done"

echo "Create new partitions... "
# ESP needs to be a FAT compatible size
esp_size=$(((63*1024*1024)/512))
vboot_size=$(((64*1024*1024)/512))
esp_offset=2048
vboot_offset=$(($esp_size + $esp_offset))
$unmountcmd
"${FUCHSIA_BUILD_DIR}/tools/cgpt" add -s "${esp_size}" -t efi -b "${esp_offset}" -l esp "${USB_DEVICE}"
$unmountcmd
"${FUCHSIA_BUILD_DIR}/tools/cgpt" add -s "${vboot_size}" -t kernel -b "${vboot_offset}" -l zedboot "${USB_DEVICE}"
$unmountcmd
"${FUCHSIA_BUILD_DIR}/tools/cgpt" add -i 2 -T 1 -S 1 -P 2 "${USB_DEVICE}"
echo "done"

echo "Building zedboot partitions..."
fx-command-run build "images/zedboot-${ZIRCON_PROJECT}.vboot" "images/zedboot-${ZIRCON_PROJECT}.esp.blk"
echo "done"

echo "Writing zedboot for EFI"
$unmountcmd
dd if="${FUCHSIA_BUILD_DIR}/images/zedboot-${ZIRCON_PROJECT}.esp.blk" of="${USB_DEVICE}" seek=${esp_offset}
echo "Writing zedboot for Cros"
$unmountcmd
dd if="${FUCHSIA_BUILD_DIR}/images/zedboot-${ZIRCON_PROJECT}.vboot" of="${USB_DEVICE}" seek=${vboot_offset}
echo "done"

case "$(uname)" in
  Linux)
    eject "${USB_DEVICE}"
    ;;
  Darwin)
    diskutil eject "${USB_DEVICE}"
    ;;
esac