#!/bin/bash
# Copyright 2020 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.

set -eu

SCRIPT_SRC_DIR="$(cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd)"

# Fuchsia command common functions.
# shellcheck disable=SC1090
source "${SCRIPT_SRC_DIR}/fuchsia-common.sh" || exit $?

FUCHSIA_IMAGE_WORK_DIR="$(get-fuchsia-sdk-data-dir)"
FUCHSIA_BUCKET="$(get-fuchsia-property bucket)"
if [[ "${FUCHSIA_BUCKET}" == "" ]]; then
  FUCHSIA_BUCKET="${DEFAULT_FUCHSIA_BUCKET}"
fi

FUCHSIA_SERVER_PORT="8083"

IMAGE_NAME="$(get-fuchsia-property image)"
if [[ "${IMAGE_NAME}" == "" ]]; then
  IMAGE_NAME="generic-x64"
fi

SOURCE_NAME="devhost"

usage () {
  echo "Usage: $0"
  echo "  [--work-dir <directory to store image assets>]"
  echo "    Defaults to ${FUCHSIA_IMAGE_WORK_DIR}."
  echo "  [--bucket <fuchsia gsutil bucket>]"
  echo "    Defaults to ${FUCHSIA_BUCKET}."
  echo "  [--image <image name>]"
  echo "    Defaults to ${IMAGE_NAME}. Use --image list to list all available images."
  echo "  [--private-key <identity file>]"
  echo "    Uses additional private key when using ssh to access the device."
  echo "  [--server-port <port>]"
  echo "    Port number to use when serving the packages.  Defaults to ${FUCHSIA_SERVER_PORT}."
  echo "  [--device-name <device hostname>]"
  echo "    Only serves packages to a device with the given device hostname. Cannot be used with --device-ip."
  echo "    If neither --device-name nor --device-ip are specified, the device-name configured using fconfig.sh is used."
  echo "  [--device-ip <device ip>]"
  echo "    Only serves packages to a device with the given device ip address. Cannot be used with --device-name."
  echo "    If neither --device-name nor --device-ip are specified, the device-ip configured using fconfig.sh is used."
  echo "  [--sshconfig <sshconfig file>]"
  echo "    Use the specified sshconfig file instead of fssh's version."
  echo "  [--kill]"
  echo "    Kills any existing package manager server."
  echo "  [--prepare]"
  echo "    Downloads any dependencies but does not start the package server."
  echo "  [-x]"
  echo "    Enable debug."
  echo "  [--name <source name>]"
  echo "    Name for the package server. Defaults to ${SOURCE_NAME}."
  echo "    This name is used as the update channel identifier, as reported by fuchsia.update.channel.Provider."
}

PRIVATE_KEY_FILE=""
PREPARE_ONLY=""
DEVICE_NAME_FILTER=""
DEVICE_IP_ADDR=""
SSHCONFIG_FILE=""

# Parse command line
while (( "$#" )); do
case $1 in
    --work-dir)
      shift
      FUCHSIA_IMAGE_WORK_DIR="${1:-.}"
    ;;
    --bucket)
      shift
      FUCHSIA_BUCKET="${1}"
    ;;
    --image)
      shift
      IMAGE_NAME="${1}"
    ;;
    --private-key)
      shift
      PRIVATE_KEY_FILE="${1}"
    ;;
    --server-port)
      shift
      FUCHSIA_SERVER_PORT="${1}"
    ;;
    --device-name)
      shift
      DEVICE_NAME_FILTER="${1}"
    ;;
    --device-ip)
      shift
      DEVICE_IP_ADDR="${1}"
    ;;
    --sshconfig)
      shift
      SSHCONFIG_FILE="${1}"
    ;;
    --kill)
      kill-running-pm
      exit 0
    ;;
    --prepare)
      PREPARE_ONLY="yes"
    ;;
    -x)
      set -x
    ;;
    --name)
      shift
      SOURCE_NAME="${1}"
    ;;
    *)
      # unknown option
      usage
      exit 1
    ;;
esac
shift
done

if [[ "${DEVICE_IP_ADDR}" == "" && "${DEVICE_NAME_FILTER}" == "" ]]; then
  # No device specified on the command line, so use the default IP, then the
  # default name if configured.
  DEVICE_IP_ADDR="$(get-fuchsia-property device-ip)"
  if [[ -z "${DEVICE_IP_ADDR}" ]]; then
    DEVICE_NAME_FILTER="$(get-fuchsia-property device-name)"
    if [[ -n "${DEVICE_NAME_FILTER}" ]]; then
      echo "Using device name ${DEVICE_NAME_FILTER}. Use --device-name or fconfig.sh to use another device."
    fi
  else
    echo "Using device address ${DEVICE_IP_ADDR}. Use --device-ip or fconfig.sh to use another device."
  fi
elif [[ "${DEVICE_IP_ADDR}" != "" && "${DEVICE_NAME_FILTER}" != "" ]]; then
  fx-error "Cannot use both --device-name and --device-ip".
  exit 1
fi

if ! SDK_ID="$(get-sdk-version)"; then
  fx-error "Could not get SDK version"
  exit 1
fi

if [[ "${IMAGE_NAME}" == "list" ]]; then
  if ! IMAGES="$(get-available-images "${SDK_ID}" "${FUCHSIA_BUCKET}")"; then
    fx-error "Could not get list of available images for ${SDK_ID}"
    exit 1
  fi
  echo "Valid images for this SDK version are: ${IMAGES}."
  exit 1
fi

# The package tarball.  We add the SDK ID to the filename to make them
# unique.
#
# Consider cleaning up old tarballs when getting a new one?
#

FUCHSIA_TARGET_PACKAGES=$(get-package-src-path "${SDK_ID}" "${IMAGE_NAME}")
# The package tarball, we add the SDK ID to make it unique, and note the
# .tar.gz extension for packages vs .tgz extension for images.
IMAGE_FILENAME="${SDK_ID}_${IMAGE_NAME}.tar.gz"

echo "Serving ${IMAGE_NAME} packages for SDK version $(get-sdk-version) from ${FUCHSIA_TARGET_PACKAGES}"

# Validate the image is found
if [[ ! -f "${FUCHSIA_IMAGE_WORK_DIR}/${IMAGE_FILENAME}" ]] ; then
  if ! run-gsutil ls "${FUCHSIA_TARGET_PACKAGES}" >/dev/null 2>&1; then
    echo "Packages for ${IMAGE_NAME} not found. Valid images for this SDK version are:"
    if ! IMAGES="$(get-available-images "${SDK_ID}" "${FUCHSIA_BUCKET}")"; then
      fx-error "Could not get list of available images for ${SDK_ID}"
      exit 1
    fi
    echo "${IMAGES}"
    exit 2
  fi

  if ! run-gsutil cp "${FUCHSIA_TARGET_PACKAGES}" "${FUCHSIA_IMAGE_WORK_DIR}/${IMAGE_FILENAME}"; then
    fx-error "Could not copy image from ${FUCHSIA_TARGET_PACKAGES} to ${FUCHSIA_IMAGE_WORK_DIR}/${IMAGE_FILENAME}."
    exit 2
  fi
else
  echo "Skipping download, packages tarball exists"
fi

# The checksum file contains the output from `md5`. This is used to detect content
# changes in the packages file.
CHECKSUM_FILE="${FUCHSIA_IMAGE_WORK_DIR}/packages/packages.md5"

# check that any existing contents of the image directory match the intended target device
if [[ -f "${CHECKSUM_FILE}" ]]; then
  if [[ "$(run-md5 "${FUCHSIA_IMAGE_WORK_DIR}/${IMAGE_FILENAME}")" != "$(cat "${CHECKSUM_FILE}")" ]]; then
    fx-warn "Removing old package files."
    if ! rm -f "$(cut -d ' '  -f3 "${CHECKSUM_FILE}")"; then
      fx-error "Could not clean up old image archive."
      exit 2
    fi
    if ! rm -rf "${FUCHSIA_IMAGE_WORK_DIR}/packages"; then
      fx-error "Could not clean up old image."
      exit 2
    fi
  fi
else
  # if the checksum file does not exist, something is inconsistent.
  # so delete the entire directory to make sure we're starting clean.
  # This also happens on a clean run, where the packages directory does not
  # exist.
  if ! rm -rf "${FUCHSIA_IMAGE_WORK_DIR}/packages"; then
    fx-error "Could not clean up old packages."
    exit 2
  fi
fi

if ! mkdir -p "${FUCHSIA_IMAGE_WORK_DIR}/packages"; then
  fx-error "Could not create packages directory."
  exit 2
fi

# if the tarball is not untarred, do it.
if [[ ! -d "${FUCHSIA_IMAGE_WORK_DIR}/packages/amber-files" ]]; then
  if ! tar xzf "${FUCHSIA_IMAGE_WORK_DIR}/${IMAGE_FILENAME}" --directory "${FUCHSIA_IMAGE_WORK_DIR}/packages"; then
    fx-error "Could not extract image from ${FUCHSIA_IMAGE_WORK_DIR}/${IMAGE_FILENAME}."
    exit 1
  fi
  run-md5 "${FUCHSIA_IMAGE_WORK_DIR}/${IMAGE_FILENAME}" > "${CHECKSUM_FILE}"
fi

# Exit out if we only need to prepare the downloads
if [[ "${PREPARE_ONLY}" == "yes" ]]; then
  exit 0
fi

if [[ "${DEVICE_IP_ADDR}" != "" ]]; then
  DEVICE_IP="${DEVICE_IP_ADDR}"
else
  DEVICE_IP=$(get-device-ip-by-name "$DEVICE_NAME_FILTER")
fi

if [[ ! "$?" || -z "$DEVICE_IP" ]]; then
  fx-error "Could not get device IP address"
  exit 2
fi

base_ssh_args=()
if [[ "${SSHCONFIG_FILE}" != "" ]]; then
  base_ssh_args+=("-F" "${SSHCONFIG_FILE}")
fi
if [[ "${PRIVATE_KEY_FILE}" != "" ]]; then
  base_ssh_args+=( "-i" "${PRIVATE_KEY_FILE}")
fi
base_ssh_args+=("${DEVICE_IP}")

# get the host address as seen by the device.
cmd_args=(echo "\$SSH_CONNECTION")
if ! connection_str="$(ssh-cmd "${base_ssh_args[@]}" "${cmd_args[@]}")"; then
  fx-error "unable to determine host address as seen from the target.  Is the target up?"
  exit 1
fi
HOST_IP="$(echo "$connection_str" | cut -d ' ' -f 1)"

if [[ ! "$?" || -z "$HOST_IP" ]]; then
  fx-error "Could not get Host IP address"
  exit 2
fi

# A simple heuristic for "is an ipv6 address", URL encase escape
# the address.
if [[ "${HOST_IP}" =~ : ]]; then
  HOST_IP="${HOST_IP//%/%25}"
  HOST_IP="[${HOST_IP}]"
fi

# kill existing pm if present
kill-running-pm

# Start the package server
echo "** Starting package server in the background**"
# `:port` syntax is valid for Go programs that intend to serve on every
# interface on a given port. For example, if $FUCHSIA_SERVER_PORT is 54321,
# this is similar to serving on [::]:54321 or 0.0.0.0:54321.
"$(get-fuchsia-sdk-tools-dir)/pm" serve -repo "${FUCHSIA_IMAGE_WORK_DIR}/packages/amber-files" -l ":${FUCHSIA_SERVER_PORT}"&


cmd_args=( amber_ctl add_src -f "http://${HOST_IP}:${FUCHSIA_SERVER_PORT}/config.json" -n "${SOURCE_NAME}")

# Update the device to point to the server.
# Because the URL to config.json contains an IPv6 address, the address needs
# to be escaped in square brackets. This is not necessary for the ssh target,
# since that's just an address and not a full URL.
if ! ssh-cmd "${base_ssh_args[@]}" "${cmd_args[@]}" ; then
  fx-error "Error: could not update device"
  exit 1
fi