#!/bin/bash
################################################################################
#      This file is part of LibreELEC - http://www.libreelec.tv
#      Copyright (C) 2009-2016 Team LibreELEC
#
#  LibreELEC is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation, either version 2 of the License, or
#  (at your option) any later version.
#
#  LibreELEC is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with LibreELEC.  If not, see <http://www.gnu.org/licenses/>.
################################################################################
set -e

LIBREELEC_DIR=$HOME/LibreELEC.tv
TARGET_DIR=/var/www/sources
DOWNLOAD_DIR=$HOME/download
REVISION=
PACKAGE=
DRYRUN=no
IGNORE_ERRORS=no
DOGIT=no
PROGRESS=yes
ISMIRROR=yes
VERBOSE=no

[ -z "${PROJECT}" ] && PROJECT=Generic
[ -z "${ARCH}" ]    && ARCH=x86_64

if command -v tput >/dev/null; then
  TXRED="$(tput setaf 1 bold)"
  TXGREEN="$(tput setaf 2 bold)"
  TXYELLOW="$(tput setaf 3 bold)"
  TXBLUE="$(tput setaf 4 bold)"
  TXMAGENTA="$(tput setaf 5 bold)"
  TXCYAN="$(tput setaf 6 bold)"
  TXRESET="$(tput sgr0)"
fi

help() {
  [ -n "$1" ] && echo -e "ERROR: Unknown argument [$1]\n"
  cat <<EOF
Usage: $(basename $0) -d|--download <path> [-t|--target <path>] [-l|--libreelec <path>]
           [-m|--mirror] [-s|--source] [-a|-all] [-p|--package <package_name> [-r|--revision <revision>]]
          [--git] [--dry-run] [--noprogress] [-v|--verbose] [-h|--help]

Options:
  -d, --download:   Directory path into which new package files will be downloaded - default is $HOME/download[1]
  -t, --target:     Directory path for existing packages that are to be refreshed, default is /var/www/sources[2]
  -l, --libreelec:  LibreELEC.tv repo, default is ${HOME}/LibreELEC.tv
  -m, --mirror:     Target is mirror not source - mirror uses a hierarchical per-package folder structure
  -s, --source:     Target is source not mirror - source uses a flattened file structure. Default is mirror
  -a, --all:        Ignore download failures, continue processing all packages
  -p, --package:    Package to process, otherwise process all packages
  -r, --revision:   Version to use in place of PKG_VERSION, only applicable in conjunction with -p
      --git:        Clone (if not available) or pull the LibreELEC.tv repository
      --dry-run:    Don't actually download anything (will still git clone/pull if configured)
      --noprogress: Do not show progress indicator
  -v, --verbose:    Output more verbose sync information
  -h, --help:      This message

  Note#1. The download directory will have the LibreELEC version appended (eg. /devel) unless it is a mirror, in which case "/mirror" will be appended.
  Note#2. The target directory will have the LibreELEC version appended (eg. /devel) unless it is a mirror, in which case "/mirror" will be appended.
EOF
}

get_libreelec_branch() {
  cd $LIBREELEC_DIR
  git rev-parse --abbrev-ref HEAD
}

# 1: LibreELEC variable, eg. LIBREELEC_VERSION
get_libreelec_option() {
  local variable="$1"
  cd $LIBREELEC_DIR
  . config/options
  echo "${!variable}"
}

# 1: name of package
# 2: package variable, eg. PKG_URL
get_pkg_option() {
  local package="$1" variable="$2"
  cd $LIBREELEC_DIR
  . config/options ${package} 2>/dev/null
  echo "${!variable}"
}

# Return success if the specified package is not found locally
need_package() {
  local package_name="$1"
  local package_source="$2"

  if [ ${ISMIRROR} == no ]; then
    [ -f ${TARGET_DIR}/${package_source} ] && return 1
    [ -f ${DOWNLOAD_DIR}/${package_source} ] && return 1
  else
    [ -f ${TARGET_DIR}/${package_name}/${package_source} ] && return 1
    [ -f ${DOWNLOAD_DIR}/${package_name}/${package_source} ] && return 1
  fi

  return 0
}

remote_file_exists() {
  [ "$(curl -sfIL --connect-timeout 15 --retry 3  -w "%{http_code}" -o /dev/null ${1} 2>/dev/null)" == "404" ] && return 1 || return 0
}

download_file() {
  local url="$1"
  local retries=10
  local attempts=0

  while [ ${attempts} -lt ${retries} ]; do
    attempts=$((attempts + 1))
    wget --timeout=30 --tries=3 --passive-ftp --no-check-certificate -O ${DOWNLOAD_DIR}/.tmp ${url} 2>/tmp/sync.log && return 0
  done
  return 1
}

# Download the specified package
getkpkg() {
  local package_name="$1"
  local package_source="$2"
  local package_url="$3"
  local result
  local onsource=no onmirror=no

  [ -n "${package_url}" ] || return 0

  remote_file_exists ${package_url} && onsource=yes
  if [ ${onsource} == no ]; then
    remote_file_exists ${DISTRO_MIRROR}/${package_name}/${package_source} && onmirror=yes
  fi

  # If the PKG_URL is the DISTRO_SRC server...
  if [[ ${package_url} =~ ^${DISTRO_SOURCE}.* ]]; then
    # Warn the user if package is not found on either source or mirror
    if [ ${onsource} == no -a ${onmirror} == no ]; then
      echo "${LINE_PREFIX}${TXMAGENTA}PACKAGE UPDATE OR MKPKG REQUIRED?${TXRESET}: Unable to download ${package_name} from url ${package_url} (and not on mirror)" >&2
      return 0
    fi
  fi

  if [ ${DRYRUN} == yes ]; then
    echo -n "${LINE_PREFIX}Downloading package: ${package_name} (${package_source})..."
    [ ${onsource} == yes -o ${onmirror} == yes ] && echo -n " ${TXGREEN}AVAILABLE${TXRESET}" || echo -n " ${TXRED}NOT AVAILABLE${TXRESET} ${package_url}"
    [ ${onsource} == no  -a ${onmirror} == yes ] && echo " ${TXYELLOW}(found on mirror)${TXRESET}" || echo
    return 0
  fi

  rm -f ${DOWNLOAD_DIR}/.tmp /tmp/sync.log

  echo -n "${LINE_PREFIX}Downloading package: ${package_name} (${package_source})..."

  if [ ${onsource} == yes ]; then
    download_file ${package_url} && result=0 || result=1
  elif [ ${onmirror} == yes ]; then
    download_file ${DISTRO_MIRROR}/${package_name}/${package_source} && result=0 || result=1
  else
    result=1
  fi

  if [ ${result} -ne 0 -o ! -s ${DOWNLOAD_DIR}/.tmp ]; then
    echo " ${TXRED}FAILED!!${TXRESET}"
    [ -f /tmp/sync.log ] && cat /tmp/sync.log >&2
    rm -f ${DOWNLOAD_DIR}/.tmp
  else
    echo " ${TXGREEN}OK${TXRESET}"
    if [ ${ISMIRROR} == yes ]; then
      mkdir -p ${DOWNLOAD_DIR}/${package_name}
      mv ${DOWNLOAD_DIR}/.tmp ${DOWNLOAD_DIR}/${package_name}/${package_source}
    else
      mv ${DOWNLOAD_DIR}/.tmp ${DOWNLOAD_DIR}/${package_source}
    fi
  fi

  [ ${IGNORE_ERRORS} == yes ] && return 0 || return ${result}
}

check_single_package() {
  local package_name="$1" revision="$2"
  local package_dir="$(cd ${LIBREELEC_DIR}; find packages -type d -name ${PACKAGE})"

  if [ -n "${package_dir}" ]; then
    if [ -f ${LIBREELEC_DIR}/${package_dir}/package.mk ]; then
      check_package "${package_dir}/package.mk" "${revision}"
      return 0
    else
      echo "ERROR: ${package_name} is not a valid package - package.mk does not exist"
    fi
  else
    echo "ERROR: ${package_name} is not a valid package - directory does not exist"
  fi
  return 1
}

# Download a package if required
check_package() {
  local package_file="$1" revision="$2"
  local package_name="$(basename $(dirname ${package_file}))"
  local package_source package_url package_ver

  package_source="$(get_pkg_option "${package_name}" PKG_SOURCE_NAME)"
  if [ -n "${revision}" ]; then
    package_ver=$(get_pkg_option "${package_name}" PKG_VERSION)
    package_source="${package_source/${package_ver}/${revision}}"
  fi

  [ -n "${package_source}" ] || return 0

  if need_package "${package_name}" "${package_source}"; then
    package_url="$(get_pkg_option "${package_name}" PKG_URL)"
    if [ -n "${revision}" ]; then
      package_url="${package_url/${package_ver}/${revision}}"
    fi
    getkpkg  "${package_name}" "${package_source}" "${package_url}"
  else
    [ ${VERBOSE} == yes ] && echo "${LINE_PREFIX}Already downloaded : ${package_name} (${package_source}) ${TXGREEN}OK${TXRESET}" || true
  fi
}

check_exists() {
  if [ -z "${!1}" ]; then
    echo "ERROR: ${1} must not be undefined"
    return 1
  fi

  [ -d ${!1} ] && return 0

  echo "ERROR: ${1} ${!1} does not exist"
  return 1
}

get_abs_path() {
  echo "$(readlink -f $1)"
}

get_package_path() {
  echo "$(basename "$(dirname "$0")") $0"
}

get_packages() {
  export -f get_package_path
  cd $LIBREELEC_DIR
  find packages -name package.mk -exec bash -c get_package_path "{}" \; | sort -k1 | cut -d' ' -f2-
}

COUNT=0
progress() {
  COUNT=$((COUNT + 1))
  printf "Working... %3d%%\r" $((COUNT * 100 / $1))
}

while [ : ]; do
  [ -z "$1" ] && break
  case $1 in
    -d|--download)
      shift
      DOWNLOAD_DIR=$1
      ;;
    -l|--libreelec)
      shift
      LIBREELEC_DIR=$1
      ;;
    -t|--target)
      shift
      TARGET_DIR=$1
      ;;
    -a|--all)
      IGNORE_ERRORS=yes
      ;;
    -p|--package)
      shift
      PACKAGE=$1
      VERBOSE=yes
      ;;
    -r|--revision)
      shift
      REVISION=$1
      ;;
    -m|--mirror)
      ISMIRROR=yes
      ;;
    -s|--source)
      ISMIRROR=no
      ;;
    --dry-run|--dryrun)
      DRYRUN=yes
      LINE_PREFIX="**DRY-RUN** "
      ;;
    --git)
      DOGIT=yes
      ;;
    -v|--verbose)
      VERBOSE=yes
      ;;
    --noprogress)
      PROGRESS=no
      ;;
    -h|--help)
      help
      exit 0
      ;;
    *)
      help "$1"
      exit 0
      ;;
  esac
  shift
done

if [ ${DOGIT} == yes ]; then
  (
    if [ -d ${LIBREELEC_DIR}/.git ]; then
      cd ${LIBREELEC_DIR}
      git pull
    else
      mkdir -p $(dirname "${LIBREELEC_DIR}") 2>/dev/null
      cd $(dirname "${LIBREELEC_DIR}")
      git clone https://github.com/LibreELEC/LibreELEC.tv.git $(basename "${LIBREELEC_DIR}")
    fi
  )
fi

check_exists LIBREELEC_DIR || exit
LIBREELEC_DIR="$(get_abs_path "${LIBREELEC_DIR}")"

DISTRO_SOURCE="$(get_libreelec_option DISTRO_SRC)"
DISTRO_MIRROR="$(get_libreelec_option DISTRO_MIRROR)"
LIBREELEC_VER="$(get_libreelec_option LIBREELEC_VERSION)"

if [ ${ISMIRROR} == no ]; then
  TARGET_DIR="$(get_abs_path "${TARGET_DIR}/${LIBREELEC_VER}")"
else
  TARGET_DIR="$(get_abs_path "${TARGET_DIR}/mirror")"
fi
check_exists TARGET_DIR || exit

if [ ${ISMIRROR} == no ]; then
  DOWNLOAD_DIR="$(get_abs_path "${DOWNLOAD_DIR}/${LIBREELEC_VER}")"
else
  DOWNLOAD_DIR="$(get_abs_path "${DOWNLOAD_DIR}/mirror")"
fi
check_exists DOWNLOAD_DIR || exit

if [ -n "${REVISION}" -a -z "${PACKAGE}" ]; then
  echo "ERROR: A single package must be specified with custom revision"
  exit 1
fi

echo
if [ ${ISMIRROR} == yes ]; then
  echo "Synchronising LibreELEC.tv (branch: $(get_libreelec_branch), version: ${LIBREELEC_VER}) with MIRROR server ${TARGET_DIR}"
else
  echo "Synchronising LibreELEC.tv (branch: $(get_libreelec_branch), version: ${LIBREELEC_VER}) with SOURCE server ${TARGET_DIR}"
fi
echo
echo "Distro Source is: ${DISTRO_SOURCE}"
echo "Distro Mirror is: ${DISTRO_MIRROR}"
echo " Syncing against: ${TARGET_DIR}"
echo "  Downloading to: ${DOWNLOAD_DIR}"
echo "         Dry run: ${DRYRUN^}"
echo

[ -z "${NODELAY}" ] && echo -n "Sync starts in 5 seconds..." && sleep 5 && echo -en "\n\n"

if [ -n "${PACKAGE}" ]; then
  check_single_package "${PACKAGE}" "${REVISION}"
else
  packages="$(get_packages)"
  pcount="$(echo "${packages}" | wc -l)"
  for package_mk in ${packages}; do
    [ ${PROGRESS} == yes ] && progress ${pcount}
    check_package ${package_mk}
  done
fi