#!/bin/sh
################################################################################
#      This file is part of LibreELEC - https://libreelec.tv
#      Copyright (C) 2017-present 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/>.
################################################################################

SYSTEM_OVERLAYS_DIR=/usr/lib/kernel-overlays
OVERLAY_CONFIG_DIR=/storage/.cache/kernel-overlays
KVER=$(uname -r)
MODULES_DIR="/var/lib/modules/${KVER}"
FIRMWARE_DIR="/var/lib/firmware"

mkdir -p "${MODULES_DIR}"
mkdir -p "${FIRMWARE_DIR}"
mkdir -p "${OVERLAY_CONFIG_DIR}"

log() {
  echo "kernel-overlays-setup: $@" > /dev/kmsg
}

apply_overlay() {
  case "$1" in
    /*)
      modules_overlay_dir="${1}/lib/modules/${KVER}"
      firmware_overlay_dir="${1}/lib/firmware"
      ;;
    *)
      modules_overlay_dir="${SYSTEM_OVERLAYS_DIR}/${1}/lib/modules/${KVER}"
      firmware_overlay_dir="${SYSTEM_OVERLAYS_DIR}/${1}/lib/firmware"
      ;;
  esac

  if [ -d "${modules_overlay_dir}" ] ; then
    GOT_MODULE_OVERLAY="yes"

    if cp -rfs "${modules_overlay_dir}"/* "${MODULES_DIR}" ; then
      log "added modules from $modules_overlay_dir"
    else
      log "failed to add modules from $modules_overlay_dir"
    fi
  fi

  if [ -d "${firmware_overlay_dir}" ] ; then
    if cp -rfs "${firmware_overlay_dir}"/* "${FIRMWARE_DIR}" ; then
      log "added firmware from $firmware_overlay_dir"
    else
      log "failed to add firmware from $firmware_overlay_dir"
    fi
  fi
}

# setup system base modules

log "setup base modules"
apply_overlay base

# apply user-configured module overlays

if [ -d "${OVERLAY_CONFIG_DIR}" ] ; then
  log "adding overlays from ${OVERLAY_CONFIG_DIR}"
  GOT_MODULE_OVERLAY="no"

  for conf in "${OVERLAY_CONFIG_DIR}/"*.conf ; do
    if [ -e "$conf" ] ; then
      log "processing conf $conf"
      overlay=$(cat "$conf")
      [ -n "$overlay" ] && apply_overlay "$overlay"
    fi
  done

  if [ "yes" = "$GOT_MODULE_OVERLAY" ] ; then
    log "running depmod"
    /usr/sbin/depmod -a
  fi
fi

log "done"