#!/bin/bash

if [[ $EUID -ne 0 ]]; then
   echo "This script must be run as root (use sudo)" 1>&2
   exit 1
fi


ver="0.1"

# we create a dir with this version to ensure that 'dkms remove' won't delete
# the sources during kernel updates
marker="0.0.0"

apt update
apt-get -y install raspberrypi-kernel-headers raspberrypi-kernel
apt-get -y install  dkms

# locate currently installed kernels (may be different to running kernel if
# it's just been updated)
kernel="$(uname -r)"

function install_module {
  src=$1
  mod=$2

  if [[ -d /var/lib/dkms/$mod/$ver/$marker ]]; then
    rmdir /var/lib/dkms/$mod/$ver/$marker
  fi

  if [[ -e /usr/src/$mod-$ver || -e /var/lib/dkms/$mod/$ver ]]; then
    dkms remove -m $mod -v $ver --all
    rm -rf /usr/src/$mod-$ver
  fi
  mkdir -p /usr/src/$mod-$ver
  cp -a $src/* /usr/src/$mod-$ver/
  dkms add -m $mod -v $ver
  dkms build -k $kernel -m $mod -v $ver && dkms install -k $kernel -m $mod -v $ver

  mkdir -p /var/lib/dkms/$mod/$ver/$marker
}

install_module "./" "seeed-voicecard"


(
  cp seeed-voicecard.dtbo /boot/overlays
  cp asound.state /var/lib/alsa/asound.state
)

echo 'wm8960' | sudo tee --append /etc/modules > /dev/null

sed -i \
  -e "s/^dtparam=audio=on/#\0/" \
  -e "s/^#\(dtparam=i2s=on\)/\1/" \
  /boot/config.txt
grep -q "dtoverlay=i2s-mmap" /boot/config.txt || \
  echo "dtoverlay=i2s-mmap" >> /boot/config.txt
grep -q "dtoverlay=seeed-voicecard" /boot/config.txt || \
  echo "dtoverlay=seeed-voicecard" >> /boot/config.txt
grep -q "dtparam=i2s=on" /boot/config.txt || \
  echo "dtparam=i2s=on" >> /boot/config.txt

echo "------------------------------------------------------"
echo "Please reboot your raspberry pi to apply all settings"
echo "Enjoy!"
echo "------------------------------------------------------"