#!/bin/bash -e

action="$1"
oldversion="$2"

if [ "$action" != configure ]; then
    exit 0
fi

cmdline=$(</proc/cmdline)
device="unknown"
android_system_dir="unknown"
android_system_img="unknown"
target_checksum="unknown"

#if [[ "$cmdline" =~ ^(.*)androidboot.hardware\=mt6797(.*)$ ]];
#then
#  device="mt6797"
#fi

#if [[ "$cmdline" =~ ^(.*)androidboot.hardware\=mt6771(.*)$ ]];
#then
  device="mt6771"
#fi

#if [[ "$cmdline" =~ ^(.*)androidboot.hardware\=mt6873(.*)$ ]];
#then
#  device="mt6873"
#fi

#if [ -f "/proc/device-tree/model" -a "$device" == unknown ];
#then
#  model=$(</proc/device-tree/model)
#  if [[ "$model" =~ ^(.*)MT6797(.*)$ ]];
#  then
#    device="mt6797"
#  fi

#  if [[ "$model" =~ ^(.*)MT6771(.*)$ ]];
#  then
    device="mt6771"
#  fi

#  if [[ "$model" =~ ^(.*)MT6873(.*)$ ]];
#  then
#    device="mt6873"
#  fi
#fi

if [ "$device" == unknown ]; then
  pid=$$
  while [ "$device" == unknown -a $pid != 1 ]; do
    env=`strings /proc/$pid/environ`
    device=`echo "$env"|awk -F= '$1 == "TARGET_DEVICE" { print $2; }'`
    pid=`ps -oppid -p$pid|tail -1|awk '{print $1}'`
  done
fi

#case $device in
#"mt6797")
#  android_system_dir="/data"
#  android_system_img="/data/system.img"
#  target_checksum="39cd17718e838823c80be0ddfc9763d88e32c1b0"
#  ;;
#"mt6771")
  android_system_dir="/var/lib/lxc/android"
  android_system_img="/var/lib/lxc/android/android-rootfs.img"
  target_checksum="f8b91bd83795c62f1e9b33be9a4156bdf4a90658"
#  ;;
#"mt6873")
#  android_system_dir="/var/lib/lxc/android"
#  android_system_img="/var/lib/lxc/android/android-rootfs.img"
#  target_checksum="ac89776ea0c06fe7148237cdf800cb917cdd985d"
#  ;;
#esac

if cmp -s /lib/udev/rules.d/80-keyboard.rules /usr/lib/gemian/udev-rules/80-keyboard-$device.rules;
then
  echo Keyboard rules in place
else
  cp /usr/lib/gemian/udev-rules/80-keyboard-$device.rules /lib/udev/rules.d/80-keyboard.rules
fi

if cmp -s /lib/udev/rules.d/70-$device.rules /usr/lib/gemian/udev-rules/70-$device.rules;
then
  echo Device rules in place
else
  cp /usr/lib/gemian/udev-rules/70-$device.rules /lib/udev/rules.d/
fi

echo "Target checksum $target_checksum"

echo "Checking $android_system_img"

current_checksum="$(sha1sum $android_system_img | cut -d' ' -f1)"

echo "Checksum $current_checksum"

if [ "$target_checksum" == "$current_checksum" ];
then
  echo "Android system image upto date"
  exit 0
else
  tempfile="$(mktemp)"
  rm $tempfile
  echo "Downloading new Android system image"
  curl -k https://gemian.thinkglobally.org/system/system.$target_checksum.img.xz --output $tempfile.xz
  xz -d $tempfile.xz
  downloaded_checksum="$(sha1sum $tempfile | cut -d' ' -f1)"
  if [ "$target_checksum" == "$downloaded_checksum" ];
  then
    echo "Moving new system image into place, please reboot to activate"
    mkdir -p $android_system_dir
    mv $tempfile $android_system_img
    exit 0
  else
    echo "Downloaded checksum fail - check your internet for random errors or man in the middle attacks and retry"
    exit 1
  fi
fi