#!/usr/bin/env bash
################################################################
#   AVD Magisk Setup
################################################################
#
# This script will setup an environment with minimal Magisk that
# Magisk Manager will be happy to run properly within the official
# emulator bundled with Android Studio (AVD).
#
# ONLY use this script for developing Magisk Manager or root apps
# in the emulator. The constructed Magisk environment is not a
# fully functional one as if it is running on an actual device.
#
# The script assumes you are using x86/x64 emulator images.
# Build binaries with `./build.py binary` before running this script.
#
################################################################

abort() {
  echo "$@"
  exit 1
}

mount_sbin() {
  mount -t tmpfs -o 'mode=0755' tmpfs /sbin
  $SELINUX && chcon u:object_r:rootfs:s0 /sbin
}

if [ ! -f /system/build.prop ]; then
  # Running on PC
  cd "`dirname "$0"`/.."
  adb push native/out/x86/busybox scripts/emulator.sh /data/local/tmp
  emu_arch=`adb shell uname -m`
  if [ "$emu_arch" = "x86_64" ]; then
    adb push native/out/x86/magiskinit64 /data/local/tmp/magiskinit
  else
    adb push native/out/x86/magiskinit /data/local/tmp
  fi
  adb root || abort 'adb root failed'
  adb shell sh /data/local/tmp/emulator.sh
  exit 0
fi

cd /data/local/tmp
chmod 777 busybox
chmod 777 magiskinit

# Emulator's adb shell should have root
[ `./busybox id -u` -eq 0 ] || abort 'ADB shell should have root access'

# Check whether already setup
[ -f /sbin/magisk ] && abort "Magisk is already setup"
./busybox pgrep magiskd && abort "Magisk is already setup"

# First setup a good env to work with
rm -rf bin
./busybox mkdir bin
./busybox --install -s bin
OLD_PATH="$PATH"
PATH="/data/local/tmp/bin:$PATH"

# SELinux stuffs
[ -e /sys/fs/selinux ] && SELINUX=true || SELINUX=false
if $SELINUX; then
  ln -sf ./magiskinit magiskpolicy
  ./magiskpolicy --live --magisk 'allow magisk * * *'
fi

# Setup sbin overlay
if mount | grep -q rootfs; then
  mount -o rw,remount /
  rm -rf /root
  mkdir /root
  chmod 750 /root
  ln /sbin/* /root
  mount -o ro,remount /
  mount_sbin
  ln -s /root/* /sbin
else
  mount_sbin
  mkdir -p /sbin/.magisk/mirror/system_root
  block=`mount | grep ' / ' | awk '{ print $1 }'`
  [ $block = "/dev/root" ] && block=/dev/block/dm-0
  mount -o ro $block /sbin/.magisk/mirror/system_root
  for file in /sbin/.magisk/mirror/system_root/sbin/*; do
    [ ! -e $file ] && break
    if [ -L $file ]; then
      cp -af $file /sbin
    else
      sfile=/sbin/`basename $file`
      touch $sfile
      mount -o bind $file $sfile
    fi
  done
fi

# Magisk stuffs
if [ -e /apex ]; then
  ./magiskinit -x magisk /sbin/magisk.bin
  [ -e /system/lib64 ] && LIB=lib64 || LIB=lib
  cat <<EOF > /sbin/magisk
#!/system/bin/sh
export LD_LIBRARY_PATH="\$LD_LIBRARY_PATH:/apex/com.android.runtime/$LIB"
exec /sbin/magisk.bin "\$0" "\$@"
EOF
else
  ./magiskinit -x magisk /sbin/magisk
fi
chmod 755 /sbin/magisk
ln -s ./magisk /sbin/su
ln -s ./magisk /sbin/resetprop
ln -s ./magisk /sbin/magiskhide
mkdir -p /sbin/.magisk/busybox
cp -af ./busybox /sbin/.magisk/busybox/busybox
/sbin/.magisk/busybox/busybox --install -s /sbin/.magisk/busybox
mkdir -p /data/adb/modules 2>/dev/null
mkdir /data/adb/post-fs-data.d 2>/dev/null
mkdir /data/adb/services.d 2>/dev/null
/sbin/magisk --daemon
