#!/sbin/sh
##########################################################################################
#
# Magisk Uninstaller
# by topjohnwu
# 
# This zip will remove all Magisk related files and revert boot image
#
##########################################################################################

INSTALLER=/tmp/uninstall

# Default permissions
umask 022

##########################################################################################
# Flashable update-binary preparation
##########################################################################################

OUTFD=$2
ZIP=$3

readlink /proc/$$/fd/$OUTFD 2>/dev/null | grep /tmp >/dev/null
if [ "$?" -eq "0" ]; then
  OUTFD=0

  for FD in `ls /proc/$$/fd`; do
    readlink /proc/$$/fd/$FD 2>/dev/null | grep pipe >/dev/null
    if [ "$?" -eq "0" ]; then
      ps | grep " 3 $FD " | grep -v grep >/dev/null
      if [ "$?" -eq "0" ]; then
        OUTFD=$FD
        break
      fi
    fi
  done
fi

mkdir -p $INSTALLER
cd $INSTALLER
unzip -o "$ZIP"

##########################################################################################
# Functions
##########################################################################################

ui_print() {
  echo -n -e "ui_print $1\n" >> /proc/self/fd/$OUTFD
  echo -n -e "ui_print\n" >> /proc/self/fd/$OUTFD
}

getvar() {
  local VARNAME=$1
  local VALUE=$(eval echo \$"$VARNAME");
  for FILE in /data/.magisk /cache/.magisk /system/.magisk; do
    if [ -z "$VALUE" ]; then
      LINE=$(cat $FILE 2>/dev/null | grep "$VARNAME=")
      if [ ! -z "$LINE" ]; then
        VALUE=${LINE#*=}
      fi
    fi
  done
  eval $VARNAME=\$VALUE
}

is_mounted() {
  if [ ! -z "$2" ]; then
    cat /proc/mounts | grep $1 | grep $2, >/dev/null
  else
    cat /proc/mounts | grep $1 >/dev/null
  fi
  return $?
}

grep_prop() {
  REGEX="s/^$1=//p"
  shift
  FILES=$@
  if [ -z "$FILES" ]; then
    FILES='/system/build.prop'
  fi
  cat $FILES 2>/dev/null | sed -n $REGEX | head -n 1
}

##########################################################################################
# Main
##########################################################################################

ui_print "*****************************"
ui_print "      Magisk Uninstaller     "
ui_print "*****************************"

if [ ! -d "$INSTALLER/arm" ]; then
  ui_print "! Failed: Unable to extract zip file!"
  exit 1
fi

ui_print "- Mounting /system(ro), /cache, /data"
mount -o ro /system 2>/dev/null
mount /cache 2>/dev/null
mount /data 2>/dev/null

if [ ! -f '/system/build.prop' ]; then
  ui_print "! Failed: /system could not be mounted!"
  exit 1
fi

API=$(grep_prop ro.build.version.sdk)
ABI=$(grep_prop ro.product.cpu.abi | cut -c-3)
ABI2=$(grep_prop ro.product.cpu.abi2 | cut -c-3)
ABILONG=$(grep_prop ro.product.cpu.abi)

ARCH=arm
IS64BIT=false
if [ "$ABI" = "x86" ]; then ARCH=x86; fi;
if [ "$ABI2" = "x86" ]; then ARCH=x86; fi;
if [ "$ABILONG" = "arm64-v8a" ]; then ARCH=arm64; IS64BIT=true; fi;
if [ "$ABILONG" = "x86_64" ]; then ARCH=x64; IS64BIT=true; fi;

ui_print "- Device platform: $ARCH"
CHROMEDIR=$INSTALLER/chromeos
BINDIR=$INSTALLER/$ARCH

# Copy the binaries to /data/magisk
mkdir -p /data/magisk 2>/dev/null
cp -af $BINDIR/* $CHROMEDIR /data/magisk

##########################################################################################
# Detection all done, start installing
##########################################################################################

ui_print "- Found Boot Image: $BOOTIMAGE"

if (is_mounted /data); then
  ui_print "- Running uninstaller scripts"
  sh $INSTALLER/common/magisk_uninstaller.sh
  if [ $? -ne 0 ]; then
    ui_print "! Magisk is not installed or an error occurred"
    exit 1
  fi
else
  ui_print "! Data unavailable"
  ui_print "! Placing uninstall script to /cache"
  ui_print "! The device might reboot multiple times"
  cp -af $INSTALLER/common/magisk_uninstaller.sh /cache/magisk_uninstaller.sh
  umount /system
  ui_print "- Rebooting....."
  sleep 5
  reboot
fi

umount /system
ui_print "- Done"
exit 0