#########################################
#
# Magisk General Utility Functions
# by topjohnwu
#
#########################################

##########
# Presets
##########

MAGISK_VER="20.2-b29f0ca4"
MAGISK_VER_CODE=20105

# Detect whether in boot mode
[ -z $BOOTMODE ] && BOOTMODE=false
$BOOTMODE || ps | grep zygote | grep -qv grep && BOOTMODE=true
$BOOTMODE || ps -A 2>/dev/null | grep zygote | grep -qv grep && BOOTMODE=true

# Presets
MAGISKTMP=/sbin/.magisk
NVBASE=/data/adb
[ -z $TMPDIR ] && TMPDIR=/dev/tmp

# Bootsigner related stuff
BOOTSIGNERCLASS=a.a
BOOTSIGNER="/system/bin/dalvikvm -Xnodex2oat -Xnoimage-dex2oat -cp \$APK \$BOOTSIGNERCLASS"
BOOTSIGNED=false

###################
# Helper Functions
###################

ui_print() {
  $BOOTMODE && echo "$1" || echo -e "ui_print $1\nui_print" >> /proc/self/fd/$OUTFD
}

toupper() {
  echo "$@" | tr '[:lower:]' '[:upper:]'
}

grep_cmdline() {
  local REGEX="s/^$1=//p"
  cat /proc/cmdline | tr '[:space:]' '\n' | sed -n "$REGEX" 2>/dev/null
}

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

getvar() {
  local VARNAME=$1
  local VALUE=
  VALUE=`grep_prop $VARNAME /sbin/.magisk/config /data/.magisk /cache/.magisk`
  [ ! -z $VALUE ] && eval $VARNAME=\$VALUE
}

is_mounted() {
  grep -q " `readlink -f $1` " /proc/mounts 2>/dev/null
  return $?
}

abort() {
  ui_print "$1"
  $BOOTMODE || recovery_cleanup
  exit 1
}

resolve_vars() {
  MAGISKBIN=$NVBASE/magisk
  POSTFSDATAD=$NVBASE/post-fs-data.d
  SERVICED=$NVBASE/service.d
}

######################
# Environment Related
######################

setup_flashable() {
  # Preserve environment varibles
  OLD_PATH=$PATH
  ensure_bb
  $BOOTMODE && return
  if [ -z $OUTFD ] || readlink /proc/$$/fd/$OUTFD | grep -q /tmp; then
    # We will have to manually find out OUTFD
    for FD in `ls /proc/$$/fd`; do
      if readlink /proc/$$/fd/$FD | grep -q pipe; then
        if ps | grep -v grep | grep -q " 3 $FD "; then
          OUTFD=$FD
          break
        fi
      fi
    done
  fi
}

ensure_bb() {
  if [ -x $MAGISKTMP/busybox/busybox ]; then
    [ -z $BBDIR ] && BBDIR=$MAGISKTMP/busybox
  elif [ -x $TMPDIR/bin/busybox ]; then
    [ -z $BBDIR ] && BBDIR=$TMPDIR/bin
  else
    # Construct the PATH
    [ -z $BBDIR ] && BBDIR=$TMPDIR/bin
    mkdir -p $BBDIR
    ln -s $MAGISKBIN/busybox $BBDIR/busybox
    $MAGISKBIN/busybox --install -s $BBDIR
  fi
  echo $PATH | grep -q "^$BBDIR" || export PATH=$BBDIR:$PATH
}

recovery_actions() {
  # Make sure random don't get blocked
  mount -o bind /dev/urandom /dev/random
  # Unset library paths
  OLD_LD_LIB=$LD_LIBRARY_PATH
  OLD_LD_PRE=$LD_PRELOAD
  OLD_LD_CFG=$LD_CONFIG_FILE
  unset LD_LIBRARY_PATH
  unset LD_PRELOAD
  unset LD_CONFIG_FILE
  # Force our own busybox path to be in the front
  # and do not use anything in recovery's sbin
  export PATH=$BBDIR:/system/bin:/vendor/bin
}

recovery_cleanup() {
  export PATH=$OLD_PATH
  [ -z $OLD_LD_LIB ] || export LD_LIBRARY_PATH=$OLD_LD_LIB
  [ -z $OLD_LD_PRE ] || export LD_PRELOAD=$OLD_LD_PRE
  [ -z $OLD_LD_CFG ] || export LD_CONFIG_FILE=$OLD_LD_CFG
  ui_print "- Unmounting partitions"
  umount -l /system_root 2>/dev/null
  umount -l /system 2>/dev/null
  umount -l /vendor 2>/dev/null
  umount -l /dev/random 2>/dev/null
}

#######################
# Installation Related
#######################

find_block() {
  for BLOCK in "$@"; do
    DEVICE=`find /dev/block -type l -iname $BLOCK | head -n 1` 2>/dev/null
    if [ ! -z $DEVICE ]; then
      readlink -f $DEVICE
      return 0
    fi
  done
  # Fallback by parsing sysfs uevents
  for uevent in /sys/dev/block/*/uevent; do
    local DEVNAME=`grep_prop DEVNAME $uevent`
    local PARTNAME=`grep_prop PARTNAME $uevent`
    for BLOCK in "$@"; do
      if [ "`toupper $BLOCK`" = "`toupper $PARTNAME`" ]; then
        echo /dev/block/$DEVNAME
        return 0
      fi
    done
  done
  return 1
}

mount_part() {
  $BOOTMODE && return
  local PART=$1
  local POINT=/${PART}
  [ -L $POINT ] && rm -f $POINT
  mkdir $POINT 2>/dev/null
  is_mounted $POINT && return
  ui_print "- Mounting $PART"
  mount -o ro $POINT 2>/dev/null
  if ! is_mounted $POINT; then
    local BLOCK=`find_block $PART$SLOT`
    mount -o ro $BLOCK $POINT
  fi
  is_mounted $POINT || abort "! Cannot mount $POINT"
}

mount_partitions() {
  # Check A/B slot
  SLOT=`grep_cmdline androidboot.slot_suffix`
  if [ -z $SLOT ]; then
    SLOT=`grep_cmdline androidboot.slot`
    [ -z $SLOT ] || SLOT=_${SLOT}
  fi
  [ -z $SLOT ] || ui_print "- Current boot slot: $SLOT"

  mount_part system
  if [ -f /system/init.rc ]; then
    SYSTEM_ROOT=true
    [ -L /system_root ] && rm -f /system_root
    mkdir /system_root 2>/dev/null
    mount --move /system /system_root
    mount -o bind /system_root/system /system
  else
    grep ' / ' /proc/mounts | grep -qv 'rootfs' || grep -q ' /system_root ' /proc/mounts \
    && SYSTEM_ROOT=true || SYSTEM_ROOT=false
  fi
  [ -L /system/vendor ] && mount_part vendor
  $SYSTEM_ROOT && ui_print "- Device is system-as-root"
}

get_flags() {
  # override variables
  getvar KEEPVERITY
  getvar KEEPFORCEENCRYPT
  getvar RECOVERYMODE
  if [ -z $KEEPVERITY ]; then
    if $SYSTEM_ROOT; then
      KEEPVERITY=true
      ui_print "- System-as-root, keep dm/avb-verity"
    else
      KEEPVERITY=false
    fi
  fi
  if [ -z $KEEPFORCEENCRYPT ]; then
    grep ' /data ' /proc/mounts | grep -q 'dm-' && FDE=true || FDE=false
    [ -d /data/unencrypted ] && FBE=true || FBE=false
    # No data access means unable to decrypt in recovery
    if $FDE || $FBE || ! $DATA; then
      KEEPFORCEENCRYPT=true
      ui_print "- Encrypted data, keep forceencrypt"
    else
      KEEPFORCEENCRYPT=false
    fi
  fi
  [ -z $RECOVERYMODE ] && RECOVERYMODE=false
}

find_boot_image() {
  BOOTIMAGE=
  if $RECOVERYMODE; then
    BOOTIMAGE=`find_block recovery_ramdisk$SLOT recovery`
  elif [ ! -z $SLOT ]; then
    BOOTIMAGE=`find_block ramdisk$SLOT recovery_ramdisk$SLOT boot$SLOT`
  else
    BOOTIMAGE=`find_block ramdisk recovery_ramdisk kern-a android_boot kernel boot lnx bootimg boot_a`
  fi
  if [ -z $BOOTIMAGE ]; then
    # Lets see what fstabs tells me
    BOOTIMAGE=`grep -v '#' /etc/*fstab* | grep -E '/boot[^a-zA-Z]' | grep -oE '/dev/[a-zA-Z0-9_./-]*' | head -n 1`
  fi
}

flash_image() {
  # Make sure all blocks are writable
  $MAGISKBIN/magisk --unlock-blocks 2>/dev/null
  case "$1" in
    *.gz) CMD1="$MAGISKBIN/magiskboot decompress '$1' - 2>/dev/null";;
    *)    CMD1="cat '$1'";;
  esac
  if $BOOTSIGNED; then
    CMD2="$BOOTSIGNER -sign"
    ui_print "- Sign image with verity keys"
  else
    CMD2="cat -"
  fi
  if [ -b "$2" ]; then
    local img_sz=`stat -c '%s' "$1"`
    local blk_sz=`blockdev --getsize64 "$2"`
    [ $img_sz -gt $blk_sz ] && return 1
    eval $CMD1 | eval $CMD2 | cat - /dev/zero > "$2" 2>/dev/null
  else
    ui_print "- Not block device, storing image"
    eval $CMD1 | eval $CMD2 > "$2" 2>/dev/null
  fi
  return 0
}

find_dtbo_image() {
  DTBOIMAGE=`find_block dtbo$SLOT`
}

patch_dtbo_image() {
  find_dtbo_image
  if [ ! -z $DTBOIMAGE ]; then
    ui_print "- DTBO image: $DTBOIMAGE"
    local PATCHED=$TMPDIR/dtbo
    if $MAGISKBIN/magiskboot dtb $DTBOIMAGE patch $PATCHED; then
      ui_print "- Backing up stock DTBO image"
      $MAGISKBIN/magiskboot compress $DTBOIMAGE $MAGISKBIN/stock_dtbo.img.gz
      ui_print "- Patching DTBO to remove avb-verity"
      cat $PATCHED /dev/zero > $DTBOIMAGE
      rm -f $PATCHED
      return 0
    fi
  fi
  return 1
}

patch_boot_image() {
  # Common installation script for flash_script.sh (updater-script) and addon.d.sh
  SOURCEDMODE=true
  cd $MAGISKBIN

  eval $BOOTSIGNER -verify < $BOOTIMAGE && BOOTSIGNED=true
  $BOOTSIGNED && ui_print "- Boot image is signed with AVB 1.0"

  $IS64BIT && mv -f magiskinit64 magiskinit 2>/dev/null || rm -f magiskinit64

  # Source the boot patcher
  . ./boot_patch.sh "$BOOTIMAGE"

  ui_print "- Flashing new boot image"

  if ! flash_image new-boot.img "$BOOTIMAGE"; then
    ui_print "- Compressing ramdisk to fit in partition"
    ./magiskboot cpio ramdisk.cpio compress
    ./magiskboot repack "$BOOTIMAGE"
    flash_image new-boot.img "$BOOTIMAGE" || abort "! Insufficient partition size"
  fi

  ./magiskboot cleanup
  rm -f new-boot.img

  if [ -f stock_boot* ]; then
    rm -f /data/stock_boot* 2>/dev/null
    $DATA && mv stock_boot* /data
  fi

  # Patch DTBO together with boot image
  $KEEPVERITY || patch_dtbo_image

  if [ -f stock_dtbo* ]; then
    rm -f /data/stock_dtbo* 2>/dev/null
    $DATA && mv stock_dtbo* /data
  fi
}

sign_chromeos() {
  ui_print "- Signing ChromeOS boot image"

  echo > empty
  ./chromeos/futility vbutil_kernel --pack new-boot.img.signed \
  --keyblock ./chromeos/kernel.keyblock --signprivate ./chromeos/kernel_data_key.vbprivk \
  --version 1 --vmlinuz new-boot.img --config empty --arch arm --bootloader empty --flags 0x1

  rm -f empty new-boot.img
  mv new-boot.img.signed new-boot.img
}

remove_system_su() {
  if [ -f /system/bin/su -o -f /system/xbin/su ] && [ ! -f /su/bin/su ]; then
    ui_print "- Removing system installed root"
    mount -o rw,remount /system
    # SuperSU
    if [ -e /system/bin/.ext/.su ]; then
      mv -f /system/bin/app_process32_original /system/bin/app_process32 2>/dev/null
      mv -f /system/bin/app_process64_original /system/bin/app_process64 2>/dev/null
      mv -f /system/bin/install-recovery_original.sh /system/bin/install-recovery.sh 2>/dev/null
      cd /system/bin
      if [ -e app_process64 ]; then
        ln -sf app_process64 app_process
      elif [ -e app_process32 ]; then
        ln -sf app_process32 app_process
      fi
    fi
    rm -rf /system/.pin /system/bin/.ext /system/etc/.installed_su_daemon /system/etc/.has_su_daemon \
    /system/xbin/daemonsu /system/xbin/su /system/xbin/sugote /system/xbin/sugote-mksh /system/xbin/supolicy \
    /system/bin/app_process_init /system/bin/su /cache/su /system/lib/libsupol.so /system/lib64/libsupol.so \
    /system/su.d /system/etc/install-recovery.sh /system/etc/init.d/99SuperSUDaemon /cache/install-recovery.sh \
    /system/.supersu /cache/.supersu /data/.supersu \
    /system/app/Superuser.apk /system/app/SuperSU /cache/Superuser.apk  2>/dev/null
  fi
}

api_level_arch_detect() {
  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
  ARCH32=arm
  IS64BIT=false
  if [ "$ABI" = "x86" ]; then ARCH=x86; ARCH32=x86; fi;
  if [ "$ABI2" = "x86" ]; then ARCH=x86; ARCH32=x86; fi;
  if [ "$ABILONG" = "arm64-v8a" ]; then ARCH=arm64; ARCH32=arm; IS64BIT=true; fi;
  if [ "$ABILONG" = "x86_64" ]; then ARCH=x64; ARCH32=x86; IS64BIT=true; fi;
}

check_data() {
  DATA=false
  DATA_DE=false
  if grep ' /data ' /proc/mounts | grep -vq 'tmpfs'; then
    # Test if data is writable
    touch /data/.rw && rm /data/.rw && DATA=true
    # Test if DE storage is writable
    $DATA && [ -d /data/adb ] && touch /data/adb/.rw && rm /data/adb/.rw && DATA_DE=true
  fi
  $DATA && NVBASE=/data || NVBASE=/cache/data_adb
  $DATA_DE && NVBASE=/data/adb
  resolve_vars
}

find_manager_apk() {
  [ -z $APK ] && APK=/data/adb/magisk.apk
  [ -f $APK ] || APK=/data/magisk/magisk.apk
  [ -f $APK ] || APK=/data/app/com.topjohnwu.magisk*/*.apk
  if [ ! -f $APK ]; then
    DBAPK=`magisk --sqlite "SELECT value FROM strings WHERE key='requester'" 2>/dev/null | cut -d= -f2`
    [ -z $DBAPK ] && DBAPK=`strings /data/adb/magisk.db | grep 5requester | cut -c11-`
    [ -z $DBAPK ] || APK=/data/user_de/*/$DBAPK/dyn/*.apk
    [ -f $APK ] || [ -z $DBAPK ] || APK=/data/app/$DBAPK*/*.apk
  fi
  [ -f $APK ] || ui_print "! Unable to detect Magisk Manager APK for BootSigner"
}

#################
# Module Related
#################

set_perm() {
  chown $2:$3 $1 || return 1
  chmod $4 $1 || return 1
  CON=$5
  [ -z $CON ] && CON=u:object_r:system_file:s0
  chcon $CON $1 || return 1
}

set_perm_recursive() {
  find $1 -type d 2>/dev/null | while read dir; do
    set_perm $dir $2 $3 $4 $6
  done
  find $1 -type f -o -type l 2>/dev/null | while read file; do
    set_perm $file $2 $3 $5 $6
  done
}

mktouch() {
  mkdir -p ${1%/*} 2>/dev/null
  [ -z $2 ] && touch $1 || echo $2 > $1
  chmod 644 $1
}

request_size_check() {
  reqSizeM=`du -ms "$1" | cut -f1`
}

request_zip_size_check() {
  reqSizeM=`unzip -l "$1" | tail -n 1 | awk '{ print int(($1 - 1) / 1048576 + 1) }'`
}

##################################
# Backwards Compatibile Functions
##################################

get_outfd() { setup_flashable; }

mount_magisk_img() {
  $BOOTMODE && MODULE_BASE=modules_update || MODULE_BASE=modules
  MODULEPATH=$NVBASE/$MODULE_BASE
  mkdir -p $MODULEPATH 2>/dev/null
  ln -s $MODULEPATH $MOUNTPATH
}

unmount_magisk_img() {
  rm -f $MOUNTPATH 2>/dev/null
}

boot_actions() { return; }

########
# Setup
########

resolve_vars
