enhance app installation

Instead of copying to /data/local we now install using a pipe,
which will not yield any file access issues anymore.
Additionally now the app will be upgraded if it exists already,
and will only be deactivated if it didn't exist beforehand.
This will make it possible to update at any point in time
and postpone the restart to a more convenient time.

Author: programminghoch10

magiskmodule/customize.sh

@@ -12,9 +12,6 @@ IFS=$'\n'
 SEARCH_ROOT="$(magisk --path)/.magisk/mirror"/
 [ ! -d "$SEARCH_ROOT" ] && SEARCH_ROOT=/
 
-# Uninstall v4a app if installed
-[ -n "$(pm list packages | grep "$VIPERFXPACKAGE")" ] && pm uninstall -k "$VIPERFXPACKAGE" &>/dev/null
-
 # Create the scoped storage directory
 mkdir -p "$FOLDER"
 
@@ -107,15 +104,18 @@ for ORIGINAL_FILE in $AUDIO_EFFECTS_FILES; do
 done
 
 ui_print "- Installing the ViPER4AndroidFX user app"
-APK_INSTALL_FOLDER="/data/local"
-(
-  cp -f "$MODPATH"/v4afx.apk "$APK_INSTALL_FOLDER"/v4afx.apk || exit 1
-  pm install "$APK_INSTALL_FOLDER"/v4afx.apk &>/dev/null
-  RET=$?
-  rm "$APK_INSTALL_FOLDER"/v4afx.apk
-  exit $RET
-) || abort "Failed to install V4AFX!"
-pm disable "$VIPERFXPACKAGE" &>/dev/null
+APK=v4afx.apk
+[ -n "$(pm list packages | grep "^package:$VIPERFXPACKAGE$")" ] && APK_UPGRADE=true || APK_UPGRADE=false
+APK_SIZE=$(stat -c %s "$MODPATH"/"$APK")
+installAPK() {
+  pm install --install-location 1 --pkg "$VIPERFXPACKAGE" -S $APK_SIZE < "$MODPATH"/"$APK" &>/dev/null
+}
+installAPK || {
+  $APK_UPGRADE && pm uninstall -k "$VIPERFXPACKAGE" &>/dev/null
+  APK_UPGRADE=false
+  installAPK
+} || abort "Failed to install V4AFX!"
+! $APK_UPGRADE && pm disable "$VIPERFXPACKAGE" &>/dev/null
 
 ui_print "- Configuring ViPER4Android"
 VIPERFXPREFS="$(pm dump "$VIPERFXPACKAGE" | grep dataDir | head -n 1 | cut -d'=' -f2)"