make compession level adjustable

backup.sh

@@ -95,6 +95,20 @@ fi
 
 clear
 
+if [ ! -v compression_level ]; then
+  cecho "Choose the compression level."
+  cecho "- 0 is no compression, and is the fastest."
+  cecho "- 9 is the slowest, but provides the best compression."
+  cecho "- 7 was the previous default"
+  cecho "Press Enter to pick your preferred compression level."
+  wait_for_enter
+
+  compression_levels=( '0' '1' '2' '3' '4' '5' '6' '7' '8' '9' )
+  select_option_from_list "Choose the compression level" compression_levels[@] compression_level
+fi
+
+clear
+
 if [ ! -v use_hooks ]; then
   cecho "Would you like to use hooks?"
   cecho "Choose 'no' if you don't understand this question, or don't want to load hooks."

functions/backup_func.sh

@@ -122,7 +122,7 @@ function backup_func() {
     # -bb3: verbose logging
     # The undefined variable (archive_password) is set by the user if they're using unattended mode
     declare backup_archive="$archive_path/open-android-backup-$(date +%m-%d-%Y-%H-%M-%S).7z"
-    retry 5 7z a -p"$archive_password" -mhe=on -mx=7 -bb3 "$backup_archive" backup-tmp/*
+    retry 5 7z a -p"$archive_password" -mhe=on -mx=$compression_level -bb3 "$backup_archive" backup-tmp/*
   fi
 
   # We're not using 7-Zip's -sdel option (delete files after compression) to honor the user's choice to securely delete temporary files after a backup