diff --git a/scripts/copy-language-pack.sh b/scripts/copy-language-pack.sh
index 5737a1b80..186767ede 100644
--- a/scripts/copy-language-pack.sh
+++ b/scripts/copy-language-pack.sh
@@ -1,26 +1,40 @@
-browser_locales=engine/browser/locales
+#!/bin/bash
+
+# Constants
+BROWSER_LOCALES="engine/browser/locales"
+L10N_DIR="./l10n"
+SUPPORTED_LANGS=("en-US" "fr" "de" "es") # Add any other supported languages
 
 copy_browser_locales() {
-  langId=$1
-  mkdir -p "$browser_locales/$langId"
+  local langId="$1"
+  mkdir -p "$BROWSER_LOCALES/$langId" || { echo "Error: Failed to create directory $BROWSER_LOCALES/$langId"; exit 1; }
   
   if [ "$langId" = "en-US" ]; then
-    find "$browser_locales/$langId" -type f -name "zen*" -delete
-    rsync -av --exclude=.git ./l10n/en-US/browser/ "$browser_locales/$langId/"
+    # Remove specific files for en-US
+    find "$BROWSER_LOCALES/$langId" -type f -name "zen*" -delete || { echo "Error: Failed to delete zen files in $BROWSER_LOCALES/$langId"; exit 1; }
+    rsync -av --exclude=.git "$L10N_DIR/en-US/browser/" "$BROWSER_LOCALES/$langId/" || { echo "Error: rsync failed for en-US"; exit 1; }
     return
   fi
   
-  rm -rf "$browser_locales/$langId/"
-  
-  # TODO: Copy the rest of the l10n directories to their respective locations
-  rsync -av --exclude=.git "./l10n/$langId/" "$browser_locales/$langId/"
+  rm -rf "$BROWSER_LOCALES/$langId/" || { echo "Error: Failed to remove existing directory $BROWSER_LOCALES/$langId"; exit 1; }
+
+  # Copy the rest of the l10n directories to their respective locations
+  rsync -av --exclude=.git "$L10N_DIR/$langId/" "$BROWSER_LOCALES/$langId/" || { echo "Error: rsync failed for $langId"; exit 1; }
 }
 
+# Check if a language was specified
 if [ -z "$1" ]; then
   echo "Error: No language specified."
   exit 1
 fi
 
-LANG=$1
+LANG="$1"
+
+# Validate input language against supported languages
+if [[ ! " ${SUPPORTED_LANGS[@]} " =~ " $LANG " ]]; then
+  echo "Error: Unsupported language '$LANG'. Supported languages are: ${SUPPORTED_LANGS[*]}"
+  exit 1
+fi
+
 echo "Copying language pack for $LANG"
 copy_browser_locales "$LANG"