Perform Bulk Find and Replace Across Multiple Files

#!/bin/bash

# Usage: ./replace_text.sh <directory> <old_text> <new_text>

DIRECTORY="$1"
OLD_TEXT="$2"
NEW_TEXT="$3"

if [ -z "$DIRECTORY" ] || [ -z "$OLD_TEXT" ] || [ -z "$NEW_TEXT" ]; then
  echo "Usage: $0 <directory> <old_text> <new_text>"
  exit 1
fi

echo "Searching for '$OLD_TEXT' and replacing with '$NEW_TEXT' in files under '$DIRECTORY'..."

# Use find to locate files (e.g., .js, .php, .css, .html) and sed for in-place replacement.
# The -i'' (or -i.bak for backup) is for in-place editing. On macOS, -i requires a backup extension (e.g., -i.bak).
# Use -i'' for no backup (macOS compatible). For Linux, just use -i.
find "$DIRECTORY" -type f \
  -name "*.js" -o -name "*.php" -o -name "*.css" -o -name "*.html" -o -name "*.json" | while read -r file; do
  # Check if file is writable
  if [ -w "$file" ]; then
    echo "Processing $file..."
    # Adjust -i for OS compatibility (Linux vs. macOS)
    # For Linux: sed -i "s/${OLD_TEXT}/${NEW_TEXT}/g" "$file"
    # For macOS: sed -i '' "s/${OLD_TEXT}/${NEW_TEXT}/g" "$file"
    sed -i '' "s/${OLD_TEXT}/${NEW_TEXT}/g" "$file"
  else
    echo "Skipping read-only file: $file"
  fi
done

echo "Replacement complete."