Watch and render .css.erb templates with Tailwind

tailwind-watch

#!/usr/bin/env sh

INPUT_FILE=""
OUTPUT_FILE=""
WATCH=false
TAILWIND_FLAGS=""
TAILWIND_SCRIPT="$(dirname "$0")/tailwind-erb"
TAILWIND_PID=0

print_help() {
  echo "Usage: $0 -i <input_file> -o <output_file> [--watch] [<tailwind_flags>]"
}

# Parse arguments
while [ "$#" -gt 0 ]; do
  case "$1" in
    -h|--help)
      print_help
      exit 0
      ;;
    -i|--input)
      INPUT_FILE="$2"
      shift 2
      ;;
    -o|--output)
      OUTPUT_FILE="$2"
      shift 2
      ;;
    --watch)
      WATCH=true
      shift
      ;;
    *)
      TAILWIND_FLAGS="$TAILWIND_FLAGS $1"
      shift
      ;;
  esac
done

if [ -z "$INPUT_FILE" ] || [ -z "$OUTPUT_FILE" ]; then
  print_help
  exit 1
fi

get_modified_time() {
  if command -v stat >/dev/null 2>&1; then
    if stat --version >/dev/null 2>&1; then
      stat -c %Y "$INPUT_FILE" 2>/dev/null
    else
      stat -f %m "$INPUT_FILE" 2>/dev/null
    fi
  else
    echo "0"
  fi
}

start_tailwind() {
  if [ "$TAILWIND_PID" -eq 0 ]; then
    echo "Starting tailwind process..."
    local flags="$TAILWIND_FLAGS"

    if [ "$WATCH" = "true" ]; then
      flags="--watch $flags"
    fi

    "$TAILWIND_SCRIPT" -i "$INPUT_FILE" -o "$OUTPUT_FILE" $flags &
    TAILWIND_PID=$!
  fi
}

stop_tailwind() {
  if [ "$TAILWIND_PID" -ne 0 ]; then
    echo "Stopping tailwind process and its children..."
    disown "$TAILWIND_PID" 2>/dev/null
    pkill -P "$TAILWIND_PID" 2>/dev/null
    kill "$TAILWIND_PID" 2>/dev/null
    TAILWIND_PID=0
  fi
}

if [ "$WATCH" = "true" ]; then
  echo "Watching $INPUT_FILE for changes..."
  LAST_MODIFIED=$(get_modified_time "$INPUT_FILE")
  start_tailwind

  while true; do
    sleep 1
    NEW_MODIFIED=$(get_modified_time "$INPUT_FILE")
    if [ "$NEW_MODIFIED" -gt "$LAST_MODIFIED" ]; then
      LAST_MODIFIED=$NEW_MODIFIED
      stop_tailwind
      start_tailwind
    fi
  done
else
  "$TAILWIND_SCRIPT" -i "$INPUT_FILE" -o "$OUTPUT_FILE" $TAILWIND_FLAGS
fi