#!/bin/bash

BASE_URL="${1}"
OUTPUT_DIR="${2:-.}"

if [ -z "$BASE_URL" ]; then
  echo "Usage: $0 <base_url> [output_dir]"
  exit 1
fi

# Скачиваем базовый файл
echo "Downloading base file..."
curl -L -f -o "${OUTPUT_DIR}/$(basename "$BASE_URL")" "$BASE_URL"

if [ $? -ne 0 ]; then
  echo "Failed to download base file."
  exit 1
fi

# Скачиваем части, пока они существуют
i=1
while true; do
  PART_URL="${BASE_URL}.${i}"

  # Проверяем существование файла через HEAD-запрос
  HTTP_CODE=$(curl -L -s -o /dev/null -w "%{http_code}" -I "$PART_URL")

  if [ "$HTTP_CODE" -ne 200 ]; then
    echo "No more parts found (last checked: ${PART_URL}). Download complete."
    break
  fi

  OUTPUT_FILE="${OUTPUT_DIR}/$(basename "$PART_URL")"
  echo "Downloading part ${i}: ${PART_URL}..."
  curl -L -f -o "$OUTPUT_FILE" "$PART_URL"

  if [ $? -ne 0 ]; then
    echo "Failed to download part ${i}: ${PART_URL}"
    exit 1
  fi

  i=$((i + 1))
done

echo "All files downloaded successfully."