import axios from 'axios';
 
interface Todo {
  id: number;
  userId: number;
  title: string;
  completed: boolean;
}
 
interface PaginationParams {
  pageQueryParam: string;
}
 
type AggregatorCallback = (data: Todo[], aggregatedData: Todo[]) => Todo[];
 
async function fetchAllData(
  url: string,
  paginationParams: PaginationParams,
  aggregator: AggregatorCallback
): Promise<Todo[]> {
  const { pageQueryParam } = paginationParams;
  let currentPage = 1;
  let aggregatedData: Todo[] = [];
 
  try {
    while (true) {
      const response = await axios.get<Todo[]>(url, {
        params: {
          [pageQueryParam]: currentPage,
        },
      });
 
      const { data } = response;
      aggregatedData = aggregator(data, aggregatedData);
 
      if (data.length === 0) {
        // No more data available, exit the loop
        break;
      }
 
      currentPage++;
    }
 
    return aggregatedData;
  } catch (error) {
    console.error('An error occurred:', error);
    throw error;
  }
}
 
// Example aggregator callback that concatenates the fetched todos
const concatenateAggregator: AggregatorCallback = (data, aggregatedData) => {
  return aggregatedData.concat(data);
};
 
// Example usage with the Todos API
const url = 'https://jsonplaceholder.typicode.com/todos';
const paginationParams = {
  pageQueryParam: '_page',
};
 
fetchAllData(url, paginationParams, concatenateAggregator)
  .then((todos) => {
    console.log('Aggregated todos:', todos);
  })
  .catch((error) => {
    console.error('Error:', error);
  });