import { GuardianClient } from '../api/guardian-client.js';
import { LookbackParamsSchema } from '../types/guardian.js';
import { formatArticleResponse, validateDate } from '../utils/formatters.js';
export async function guardianLookback(client: GuardianClient, args: any): Promise<string> {
const params = LookbackParamsSchema.parse(args);
const fromDate = validateDate(params.date);
if (!fromDate) {
throw new Error(`Invalid date format: ${params.date}. Use YYYY-MM-DD format.`);
}
const searchParams: Record<string, any> = {
'from-date': fromDate,
'order-by': 'newest',
'page-size': params.page_size || 20,
'show-fields': 'headline,standfirst,byline,publication,firstPublicationDate'
};
if (params.end_date) {
const toDate = validateDate(params.end_date);
if (!toDate) {
throw new Error(`Invalid end_date format: ${params.end_date}. Use YYYY-MM-DD format.`);
}
searchParams['to-date'] = toDate;
} else {
// If no end date, use the same date
searchParams['to-date'] = fromDate;
}
if (params.section) {
searchParams.section = params.section;
}
const response = await client.search(searchParams);
const articles = response.response.results;
const pagination = response.response;
// For search results, default to truncated content for performance
const formatOptions = { truncate: true, maxLength: 500 };
return formatArticleResponse(articles, pagination, formatOptions);
}