import { Ollama } from "npm:ollama";
import * as cheerio from "npm:cheerio@1.0.0";
import { Readability } from "jsr:@paoramen/cheer-reader";
import type { Config } from "./main.ts";

export async function getNewsUrls(
  config: Config,
  query: string,
): Promise<string[] | undefined> {
  try {
    const response = await fetch(
      `${config.search_url}?q=${query}&format=json`,
    );
    if (!response.ok) {
      throw new Error(
        `Failed to fetch results for query "${query}": ${response.statusText}`,
      );
    }

    const data = await response.json();
    return data.results
      .map((result: { url: string }) => result.url)
      .slice(0, 3);
  } catch (error: any) {
    console.error(
      `Error fetching news URLs for query "${query}":`,
      error.message,
    );
    return undefined;
  }
}

export async function cleanTextFromHtml(url: string): Promise<string> {
  try {
    const response = await fetch(url);
    if (!response.ok) {
      // ToDo: It would be great to fetch additional sources, or skip to next
      throw new Error(`Failed to fetch ${url}: ${response.statusText}`);
    }

    const html = await response.text();
    return htmlToText(html).trim();
  } catch (error: any) {
    console.error(`Error fetching URL '${url}':`, error.message);
    throw error;
  }
}

function htmlToText(html: string): string {
  const $ = cheerio.load(html);
  return new Readability($).parse().textContent || "";
}

export async function answerQuery(
  config: Config,
  query: string,
  texts: string,
) {
  const ollama = new Ollama();
  if (!config.model) {
    throw new Error(`No model in config: ${config}`);
  }
  try {
    const responseStream = await ollama.generate({
      model: config.model,
      prompt:
        `For the topic of ${query}, provide a summary of the information in the following articles:\n${texts}`,
      stream: true,
    });

    for await (const chunk of responseStream) {
      if (!chunk.done) {
        await Deno.stdout.write(new TextEncoder().encode(chunk.response));
      }
    }
  } catch (error: any) {
    console.error("Error answering query:", error.message);
    throw error;
  } finally {
    void ollama;
  }
}