import { rankAndDedupe, type RankedPost } from "@/lib/ranking";
import { withSharedContext } from "./browser";
import { humanLandingPause, humanScrollPage } from "./human-behavior";
import type { BrowserProgressCallback } from "./progress";
import { extractFromPageScripts, extractPostsFromJson } from "./extract";
import type { ThreadsPost } from "./types";
import { assertThreadsPageSafe } from "./safety";

function attachCollector(page: import("playwright").Page, collected: ThreadsPost[]) {
  page.on("response", async (response) => {
    const url = response.url();
    if (!url.includes("graphql") && !url.includes("threads") && !url.includes("instagram")) return;
    try {
      const contentType = response.headers()["content-type"] ?? "";
      if (!contentType.includes("json")) return;
      const json = await response.json();
      extractPostsFromJson(json, collected);
    } catch {
      // ignore
    }
  });
}

async function scrapeProfileDom(page: import("playwright").Page, username: string): Promise<ThreadsPost[]> {
  const posts: ThreadsPost[] = [];
  const seen = new Set<string>();
  const links = page.locator('a[href*="/post/"]');
  const count = await links.count();

  for (let i = 0; i < Math.min(count, 35); i++) {
    const link = links.nth(i);
    try {
      const href = await link.getAttribute("href", { timeout: 1200 });
      if (!href || seen.has(href)) continue;
      seen.add(href);
      const permalink = href.startsWith("http") ? href : `https://www.threads.com${href}`;
      const authorName = href.match(/@([^/]+)\/post/)?.[1] ?? username;
      const container = link.locator("xpath=ancestor::*[contains(@data-pressable-container,'true')][1]");
      const scope = (await container.count()) > 0 ? container : link.locator("xpath=ancestor::div[position()<=6]").first();
      const text = await scope.locator('div[dir="auto"], span[dir="auto"]').first().innerText({ timeout: 1200 }).catch(() => "");
      if (!text || text.length < 3) continue;
      posts.push({
        text: text.trim(),
        permalink,
        authorName,
        externalId: href.match(/\/post\/([^/?]+)/)?.[1],
      });
    } catch {
      // skip
    }
  }
  return posts;
}

/** 在既有 page 上抓取帳號近期貼文 */
export async function getProfilePostsOnPage(
  page: import("playwright").Page,
  username: string,
  limit = 15,
  onStep?: BrowserProgressCallback
): Promise<RankedPost[]> {
  const clean = username.replace(/^@/, "").trim();
  const collected: ThreadsPost[] = [];
  attachCollector(page, collected);

  const profileUrl = `https://www.threads.com/@${encodeURIComponent(clean)}`;
  await onStep?.("open_page", `@${clean}`);
  const response = await page.goto(profileUrl, { waitUntil: "domcontentloaded", timeout: 45000 });
  await onStep?.("landing_pause");
  await humanLandingPause(page);

  const bodyText = await page.locator("body").innerText();
  await assertThreadsPageSafe(page, response?.status(), bodyText);
  if (bodyText.includes("走丟") || bodyText.includes("找不到")) {
    await onStep?.("done", "0 篇");
    return [];
  }

  await onStep?.("wait_content");
  await page.waitForSelector('a[href*="/post/"]', { timeout: 10000 }).catch(() => undefined);
  await onStep?.("scroll");
  await humanScrollPage(page, { minPasses: 2, maxPasses: 4 });

  if (collected.length < 2) {
    await onStep?.("parse_scripts");
    const { posts } = await extractFromPageScripts(page);
    collected.push(...posts);
  } else {
    await onStep?.("parse_network", `${collected.length} 篇`);
  }
  if (collected.length < 2) {
    await onStep?.("parse_dom");
    collected.push(...(await scrapeProfileDom(page, clean)));
  }

  const ranked = rankAndDedupe(
    collected.map((p) => ({ ...p, authorName: p.authorName ?? clean })),
    limit
  );
  await onStep?.("done", `${ranked.length} 篇`);
  return ranked;
}

export async function getProfilePosts(
  storageState: string,
  username: string,
  limit = 15
): Promise<RankedPost[]> {
  return withSharedContext(storageState, async (context) => {
    const page = await context.newPage();
    return getProfilePostsOnPage(page, username, limit);
  });
}