import chalk from "chalk";
import { parseHTML } from "linkedom";
import { isEmpty, isNil } from "lodash-es";

import type { FC2Video, FC2Work } from "@/interfaces";
import { nowMs, parseYmdUtc } from "@/utils/dates";
import { FC2_COOKIE } from "@/utils/env";
import { parsePriceJPY } from "@/utils/money";

const SITE_PREFIX = "https://adult.contents.fc2.com";
const FETCH_TIMEOUT_MS = 30_000;

export const articleUrl = (id: string): string => `${SITE_PREFIX}/article/${id}/`;

const fc2Fetch = (url: string): Promise<Response> =>
  fetch(url, {
    headers: { Cookie: FC2_COOKIE },
    signal: AbortSignal.timeout(FETCH_TIMEOUT_MS)
  });

const extractPriceFromCard = (card: Element): { priceYen: number | null; onPromo: boolean } => {
  const priceEl =
    card.querySelector(".c-cntCard-110-f_price") ??
    card.querySelector(".c-price-101") ??
    card.querySelector('[class*="price"]');
  if (isNil(priceEl)) return { priceYen: null, onPromo: false };

  const saleEl =
    priceEl.querySelector(".c-price-101_sale") ??
    priceEl.querySelector(".sale") ??
    card.querySelector(".c-cntCard-110-f_label") ??
    priceEl.querySelector('[class*="sale"]');
  const onPromo = !isNil(saleEl);

  const currentText = saleEl?.textContent ?? priceEl.textContent;
  const priceYen = parsePriceJPY(currentText);
  return { priceYen, onPromo };
};

export const collectWorksFromListing = async (author: string): Promise<FC2Work[]> => {
  const pagination = { page: 1, total: 1 };
  const cards: Element[] = [];

  while (pagination.page <= pagination.total) {
    const targetUrl = new URL(SITE_PREFIX);
    targetUrl.pathname = `/users/${author}/articles`;
    targetUrl.searchParams.set("sort", "date");
    targetUrl.searchParams.set("order", "desc");
    targetUrl.searchParams.set("page", pagination.page.toString());

    console.info(chalk.dim(targetUrl.toString()));

    const res = await fc2Fetch(targetUrl.toString());

    if (!res.ok) {
      console.warn(
        chalk.yellow(`FC2 page ${pagination.page} returned ${res.status}; stopping pagination`)
      );
      break;
    }

    const data = await res.text();
    const { document } = parseHTML(data);
    const pageCards = Array.from(
      document.querySelectorAll(".seller_user_articlesList .c-cntCard-110-f")
    );

    if (pageCards.length === 0) {
      console.warn(
        chalk.yellow(`FC2 page ${pagination.page}: no cards matched (layout changed or empty)`)
      );
    }
    cards.push(...pageCards);

    if (pagination.page === 1) {
      const pageNums = Array.from(document.querySelectorAll(".c-pager-101 .items")).map(
        (item) => parseInt(item.innerHTML) || 0
      );
      const detected = Math.max(0, ...pageNums);
      if (detected === 0 && pageCards.length > 0) {
        console.warn(chalk.yellow("FC2: pager not detected; assuming single page"));
      }
      pagination.total = detected || 1;
    }

    pagination.page++;
  }

  const now = nowMs();
  const works: FC2Work[] = [];
  let dropped = 0;
  for (const card of cards) {
    const aTag = card.querySelector<HTMLAnchorElement>(".c-cntCard-110-f_thumb a");
    if (isNil(aTag)) {
      dropped++;
      continue;
    }
    const { title, href } = aTag;
    const id = new URLSearchParams(href.split("?")[1]).get("id") ?? "";
    if (isEmpty(id)) {
      dropped++;
      continue;
    }
    const duration =
      aTag.querySelector<HTMLSpanElement>("span.c-cntCard-110-f_thumb_num")?.innerHTML ?? null;
    const { priceYen, onPromo } = extractPriceFromCard(card);

    works.push({
      id,
      author,
      title,
      duration: duration || null,
      publishedAt: null,
      priceYen,
      onPromo,
      observedAt: now,
      source: "listing"
    });
  }
  if (dropped > 0) {
    console.warn(chalk.yellow(`FC2: dropped ${dropped}/${cards.length} cards due to missing data`));
  }

  return works;
};

export const collectionVideos = async (author: string): Promise<FC2Video[]> => {
  const works = await collectWorksFromListing(author);
  return works.map((w) => ({
    title: w.title,
    id: w.id,
    url: articleUrl(w.id),
    duration: w.duration ?? "00:00"
  }));
};

const JP_DATE_RE = /(\d{4})[/\-.年](\d{1,2})[/\-.月](\d{1,2})/;

const parseFC2Date = (text: string | null | undefined): number | null => {
  if (!text) return null;
  const m = text.match(JP_DATE_RE);
  if (!m || !m[1] || !m[2] || !m[3]) return null;
  return parseYmdUtc(m[1], m[2], m[3]);
};

const FC2_PPV_PREFIX_RE = /^FC2[- ]PPV[- ]\d+\s+/i;
const FC2_TITLE_SUFFIX_RE = /\s*\|\s*FC2 Content Market.*$/i;

export interface FC2WorkDetail {
  publishedAt: number | null;
  priceYen: number | null;
  onPromo: boolean;
  title: string | null;
}

export const fetchWorkDetail = async (id: string): Promise<FC2WorkDetail> => {
  const url = `${SITE_PREFIX}/article/${id}/`;
  const res = await fc2Fetch(url);
  if (!res.ok) {
    throw new Error(`FC2 detail ${id}: HTTP ${res.status}`);
  }
  const html = await res.text();
  const { document } = parseHTML(html);

  // Title: og:title is the cleanest source — typically "FC2-PPV-{id} {real title}".
  // Fall back to <title>, then strip the id prefix and site suffix. The previous
  // `h1` fallback picked up the site header "Content Market" on every page.
  const ogTitle =
    document.querySelector<HTMLMetaElement>('meta[property="og:title"]')?.getAttribute("content") ??
    document.querySelector("title")?.textContent ??
    null;
  const cleanedTitle = ogTitle
    ? ogTitle.replace(FC2_PPV_PREFIX_RE, "").replace(FC2_TITLE_SUFFIX_RE, "").trim()
    : null;
  const title = cleanedTitle && cleanedTitle.length > 0 ? cleanedTitle : null;

  // Publish date: spec rows live in multiple <div class="items_article_softDevice">
  // blocks; the date one reads "Sale Day : YYYY/MM/DD" (EN) or "販売日 : YYYY/MM/DD" (JP).
  let publishedAt: number | null = null;
  for (const p of Array.from(document.querySelectorAll(".items_article_softDevice p"))) {
    const text = p.textContent;
    if (!text) continue;
    if (!/Sale Day|販売日|发布日|Sold Date/i.test(text)) continue;
    const parsed = parseFC2Date(text);
    if (parsed !== null) {
      publishedAt = parsed;
      break;
    }
  }

  // Price: .normal_price lives inside .items_article_headerPriceArea and on the
  // mylist box. If a sibling element with "sale"/"discount"/"special" in its class
  // is present, that is the active sale price and flags onPromo.
  const priceArea = document.querySelector(".items_article_headerPriceArea");
  const saleEl =
    priceArea?.querySelector(
      '[class*="sale_price"], [class*="discount"], [class*="special_price"]'
    ) ?? null;
  const priceSource =
    saleEl?.textContent ??
    priceArea?.querySelector(".normal_price")?.textContent ??
    document.querySelector(".normal_price")?.textContent ??
    null;
  const priceYen = parsePriceJPY(priceSource);
  const onPromo = saleEl !== null;

  return { publishedAt, priceYen, onPromo, title };
};