/**
 * Ozon SSR widget state 提取器（主路径）
 *
 * Ozon 页面把每个 widget 的 JSON state 内嵌在 DOM 里：
 *   <div id="state-webGallery-3311626-default-1" data-state='{...}'>
 * content script 直接读 data-state 即可，无需访问页面 JS（main world）。
 *
 * 结构已在真实页面实测（reference/ozon1.html、ozon2.html）：
 *   - webGallery:  coverImage / images[{src,alt}]（原图）/ videos[{url,coverUrl}]
 *   - webPrice:    price / originalPrice / cardPrice（如 "108,26 ¥"）
 *   - webProductHeading: title
 *   - webShortCharacteristics / webDetailedCharacteristics: characteristics[]
 *   - webAspects:  aspects[].variants[].data.{searchableText, coverImage}（SKU 变体）
 *   - webReviewProductScore: totalScore / reviewsCount
 *
 * ★ 白名单机制：只读上面这几个 widget 的 state。
 *   绝不遍历全页 —— "为您推荐 / 一起购买" 等其它商品 carousel 的 state
 *   （webRecommendedProducts / webCarousel / 类似 widget）根本不会被读到。
 */
import { toAbsoluteUrl } from './url';

export interface OzonVariant {
  name: string;
  image?: string; // 可能为 undefined（纯文字规格，如尺码）
}

export interface BreadcrumbItem {
  name: string;            // 类目名称（如"扑满"、"儿童房"）
  href: string;            // 原始链接（/category/kopilki-15056/ 或 ?category=7041）
  searchCategoryId?: number; // Ozon 搜索类目 ID（从 ?category=xxx 解析）
  slug?: string;           // URL slug（从 /category/xxx-123/ 解析，含数字 ID）
}

export interface OzonStateData {
  title?: string;
  price?: string;
  originalPrice?: string;
  rating?: string;
  reviewCount?: string;
  galleryImages: string[]; // 原图（无尺寸标记）
  videos: string[];
  videoCovers: string[];
  skuVariants: OzonVariant[];
  characteristics: Array<{ key: string; value: string }>;
  breadcrumbs: BreadcrumbItem[]; // 面包屑类目路径
}

/** 允许读取的 widget 前缀白名单 */
const ALLOWED_WIDGETS = [
  'webGallery-',
  'webPrice-',
  'webProductHeading-',
  'webShortCharacteristics-',
  'webDetailedCharacteristics-',
  'webCharacteristics-',
  'webAspects-',
  'webReviewProductScore-',
  'breadCrumbs-',  // 面包屑类目路径
];

function pushUnique(arr: string[], v: string): void {
  const abs = toAbsoluteUrl(v);
  if (abs && !arr.includes(abs)) arr.push(abs);
}

function readTextRs(node: unknown): string {
  // 提取 textRs / descriptionRs 里的展示文本。
  // 规则：content/text 字段的值收进文本；递归进入数组/对象找嵌套的 content/text；
  // 跳过 type/font/color/id/href 等样式与元数据字段（type=newLine 除外）。
  if (node == null) return '';
  if (typeof node === 'string') return node.trim();
  if (typeof node !== 'object') return '';
  const texts: string[] = [];
  const walk = (n: unknown): void => {
    if (!n) return;
    if (typeof n === 'string') {
      texts.push(n);
      return;
    }
    if (Array.isArray(n)) {
      n.forEach(walk);
      return;
    }
    if (typeof n === 'object') {
      for (const [k, v] of Object.entries(n as Record<string, unknown>)) {
        if (k === 'type' && (v === 'newLine' || v === 'lineBreak')) {
          texts.push('\n');
        } else if (k === 'content' || k === 'text') {
          walk(v);
        } else if (v && typeof v === 'object') {
          walk(v);
        }
        // 其它原始值（font/color/id/type='text' 等）直接跳过
      }
    }
  };
  walk(node);
  return texts.join('').trim();
}

function parseCharacteristics(chars: unknown): Array<{ key: string; value: string }> {
  if (!Array.isArray(chars)) return [];
  const out: Array<{ key: string; value: string }> = [];
  for (const c of chars) {
    if (!c || typeof c !== 'object') continue;
    const row = c as Record<string, unknown>;
    // 结构 A：{ title: { textRs: [...] }, values: [{ text: ... }] }（实测）
    const key = readTextRs(row.title);
    if (Array.isArray(row.values)) {
      const vals = row.values
        .map((v) => (v && typeof v === 'object' ? readTextRs((v as Record<string, unknown>).text) : ''))
        .map((t) => t.replace(/,\s*$/, '')) // 源数据值自带尾逗号（如 "音乐, "）
        .filter(Boolean);
      if (key && vals.length) out.push({ key, value: vals.join(', ') });
      continue;
    }
    // 结构 B：{ key, value } / { name, value } / { title, text }
    const k2 = (row.key ?? row.name ?? row.title) as string | undefined;
    const v2 = (row.value ?? row.text) as string | undefined;
    if (typeof k2 === 'string' && k2 && typeof v2 === 'string' && v2) {
      out.push({ key: k2, value: v2 });
    }
  }
  return out;
}

export function extractOzonState(): OzonStateData {
  const data: OzonStateData = {
    galleryImages: [],
    videos: [],
    videoCovers: [],
    skuVariants: [],
    characteristics: [],
    breadcrumbs: [],
  };
  const seenChars = new Set<string>();

  const els = document.querySelectorAll('div[id^="state-"]');
  for (const el of Array.from(els)) {
    const id = el.id.slice('state-'.length);
    if (!ALLOWED_WIDGETS.some((p) => id.startsWith(p))) continue;
    const raw = el.getAttribute('data-state');
    if (!raw) continue;
    let state: unknown;
    try {
      state = JSON.parse(raw);
    } catch {
      continue;
    }
    if (!state || typeof state !== 'object') continue;
    const s = state as Record<string, unknown>;

    if (id.startsWith('webGallery-')) {
      if (typeof s.coverImage === 'string') pushUnique(data.galleryImages, s.coverImage);
      if (Array.isArray(s.images)) {
        for (const img of s.images) {
          const src = img && typeof (img as Record<string, unknown>).src === 'string'
            ? (img as Record<string, unknown>).src as string
            : undefined;
          if (src) pushUnique(data.galleryImages, src);
        }
      }
      if (Array.isArray(s.videos)) {
        for (const v of s.videos) {
          const rec = v as Record<string, unknown>;
          if (typeof rec.url === 'string') pushUnique(data.videos, rec.url);
          if (typeof rec.coverUrl === 'string') pushUnique(data.videoCovers, rec.coverUrl);
        }
      }
    } else if (id.startsWith('webPrice-')) {
      if (typeof s.price === 'string') data.price = s.price;
      if (typeof s.originalPrice === 'string') data.originalPrice = s.originalPrice;
      if (!data.price && typeof s.cardPrice === 'string') data.price = s.cardPrice;
    } else if (id.startsWith('webProductHeading-')) {
      if (typeof s.title === 'string') data.title = s.title;
    } else if (
      id.startsWith('webShortCharacteristics-') ||
      id.startsWith('webDetailedCharacteristics-') ||
      id.startsWith('webCharacteristics-')
    ) {
      for (const c of parseCharacteristics(s.characteristics)) {
        const k = `${c.key}::${c.value}`;
        if (!seenChars.has(k)) {
          seenChars.add(k);
          data.characteristics.push(c);
        }
      }
    } else if (id.startsWith('webAspects-')) {
      if (Array.isArray(s.aspects)) {
        for (const aspect of s.aspects) {
          const a = aspect as Record<string, unknown>;
          if (!Array.isArray(a.variants)) continue;
          for (const v of a.variants) {
            const rec = v as Record<string, unknown>;
            const d = rec.data as Record<string, unknown> | undefined;
            const name = typeof d?.searchableText === 'string' ? d.searchableText
              : typeof d?.title === 'string' ? d.title : '';
            const image = typeof d?.coverImage === 'string' ? d.coverImage : undefined;
            if (name) data.skuVariants.push({ name, image });
          }
        }
      }
    } else if (id.startsWith('webReviewProductScore-')) {
      if (typeof s.totalScore === 'number') data.rating = String(s.totalScore);
      if (typeof s.reviewsCount === 'number') data.reviewCount = String(s.reviewsCount);
    } else if (id.startsWith('breadCrumbs-')) {
      // breadCrumbs widget state: { breadcrumbs: [{text, link, crumbType}] }
      if (Array.isArray(s.breadcrumbs) && data.breadcrumbs.length === 0) {
        for (const crumb of s.breadcrumbs) {
          const c = crumb as Record<string, unknown>;
          const name = typeof c.text === 'string' ? c.text.trim() : '';
          const href = typeof c.link === 'string' ? c.link : '';
          if (!name || !href) continue;
          // 解析 ?category=7041（highlight 样式链接）
          const catMatch = href.match(/[?&]category=(\d+)/);
          const searchCategoryId = catMatch ? Number(catMatch[1]) : undefined;
          // 解析 /category/kopilki-15056/（末尾带数字 ID 的 slug）
          const slugMatch = href.match(/\/category\/([^/?]+)/);
          const slug = slugMatch ? slugMatch[1] : undefined;
          data.breadcrumbs.push({ name, href, searchCategoryId, slug });
        }
      }
    }
  }

  // 如果 widget state 没有面包屑（旧版页面），尝试读 DOM 渲染的 ol
  if (data.breadcrumbs.length === 0) {
    const ol = document.querySelector('[class*="breadCrumbs"] ol, nav ol, ol[class*="breadcrumb"]');
    if (ol) {
      for (const a of Array.from(ol.querySelectorAll('a[href]'))) {
        const href = a.getAttribute('href') ?? '';
        const name = a.textContent?.trim() ?? '';
        if (!name) continue;
        const catMatch = href.match(/[?&]category=(\d+)/);
        const searchCategoryId = catMatch ? Number(catMatch[1]) : undefined;
        const slugMatch = href.match(/\/category\/([^/?]+)/);
        const slug = slugMatch ? slugMatch[1] : undefined;
        data.breadcrumbs.push({ name, href, searchCategoryId, slug });
      }
    }
  }

  return data;
}