/**
 * OmniCard AI (CRMmp) - 深度洞见文章详情业务驱动层
 * 严格遵循 uts 强类型规范与 AGENTS.md 约束
 */

import { BentoBlockPublic } from '../../common/types.uts';
import { fetchPortalCard } from '../../common/api.uts';
import { getCurrentLocale, getOmniText } from '../../common/locale.uts';

export type ArticleDetailPageOptions = {
  cardId?: string;
  blockId?: string;
  id?: string;
};

export type ArticleOpenGraph = {
  title: string;
  description: string;
  image: string;
};

export type ArticleShareFields = {
  ctaLabel: string;
  copiedToast: string;
  shareUrl: string;
  title: string;
  description: string;
  image: string;
};

export type ArticleDetailState = {
  cardId: string;
  blockId: string;
  loading: boolean;
  article: BentoBlockPublic | null;
  title: string;
  content: string;
  mediaUrl: string;
  linkUrl: string;
  isHtmlContent: boolean;
  empty: boolean;
  errorMessage: string;
  openGraph: ArticleOpenGraph;
};

const SHARE_CTA_LABEL = '复制链接';
const BACK_LABEL = '返回';
const OG_DESC_MAX = 160;

/**
 * 创建文章详情初始状态
 */
export function createArticleDetailState(): ArticleDetailState {
  return {
    cardId: '',
    blockId: '',
    loading: false,
    article: null,
    title: '',
    content: '',
    mediaUrl: '',
    linkUrl: '',
    isHtmlContent: false,
    empty: false,
    errorMessage: '',
    openGraph: {
      title: '',
      description: '',
      image: '',
    },
  };
}

/**
 * 将详情状态复位为空
 */
export function applyEmptyArticle(state: ArticleDetailState): void {
  state.article = null;
  state.title = '';
  state.content = '';
  state.mediaUrl = '';
  state.linkUrl = '';
  state.isHtmlContent = false;
  state.empty = true;
  state.openGraph = {
    title: '',
    description: '',
    image: '',
  };
}

/**
 * 从 onLoad options 写入 cardId / blockId
 */
export function applyArticleDetailOptions(
  state: ArticleDetailState,
  options: ArticleDetailPageOptions | null
): boolean {
  const cardIdRaw = options != null ? options.cardId || options.id || '' : '';
  const blockIdRaw = options != null ? options.blockId || '' : '';
  state.cardId = String(cardIdRaw).trim();
  state.blockId = String(blockIdRaw).trim();

  if (state.cardId === '' || state.blockId === '') {
    applyEmptyArticle(state);
    return false;
  }
  return true;
}

/**
 * 从 bentoBlocks 中选出指定 article 块
 */
export function pickArticleBlock(
  blocks: BentoBlockPublic[] | null | undefined,
  blockId: string
): BentoBlockPublic | null {
  if (blocks == null || !Array.isArray(blocks) || blocks.length === 0) {
    return null;
  }
  const targetId = blockId != null ? String(blockId).trim() : '';
  if (targetId === '') {
    return null;
  }
  for (let i = 0; i < blocks.length; i++) {
    const block = blocks[i];
    if (block != null && String(block.id) === targetId && block.type === 'article') {
      return block;
    }
  }
  return null;
}

/**
 * 正文是否像 HTML，供 rich-text / text 分流
 */
export function looksLikeHtml(content: string): boolean {
  if (content == null || content.trim() === '') {
    return false;
  }
  return /<\s*\/?\s*[a-zA-Z][^>]*>/.test(content);
}

/**
 * 去掉 HTML 标签，折叠空白
 */
export function stripHtmlToText(raw: string): string {
  if (raw == null || raw === '') {
    return '';
  }
  return raw.replace(/<[^>]+>/g, ' ').replace(/\s+/g, ' ').trim();
}

/**
 * 供后续 H5 meta 使用的 OpenGraph 三件套
 */
export function buildArticleOpenGraph(article: BentoBlockPublic | null): ArticleOpenGraph {
  if (article == null) {
    return {
      title: '',
      description: '',
      image: '',
    };
  }
  const desc = stripHtmlToText(article.content != null ? article.content : '');
  let description = desc;
  if (description.length > OG_DESC_MAX) {
    description = description.substring(0, OG_DESC_MAX - 3) + '...';
  }
  return {
    title: article.title != null ? article.title : '',
    description,
    image: article.mediaUrl != null ? article.mediaUrl : '',
  };
}

/**
 * 分享链接：优先块 linkUrl，否则当前页 URL
 */
export function resolveShareUrl(linkUrl: string, pageUrl: string): string {
  const fromBlock = linkUrl != null ? linkUrl.trim() : '';
  if (fromBlock !== '') {
    return fromBlock;
  }
  return pageUrl != null ? pageUrl.trim() : '';
}

/**
 * 构造当前页路径兜底
 */
export function buildArticlePagePath(cardId: string, blockId: string): string {
  return `/pages/portal/article-detail?cardId=${cardId}&blockId=${blockId}`;
}

type UniStackPage = {
  route?: string;
};

/**
 * 读取当前页 URL：优先页面栈，否则构造本地路径
 */
export function getCurrentPageUrl(state: ArticleDetailState): string {
  try {
    const pages = uni.getCurrentPages();
    if (pages != null && pages.length > 0) {
      const page = pages[pages.length - 1] as UniStackPage;
      const route = page != null && page.route != null ? String(page.route) : '';
      if (route !== '') {
        const path = route.startsWith('/') ? route : `/${route}`;
        return `${path}?cardId=${state.cardId}&blockId=${state.blockId}`;
      }
    }
  } catch (_e) {}

  return buildArticlePagePath(state.cardId, state.blockId);
}

/**
 * 分享文案与 OpenGraph 字段（CTA / Toast / URL / title / description / image）
 */
export function getArticleShareFields(
  state: ArticleDetailState,
  pageUrl: string
): ArticleShareFields {
  const og = state.openGraph;
  return {
    ctaLabel: SHARE_CTA_LABEL,
    copiedToast: getOmniText(getCurrentLocale(), 'portal.copied_link'),
    shareUrl: resolveShareUrl(state.linkUrl, pageUrl),
    title: og.title,
    description: og.description,
    image: og.image,
  };
}

export function getArticleBackLabel(): string {
  return BACK_LABEL;
}

export function getArticleEmptyMessage(): string {
  return getOmniText(getCurrentLocale(), 'common.empty');
}

function applyArticle(state: ArticleDetailState, article: BentoBlockPublic): void {
  state.article = article;
  state.title = article.title != null ? article.title : '';
  state.content = article.content != null ? article.content : '';
  state.mediaUrl = article.mediaUrl != null ? article.mediaUrl : '';
  state.linkUrl = article.linkUrl != null ? article.linkUrl : '';
  state.isHtmlContent = looksLikeHtml(state.content);
  state.empty = false;
  state.openGraph = buildArticleOpenGraph(article);
}

/**
 * fetchPortalCard 后从 bentoBlocks 选出 article
 */
export async function loadArticleDetail(
  state: ArticleDetailState
): Promise<BentoBlockPublic | null> {
  if (state.cardId === '' || state.blockId === '') {
    applyEmptyArticle(state);
    return null;
  }

  state.loading = true;
  state.errorMessage = '';

  try {
    const card = await fetchPortalCard(state.cardId);
    const blocks = card != null && card.bentoBlocks != null ? card.bentoBlocks : [];
    const article = pickArticleBlock(blocks, state.blockId);
    state.loading = false;

    if (article == null) {
      applyEmptyArticle(state);
      return null;
    }

    applyArticle(state, article);
    return article;
  } catch (err) {
    state.loading = false;
    applyEmptyArticle(state);
    if (err instanceof Error) {
      state.errorMessage = err.message;
    } else {
      state.errorMessage = getOmniText(getCurrentLocale(), 'portal.unavailable');
    }
    return null;
  }
}

/**
 * 主 CTA：复制 linkUrl 或当前页 URL
 */
export function copyArticleShareLink(state: ArticleDetailState, pageUrl?: string): boolean {
  const fallback = pageUrl != null && pageUrl !== '' ? pageUrl : getCurrentPageUrl(state);
  const shareUrl = resolveShareUrl(state.linkUrl, fallback);
  if (shareUrl === '') {
    return false;
  }

  uni.setClipboardData({
    data: shareUrl,
    success: () => {
      uni.showToast({
        title: getOmniText(getCurrentLocale(), 'portal.copied_link'),
        icon: 'none',
      });
    },
  });
  return true;
}

/**
 * 空状态返回：优先回退上一页
 */
export function goBackFromArticle(state: ArticleDetailState): void {
  uni.navigateBack({
    delta: 1,
    fail: () => {
      const query = state.cardId !== '' ? `?id=${state.cardId}` : '';
      uni.reLaunch({
        url: `/pages/portal/index${query}`,
      });
    },
  });
}