/**
 * OmniCard AI (CRMmp) - 案例作品集详情业务驱动层
 * 严格遵循 uts 强类型规范与 AGENTS.md 约束
 */

import { CardPortalDetail, BentoBlockPublic } from '../../common/types.uts';
import { fetchPortalCard } from '../../common/api.uts';

export type CaseKpi = {
  label: string;
  value: string;
};

type KpiLoose = {
  label?: string;
  name?: string;
  title?: string;
  value?: string | number;
};

export type CaseMetaRecord = {
  images?: string[];
  kpis?: KpiLoose[];
  metrics?: KpiLoose[];
  pdfUrl?: string;
  pdf?: string;
  youtubeUrl?: string;
  youtube?: string;
  url?: string;
  type?: string;
};

export type CaseDetailState = {
  cardId: string;
  blockId: string;
  loading: boolean;
  empty: boolean;
  errorMessage: string;
  title: string;
  content: string;
  images: string[];
  kpis: CaseKpi[];
  pdfUrl: string;
  youtubeUrl: string;
};

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

export const CASE_DETAIL_COPY = {
  empty: '未找到该案例',
  back: '返回',
  cta: '咨询 / 互换',
  pdf: 'PDF',
  youtube: 'YouTube',
  loading: '加载中',
};

/**
 * 创建案例详情初始状态
 */
export function createCaseDetailState(): CaseDetailState {
  return {
    cardId: '',
    blockId: '',
    loading: false,
    empty: false,
    errorMessage: '',
    title: '',
    content: '',
    images: [],
    kpis: [],
    pdfUrl: '',
    youtubeUrl: '',
  };
}

/**
 * 从 onLoad options 读取 cardId / blockId
 */
export function applyCaseDetailOptions(
  state: CaseDetailState,
  options: CaseDetailPageOptions | 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();
  return state.cardId !== '' && state.blockId !== '';
}

/**
 * 从门户聚合数据中选出 id 匹配且 type 为 case 的块；缺块返回 null
 */
export function pickCaseBlock(
  card: CardPortalDetail | null,
  blockId: string
): BentoBlockPublic | null {
  if (card == null || card.bentoBlocks == null || blockId === '') {
    return null;
  }
  const target = String(blockId);
  const blocks = card.bentoBlocks;
  for (let i = 0; i < blocks.length; i++) {
    const block = blocks[i];
    if (String(block.id) === target && block.type === 'case') {
      return block;
    }
  }
  return null;
}

/**
 * 解析 metaJson（字符串或对象）
 */
export function parseCaseMetaJson(raw: string | object | null | undefined): CaseMetaRecord {
  if (raw == null) {
    return {};
  }
  if (typeof raw === 'string') {
    const trimmed = raw.trim();
    if (trimmed === '') {
      return {};
    }
    try {
      return JSON.parse(trimmed) as CaseMetaRecord;
    } catch (_e) {
      return {};
    }
  }
  return raw as CaseMetaRecord;
}

function readTrimmed(value: string | undefined): string {
  return value != null ? String(value).trim() : '';
}

function normalizeKpis(items: KpiLoose[] | undefined): CaseKpi[] {
  if (items == null || !Array.isArray(items)) {
    return [];
  }
  const result: CaseKpi[] = [];
  for (let i = 0; i < items.length; i++) {
    const item = items[i];
    if (item == null) {
      continue;
    }
    const label = readTrimmed(item.label) || readTrimmed(item.name) || readTrimmed(item.title);
    const value = item.value != null ? String(item.value).trim() : '';
    if (label === '' && value === '') {
      continue;
    }
    result.push({
      label: label !== '' ? label : value,
      value: value !== '' ? value : label,
    });
  }
  return result;
}

function collectImages(mediaUrl: string, meta: CaseMetaRecord): string[] {
  const result: string[] = [];
  if (meta.images != null && Array.isArray(meta.images)) {
    for (let i = 0; i < meta.images.length; i++) {
      const src = String(meta.images[i]).trim();
      if (src !== '') {
        result.push(src);
      }
    }
  }
  if (result.length === 0 && mediaUrl !== '') {
    result.push(mediaUrl);
  }
  return result;
}

function resolvePdfUrl(meta: CaseMetaRecord): string {
  const pdfUrl = readTrimmed(meta.pdfUrl);
  if (pdfUrl !== '') {
    return pdfUrl;
  }
  const pdf = readTrimmed(meta.pdf);
  if (pdf !== '') {
    return pdf;
  }
  const url = readTrimmed(meta.url);
  const kind = readTrimmed(meta.type).toLowerCase();
  if (url !== '' && (kind === 'pdf' || url.toLowerCase().indexOf('.pdf') >= 0)) {
    return url;
  }
  return '';
}

function resolveYoutubeUrl(meta: CaseMetaRecord): string {
  const youtubeUrl = readTrimmed(meta.youtubeUrl);
  if (youtubeUrl !== '') {
    return youtubeUrl;
  }
  const youtube = readTrimmed(meta.youtube);
  if (youtube !== '') {
    return youtube;
  }
  const url = readTrimmed(meta.url);
  const kind = readTrimmed(meta.type).toLowerCase();
  const lower = url.toLowerCase();
  if (
    url !== '' &&
    (kind === 'youtube' || lower.indexOf('youtube.com') >= 0 || lower.indexOf('youtu.be') >= 0)
  ) {
    return url;
  }
  return '';
}

function clearCaseContent(state: CaseDetailState): void {
  state.title = '';
  state.content = '';
  state.images = [];
  state.kpis = [];
  state.pdfUrl = '';
  state.youtubeUrl = '';
}

function applyEmpty(state: CaseDetailState): void {
  state.loading = false;
  state.empty = true;
  clearCaseContent(state);
}

function fillFromBlock(state: CaseDetailState, block: BentoBlockPublic): void {
  const meta = parseCaseMetaJson(block.metaJson);
  const mediaUrl = block.mediaUrl != null ? block.mediaUrl.trim() : '';
  state.empty = false;
  state.loading = false;
  state.errorMessage = '';
  state.title = block.title != null ? block.title : '';
  state.content = block.content != null ? block.content : '';
  state.images = collectImages(mediaUrl, meta);
  const kpis = normalizeKpis(meta.kpis);
  state.kpis = kpis.length > 0 ? kpis : normalizeKpis(meta.metrics);
  state.pdfUrl = resolvePdfUrl(meta);
  state.youtubeUrl = resolveYoutubeUrl(meta);
}

/**
 * 用已拉取的门户数据填充案例详情；缺块返空
 */
export function applyPortalCase(
  state: CaseDetailState,
  card: CardPortalDetail | null
): boolean {
  const block = pickCaseBlock(card, state.blockId);
  if (block == null) {
    applyEmpty(state);
    return false;
  }
  fillFromBlock(state, block);
  return true;
}

/**
 * 拉取门户聚合详情并选出 case 块
 */
export async function loadCaseDetail(state: CaseDetailState): Promise<boolean> {
  if (state.cardId === '' || state.blockId === '') {
    applyEmpty(state);
    return false;
  }

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

  try {
    const card = await fetchPortalCard(state.cardId);
    return applyPortalCase(state, card);
  } catch (err) {
    applyEmpty(state);
    if (err instanceof Error) {
      state.errorMessage = err.message;
    } else {
      state.errorMessage = '获取案例详情失败';
    }
    return false;
  }
}

/**
 * 咨询 / 互换页路径
 */
export function buildExchangePath(cardId: string): string {
  return `/pages/portal/exchange?cardId=${cardId}`;
}

/**
 * 跳转无摩擦互换名片
 */
export function openCaseExchange(cardId: string): void {
  const id = cardId != null ? cardId.trim() : '';
  if (id === '') {
    return;
  }
  uni.navigateTo({
    url: buildExchangePath(id),
  });
}

/**
 * 空状态返回上一页
 */
export function goCaseBack(): void {
  uni.navigateBack();
}